Question: A 50-year-old man presents to the emergency department with chest pain. He states that the pain is dull in quality, started 30 minutes ago, has been gradually worsening, and is worse with exertion. He also endorses some shortness of breath. He also believes the pain is worse when leaning back and improved when leaning forward. His wife noticed he fainted after the pain started but regained consciousness shortly after. He has a medical history of diabetes and hypertension for which he is on metformin and losartan. His temperature is 99.2°F (37.3°C), blood pressure is 130/87 mmHg, pulse is 99/min, respirations are 22/min, and oxygen saturation is 100% on room air. Physical exam reveals an overweight man. A normal S1 and S2 are auscultated with clear breath sounds. An ECG is performed as seen in Figure A. Which of the following is the most likely diagnosis?

Answer: Myocardial infarction

Explanation:
This patient is presenting with chest pain and an ECG demonstrating hyperacute T waves (leads V2-V6) which is an early finding concerning for a myocardial infarction.

A myocardial infarction occurs when an atherosclerotic plaque ruptures causing occlusion of a coronary artery. Patients classically present with chest pain, dyspnea, and diaphoresis. Atypical manifestations of an acute myocardial infarction may include abdominal pain, nausea, reflux symptoms, and dizziness. The most important initial step in management is to administer aspirin as it lowers mortality and carries minimal risk. An ECG should then be performed. Classically, an ST-elevation myocardial infarction (STEMI) will demonstrate ST elevations in a vascular distribution. However, the progression to a STEMI is usually stepwise and may present with ST depressions, hyperacute T waves, pseudonormalization of the ST segment (a normal ST segment after a depression as it elevates), ST elevations, and finally tombstoning (a concave down wave that looks like a tombstone). If a STEMI is suspected after an ECG is performed, the patient should be started on a second antiplatelet agent (e.g., ticagrelor), heparin, and sent immediately to the cardiac catheterization laboratory.

Nable et al. review the typical electrophysiologic changes found in STEMI. The authors note that T-wave inversions and ST-segment depression can before, during, or after the STEMI event. The authors recommend obtaining serial ECGs in patients with suspected STEMI.

Figure/Illustration A demonstrates hyperacute T waves (blue arrows) that are only occurring in a vascular distribution (V2-V6).

Incorrect Answers:
Answer A: Hyperkalemia can present with peaked T waves; however, peaked T waves would be demonstrated in all leads. Other findings of hyperkalemia can include QRS widening. Immediate management of hyperkalemia with ECG changes should include calcium administration followed by drugs that shift potassium intracellularly such as insulin, albuterol, or sodium bicarbonate. Further management may include diuresis and/or dialysis.

Answer B: Hypertrophic obstructive cardiomyopathy may demonstrate increased voltages throughout the ECG, in particular, in leads V2-V6 with deep Q waves in the septal leads. It may present with syncope upon exertion in a young patient (and in rare cases, sudden cardiac death). Ultrasound would show hypertrophy and left ventricular outflow tract obstruction. Management involves staying hydrated, avoiding strenuous activities, and beta blockers.

Answer C: Hypokalemia can present initially on ECG with U waves and may progress to cardiac dysrhythmias. Repletion with potassium is the preferred treatment, and the magnesium level should be checked as low magnesium can lead to potassium wasting in the kidneys.

Answer E: Pericarditis presents with chest pain worse by laying back and relieved by leaning forward. ECG may demonstrate diffuse ST elevations with PR depressions, and echocardiography may demonstrate a pericardial effusion. Management involves the administration of ibuprofen or colchicine and steroids in refractory cases. However, these therapies should not be used after myocardial infarction.

Bullet Summary:
Hyperacute T waves are an early finding that is concerning for myocardial infarction.


Question: A 24-year-old man presents to the emergency room after a motor vehicle collision. He was the driver in a head-on collision and was not wearing a seatbelt. The patient is acutely intoxicated and is attempting to attack the nurses. Soon after presentation, he is sedated, paralyzed, and intubated. His medical history is unknown. His temperature is 97.6°F (36.4°C), blood pressure is 74/34 mmHg, pulse is 180/min, respirations are 32/min, and oxygen saturation is 98% on room air. Physical exam is notable for jugular venous distension. An electrocardiogram (ECG) is performed as seen in Figure A. Which of the following is the most appropriate next step in management?

