Question: A 69-year-old man presents to the emergency department with shortness of breath. The patient has presented 3 times this month with similar complaints. He states his shortness of breath started when he was walking from his car to a local restaurant. He does not see a primary care physician and is not currently taking any medications. He drinks alcohol socially and does not smoke. His temperature is 99.5°F (37.5°C), pulse is 100/min, blood pressure is 130/90 mmHg, respirations are 18/min, and oxygen saturation is 96% on room air. On physical exam, he appears fatigued and the cardiovascular exam reveals an additional heart sound after S2. A pulmonary exam is notable for bilateral crackles and an abdominal exam reveals an obese abdomen without pain in any of the quadrants. Lower extremity pitting edema is noted bilaterally. Which of the sets of lab values shown in Figure A would most likely be seen in this patient?

Answer: C

Explanation:
This patient is presenting with symptoms of heart failure (CHF). The most likely laboratory abnormalities are elevated brain natriuretic peptide (BNP), high anti-diuretic hormone (ADH), low sodium, and low potassium.

Heart failure is characterized by the decreased performance of the cardiac ventricles resulting in ventricular dilation. As the ventricles dilate, they release BNP as a marker of stretching of myocardial tissue. BNP levels can therefore serve as a marker of CHF. The kidneys will also have decreased perfusion levels in this disease leading to several key physiologic changes. First, is the activation of the renin-angiotensin-aldosterone system, which serves to increase perfusion to the kidneys by increasing blood pressure. This system achieves increased blood pressure by maintaining sodium and fluid retention at the expense of decreased potassium (hypokalemia) and decreased hydronium ions (metabolic alkalosis). In addition, ADH is also increased to further increase perfusion, resulting in water retention, hemodilution, and hyponatremia.

Ma et al. studied the correlation between BNP levels and cardiovascular outcomes. They found that patients with CHF and high levels of BNP had increased rates of cardiovascular complications. They recommend assessing BNP levels in patients who are suspected of having CHF.

Figure A is a chart with changes in brain natriuretic peptide, anti-diuretic hormone, sodium, and potassium that would be seen in various diseases.

Incorrect Answers:
Answer A: High BNP, high ADH, high sodium, and high potassium does not reflect the changes that would be seen in CHF. Though aldosterone serves to retain sodium, it also absorbs water. Thus, hypernatremia would not be seen. This pattern could be seen in patients with heart failure who have high free water losses such as after a burn or in desert environments.

Answer B: High BNP, low ADH, normal sodium, and low potassium does not reflect the appropriate increase in ADH and subsequent decrease in sodium that would be seen in CHF. Patients who have diabetes insipidus can have low ADH in this setting resulting in loss of free water.

Answer D: Low BNP, high ADH, low sodium, and low potassium does not reflect the finding of elevated BNP that is classically found in the dilated ventricles of CHF. This pattern would be seen in patients with the syndrome of inappropriate ADH where excessive resorption of free water results in hemodilution.

Answer E: Low BNP, low ADH, normal sodium, and normal potassium reflect the findings in a healthy patient. This patient most likely has CHF, which would result in increased aldosterone and ADH function.

Bullet Summary:
Common lab findings in heart failure include elevated BNP, elevated ADH, low sodium, and low potassium.


Question: A 62-year-old man presents to the emergency department with chest pain and shortness of breath that he experienced while barbecuing. The pain is over his chest and in his left arm. The patient has a medical history of obesity, type 2 diabetes mellitus, and hypertension. His current medications include insulin, metformin, lisinopril, and hydrochlorothiazide. An ECG is performed and is seen in Figure A. His temperature is 99.5°F (37.5°C), pulse is 112/min, blood pressure is 100/70 mmHg, respirations are 18/min, and oxygen saturation is 95% on room air. The patient is appropriately managed and is admitted to the step-down unit. 2 days later, he complains of chest pain. A repeat ECG is performed and is seen in Figure B. Which of the following is the most appropriate next step in management for this patient's underlying condition?

Answer: Aspirin

Explanation:
This patient is presenting with chest pain several days after sustaining a myocardial infarction and has an ECG suggestive of pericarditis. This presentation is consistent with Dressler syndrome and the most appropriate initial step in management is aspirin.

Dressler syndrome is pericarditis that can occur after a myocardial infarction (MI). It most commonly occurs weeks to months after the MI, but can also occur within 1 week from an MI in rare cases. It is believed to result from an autoimmune reaction that occurs after damage to the heart (surgery and MI). It presents with chest pain, fever, pleuritic pain, and a pericardial friction rub. ECG demonstrates diffuse ST elevation with PR depression consistent with pericarditis. The most appropriate initial step in the management of this condition is symptomatic management with aspirin.

Leib et al. review the evidence regarding the diagnosis and treatment of Dressler syndrome. They discuss how this condition is secondary pericarditis with or without pericardial effusion resulting from injury to the heart or pericardium. They recommend considering this syndrome in all patients with chest pain after a myocardial infarction.

Figure/Illustration A demonstrates an ECG with ST elevation in leads II, III, and aVF (blue circles) suggesting a diagnosis of right-sided MI.

Figure/Illustration B demonstrates an ECG with diffuse ST elevation and PR depression (blue circles) suggesting a diagnosis of pericarditis.

Incorrect Answers:
Answers 1 & 5: Angiography and stenting would be appropriate management if this patient were experiencing a repeat MI. The diffuse ST elevation and PR depression seen several days after his myocardial infarction are more indicative of pericarditis rather than a repeat MI. In addition, the chest pain the patient is experiencing can also occur in pericarditis and obfuscates the diagnosis of repeat MI.

Answers 3 & 4: Ibuprofen, other NSAIDs, and corticosteroids such as prednisone are not first-line therapy in post-MI pericarditis as they can hinder the healing and remodeling process of the myocardium. Current guidelines dictate that they may be used in cases that are refractory to initial therapy.

Bullet Summary:
Dressler syndrome (post-MI pericarditis) presents with chest pain, pericardial friction rub, fever, and diffuse ST elevation with PR depression on ECG, and should be treated initially with aspirin.


Question:
An 18-year-old man presents to his primary care provider with his parents for a sports physical. He was last seen in the clinic several months ago when he was diagnosed with attention deficit hyperactivity disorder (ADHD). He was started on methylphenidate at that time and the patient now reports improvement in his ability to concentrate in school and at home. He hopes to play baseball in college and has begun lifting weights daily in preparation for baseball season. The patient has a healthy diet to fuel his exercise regimen. His parents have no concerns and are pleased with the recent improvement in his grades. His temperature is 98.6°F (37°C), blood pressure is 115/71 mmHg, pulse is 72/min, and respirations are 12/min. On physical exam, the patient has tall stature with average muscle mass for his age. He has no dysmorphic features. His chest has a normal appearance other than mild gynecomastia. The patient has sparse facial hair and a moderate amount of coarse pubic hair that extends across the pubis and spares the medial thighs. His testes are small and firm. Laboratory testing is performed and reveals the following:

Follicle-stimulating hormone (FSH): 42 mIU/mL
Luteinizing hormone (LH): 38 mIU/mL

Which of the following is the most likely etiology of this patient’s presentation?

Answer: Meiotic nondisjunction

Explanation:
This patient presents with tall stature, gynecomastia, and small testes with elevated FSH and LH, which suggests a diagnosis of Klinefelter syndrome. Klinefelter syndrome is usually caused by meiotic nondisjunction that results in a 47,XXY genotype.

Klinefelter syndrome is the most common cause of primary hypogonadism. Patients with Klinefelter syndrome present with tall stature, neurocognitive difficulties (ADHD), and features of hypogonadism including gynecomastia, small testes, small phallus, hypospadias, underdeveloped secondary sex characteristics, and cryptorchidism. Patients without hypospadias or cryptorchidism are often not diagnosed until after puberty when the symptoms of gynecomastia and small testes become more prominent. Because the hypogonadism in Klinefelter syndrome is caused by testicular fibrosis, laboratory results demonstrate low testosterone and elevated FSH and LH levels. Treatment for this condition includes androgen replacement therapy.

Lanfranco et al. review the evidence regarding the treatment of Klinefelter syndrome. They discuss how modern fertility augmentation therapy has allowed some of these patients to produce viable offspring. They recommend having a detailed discussion with these patients and their partners regarding possible outcomes.

Incorrect Answers:
Answer A: Anabolic steroid use causes decreased levels of FSH and LH due to the suppression of GnRH release by the hypothalamus. This results in decreased FSH and LH release by the pituitary gland. Anabolic steroid use would not present with signs of hypogonadism.

Answer B: The CGG trinucleotide repeat disorder characterizes fragile X syndrome. Fragile X presents with macroorchidism rather than hypogonadism and patients typically have dysmorphic features of a long, narrow face with large ears, a prominent forehead, and a prominent chin. Fragile X is the most common cause of inherited intellectual disability.

Answer C: The CTG trinucleotide repeat disorder characterizes myotonic dystrophy. Although myotonic dystrophy presents with hypogonadism, patients would also present with symptoms of progressive weakness, such as facial weakness, dysphagia, or hand grip weakness. Treatment is with cardiac pacemakers and ventilatory support.

Answer D: Failure of neuronal migration characterizes Kallmann syndrome. Kallmann syndrome presents with the classic symptoms of anosmia and hypogonadism, but patients with Kallmann syndrome have a low FSH and LH. Treatment is with hormone replacement therapy.

Bullet Summary:
Klinefelter syndrome results in primary hypogonadism and presents with tall stature, gynecomastia, small testes, a small phallus, hypospadias, and cryptorchidism.


Question: A 25-year-old man presents to his primary care physician with a chief complaint of "failing health." He states that he typically can converse with animals via telepathy but is having trouble right now due to the weather. He has begun taking an assortment of Peruvian herbs to little avail. Otherwise, he is not currently taking any medications. The patient lives alone and works in a health food store. He states that his symptoms have persisted for the past 8 months. When obtaining the patient's medical history, there are several times he attempts to telepathically connect with the animals in the vicinity. His temperature is 98.6°F (37°C), blood pressure is 115/71 mmHg, pulse is 72/min, and respirations are 12/min. On physical exam, you note a healthy young man who is dressed in an all-burlap ensemble. Which of the following is the most likely diagnosis?

Answer: Schizotypal personality disorder

Explanation:
This patient has several odd and eccentric beliefs without frankly psychotic features and he is able to function in society. This suggests a diagnosis of schizotypal personality disorder.

Schizotypal personality disorder presents with eccentric behavior, magical thinking, odd beliefs, and perceptual disturbances. These patients may seem to have symptoms of schizophrenia; however, they do not respond to internal stimuli and do not experience visual or auditory hallucinations. They are able to function in society and care for themselves. Patients with schizotypal personality disorder typically struggle in maintaining close relationships or making friends. Patients are typically not distressed about their thought patterns but can undergo treatment with psychotherapy if they seek to change their behaviors.

Sher reviews the evidence regarding the treatment of patients with schizotypal personality disorder. He discusses how this disorder often goes undiagnosed and is difficult to treat. He recommends providing suicide prevention measures as this disease is associated with suicidal ideation.

Incorrect Answers:
Answer A: Brief psychotic disorder presents with either visual or auditory hallucinations with symptoms that have lasted for less than 1 month. Patients have frankly psychotic features and should be closely monitored for the development of schizophrenia.

Answer B: Schizoid personality disorder presents with social isolation. These patients are alone but do not desire social contact and are content in their isolation. A typical example is an individual who works in a solitary job on the graveyard shift. Patients do not have strange or magical beliefs.

Answer C: Schizophrenia presents with either visual or auditory hallucinations with symptoms that have lasted for 6 months or longer. These patients typically have trouble caring for themselves and struggle to function in society. Though this patient is attempting to connect/communicate with animals, this likely represents an odd belief rather than responding to internal stimuli. Schizophrenia should be treated with antipsychotic medications.

Answer D: Schizophreniform disorder presents with either visual or auditory hallucinations with symptoms that have lasted for 1-6 months. Patients have symptoms with frankly psychotic features and should be treated with antipsychotic medications.

Bullet Summary:
Schizotypal personality disorder presents with eccentric behavior, magical thoughts, and odd beliefs but patients are able to function within society.


Question: A 25-year-old woman is brought to the emergency department by her family. They found her somnolent next to her computer with an empty pill bottle around 3 hours ago. The family cannot recall the types of pill bottles that they found and did not bring them to the ED. The patient's medical history is notable for anxiety, obesity, hypertension, and polycystic ovarian syndrome. She is currently not on any medications. She was given an exercise program but she has not been compliant with these exercises. Her temperature is 99.5°F (37.5°C), pulse is 82/min, blood pressure is 125/85 mmHg, respirations are 11/min, and oxygen saturation is 97% on room air. Physical exam is within normal limits. The patient begins communicating with the physician and states that she did take acetaminophen but it was only a few pills. Her parents are certain the bottle was new. Which of the following is the most appropriate next step in management?

Answer: N-acetylcysteine

Explanation:
This patient is presenting with acute acetaminophen intoxication. The most appropriate next step in management is to administer the antidote N-acetyl cysteine (NAC).

In a toxicology case where the ingestion is unknown, the most appropriate initial step in management is to begin treatment empirically with IV fluids, charcoal, NAC, naloxone, and glucose if needed. These agents are effective against the most common causes of intoxication. In cases where there is known acetaminophen ingestion, the most important treatment is prompt administration of NAC. This medication works by increasing the hepatic production of glutathione, which detoxifies the toxic metabolite of acetaminophen N-acetyl-p-benzoquinone imine (NAPQI). NAC is a safe, cheap, and effective treatment that could be life-saving if administered in a timely fashion. In massive overdoses, it is appropriate to start treatment empirically as it can be discontinued later. Otherwise, a 4 hour acetaminophen level should be collected and the level should be plotted on the Rumack Matthew nomogram to determine treatment. In chronic acetaminophen toxicity, the acute serum level play no role in guiding treatment.

Chiew et al. performed a meta-analysis regarding the treatment of acetaminophen overdose. They found that the administration of charcoal immediately after ingestion can decrease the rate of absorption of acetaminophen. They recommend early administration of N-acetyl cysteine in order to decrease the hepatotoxicity of this substance.

Incorrect Answers:
Answer A: Blood acetaminophen levels should be ordered, but it is much less dire to confirm the diagnosis than it is to begin treatment given the high fatality rate with untreated acetaminophen overdose. Testing for all common intoxication should proceed while treatment is being administered. In this case, the concern for consumption of an entire bottle of acetaminophen would make it reasonable to treat first.

Answer B: Charcoal is an appropriate intervention if it is given in a timely manner; however, this patient consumed acetaminophen over 2 hours ago. In general, if the patient's airway is secure, it does no harm and could offer some benefit by decreasing the absorption of the substance of interest.

Answer C: IV fluid administration is the most appropriate initial step in the management of trauma when there is suspected bleeding and vitals are unstable (hypotension and tachycardia). Fluids are not urgently needed in this toxicity case with a patient who has stable vitals.

Answer E: Syrup of ipecac induces emesis in patients and was previously used in an attempt to have the patient vomit the toxic substance. This is no longer a preferred method of managing toxicities as patients can aspirate the vomitus or the toxic substance can induce more tissue damage during vomiting. In general, syrup of ipecac is the wrong answer choice for all toxicity cases.

Bullet Summary:
Acetaminophen toxicity should be treated immediately with N-acetyl cysteine followed by further diagnostic workup including serum acetaminophen levels.


Question: A 35-year-old man presents to his primary care physician with pain along the bottom of his foot. The patient is a long-time runner but states that the pain has been getting worse recently. When running and at rest he has a burning and aching pain along the bottom of his foot that sometimes turns to numbness. Taking time off from training does not improve his symptoms. The patient has a medical history of surgical repair of his Achilles tendon, ACL, and medial meniscus. He is currently not taking any medications. The patient lives with his wife and they both practice a vegan lifestyle. His temperature is 98.6°F (37°C), blood pressure is 114/72 mmHg, pulse is 81/min, and respirations are 12/min. On physical exam, the patient states that he is currently not experiencing any pain in his foot but rather is experiencing numbness/tingling along the plantar surface of his foot. Strength is 5/5 and reflexes are 2+ in the lower extremities. Which of the following is the most likely diagnosis?

Answer: Tarsal tunnel syndrome

Explanation:
This patient is presenting with pain, tingling, and numbness on the plantar surface of his foot that is not associated with exertion or rest suggesting a diagnosis of tarsal tunnel syndrome.

Tarsal tunnel syndrome occurs due to compression of the tibial nerve as it travels through the tarsal tunnel. Compression of the nerve leads to symptoms along the plantar surface of the foot which can include pain, tingling, or numbness. These symptoms can be exacerbated/triggered by tapping on the tunnel, which lies posterior to the medial malleolus. In addition, the symptoms can occur at rest or during activity and are not improved with rest. Treatment is rest, NSAIDs, properly fitted shoes/orthotics, and in refractory cases, surgical release of the tarsal tunnel.

Gould reviews the evidence regarding the diagnosis and treatment of tarsal tunnel syndrome. He discusses how this syndrome represents a collection of different entities including space-filling lesions and local inflammation. He recommends definitive diagnosis prior to surgical treatment given that the syndrome is often misdiagnosed.

Incorrect Answers:
Answer A: Common fibular nerve compression typically occurs when there is trauma/compression just inferior to the head of the fibula. This can occur when an individual wears work boots and after fractures of the fibular neck. Symptoms of common fibular nerve compression include foot drop and numbness on the dorsum of the foot. Treatment is with activity modification and a foot orthosis to prevent an equinus contracture.

Answer B: Herniated disc presents with symptoms of radiculopathy including pain that travels down the leg through the toes. Symptoms are worsened with flexion of the leg such as during the straight leg raise test. Treatment is with NSAIDs and corticosteroid injections with surgical decompression of the disc in refractory cases.

Answer C: Plantar fasciitis can present very similarly to tarsal tunnel syndrome with pain along the plantar surface of the foot. The pain is typically exacerbated by activity and improves with rest in contrast to this patient. In addition, there is an absence of burning, pain, and numbness that occur in tarsal tunnel syndrome. Tenderness will be at the medial insertion of the plantar fascia into the calcaneal tuberosity. Treatment is conservative with NSAIDs and activity modification.

Answer E: Vitamin B12 deficiency could present with symptoms of peripheral neuropathy. This is possible given this patient's vegan diet. This patient has pain only in one of his feet and he does not have symptoms of anemia such as fatigue or pallor. Treatment is with the repletion of vitamin B12.

Bullet Summary:
Tarsal tunnel syndrome presents with pain, numbness, tingling, and aching along the plantar surface of the foot that is not associated with activity.


Question:
A 23-year-old woman presents to the emergency department complaining of a worsening headache. The headache started 1 month ago. It is constant and “all over” but gets worse when she is lying down or in the setting of bright lights. A review of systems is significant for a low-grade fever, night sweats, cough, malaise, poor appetite, and unintentional weight loss of 12 pounds in the last 2 months. The patient is sexually active with multiple male partners and reports inconsistent condom use. She has a history of intravenous drug use and has not been to a doctor in the last 2 years. Her temperature is 100.4°F (38.0°C), blood pressure is 110/78 mmHg, pulse is 88/min, and respirations are 14/min with an oxygen saturation of 98% O2 on room air. On physical exam, pain is elicited upon passive flexion of the patient’s neck. A CT scan shows ventricular enlargement. A CD4+ count is 57 cells/µL blood. A lumbar puncture is performed with the following findings:

Cerebrospinal fluid:
Opening pressure: 210 mmH2O
Glucose: 32 mg/dL
Protein: 204 mg/dL
India ink stain: Positive

Leukocyte count and differential:
Leukocyte count: 200/mm^3
Lymphocytes: 100%
Red blood cell count: 2/mm^3

Which of the following treatments most directly addresses the underlying cause of this patient's symptoms?

Answer: Amphotericin B and 5-flucytosine

Explanation:
The patient with a history of unprotected sex and intravenous drug use who presents with sub-acute fever, meningismus, photophobia, a low CD4+ count, and a positive India ink-stained lumbar puncture most likely has cryptococcal meningitis. Acute treatment for cryptococcal meningitis is intrathecal amphotericin B and 5-flucytosine.

Cryptococcal meningitis is the most common fungal meningeal infection in patients with HIV, especially those with a CD4+ count < 100/mm^3. Symptoms are normally gradual in onset and can include headache, fever, neck stiffness, and photophobia. The most appropriate initial test is a lumbar puncture with an India ink stain. Cerebrospinal fluid in fungal meningitis would have low glucose, elevated protein, and an elevated lymphocyte-dominant leukocyte count. The most accurate diagnostic test is latex particle agglutination. Intrathecal amphotericin B and 5-flucytosine are the first-line treatments for acute management. Once the patient is treated, fluconazole is given for life or until the patient’s CD4+ count is > 100/mm^3.