Answer: Pericardiocentesis

Explanation:
This patient is presenting after trauma with hypotension, tachycardia, jugular venous distension, and electrical alternans on ECG, which is concerning for cardiac tamponade. The most important initial step in management is pericardiocentesis.

Cardiac tamponade can occur after trauma, infections, or malignancy. It can occur if there is an accumulation of fluid in the pericardial sac with inadequate time for the pericardial sac to stretch and for the heart to adapt to the compression that causes diastolic dysfunction. Patients will present with hypotension, tachycardia, jugular venous distension, muffled heart sounds, and pulsus paradoxus (blood pressure drop > 10 mmHg with inspiration). The diagnosis can be supported with ultrasonography (in the clinical setting a point of care ultrasound will often be performed first); however, the initial step in management is a pericardiocentesis which will stabilize the patient. Subsequent management requires the placement of a pericardial drain or window, as well as treatment of the underlying cause.

Prabhakar et al. discuss pericardial decompression syndrome, an infrequent complication of pericardiocentesis. The authors find that pericardial decompression syndrome presents with paradoxical hemodynamic instability and/or pulmonary edema following pericardiocentesis, especially in patients with underlying myocardial dysfunction. The authors recommend careful monitoring of patients after pericardiocentesis for the development of this complication.

Figure/Illustration A is an ECG demonstrating electrical alternans. Note the alternating large QRS complexes (blue arrows) and small QRS complexes (green arrows) which are suggestive of the heart swinging in a fluid-filled pericardium.

Incorrect Answers:
Answers 1 & 5: Needle thoracostomy followed by tube thoracostomy is the appropriate management of a tension pneumothorax. A tension pneumothorax would also present with hypotension, tachycardia, and jugular venous distension; however, it would not present with muffled heart sounds and electrical alternans on ECG. On exam, there would be an absence of unilateral breath sounds and the presence of tracheal deviation.

Answer B: Packed red blood cells are appropriate management of a hypotensive and tachycardic trauma patient when it is suspected that their unstable vitals are secondary to hemorrhage. In this patient, there is conclusive evidence (jugular venous distension and electrical alternans) that this patient has cardiac tamponade.

Answer C: Pericardial window is the appropriate long-term treatment of recurrent pericardial effusions as it allows for a permanent conduit for the drainage of fluid. An acutely unstable patient should first be stabilized with a pericardiocentesis before going to the operating room for this procedure.

Bullet Summary:
The most important initial step in the management of cardiac tamponade in a hemodynamically unstable patient is pericardiocentesis.


Question: A 59-year-old man presents to his primary care physician for abdominal pain and foul-smelling diarrhea that has persisted for the past 2 years. The patient has a medical history of alcoholism and has been admitted to the hospital multiple times for withdrawal, abdominal pain, and traumatic injuries from his drinking. The patient states that his last drink was more than 1 year ago. His temperature is 99.3°F (37.4°C), blood pressure is 115/78 mmHg, pulse is 78/min, respirations are 15/min, and oxygen saturation is 99% on room air. Physical exam reveals a non-tender, non-distended abdomen. Laboratory studies are notable for a serum calcium of 7.0 mg/dL. A computed tomography (CT) scan of the abdomen is performed as seen in Figure A. A Sudan Black stain of the patient’s stool is positive. Which of the following is the most appropriate treatment for the underlying cause of this patient’s diarrhea?

Answer: Pantoprazole

Explanation:
This patient with a history of alcoholism is presenting with steatorrhea (foul-smelling diarrhea that stains with Sudan Black, a stain that detects fat in the stool), hypocalcemia, and findings suggestive of chronic pancreatitis on CT scan (inflammatory changes and calcification). His steatorrhea can be improved with the administration of proton pump inhibitors such as pantoprazole.

Chronic pancreatitis is a sequela that occurs after repeated bouts of acute pancreatitis. It can occur secondary to alcoholism or gallstones, and it may present with chronic abdominal pain, hypocalcemia, and signs of malnutrition and weight loss. Malnutrition and weight loss occur secondary to the pancreas’ inability to produce pancreatic enzymes which leads to poor nutrient absorption. Lack of lipase can lead to fat wasting in the stool, steatorrhea, and fat-soluble vitamin deficiency (A, D, E, and K). The management of chronic pancreatitis is the cessation of the underlying cause, pancreatic enzyme replacement, and the administration of proton pump inhibitors. Proton pump inhibitors help with steatorrhea by increasing the pH as low pH inactivates pancreatic enzymes.