Badali et al. present a case of a patient with cryptococcal meningitis. They discuss how despite immediate antifungal therapy, the patient died due to a rapidly progressive infection. They recommend aggressive intrathecal therapy to treat this disease.

Incorrect Answers:
Answer A: Acyclovir is used to treat Herpes simplex virus encephalitis. Cerebrospinal fluid would show normal protein and glucose, an elevated lymphocyte-dominant leukocyte count, and an elevated red blood cell count. The Herpes virus can lead to a hemorrhage of the temporal lobes.

Answer C: Dexamethasone is given in addition to IV antibiotics if Streptococcus pneumoniae meningitis is suspected. This is the most common cause of meningitis in adults, elderly, and asplenic patients, and can spread to cause sinusitis, otitis media, or bacteremia.

Answer D: Fluconazole is used for prophylaxis against cryptococcal meningitis after a person is treated acutely. It is either given for life, or until the patient’s CD4+ count is > 100/mm^3. This treatment is not sufficient for patients with acute meningitis with neurological changes.

Answer E: Vancomycin and ceftriaxone are given to a patient suspected of having bacterial meningitis until culture results confirm the bacterial organism. Bacterial meningitis would have decreased glucose, elevated protein, and an elevated neutrophil-dominant leukocyte count.

Bullet Summary:
Cryptococcal meningitis classically presents in a patient with a CD4+ count < 100/mm^3 and should be treated acutely with intrathecal amphotericin B and 5-flucytosine.


Question: A 16-year-old boy presents to his primary care physician for a routine follow-up visit. He feels disappointed because his voice has not changed. He is concerned that he is not as tall as his classmates. He denies any headache, vision changes, nausea, or vomiting. He recently started playing for his high school basketball team and generally eats healthy food. He has no significant medical history and takes no medications. His temperature is 98.6°F (37.0°C), blood pressure is 115/70 mmHg, pulse is 70/min, and respirations are 12/min. On physical examination, the patient does not have facial hair or acne. His height is 60 inches and his arm span is 50 inches. His visual fields are full and he has no cranial nerve abnormalities. His strength is 5/5 in bilateral upper and lower extremities. Chest palpation and abdominal examination are unremarkable. He has no pubic hair and his testicles are symmetric with a volume of 3 mL. Which of the following is the most appropriate next step in management?

Answer: Radiograph of the hand and wrist

Explanation:
This patient is greater than 14 years of age without the development of secondary sex characteristics (e.g., testicular volume < 4 mL), which is concerning for delayed puberty. The patient should have a radiograph of the hand and wrist to evaluate for discrepancies between bone age and chronological age.

Delayed puberty in boys is defined as the absence or incomplete development of secondary sexual characteristics (increased testicular volume and pubic hair) at 14 years or older. It has a variety of etiologies including chromosomal abnormalities, gonadotropin-releasing hormone (GnRH) deficiencies, and constitutional delay of puberty. In addition to obtaining a history and physical examination, initial diagnostic studies used to work up delayed puberty includes a radiograph of the hand and wrist to determine bone age, and serum studies (complete blood count, complete metabolic panel, follicular-stimulating hormone [FSH], luteinizing hormone [LH], and testosterone). Radiography can compare the patient's bone age to the chronological age (as constitutional delay presents with delayed bone age), and serum endocrine studies can help distinguish between primary causes of hypogonadism (high FSH and LH) and secondary causes of hypogonadism (low to normal FSH and LH). Treatment in cases with a specific cause of delayed puberty is aimed at the underlying cause. For male patients with presumed constitutional delay of puberty, therapy can include hormone replacement with testosterone.

Saengkaew et al. discuss the genetics of pubertal delay. The authors find that pathologic mechanisms that may underlie constitutional delay of puberty are largely related to GnRH neuronal development and biology. The authors recommend further study of GnRH neuronal biology and network functionality to provide the opportunity for improved therapies for patients with disorders of puberty.

Incorrect Answers:
Answer A: Karyotyping is a useful diagnostic study in patients with Klinefelter syndrome, which would demonstrate 47, XXY. Patients would present with a eunuchoid habitus (arm span at least 5 cm longer than height), gynecomastia, and testicular atrophy.

Answer B: Magnetic resonance imaging (MRI) of the brain with gadolinium is a useful diagnostic study in patients with neurological symptoms in addition to hypogonadism. These symptoms would suggest that the patient has a prolactinoma causing impingement of the optic chiasm leading to bitemporal hemianopsia and sometimes a headache. Laboratory studies consistent with a prolactinoma include elevated serum prolactin with low to normal FSH and TSH.

Answer C: Reassurance with close follow-up would be appropriate in some patients with constitutional delay of puberty, which is the most common cause of delayed puberty. It is believed to be caused by a transient defect in the production of GnRH. Patients typically have a family history of "late bloomers," characterized as family members having a late growth spurt or late puberty.

Answer E: Testicular ultrasound would be appropriate in patients with asymmetric testicles since gonadal tumors can occur in a number of intersex disorders (e.g., androgen insensitivity syndrome) and present with impaired sexual maturation.

Buller Summary:
Delayed puberty in boys is defined as a lack of testicular enlargement by age 14 and initial diagnostic evaluation should include radiography of the hand and wrist as well as serum testing (FSH, LH, and testosterone).


Question: A 65-year-old man presents to his primary care physician for stiffness in his arm. He has been having trouble combing his hair and reaching objects that are high on the shelf. The patient has a medical history of type 2 diabetes mellitus, obesity, and hypertension. His current medications include metformin, insulin, lisinopril, and hydrochlorothiazide. The patient leads a sedentary life in which he tends to stay home and watch television. He does not engage in any physical or strenuous activity. His temperature is 98.6°F (37°C), blood pressure is 138/85 mmHg, pulse is 75/min, and respirations are 12/min. On physical exam, the patient has decreased passive and active range of motion of his shoulder. The strength of the patient's upper extremity is 4/5 limited by pain. Which of the following is the most likely diagnosis?

Answer: Adhesive capsulitis

Explanation:
This patient is presenting with stiffness and a decreased range of motion in his shoulders suggestive of a diagnosis of adhesive capsulitis.

Adhesive capsulitis classically presents in elderly, sedentary patients with a chief complaint of stiffness. On physical exam, the key findings are a loss of active, but more importantly, passive range of motion. It is the loss of passive range of motion that suggests a diagnosis of adhesive capsulitis over rotator cuff injuries, biceps tendinopathy, glenohumeral osteoarthritis, and subacromial bursitis. The diagnosis of adhesive capsulitis is made clinically; however, radiography, MRI, and ultrasound can be used to rule out other diagnoses. Treatment includes NSAIDs and physical therapy and can include steroids.

Ramirez reviews the evidence regarding the diagnosis and treatment of adhesive capsulitis. He discusses how non-operative management consists of nonsteroidal anti-inflammatory drugs, short-term oral corticosteroids, intra-articular corticosteroid injections, and physiotherapy. He recommends manipulation under anesthesia and arthroscopic capsule release in patients who fail conservative management.

Incorrect Answers:
Answer B: Biceps tendinopathy presents with pain and weakness overlying the long head of the biceps tendon. This tendon runs in the intertubercular groove on the anterior aspect of the proximal humerus. Patients will often present with pain with resisted flexion of the elbow. Treatment is surgical debridement in patients who fail conservative measures.

Answer C: Glenohumeral osteoarthritis presents with vague and diffuse pain that is exacerbated by activity in addition to a loss of range of motion of the shoulder. Though this patient is experiencing a decreased range of motion, the decreased passive range of motion is more specific for adhesive capsulitis. Treatment is with a total shoulder replacement in patients who fail conservative measures.

Answer D: Rotator cuff impingement presents with pain and weakness of the upper extremity, but also can present with a decreased range of motion as this patient experienced. Of note, the passive range of motion will not be significantly affected by this disease. Treatment is with surgical reconstruction or debridement of the rotator cuff if initial measures fail.

Answer E: Subacromial bursitis presents with localized tenderness, decreased range of motion, pain with motion, and sometimes erythema/edema. Though this patient is experiencing a decreased range of motion and pain with motion, the decreased passive range of motion suggests a diagnosis of adhesive capsulitis. Treatment is with rest and oral anti-inflammatory medications.

Bullet Summary:
Adhesive capsulitis presents with pain and a decreased passive and active range of motion.


Question: A 32-year-old G1P0 presents to the antenatal testing unit at 32 weeks of gestation for a non-stress test (NST). Yesterday she had several episodes of diarrhea and vomited once after attending a company picnic 2 days ago. She took loperamide with symptomatic relief. She is worried that she is dehydrated but otherwise feels well and has recovered from her gastrointestinal illness. The patient was diagnosed with gestational diabetes after routine screening in the 2nd trimester and has been started on insulin after unsuccessful attempts at lifestyle management. She also has migraines and gastroesophageal reflux disorder. The patient has a 15-pack-year smoking history but quit smoking in her 1st month of pregnancy. She denies alcohol or drug use. Her temperature is 98.5°F (36.9°C), blood pressure is 122/82 mmHg, pulse is 84/min, and respirations are 14/min. A representative portion of the NST is shown in Figure A. Which of the following is the most likely explanation for this patient’s non-stress test (NST) results?

Answer: Fetal sleep cycle

Explanation:
This patient presents with a nonreactive NST on routine testing. The most common explanation for a nonreactive NST is the fetal sleep cycle.

Patients with gestational diabetes are at increased risk of fetal demise and other perinatal complications. They require closer monitoring during the 3rd trimester of pregnancy. The NST, which lasts 20 minutes, is the most common method of doing so. After 32 weeks, a reactive (i.e. “normal”) NST requires at least 2 episodes of 15-beat-per-minute accelerations lasting for at least 15 seconds. An NST with no accelerations is considered nonreactive. A common cause of a nonreactive NST is the fetal sleep cycle and it is reasonable to continue the test for an additional 20 minutes to increase the chance of monitoring the fetus while awake. Otherwise, a nonreactive NST should prompt vibroacoustic stimulation or further testing such as a biophysical profile (BPP).

Umana and Siccardi review the evidence regarding the use of the NST during pregnancy. They discuss how the test is a measurement of fetal cardiovascular function at the time of the test. They recommend monitoring the baseline fetal heart rate and variability as well as the presence of accelerations and decelerations when interpreting test results.

Figure/Illustration A shows a representative portion of a NST where the fetal heart rate remains within a narrow band without accelerations (red circle). This pattern is characteristically seen in a nonreactive NST that can be due to the fetal sleep cycle.