Singh et al. review the diagnosis and management of chronic pancreatitis. The authors find that the diagnosis can be secured by typical findings on CT or magnetic resonance imaging (MRI) including pancreatic calcifications, ductal dilatation, and pancreatic atrophy. The authors recommend the use of endoscopic ultrasound in securing the diagnosis in patients with equivocal imaging findings and a high index of suspicion, such as patients with repeated episodes of acute pancreatitis.

Figure/Illustration A is a CT scan of the abdomen demonstrating calcifications and chronic inflammatory injury (red arrows) suggesting a diagnosis of chronic pancreatitis.

Incorrect Answers:
Answer A: Ciprofloxacin or ceftriaxone is the appropriate management of infectious diarrhea from a bacterial organism. This usually presents with fever, as well as bloody or purulent diarrhea. In general, young and healthy patients who are able to hydrate themselves should not be given antibiotics, even for infectious diarrhea. Elderly patients, immunosuppressed patients, or patients with symptoms that do not improve spontaneously should be managed with a stool culture and antibiotics.

Answer B: Loperamide is an anti-diarrheal agent that could be used for irritable bowel syndrome to decrease bowel motility and improve symptoms of diarrhea. Loperamide and other antidiarrheals should never be used for infectious causes of diarrhea as they will delay the fecal shedding of the organism or virus and could prolong symptoms.

Answer C: Oral rehydration is recommended for any patient with diarrhea and signs of volume depletion and is preferred to IV fluids as the integrity of the gut is protected. This patient’s diarrhea is likely caused by his chronic pancreatitis; thus, oral rehydration may be indicated but does not address the underlying cause of this patient’s diarrhea.

Answer E: Rifaximin is an antibiotic that targets gut flora and can decrease enteric flora and treat conditions such as small bowel bacterial overgrowth. Small bowel bacterial overgrowth presents in patients with conditions such as diabetic gastroparesis or scleroderma secondary to decreased bowel motility causing bacterial overgrowth and profuse diarrhea. Treating the underlying cause in addition to rifaximin will eliminate the excess bacteria.

Bullet Summary:
Proton pump inhibitors should be given in patients with persistent diarrhea in the setting of chronic pancreatitis to prevent the inactivation of pancreatic enzymes.


Question:
A 43-year-old man presents to the emergency department with bright red blood in his stool this morning. He noticed this yesterday as well, but it was much scanter. The patient is otherwise healthy. He was celebrating his birthday last night and admits having "too much to drink" and vomited profusely overnight. He currently feels well and is not nauseous. He has no other significant medical history and does not take any medications. His temperature is 99.2°F (37.3°C), blood pressure is 110/75 mmHg, pulse is 82/min, respirations are 16/min, and oxygen saturation is 100% on room air. Physical exam reveals a nontender abdomen with normal bowel sounds. Rectal exam reveals grossly bloody stool. Laboratory studies are ordered as shown below.

Hemoglobin: 12 g/dL
Hematocrit: 36%
Leukocyte count: 5,500/mm^3 with normal differential
Platelet count: 179,000/mm^3

Which of the following is the most likely cause of this patient's symptoms?

Answer: Vascular malformation

Explanation:
This patient is presenting with bright red blood per rectum with a non-tender abdomen. Of the answer choices given, angiodysplasia is the most likely to cause such profuse and sudden bleeding.

Angiodysplasia is a vascular malformation found in the gastrointestinal (GI) tract, most commonly in the colon. The exposed vessels can bleed, leading to bright red blood per rectum. The diagnosis can be confirmed with colonoscopy. Ablation can be performed to stop the bleeding. Any patient who is unstable or anemic with a hemoglobin < 7.0 g/dL requires a transfusion with blood products. Angiodysplasia is a common cause of bright red blood per rectum but is not more common than diverticulosis.

Garcia-Compeon et al. review the presentation and treatment of gastrointestinal angiodysplasia. The authors note that angiodysplasias are the cause of many "occult" GI bleeds not visualized on upper endoscopy or colonoscopy. The authors recommend the use of capsule endoscopy in occult GI bleeds to identify angiodysplasias as a potential source.

Incorrect Answers:
Answer A: Erosion into a gastric vessel is the pathophysiology of a bleeding gastric vessel secondary to peptic ulcer disease. This usually presents with melena (black tarry stools) rather than bright red blood per rectum. Only in cases of extremely brisk upper GI bleeding would patients present with bright red blood per rectum. Treatment involves treating Helicobacter pylori infection if present, proton pump inhibitors, and sucralfate. Endoscopy is needed to confirm and treat the bleeding vessel.

Answer B: Inflammation and infection of colonic outpouching is the pathophysiology of diverticulitis which presents with a history of constipation with a fever and left lower quadrant abdominal pain. Management involves a computed tomography (CT) scan of the abdomen/pelvis and administration of antibiotics (such as ciprofloxacin and metronidazole or ceftriaxone and metronidazole). Diverticulosis presents with bright red blood and is possible in this patient, but it does not involve inflammation or infection, which defines diverticulitis.

Answer C: Malignancy or colon cancer can present with bright red blood per rectum, malaise, weight loss, and microcytic anemia. While it is possible in this patient, his age, lack of risk factors for colon cancer, and the sudden onset of his symptoms make this diagnosis less likely.

Answer D: Submucosal esophageal (Mallory-Weiss) tear presents after profuse vomiting (as in this patient) with bloody vomitus. Treatment is supportive and involves antiemetics.

Bullet Summary:
Angiodysplasia is a vascular malformation that presents with bright red blood per rectum.


Question: A 27-year-old man presents to the emergency department after a bar fight. He was punched in the eye and is having pain and blurry vision. The patient is otherwise healthy and does not take any medications. His temperature is 98.1°F (36.7°C), blood pressure is 132/84 mmHg, pulse is 103/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam is notable for conjunctival injection of the patient’s left eye as shown in Figure A. Visual acuity reveals 20/20 vision in his right eye and 20/40 vision in his left. His left pupil is sluggish to constrict when compared to the right. A fluorescein stain is unremarkable and tonometry reveals a pressure of 45 mmHg in the left eye. Which of the following is the most appropriate next step in management?

Answer: Lateral canthotomy

Explanation:
This patient is presenting after blunt trauma to the eye with eye pain, blurry vision, conjunctival injection, a sluggish pupil, and elevated intraocular pressure (> 20 mmHg) suggesting a diagnosis of a retrobulbar hematoma/hemorrhage causing orbital compartment syndrome. The most important initial step in management is a lateral canthotomy to alleviate retrobulbar pressure.

A retrobulbar hematoma (or hemorrhage) occurs after blunt trauma to the eye. Presenting symptoms may include eye pain, photophobia, proptosis (an eye that appears to be anteriorly displaced), decreased visual acuity, and conjunctival injection. It is important to perform a thorough exam including a slit lamp exam and a fluorescein stain to rule out other traumatic injuries such as a globe rupture. Tonometry can be used to assess for increased intraocular pressure. A pressure > 20 mmHg suggests a diagnosis of orbital compartment syndrome, a vision-threatening condition. Immediate management with a lateral canthotomy is indicated in order to relieve pressure on the optic nerve and retina and save the patient’s vision. Further management may require drainage of the hematoma in the operating room.

Burkat et al. review the technique for performing a lateral canthotomy to relieve pressure in retrobulbar hematoma. The authors first excise the skin and orbicularis muscle at the lateral canthal angle in a horizontal direction for approximately 10 mm. The authors then recommend performing an inferior cantholysis by incising the inferior crus (a thick fibrous band connecting the lateral lower eyelid to the orbital rim) near the orbital rim.

Figure A demonstrates proptosis on physical exam which raises concern for a retrobulbar hematoma that is likely increasing orbital compartment pressure.

Incorrect Answers:
Answer A: CT scan of the head and facial bones would be appropriate if there was a concern for facial fracture. It would delay necessary and vision-saving interventions to perform a CT scan in the setting of orbital compartment syndrome. However, cross-sectional imaging may be performed after the pressure is relieved.

Answer B: Cyclopentolate is a cycloplegic that can be used to reduce pain in traumatic iritis. This typically presents after blunt trauma to the eye with erythema, photophobia, blurry vision, and cell/flare in the anterior chamber on slit lamp exam. A sluggish pupil may also be seen; however, increased intraocular pressure would not be seen in this condition.

Answer D: Orbital ultrasound could be used for diagnoses such as a retinal detachment which presents with flashes of light, floaters, and visual field loss like a “curtain coming down over the eye.” An ultrasound would demonstrate the detached retina in the back of the eye. Management involves elevating the head of the bed and surgical reattachment.