Incorrect Answers:
Answer B: Maternal dehydration generally should not affect the reactivity of an NST. Although severe dehydration may reduce amniotic fluid volume and therefore increase the baseline fetal pulse, it is unlikely to change the accelerations or variability in an NST. Though this patient had diarrhea the day before, her pulse is not elevated and any dehydration is probably not clinically significant.

Answer C: Maternal medication use can cause nonreactivity on an NST if drugs such as morphine or other sedatives are taken. Although this patient did take loperamide (an opioid), it is unlikely that this has a sedative effect on the fetus as it acts selectively on the mu-opioid receptors in the large intestine and does not cross the blood-brain barrier.

Answer D: Maternal smoking in close proximity to an NST has been linked to nonreactivity, but this patient has not smoked in several months. Mothers who smoke are counseled to avoid smoking on the day of their NST to avoid the effects of nicotine on their test results.

Answer E: A normal result is known as a reactive NST and would present with accelerations and no concerning or late decelerations. This is not a reactive NST due to the lack of appropriate accelerations.

Bullet Summary:
The most common cause of a non-reactive non-stress test is the fetal sleep cycle.


Question: A 34-year-old nulliparous woman presents to the clinic with 2 weeks of copper-colored discharge from her right nipple. Her breast has not been tender, and she has not noticed any changes to the skin. She is otherwise healthy and does not take any medications. Her temperature is 36.5°C (97.7°F), blood pressure is 110/82 mmHg, pulse is 68/min, respirations are 12/min, and oxygen saturation is 99% on room air. Exam of the right breast reveals no mass on palpation. Bloody discharge is expressed from the right nipple. There is no axillary lymphadenopathy. Which of the following is the most likely diagnosis?

Answer: Intraductal papilloma

Explanation:
This young patient who presents with non-painful unilateral bloody nipple discharge and no palpable mass on breast exam most likely has an intraductal papilloma.

Intraductal papilloma is a benign epithelial tumor that develops in the lactiferous ducts of the breast and is the most common cause of bloody nipple discharge in premenopausal women. Patients typically present with painless unilateral bloody nipple discharge, and often there is no mass palpable on breast exam. Ultrasound is the initial method for evaluation and may reveal an intraductal mass, but if results are inconclusive, further imaging with mammography is indicated. If the results of both still remain inconclusive, galactography (radiography after injecting radiopaque contrast into the duct system) is the most accurate imaging method for diagnosing intraductal papilloma. A core biopsy of the intraductal mass should be obtained, and if results show papilloma with atypia, treatment would be surgical excision of the involved duct to rule out a concomitant malignant neoplasm.

Khan et al. review the treatment of intraductal papilloma and note that in lesions with core biopsy showing papilloma with atypia, surgical excision revealed the diagnosis of a concomitant invasive or ductal in situ cancer is common. The authors also find that in patients whose core biopsies showed papilloma without atypia, the likelihood of cancer was much lower. The authors recommend that since the diagnosis of intraductal papilloma carries an increased risk of breast cancer compared to the general population, these patients should be monitored accordingly.

Incorrect Answers:
Answer A: Ductal carcinoma in situ (DCIS) is a neoplastic lesion confined to the breast duct that if untreated develops into invasive ductal carcinoma. Typically, patients are asymptomatic, and lesions are detected via screening mammography. Though it can sometimes present with nipple discharge, this is less common. Unilateral painless bloody nipple discharge is more likely to be due to intraductal papilloma, though no mass may be palpable for either diagnosis.

Answer C: Invasive ductal carcinoma is the most common type of breast cancer, which typically presents as a firm, immobile, painless lump in the breast, sometimes associated with nipple discharge, overlying skin changes, inverted nipple, and/or axillary lymphadenopathy. As with DCIS, nipple discharge may be present but is usually not bloody as in cases of intraductal papilloma.

Answer D: Mammary duct ectasia is a benign condition in which a milk duct in the breast widens and its walls thicken, leading to blockage and build-up of fluid in the duct. This is usually asymptomatic but can present with off-white or greenish nipple discharge. It may also result in infection of the affected duct, leading to periductal mastitis and a tender, erythematous breast. It tends to occur in perimenopausal women and often resolves without treatment, though if symptoms persist it can be treated with antibiotics and duct excision.

Answer E: Paget disease of the breast often presents as a scaly, raw, vesicular, or ulcerated lesion that begins on the nipple and then spreads to the areola, sometimes associated with bloody nipple discharge. Pain, burning, and pruritis are also common presenting symptoms. There is often an underlying breast carcinoma; thus, any patient with Paget disease should be evaluated with a mammogram. Although this patient has bloody nipple discharge, she does not present with a painful, scaly, raw, or vesiculated lesion that would be concerning for Paget disease of the breast.

Bullet Summary:
Intraductal papilloma often manifests in patients as painless unilateral bloody nipple discharge, and typically no mass is palpable on exam.


Question:
A 6-year-old boy presents to the emergency department after falling from his scooter. He has dull, aching pain along his left side where he hit the ground. He fell sideways off the scooter as he rounded a curve in the road. He has never had any serious injuries but that he always seems to bruise easily, especially after he started playing soccer this fall. His parents deny that he has an abnormal number of nosebleeds or bleeding from the gums. They have never seen blood in his stool or urine. His mother notes that her brother has had similar problems. His temperature is 98.6°F (37°C), blood pressure is 112/74 mmHg, pulse is 82/min, and respirations are 11/min. On physical exam, the patient has extensive bruising of the lateral left thigh and tenderness to palpation. Laboratory tests are performed and reveal the following:

Hemoglobin: 14 g/dL
Hematocrit: 41%
Mean corpuscular volume: 89 µm3
Reticulocyte count: 0.8%
Leukocyte count: 4,700/mm3
Prothrombin time (PT): 13 seconds
Partial thromboplastin time (PTT): 56 seconds
Bleeding time (BT): 4 minutes

Which of the following is the most likely underlying pathophysiology?

Answer: Factor 8 deficiency

Explanation:
This young patient presents with extensive bruising following an injury, a family history of blood disorder, and a prolonged partial thromboplastin time (PTT) with a normal prothrombin time (PT) and bleeding time. These findings suggest a diagnosis of hemophilia A caused by factor 8 deficiency.

Hemophilia is a deficiency of factor 8 (hemophilia A) or factor 9 (hemophilia B). Common symptoms of hemophilia include hemarthrosis, intramuscular hematoma, and gastrointestinal or genitourinary bleeding. Laboratory testing is helpful in confirming the diagnosis, as hemophilia is characterized by an isolated prolongation of PTT without a change in PT. The factors involved in hemophilia participate only in the indirect cascade of coagulation factor activation. Similarly, since bleeding time depends only upon platelet function and not coagulation factors, hemophilia presents with a normal bleeding time. Treatment of hemophilia includes desmopressin in mild cases and factor replacement in moderate to severe disease.

Berntorp et al. present a review of the evidence regarding the diagnosis and treatment of hemophilia. They discuss how these patients now have normal life expectancies with the advent of factor replacement therapy. They recommend being vigilant for the development of anti-factor antibodies.

Incorrect Answers:
Answer A: Anti-platelet antibodies are responsible for idiopathic thrombocytopenic purpura (ITP). This disease is caused by autoimmune antibody formation that damages platelets and causes them to be removed by splenic macrophages in the reticuloendothelial system. It usually occurs in children after an acute viral infection and it presents with bleeding from mucosal surfaces with laboratory findings showing an increased bleeding time, decreased platelets, and a normal PT/PTT.

Answer C: Factor 9 deficiency (hemophilia B) presents nearly identically to hemophilia A with a normal PT, prolonged PTT, and normal bleeding time with a history of bleeding in male relatives. However, because hemophilia B is epidemiologically less common than hemophilia A, hemophilia A is a more likely diagnosis.

Answer D: GP1b deficiency causes Bernard-Soulier syndrome, which is a bleeding disorder characterized by unusually large platelets and a low platelet count. Like von Willebrand disease (vWD), patients often present with cutaneous and mucosal bleeding, abnormal bleeding from minor trauma, and a prolonged bleeding time, which this patient does not have. It can be distinguished from vWD by a ristocetin assay. Treatment can include tranexamic acid.

Answer E: Von Willebrand factor deficiency results in vWD, which is a bleeding disorder characterized by cutaneous and mucosal bleeding, menorrhagia, and gastrointestinal bleeding. Unlike this patient, patients with vWD also present with a prolonged bleeding time. Patients with vWD will also have an increased PT because this factor is responsible for stabilizing coagulation factor 8.

Bullet Summary:
Hemophilia A is caused by factor 8 deficiency and presents with hemarthrosis, frequent bruising, intramuscular hematoma, and gastrointestinal bleeding with a prolonged PTT with a normal PT and bleeding time.


Question: A 6-month-old boy is brought to the pediatrician by his parents for a routine visit. His parents report that he is feeding and stooling well and they have just started experimenting with solid foods. His parents are concerned because a few weeks ago he started rolling from back to front in addition to front to back, but he now struggles when placed on his back. The patient was noted to be developmentally appropriate for his age at his last visit 2 months ago. On physical exam, the patient seems well-nourished and has no dysmorphic features. His temperature is 98.6°F (37°C), blood pressure is 77/49 mmHg, pulse is 112/min, and respirations are 24/min. In the examination room, he is able to roll from front to back but cannot roll from back to front. He is not able to sit without support and makes no attempt at bouncing when supported in a standing position. The patient’s abdomen is non-tender and soft without hepatosplenomegaly. His patellar reflexes are 4+ bilaterally. He is found to have the ocular finding seen in Figure A. Accumulation of which of the following would most likely be found in this patient’s cells?

Answer: GM2-ganglioside

Explanation:
This 6-month-old boy who presents with developmental regression, a “cherry-red” macula, and hyperreflexia most likely has a diagnosis of Tay-Sachs disease. Tay-Sachs disease is caused by a deficiency of beta-hexosaminidase A that results in the accumulation of GM2-ganglioside.

Tay-Sachs disease is a genetic disorder caused by an autosomal recessive deficiency of the beta-hexosaminidase A enzyme. This disease presents in infants aged 2-6 months with progressive neurodegeneration, hypotonia, feeding difficulties, and a “cherry red” spot on the macula. Tay-Sachs disease shares many features with Niemann-Pick disease; however, Niemann-Pick disease presents with the additional findings of hepatosplenomegaly and hyporeflexia whereas Tay-Sachs presents with hyperreflexia without hepatosplenomegaly. Both diseases are more common in the Ashkenazi Jewish population. There is no curative treatment for this disease so treatment is generally supportive.