Answer E: Topical timolol and pilocarpine in addition to brimonidine, acetazolamide, and possible iridotomy would be the appropriate management of acute closed-angle glaucoma which presents with a rock-hard eye, blurry vision, a mid-dilated and fixed pupil, as well as a headache. This diagnosis can be supported by elevated intraocular pressure on tonometry. This is unlikely for this patient in the context of trauma.

Bullet Summary:
A retroorbital hematoma can cause orbital compartment syndrome which requires immediate treatment with a lateral canthotomy.


Question: A 56-year-old man presents from prison with 1 month of subjective fevers, chills, cough, and night sweats. He noticed a gradual weight loss over the past year despite no changes to his diet or physical activity. He has never smoked cigarettes but does have a history of opiate use prior to incarceration. He does not take any medications. His temperature is 100.8°F (38.2°C), blood pressure is 142/88 mmHg, pulse is 78/min, and respirations are 12/min. Physical exam reveals a thin, ill-appearing man. Pulmonary auscultation reveals faint, inspiratory crackles in the right upper lobe. His chest radiograph is shown in Figure A. Which of the following is the most appropriate next step in management?

Rifampin, isoniazid, pyrazinamide, and ethambutol (RIPE) therapy

Answer: Rifampin, isoniazid, pyrazinamide, and ethambutol (RIPE) therapy

Explanation:
This patient likely has active tuberculosis (TB), as evidenced by his symptoms (fever, night sweats, cough, and weight loss), inmate status, and apical cavitary lesion on chest radiograph. He should be treated with RIPE therapy.

An active TB infection should be suspected in patients with a febrile illness, cough, night sweats, and weight loss along with epidemiological risk factors for TB infection. Risk factors include residence in or previous visits to endemic regions, work in hospitals or nursing homes, imprisonment, and immunosuppression. Treatment typically requires 2 phases: an intensive phase involving 2 months of rifampin, isoniazid, pyrazinamide, and ethambutol (RIPE) therapy and a continuation phase involving 4 additional months of just isoniazid and rifampin. Vitamin B6 (pyridoxine) should be taken with isoniazid to prevent peripheral neuropathy. Rifampin, isoniazid, and pyrazinamide use should be monitored for hepatotoxicity. Ethambutol can cause optic neuropathy.

Conradie et al. discuss the use of a bedaquiline-pretomanid-linezolid (BPal) regimen in the treatment of extensively drug-resistant tuberculosis. The authors find that most patients treated with BPal have a favorable outcome (no treatment failure or disease relapse) after 6 months. The authors recommend the use of this regimen in highly drug resistant TB.

Figure/Illustration A demonstrates a right upper lobe cavitating lesion (arrow) that resulted in extensive necrosis and fibrosis. These lesions are usually localized to the upper regions of the lung due to favorable oxygen concentrations in the apex.

Incorrect Answers:
Answer A: Ampicillin-sulbactam can be used as empiric treatment for a lung abscess to cover anaerobic pathogens and facultative anaerobic streptococci. A lung abscess is associated with aspiration risk factors (such as alcohol use) or poor dentition.

Answer B: Biopsy may be indicated for a solitary cavitary nodule that is suggestive of malignancy. In this case, the patient's inmate status, along with his fever, night sweats, and cough are more suggestive of an infectious rather than malignant etiology.

Answer C: Itraconazole can be used to treat chronic pulmonary aspergillosis. These patients typically have prior or current lung disease such as chronic obstructive pulmonary disease or tuberculosis. The classic air crescent sign may be seen on imaging in a patient with an aspergilloma, a form of pulmonary aspergillosis in which a fungal ball develops within an existing cavitary lesion.

Answer D: Vancomycin can be used to treat a lung abscess due to methicillin-resistant Staphylococcus aureus. S. aureus pneumonia classically presents as a secondary infection that follows an influenza infection.

Bullet Summary:
Active tuberculosis infection should be treated with rifampin, isoniazid, pyrazinamide, and ethambutol (RIPE) therapy.


Question: A 68-year-old man presents for evaluation by a neurologist for an involuntary hand tremor that started approximately 3 months ago. The shaking improves when he reaches for objects but returns when he is not using his hand. His temperature is 98.6°F (37.0°C), blood pressure is 115/70 mmHg, pulse is 70/min, and respirations are 12/min. His left hand exhibits a 4-6 Hz tremor when resting on his lap. The tremor extinguishes with voluntary movement. In addition, his left upper extremity has increased tone with passive range of motion. Which of the following is the most likely diagnosis?