Solovyeva et al. review the evidence regarding the diagnosis and treatment of Tay-Sachs disease. They discuss how this disease normally presents with muscle weakness, ataxia, speech, and mental disorders. They recommend considering novel treatments such as substrate reduction therapy.

Figure/Illustration A is a fundoscopic exam demonstrating a “cherry-red” spot on the macula (blue circle). This finding is seen in both Tay-Sachs disease and Niemann-Pick disease.

Incorrect Answers:
Answer A: Cerebroside sulfate accumulates in metachromic leukodystrophy, which is caused by an autosomal recessive deficiency in arylsufatase A. This disease presents with optic atrophy and seizures in childhood. Patients will later develop dementia, psychiatric disease, and neuropathy. There is no cure so treatment is supportive.

Answer B: Galactocerebroside accumulates in Krabbe disease, which is caused by an autosomal recessive deficiency in galactocerebrosidase. Krabbe disease presents in early infancy with developmental regression, hypotonia, and areflexia. Treatment is supportive with musculoskeletal bracing as needed.

Answer C: Glucocerebroside accumulates in Gaucher disease, which is caused by an autosomal recessive deficiency in glucocerebrosidase. Gaucher disease presents with pancytopenia and hepatosplenomegaly. “Gaucher cells,” or lipid-laden macrophages resembling crumpled tissue paper, can be seen on histology. Treatment is with enzyme replacement therapy.

Answer E: Sphingomyelin accumulates in Niemann-Pick disease, an autosomal recessive sphingolipidosis caused by a deficiency in sphingomyelinase. Niemann-Pick disease presents with many of the same features as Tay-Sachs disease but has additional findings of hyporeflexia and hepatosplenomegaly.

Bullet Summary:
Tay-Sachs disease is caused by a deficiency of beta-hexosaminidase A resulting in the accumulation of GM2-ganglioside.


Question:
A 4-year-old boy is brought in by his grandmother for worsening seizure activity. She reports that occasionally he “suddenly drops” when running around the house. She says that his first seizure occurred 1 year ago. Since then, he has been on valproic acid but the seizure activity remains unchanged. He was recently enrolled in daycare because she could no longer care for him full-time. Since then, the seizure activity has increased and the daycare facility also noted concerns over his lack of response to voice commands. Family history is significant for a cousin who died suddenly at a young age. His temperature is 98.6°F (37°C), blood pressure is 105/52 mmHg, pulse is 110/min, and respirations are 25/min. A physical exam is significant for lack of response to auditory stimulation. An EEG is performed, which is unrevealing. An ECG is shown in Figure A. The patient is then startled when a door is closed quickly and he suddenly loses consciousness. An ECG is quickly performed and is shown in Figure B. An electrolyte panel is drawn with the following findings:

Serum:
Na+: 142 mEq/L
Cl-: 88 mEq/dL
K+: 3.4 mEq/L
HCO3-: 24 mEq/L
BUN: 11 mg/dL
Glucose: 67 mg/dL
Creatinine: 0.6 mg/dL
Mg2+: 1.7 mg/dL

Which of the following is the most appropriate next step in management?

Replete potassium and magnesium and start a beta-blocker

Answer: Replete potassium and magnesium and start a beta-blocker

Explanation:
The patient who presents with deafness and long QT syndrome that progressed to torsades de pointes most likely has Jervell and Lange-Nielsen syndrome. The most appropriate next step in management is to replete potassium and magnesium and then start a beta-blocker.

Jervell and Lange-Nielsen syndrome is an autosomal recessive disorder caused by defective potassium ion channels. This causes abnormal function of the inner ear resulting in congenital sensorineural deafness as well as abnormal myocardial conduction resulting in long QT syndrome. A prolonged QT interval increases the risk of ventricular dysrhythmias, especially torsades de pointes, which may manifest as syncope, or sudden death. These episodes are usually triggered by exertion or by being startled. Management of symptomatic congenital long QT syndromes or torsades de pointes should involve the repletion of potassium and magnesium as well as the initiation of a beta-blocker medication. If symptoms are refractory to beta-blockers, a pacemaker can be implanted to avoid cardiac arrest.

Adam et al. review the evidence regarding the diagnosis and treatment of Jervell and Lange-Nielsen syndrome. They discuss how a beta blocker medication should be used for medical control of this syndrome. They recommend pacemaker placement in refractory cases.

Figure/Illustration A is an ECG showing a prolonged QT interval (blue lines). This interval can be prolonged due to certain medications such as ondansetron or it can be due to long QT syndrome, which may be acquired or congenital.

Figure/Illustration B is an EKG showing a polymorphic ventricular tachycardia with varying QRS complex amplitudes over time (blue curve). This feature where the QRS complexes appear to “twist” around the isoelectric line is seen in torsades de pointes.

Incorrect Answers:
Answer A: IV lorazepam is the medical treatment for pediatric status epilepticus. Status epilepticus is a seizure that lasts for greater than 5 minutes or recurrent seizures with no return to baseline. This patient has an ECG showing torsades de pointes, which explains his sudden loss of consciousness as well as a normal EEG.

Answer B: A pacemaker can be used to treat refractory dysrhythmias caused by Jervell and Lange-Nielsen syndrome, but would not be the initial step in management for this patient. Beta-blocker medications should be used prior to pacemaker placement.

Answer D: While potassium and magnesium should be repleted, procainamide is a class 1A anti-arrhythmic medication that prolongs the QT interval. This class of medication is contraindicated in patients with long QT syndrome or torsades de pointes.

Answer E: Ethosuximide is used to treat absence seizures. The loss of consciousness associated with Jervell and Lange-Nielsen syndrome can be mistaken for absence seizures, but the patient's prolonged QT interval on ECG makes Jervell and Lange-Nielsen syndrome the most likely diagnosis. Of note, valproic acid is also a medication for absence seizures.

Bullet Summary:
Jervell and Lange-Nielsen syndrome should be treated with repletion of potassium and magnesium as well as initiation of beta-blocker medication with pacemaker placement reserved for refractory cases.


Question: A 67-year-old man presents to the emergency department with shortness of breath. His dyspnea began 1 hour ago while he was sitting in a chair watching television. He also endorses lightheadedness and fatigue but denies chest pain. Two weeks ago, he had a mitral valve repair for mitral insufficiency secondary to myxomatous degeneration. His medical history is otherwise significant for hypertension and diabetes mellitus, for which he takes metformin and lisinopril. His temperature is 98.8°F (37.1°C), blood pressure is 85/54 mmHg, pulse is 48/min, and respirations are 22/min. On physical exam, he appears to be in moderate distress. He has normal cardiac sounds with an irregular rhythm. His lungs are clear to auscultation bilaterally, and his electrocardiogram can be seen in Figure A. The patient is given an initial dose of atropine but this has no effect. Which of the following is the most appropriate next step in management?

Answer: Transvenous pacing

Explanation:
This patient who presents with lightheadedness has an ECG consistent with a Mobitz type 2 2nd-degree heart block. Because the patient is symptomatic from his dysrhythmia and it did not respond to atropine, the most appropriate next step is transvenous pacing.

Mobitz type 2 2nd-degree heart block can be distinguished from Mobitz type 1 (Wenckebach) by the length of the PR interval. Whereas the PR interval in Mobitz type 1 becomes progressively longer with each beat, the PR intervals in Mobitz type 2 are consistent in length and the QRS complexes drop suddenly. While Mobitz type 1 heart block is usually caused by atrioventricular (AV) node dysfunction, Mobitz type 2 is caused by dysfunction below the AV node in the His-Purkinje system. Patients with either type of heart block can present with lightheadedness or syncope. Since this pattern has a risk of progressing into 3rd-degree heart block, hemodynamic compromise, and asystole, Mobitz type 2 heart block is an indication for placement of a permanent pacemaker. Unstable patients who do not respond to atropine and/or other medical management should undergo transcutaneous or transvenous pacing.

Clark and Prystowsky present the pathophysiology of heart block. They discuss how dysfunction at the infranodal level leads to type 2 2nd-degree heart block. They recommend pacing in symptomatic patients.

Figure/Illustration A is an ECG that is characterized by consistent PR intervals (red lines) and sudden drops in the QRS complex. This pattern is classically seen with a Mobitz type 2 2nd-degree heart block.

Incorrect Answers:
Answer A: Adenosine can be used to terminate supraventricular tachycardia. These patients will present with tachycardia rather than bradycardia and will experience palpitations in addition to lightheadedness. The rhythm is rapid and regular with a narrow QRS complex.

Answer C: Cardioversion can be used to convert atrial flutter, atrial fibrillation, stable monomorphic ventricular tachycardia, or recalcitrant supraventricular tachycardia (non-responsive to adenosine or vagal maneuvers) to sinus rhythm, but it is not used for 2nd-degree heart block.

Answer B: Atropine can improve Mobitz type 1 2nd-degree heart block but tends not to be effective in Mobitz type 2 heart block in a stable patient. Atropine might be an appropriate treatment in symptomatic 3rd-degree heart block or Mobitz type 2 heart block; however, if it fails to improve a patient's symptoms, pacing is the most appropriate next step.

Answer D: Procainamide is a class 1A antiarrhythmic medication used to treat Wolff-Parkinson-White syndrome. This would present with an upgoing delta wave that occurs prior to the QRS complex. This medication does not play a role in the management of 2nd-degree heart block.

Bullet Summary:
Hemodynamically unstable patients with Mobitz type 2 2nd-degree heart block should be managed with transvenous pacing followed by a permanent pacemaker.


Question: A 32-year-old woman presents to her primary care provider with pelvic pain. She reports that for the last several years, she has had chronic pain that is worse just before her menstrual period. Over the past 2 months, she has also had worsening pain during intercourse. She denies dysuria, vaginal discharge, or vaginal pruritus. The patient has never been pregnant and previously used a copper intrauterine device (IUD) for contraception, but she had the IUD removed 1 year ago because it worsened her menorrhagia. She has now been using combined oral contraceptive pills (OCPs) for nearly 1 year. The patient reports improvement in her menorrhagia on the OCPs but denies any improvement in her pain. Her medical history is otherwise unremarkable. Her temperature is 98.0°F (36.7°C), blood pressure is 124/73 mmHg, pulse is 68/min, and respirations are 12/min. The patient has pain with lateral displacement of the cervix on pelvic exam. A pelvic ultrasound shows no abnormalities, and a urine pregnancy test is negative. Which of the following is most likely to confirm the diagnosis?

Answer: Laparoscopy

Explanation:
This patient presents with chronic pelvic pain that is worse before her menstrual period, vaginal tenderness on physical exam, and lateral displacement of the cervix, which is consistent with a diagnosis of endometriosis. Since this patient has failed therapy with oral contraceptive pills (OCPs), she should undergo laparoscopy.

Endometriosis classically presents with chronic pelvic pain and the “3 D symptoms” of dysmenorrhea, dyspareunia, and dyschezia. Since laparoscopy with biopsy is required for definitive diagnosis, patients with suspected endometriosis may be empirically managed with OCPs and NSAIDs. Most patients achieve symptom control on this regimen. If patients fail empiric therapy, have contraindications to hormonal therapy, or have severe symptoms they should undergo laparoscopy for both definitive diagnosis and treatment of the disease.

Vercellini et al. review the evidence regarding the diagnosis and treatment of endometriosis. They discuss how the diagnosis of this disorder is carried out by direct visualization and histologic examination of lesions. They recommend medical treatment for symptomatic relief and surgical excision in refractory patients.

Incorrect Answers:
Answer A: Abdominal ultrasound is less accurate than a transvaginal ultrasound which has already been performed. Since there were no findings on transvaginal ultrasound, it is unlikely that abdominal ultrasound would reveal pathology. This modality would be effective for intra-abdominal disorders such as cholelithiasis or appendicitis (in pediatric and pregnant patients to avoid radiation exposure).

Answer B: Hysterosalpingogram is more useful in the workup of infertility, particularly for patients with a history of pelvic inflammatory disease. It is not routinely used to diagnose endometriosis. Patients with pelvic inflammatory disease present with fever, purulent discharge, and cervical motion tenderness. Treatment is with antibiotics.

Answer C: Hysteroscopy is used in the workup of abnormal uterine bleeding, fibroids, and endometrial thickening or polyps. Since endometriosis is defined as endometrial glands and stroma outside of the uterine cavity, a hysteroscopy is not particularly helpful in making the diagnosis. Treatment for polyps or fibroids is with surgical excision.

Answer E: Pelvic MRI can be used to better characterize an abnormality seen on pelvic ultrasound or CT or to diagnose adenomyosis. It can aid in making the diagnosis of endometriosis but is not the most accurate/confirmatory test. A laparoscopy would both be diagnostic and therapeutic for this disorder.

Bullet Summary:
Patients with suspected endometriosis may be managed empirically with oral contraceptive pills and NSAIDs, but laparoscopy with biopsy is necessary for definitive diagnosis and management.


Question: A 26-year-old medical student presents to occupational health after sustaining a needlestick injury. She was drawing blood from an HIV-positive patient when she stuck herself percutaneously while capping the needle. She immediately washed the puncture wound with saline. The medical student has had a negative HIV serology from the beginning of medical school 2 years ago. She is monogamous with one male partner and denies any intravenous drug use. The source patient was recently diagnosed with HIV and has a CD4 count of 550 cells/µL. His most recent viral load is 1,800,000 copies/mL, and he was started on HAART 3 days ago. Which of the following is the most appropriate next step in management?

Repeat HIV serology and initiate triple antiretroviral therapy if negative

Immediately initiate triple antiretroviral therapy

Repeat HIV serology and initiate triple antiretroviral therapy if positive

Repeat HIV serology and initiate triple antiretroviral therapy immediately

Answer: Repeat HIV serology and initiate triple antiretroviral therapy immediately

Explanation:
This medical student has sustained a hollow-bore needlestick injury. The most appropriate next step is to repeat HIV serology and immediately initiate triple antiretroviral therapy with tenofovir, emtricitabine, and raltegravir.

Healthcare exposures to HIV are divided into 2 categories based on the level of contact with the source patient. If the healthcare worker’s mucous membrane or nonintact skin comes into contact with an HIV-positive patient’s blood, semen, or vaginal secretions, immediate prophylaxis is recommended. This category also includes all needlestick exposures. If the healthcare worker’s mucous membrane or nonintact skin comes into contact with an HIV-positive patient’s urine, feces, or bodily secretions, prophylaxis is not recommended. If the source patient’s HIV status is unknown, it should be assumed that the patient is HIV positive until testing proves otherwise. The triple antiretroviral drug combination of tenofovir, emtricitabine, and raltegravir is favored due to the low incidence of side effects. Prophylactic treatment should be initiated immediately (ideally within 1-2 hours) and continued for 4 weeks at which time the healthcare worker’s serology should be repeated.

Parikh et al. studied technologies for monitoring HIV infection. They discuss how high throughput methods are required in order to surveil for infection on a population level. They recommend using next-generation sequencing methods to improve surveillance methods.

Incorrect Answers:
Answer A: Immediately initiating triple antiretroviral therapy is appropriate after drawing the medical student’s HIV serology. The patient’s serology at the time of exposure must be established to compare to future testing. Despite her previous negative serology and low-risk lifestyle, it would still be best to repeat the testing at the same time prophylactic treatment is initiated.

Answer B: Perform genotype testing on source patient and initiate antiretroviral therapy tailored to results is incorrect because this option would delay the initiation of prophylaxis. Empiric treatment with a triple antiretroviral drug combination is appropriate for all patients with high-risk exposure.

Answer C: Waiting to hear that the medical student’s HIV serology is negative would delay the initiation of prophylaxis. Triple antiretroviral drug treatment should be initiated without waiting for the results. Empiric treatment of all patients with high-risk exposure is recommended in all cases.

Answer D: Waiting for the results of the medical student’s serology would delay treatment for her exposure. If her serology is already positive, she will need to be treated past the 4-week period of prophylaxis. Even though she does not engage in high-risk behaviors, a positive serology would demonstrate that she was already infected with HIV.

Bullet Summary:
After a needlestick injury from a HIV-positive source patient, a healthcare worker’s HIV serology should be drawn and they should be immediately initiated on triple antiretroviral drug therapy.


Question: A 17-year-old high school student was in shop class when he accidentally sawed off a portion of his right index finger. The teacher applied dressings and pressure to the patient's injured digit and immediately transported the patient to the emergency department. He arrived within 20 minutes of the accident. The patient has a medical history of asthma and his only medication is albuterol. His temperature is 98.0°F (36.6°C), blood pressure is 120/70 mmHg, pulse is 105/min, and respirations are 17/min. Exam was significant for pulsatile bleeding from a clean-cut wound on his right second finger. Radiography of the hand revealed a complete amputation of the right finger from the distal interphalangeal joint. The wound was cleaned, compression applied, analgesics administered, and the hand surgeons were notified. The teacher states that he left the amputated finger in the classroom, but the principal would be transporting it to the hospital. Which of the following is the correct method for transporting the amputated finger?

Rinse the finger in normal saline, wrap the finger in moist gauze, put in a plastic bag, and place the bag in ice water

Wrap the finger in moist gauze and place in a plastic bag

Rinse the finger with hydrogen peroxide, wrap the finger in moist gauze, and place on ice

Answer: Rinse the finger in normal saline, wrap the finger in moist gauze, put in a plastic bag, and place the bag in ice water

Explanation:
This patient is presenting with a fingertip amputation with loss of pulp, nail, and bone (with a possibility for surgical reattachment and repair, efforts should be made to recover the severed tissue). The correct way to transport an amputated digit is to rinse the finger in normal saline to remove gross contaminants, wrap the appendage in gauze moistened by normal saline, place it in a plastic bag, and then place the bag in ice water.

Amputation injuries are common with finger and thumb amputations being the most common. With rapid and proper transport of the patient and appendage, successful reattachment could be possible pending a surgical evaluation. It is important to know how to appropriately package the severed digit so as to optimize tissue viability. Cooling with ice water can slow the metabolic rate of the tissue and result in less tissue damage; however, there is a delicate balance. There must be proper barriers between the digit and ice water to avoid ice burns which could compromise the tissue. Patients should be given IV antibiotics to prevent infection as well.

Zhang et al. note that once a finger amputation has occurred, ischemic tolerance times are 12 hours if warm and up to 24 hours if cold. For more proximal amputations, these times are halved due to the presence of muscle tissue, which can undergo irreversible changes after 6 hours of ischemia.

Incorrect Answers:
Answer B: Rinsing the amputated finger with hydrogen peroxide could damage the tissue decreasing the chances of salvageability. Avoiding the use of caustic solutions with amputated appendages preserves tissue.

Answer C: Submerging the finger in ice water could lead to irreversible tissue damage and swelling making reattachment impossible.

Answer D: Wrapping the finger in moist gauze and then placing in a plastic bag is not enough to optimize a severed finger for transport. Cooling further with ice water is necessary in order to slow down tissue metabolism and prevent further ischemic damage.

Answer E: Wrapping the finger in moist gauze and placing it directly on ice could damage the finger by direct contact with ice rendering the amputated part non-viable.

Bullet Summary:
The correct handling of an amputated appendage is to first rinse it off with normal saline to remove any gross debris, wrap it in normal saline soaked gauze, put it in a plastic bag, and then place that bag in ice water.


Question: A 27-year-old man presents to the emergency department with altered mental status. He has become gradually more confused over the past several days. His wife also notes he has had diarrhea, nausea and vomiting, and abdominal pain for the past week. The patient has a history of depression and multiple suicide attempts. He takes fluoxetine as well as over-the-counter pain medications for a recent muscle strain. He works in a large industrial compound that manufactures semiconductors. He exercises regularly and recently has started making his own beer at home. His temperature is 98.3°F (36.8°C), blood pressure is 107/75 mmHg, pulse is 110/min, respirations are 22/min, and oxygen saturation is 99% on room air. Physical exam reveals a confused man with a garlic odor on his breath and the finding in Figure A. Cardiopulmonary exam reveals a rapid heart rate with no murmurs and clear breath sounds. Which of the following is the most likely etiology of this patient's symptoms?

Answer: Arsenic

Explanation:
This patient who works in the semiconductor industry and presents with confusion, hypotension, tachycardia, a garlic odor, and Mees lines (Figure A) most likely has arsenic poisoning.

Arsenic poisoning can occur due to exposure to contaminated drinking water, industrial jobs, insecticides, and certain preservatives. Arsenic inhibits enzymes requiring lipoic acid as a cofactor; thus, it disrupts ATP production and causes oxidative stress. Signs and symptoms of arsenic poisoning include Mees lines (white horizontal/parallel lines on the nail beds), nausea, vomiting, abdominal pain, diarrhea, confusion, hypotension, tachycardia, and a garlic odor on the breath. Severe complications are more common with acute exposures and can include shock, pulmonary edema, rhabdomyolysis, and death. Findings consistent with chronic poisoning include anemia, neuropathy, ataxia, and somnolence. A urine arsenic level can support the diagnosis. The treatment of arsenic poisoning is chelating agents such as dimercaprol and supportive therapy. Dimercaprol is a nephrotoxic chelating agent with a narrow therapeutic index and should be used with care.

Moon et al. study the association between low and moderate arsenic exposure and cardiovascular disease. The authors find that even low-dose exposure to arsenic increased the risk of cardiovascular disease, coronary artery disease, and stroke mortality. The authors recommend population-level interventions to decrease exposure to arsenic.

Figure/Illustration A is the physical exam finding of Mees lines with multiple parallel white lines in the nail bed (blue arrows).

Incorrect Answers:
Answer A: Acetaminophen overdose has a spectrum of presentations, from non-specific symptoms which can include no symptoms at all to a toxic appearance with nausea, vomiting, jaundice, and altered mental status. Patients should have a 4-hour acetaminophen level drawn. If it falls above the treatment line on the Rummack Matthew nomogram, treatment with N-acetylcysteine should be started. Acetaminophen can cause fulminant liver failure and markedly elevated liver enzymes.

Answer C: Cyanide inhibits complex IV in the electron transport chain. It can present after exposure to industrial fires. Patients may present with altered mental status and a profound lactic acidosis that does not respond to oxygen administration with rapid progression to death. The treatment involves the administration of hydroxocobalamin which combines with cyanide to form the non-toxic compound cyanocobalamin.

Answer D: Iron overdose presents with nausea, vomiting, diarrhea (bloody), hemorrhagic gastritis, and lactic acidosis. A serum iron level should be ordered to aid in diagnosis. Treatment of acute overdose includes chelation therapy with deferoxamine.

Answer E: Lead poisoning can present with constipation, irritability, lethargy, lead lines on radiography, and microcytic anemia with basophilic stippling. Treatment depends on the severity and can involve removal from exposure or chelating therapy with agents such as succimer.

Bullet Summary:
Arsenic poisoning presents with Mees lines, nausea, vomiting, abdominal pain, confusion, unstable vitals, and a classic “garlic odor.”


Question: A 13-day-old boy is brought by his mother for eye redness and ocular discharge. The mother reports that the patient has developed a cough and nasal discharge. Pregnancy and delivery were uncomplicated but the mother had limited prenatal care during the third trimester. Immediately after delivery, the baby was given silver nitrate drops and vitamin K. His temperature is 99°F (37.2°C), blood pressure is 81/52 mmHg, pulse is 135/min, and respirations are 36/min with an oxygen saturation of 98% O2 on room air. Upon visual examination of the eyes, mucoid ocular discharge and eyelid swelling are noted. A fluorescein test is negative. On lung exam, scattered crackles are appreciated. A chest radiograph is performed that shows hyperinflation with bilateral infiltrates. Which of the following is the most appropriate pharmacotherapy?

Answer: Oral erythromycin

Explanation:
This patient is presenting with mucoid ocular discharge around 2 weeks post-birth, suggesting the diagnosis of neonatal chlamydial conjunctivitis. The most appropriate treatment for this disease includes oral erythromycin.

Neonatal chlamydial conjunctivitis is caused by Chlamydia trachomatis. It presents in newborns that are 5-14 days old. Symptoms include watery or mucoid discharge and eye swelling. The conjunctiva may be especially irritated. Diagnosis can be established by direct antibody testing or PCR. Treatment for chlamydial conjunctivitis includes both topical and oral erythromycin as there is likely dissemination of the infection. The most common complication of chlamydial conjunctivitis is pneumonia. Of note, all neonates with gonococcal conjunctivitis should also be treated for chlamydia.

Smith-Norowitz et al. studied whether antibiotic prophylaxis was beneficial compared with silver nitrate for chlamydia conjunctivitis. They found that there was no benefit to topical antibiotic treatment compared with silver nitrate alone. They recommend testing infants for the disease if it is suspected so that oral antibiotics can be administered effectively.

Incorrect Answers:
Answer A: Artificial tears can be used in chemical conjunctivitis. The most common cause of neonatal chemical conjunctivitis is post-delivery silver nitrate drops. It usually presents within the first 24 hours following birth/exposure with mild conjunctival injection and tearing, and will spontaneously resolve within 2-4 days.

Answer B: Intravenous acyclovir is used to treat conjunctivitis caused by herpes simplex virus. The newborn would present between 1-2 weeks post-birth with lid edema, conjunctival injection, and non-purulent serosanguineous discharge. Corneal involvement with microdendrites or ulcers may be seen with fluorescein stain.

Answer C: Intravenous ceftriaxone is used to treat gonococcal conjunctivitis. Gonococcal conjunctivitis usually presents in newborns 0-5 days old with irritation or discharge. Patients with this disease will have very thick discharge with a purulent appearance.

Answer E: Topical erythromycin would be used to treat chlamydial conjunctivitis in conjunction with oral erythromycin; however, it is insufficient on its own. Oral erythromycin is the best answer choice for this patient as the disease has likely disseminated. Topical erythromycin can also be used as prophylaxis for gonococcal conjunctivitis.

Bullet Summary:
Neonatal chlamydial conjunctivitis presents with watery or mucoid discharge as well as eye swelling and is treated with topical and oral erythromycin.


Question:
A 26-year-old woman presents to the emergency department with 1 day of vaginal bleeding and lower abdominal pain. The pain is most pronounced in the lower abdomen and has gotten worse over the past day. Her last menstrual period was 7 weeks ago. She denies any recent abdominal or vaginal trauma. She has no other past medical history and takes no medications. She uses a copper intrauterine device and is in a monogamous relationship. Her temperature is 99°F (37.2°C), blood pressure is 79/50 mmHg, pulse is 135/min, and respirations are 20/min. Physical examination is notable for diffuse abdominal tenderness upon palpation. Pelvic examination demonstrates uterine and adnexal tenderness and uterine bleeding. Laboratory studies are shown below:

Hemoglobin: 9.5 g/dL
Leukocyte count: 6,000/mm^3
Serum beta-human chorionic gonadotropin (hCG): 2,700 IU/L

The patient is started on intravenous fluids. Which of the following is the most appropriate next step in management?

Answer: Laparoscopy

Explanation:
This patient’s acute onset abdominal pain with uterine bleeding and tenderness, positive pregnancy test, anemia, and hemodynamic instability are concerning for a ruptured ectopic pregnancy. Emergency laparoscopy is the most appropriate next step in management.

An ectopic pregnancy, due to implantation of a fertilized ovum outside the uterine cavity, most commonly in the fallopian tube, can be life-threatening if it ruptures leading to intra-abdominal hemorrhage and shock. Initial laboratory studies should include a complete blood count and a pregnancy test. A patient’s hemodynamic stability should be ascertained immediately as it determines the most appropriate next step in management. In patients who are hemodynamically unstable (hypotensive and tachycardic), a Focused Assessment with Sonography for Trauma (FAST) exam should be immediately performed to evaluate for intraperitoneal bleeding, and ob/gyn should be immediately consulted for emergent surgical intervention (e.g., salpingectomy or salpingotomy). In patients who are hemodynamically stable, transvaginal ultrasound should be performed to determine the gestational sac location, and medical therapy can be initiated (e.g., methotrexate therapy, depending on the size and location of the pregnancy).

Cheng et al. compare fertility outcomes of salpingotomy and salpingectomy in women with tubal pregnancies. The authors found that there was no difference in intrauterine pregnancy rates or repeat ectopic pregnancy rates between patients that underwent salpingotomy or salpingectomy. The authors recommend that both salpingectomy and salpingotomy are reasonable options for the surgical management of tubal pregnancies.

Incorrect Answers:
Answer A: CT of the abdomen and pelvis is useful in determining if there is an intra-abdominal hemorrhage in patients who are hemodynamically stable. Unstable patients should generally not undergo CT.

Answer C: Methotrexate therapy is an effective treatment option in patients who are hemodynamically stable. with smaller ectopic pregnancies and lower hCG levels.

Answer D: Repeat beta-hCG in 48 hours is reserved for hemodynamically stable patients with non-diagnostic findings on transvaginal ultrasound. If the beta-hCG level is below the discriminatory zone (beta-hCG level 1,500-2,500 IU/L), then it should be repeated in 48 hours.

Answer E: Transvaginal ultrasound is reserved for hemodynamically stable patients who are presenting with abnormal uterine bleeding with abdominal/pelvic pain.

Bullet Summary:
Patients who present with a ruptured ectopic pregnancy with hemodynamic instability are managed with emergent surgical intervention.


Question: A 71-year-old woman arrives to clinic with sudden vision loss. She was in her usual state of health until waking up this morning unable to see out of her right eye. She denies pain, but reports her right eye “feels funny.” The patient’s medical history is significant for a previous myocardial infarction, hypertension, and osteoporosis. Her current medications include aspirin, metoprolol, rosuvastatin, lisinopril, and alendronate. Her temperature is 98°F (36.7°C), blood pressure is 145/86 mmHg, pulse is 62/min, and respirations are 12/min with an oxygen saturation of 98% on room air. The patient's pupils are symmetric in size and equally reactive to light with accommodation. A fundoscopic exam of the right eye is shown in Figure A. The left optic fundus is unremarkable. Which of the following is the most likely diagnosis?

Answer: Retinal vein occlusion

Explanation:
This patient is presenting with sudden, painless, unilateral vision loss with a fundoscopic exam positive for venous dilation and retinal hemorrhage. These findings are consistent with the diagnosis of retinal vein occlusion.

Retinal vein occlusion can occur in either central or branch retinal veins and is often caused by compression from nearby arterial atherosclerosis. It presents as acute onset, painless vision loss, normally in one eye. On fundoscopic exam, classic findings of this disease include venous engorgement, retinal hemorrhage, cotton wool exudates, and edema/swelling of the optic disk can be seen. There is no definitive treatment for this disorder but symptomatic treatment includes intravitreal glucocorticoid injections and retinal laser photocoagulation. Retinal vein occlusion may resolve spontaneously or progress to permanent vision loss.

Robinson and Halpern present evidence regarding the treatment of retinal vein occlusion. They discuss how the treatments for the acute phase of this disease have been disappointing. They recommend managing long-term complications such as neovascularization with phototherapy.

Figure/Illustration A is a fundoscopic exam showing engorged retinal veins, optic disk swelling, and widespread retinal hemorrhages (red circle). These findings are characteristic of central retinal vein occlusion.

Incorrect Answers:
Answer A: Central retinal artery occlusion can present as sudden onset, unilateral vision loss. Fundoscopic exam will show a “cherry-red” spot at the fovea and a “fuzzy” retina with attenuated vessels. Embolic sources may include carotid artery atherosclerosis or cardiac vegetation. Treatment is with risk factor control.

Answer B: Closed-angle glaucoma presents as sudden, painful, vision loss caused by increased intraocular pressure. The eye will appear red and often feel “hard.” The optic disc will show characteristic cupping. Intraocular pressure will be levated and treatment is with acetazolamide, steroids, timolol, bromidine, and pilocarpine. Irodotomy is reserved for refractory cases.

Answer C: Papilledema may present as an enlargement in the blind spot and is usually bilateral, as it is caused by increased intracranial pressure. On fundoscopic exam, there will be bilateral optic disk swelling, seen as an elevated optic disk and blurred margins. Patients should undergo a neurologic evaluation to determine the etiology of the papilledema.

Answer D: Retinal detachment presents as monocular loss of vision, often described as a “curtain pulled down,” and preceded by “flashers” and “floaters.” On fundoscopic exam, crinkling of the retinal tissue and abrupt changes in vessel direction can be seen. Surgical reattachment of the retina is required to prevent loss of vision.

Bullet Summary:
Retinal vein occlusion presents with a sudden, monocular, painless loss of vision with optic disk swelling, dilated veins, cotton wool spots, and retinal hemorrhages.


Question: A 23-year-old woman presents to the emergency room for a self-inflicted laceration of her distal volar forearm. The patient states she knew her boyfriend was having sexual thoughts about the woman from the grocery store, prompting her decision to cut her own wrist. In the emergency department, the bleeding has stopped and the patient is currently medically stable. When interviewing the patient, she is teary and apologizes for her behavior. She is grateful to you for her care and regrets her actions. Of note, the patient has presented to the emergency department before for a similar reason when she was struggling with online dating. The patient states that she struggles with her romantic relationships though she deeply desires them. Her temperature is 98.6°F (37°C), blood pressure is 112/71 mmHg, pulse is 73/min, and respirations are 14/min. On physical exam, you note a frightened young woman who is wearing a revealing dress that prominently displays her breasts. You tell the patient that she will have to stay in the psychiatric emergency department for the night which makes her furious. Which of the following personality disorders is the most likely diagnosis?

Answer: Borderline

Explanation:
This patient is presenting with a suicide attempt, unstable relationships, and emotional lability suggesting a diagnosis of borderline personality disorder.

Borderline personality disorder classically presents with emotional lability, and intense, unstable relationships. These patients fear abandonment and will often engage in self-harming behavior like cutting and suicide attempts. The main defense mechanism these patients employ is splitting, in which patients divide the world into dichotomous categories where people are either all good or all bad. This personality disorder is associated with mood disorders and substance use. The treatment of choice for these patients is long-term dialectical behavioral therapy and mood stabilizers.

Leichsenring et al. review the evidence regarding the treatment of patients with borderline personality disorder. They discuss no specific form of psychotherapy is superior to others. They recommend starting any form of psychotherapy for these patients to improve outcomes.

Incorrect Answers:
Answer A: Antisocial personality disorder presents with aggressive, criminal behavior. These individuals do not conform to social norms or rules and violate the rights of others. Patients often are not amenable to behavioral modification and therefore incarceration may be necessary in order to protect the rights of others.

Answer B: Avoidant personality disorder presents with excessive shyness and hypersensitivity to rejection. These patients fear social interaction though they strongly desire relationships. Cognitive behavioral therapy can be used in order to encourage these patients to be more open to seeking out relationships.

Answer D: Dependent personality disorder presents with submissive and clingy behavior. They often have a need to be cared for and will be very agreeable and dependent on others. This can be harmful as patients may stay in abusive or degrading relationships due to a fear of being alone. Treatment is with cognitive behavioral therapy.

Answer E: Histrionic personality disorder presents with colorful and exaggerated attention-seeking behavior. These patients will often employ sexuality to draw attention to themselves. Though this patient is displaying her breasts and wearing seductive clothing, her history of self-harm behavior and unstable relationships suggests a diagnosis of borderline personality disorder.

Bullet Summary:
Borderline personality disorder presents with emotional instability, unstable relationships, and self-harming behavior.


Question: A 69-year-old patient presents to the emergency department with shortness of breath and substernal pain. The patient has a medical history of obesity, anxiety, and constipation. He is currently not taking any medications and has not filled his prescriptions for over 1 year. An ECG is obtained and is seen in Figure A. The patient is managed appropriately and is discharged on atorvastatin, metoprolol, aspirin, clopidogrel, and sodium docusate. The patient visits his primary care physician 4 weeks later and claims to be doing better. He has been taking his medications and resting. At this visit, his temperature is 99.5°F (37.5°C), blood pressure is 130/87 mmHg, pulse is 80/min, respirations are 11/min, and oxygen saturation is 96% on room air. The patient states he feels better since the incident. Which of the following is the most appropriate next step in management?

Continue current medications and schedule follow up

Answer: Add lisinopril

Explanation:
This patient is presenting after a myocardial infarction for a follow-up appointment. The most appropriate next step in management is to start an angiotensin-converting enzyme (ACE) inhibitor such as lisinopril.

When a patient experiences a myocardial infarction, there are certain medications that the patient should be started on that lower mortality. These medications include beta-blockers, aspirin, statins, other antiplatelet agents (clopidogrel), and ACE inhibitors. ACE inhibitors can reduce mortality after myocardial infarction by reducing afterload, allowing the damaged myocardium to maintain its ejection fraction. These medications also inhibit ventricular remodeling in this disease. ACE inhibitors most prominently reduce mortality if a patient's ejection fraction is reduced. Of note, ACE inhibitors also reduce mortality in diabetes by decreasing hyperfiltration damage to the glomeruli.

Jering et al. hypothesized that using an angiotensin receptor neprilysin inhibitor would improve mortality in patients who have sustained a myocardial infarction. They discuss how an ACE inhibitor is the standard of care in patients currently. They recommend performing a randomized controlled trial comparing these treatment modalities.

Figure/Illustration A demonstrates an ECG with ST elevation (red circles) in leads II, III, and AVF. These ST elevations are indicative of a STEMI.

Incorrect Answers:
Answer A: Hydrochlorothiazide can be used to manage this patient's blood pressure; however, this drug does not lower mortality like an ACE inhibitor. In the setting of patients with myocardial infarctions, inhibition of detrimental ventricular remodeling is key for lowering mortality.

Answer C: Nifedipine is a calcium channel blocker that can be used to reduce blood pressure; however, it does not reduce mortality in patients who have experienced an MI. Calcium channel blockers tend to have few side effects and can be safely started in most patients.

Answer D: Continuing current medications and scheduling a follow-up appointment misses the opportunity for the patient to be started on a mortality-lowering ACE inhibitor. In patients who are amenable to starting a new medication, an ACE inhibitor should be administered to all patients who have sustained an MI.

Answer E: Switching to carvedilol would be unnecessary and not likely to benefit this patient as much as adding an ACE inhibitor. Metoprolol is the preferred beta blocker in patients who have sustained an MI. In the absence of idiosyncratic side effects, there is no indication to use another beta blocker.

Bullet Summary:
Patients who have experienced a myocardial infarction should be discharged on mortality-lowering drugs such as aspirin, beta-blockers, anti-platelet agents, and ACE inhibitors.


Question: A 4-day-old girl is brought in by her mother for bilateral purulent eye discharge. Pregnancy and delivery were uncomplicated. The newborn had been sleeping regularly and feeding well. Then 1 day ago, the patient developed eyelid edema and eye redness. This morning, the newborn developed a thick yellow-white eye discharge. The mother denies that anyone in the house smokes. The family has a cat at home. The patient’s rectal temperature is 99°F (37.2°C), blood pressure is 80/50 mmHg, pulse is 134/min, and respirations are 34/min with an oxygen saturation of 98% O2 on room air. Figure A shows a photograph of one of the patient's eyes. The patient's physical exam is otherwise unrevealing. Which of the following most appropriately would have prevented this infant's condition?

Answer: Topical erythromycin

Explanation:
This patient is presenting with bilateral purulent eye discharge 4 days post-birth, suggesting the diagnosis of gonococcal conjunctivitis. Standard prophylaxis for this condition is topical erythromycin ointment.

Neonatal gonococcal conjunctivitis is caused by Neisseria gonorrhea and presents in newborns that are 0-5 days old. Symptoms include purulent discharge and eye swelling. Standard prophylaxis for gonococcal conjunctivitis is erythromycin ointment. Silver nitrate drops can also be used as prophylaxis, but this treatment has been abandoned in most practices as it can cause chemical conjunctivitis. Treatment for gonococcal conjunctivitis includes intravenous or intramuscular ceftriaxone. All neonates with gonococcal conjunctivitis should also be treated for chlamydia.

Franco and Hammerschlag prevent the current methods of providing prophylaxis against gonococcal conjunctivitis. They discuss how the development of macrolide resistance may make erythromycin ointment ineffective. They recommend screening and treatment of pregnant women to prevent the development of this disease.

Figure/Illustration A shows a newborn's eye that is exhibiting eyelid swelling, redness, and purulent discharge (red circle). These findings are consistent with gonococcal conjunctivitis.

Incorrect Answers:
Answer A: Artificial tears can be used in the management of chemical conjunctivitis. The most common cause of neonatal chemical conjunctivitis is post-delivery use of silver nitrate drops. Symptoms usually present within the first 24 hours following birth/exposure as mild conjunctival injection and tearing without purulent discharge.

Answer B: Intramuscular ceftriaxone is used as treatment, not prophylaxis, of neonatal gonococcal conjunctivitis. This disease would present with purulent discharge and eye swelling. The goal of prophylaxis is to prevent the development of this condition.

Answer C: Oral erythromycin is used to treat neonatal chlamydial conjunctivitis. Symptoms of chlamydial conjunctivitis usually present 5-14 days post-birth with mild hyperemia and scant mucoid or watery discharge. Patients who are diagnosed with gonorrhea should also be treated empirically for chlamydia.

Answer D: Topical bacitracin can be used as a treatment for gram-positive neonatal bacterial conjunctivitis. It would not be used as a prophylaxis. These patients would present with rapidly progressive infection associated with surrounding soft tissue cellulitis or abscess formation.

Bullet Summary:
Neonatal gonococcal conjunctivitis is treated with an intramuscular shot of ceftriaxone and standard prophylaxis to prevent this condition is with erythromycin ointment.