Answer: Parkinson disease

Explanation:
This patient who presents with a low amplitude, 4-6 Hz resting tremor that resolves with voluntary movement and associated rigidity most likely has Parkinson disease.

Parkinson disease is caused by degeneration of dopaminergic neurons in the substantia nigra pars compacta of the basal ganglia. This neurodegenerative process leads to movement abnormalities such as bradykinesia, “cogwheel” muscle rigidity (intermittently increased muscle tone with passive range of motion), shuffling gait, postural instability, and a resting tremor sometimes referred to as “pill-rolling” in quality. Parkinson disease usually presents with unilateral symptoms and subsequently progresses to bilateral involvement. First-line treatment involves dopaminergic drugs such as carbidopa-levodopa. Antimuscarinic agents can also be used for symptom control.

Zhong et al. review the role of the cerebellum in tremor in Parkinson disease. The authors find that the cerebellum may modulate tremor amplitude via cerebello-thalamo-cortical circuits. The authors recommend further study of the cerebellum as an alternative therapeutic target in Parkinson patients with dopamine-resistant tremors.

Incorrect Answers:
Answer A: Cerebellar stroke can manifest as an intention tremor, which presents as an oscillatory tremor that increases in amplitude at the endpoint of visually goal-directed movement. Intention tremors are best exhibited in the finger-nose-finger test in which the patient repeatedly touches their nose and then extends their arm to touch the examiner's finger. Patients would also have more severe symptoms including ataxia, nausea, vomiting, and nystagmus.

Answer B: Essential tremor is a condition that is often familial and presents as a high frequency (4-9 Hz) tremor that occurs with sustained posture and is worsened with movement. Treatment includes propranolol and primidone.

Answer C: Huntington disease is an autosomal dominant trinucleotide repeat disorder that leads to neurodegeneration of the caudate and putamen. Chorea is a hallmark movement abnormality associated with Huntington disease and presents with spontaneous, jerking, purposeless involuntary movements.

Answer D: Lacunar stroke can result in ischemia to the subthalamic nucleus and produce hemiballismus. This presents as spontaneous unilateral explosive movements of an upper extremity and occasionally the ipsilateral lower extremity. Other motor deficits are also expected when there is a lacunar infarct.

Bullet Summary:
Resting tremor is a hallmark of Parkinson disease and presents with low amplitude, 4-6 Hz oscillatory rhythmic movements that temporarily extinguish with voluntary movement.


Question: A 38-year-old man presents to the emergency department with nasal congestion, blurry vision, and diplopia. His nasal congestion started about 1 week ago and he noticed the blurry vision this morning when he struggled to read the words on his television screen. His medical history is significant for IV drug use, HIV (CD4: 47/mm^3), hypertension, hyperlipidemia, diabetes mellitus, and seasonal allergies. His home medications include hydrochlorothiazide, atorvastatin, metformin, cetirizine, darunavir, tenofovir, and emtricitabine. He denies recent IV drug use. His temperature is 100.8°F (38.2°C), blood pressure is 127/85 mmHg, pulse is 78/min, and respirations are 12/min. He has injected conjunctiva and rhinorrhea. His cranial nerves are intact, and his motor and sensory neurologic exam is normal. A MRI of the brain is performed and can be seen in Figure A. Which of the following is the most appropriate next step in management?

Empiric treatment with pyrimethamine-sulfadiazine

Answer: Empiric treatment with pyrimethamine-sulfadiazine

Explanation:
This patient with a past medical history of immunosuppression due to HIV (CD4 < 100/mm^3), new focal neurologic findings, and ring-enhancing lesions on head MRI should be treated empirically with pyrimethamine-sulfadiazine for 10-14 days.

The differential diagnosis for ring-enhancing lesions in patients with HIV is determined by the degree of immunosuppression. For patients with CD4 counts > 200/mm^3, the most likely diagnoses include primary brain tumors and metastases. In patients with CD4 counts < 200/mm^3, the differential includes toxoplasma encephalitis, primary CNS lymphoma, progressive multifocal leukoencephalopathy (PML), and other infections. Patients with CD4 counts < 100/mm^3 should have empiric treatment for toxoplasma encephalitis with pyrimethamine-sulfadiazine with follow-up head imaging after 10-14 days. If the patient fails to improve clinically or the size of the lesion does not change, the next step would be a biopsy of the lesion.

Robert-Gangneux and Darde present a review of toxoplasmosis diagnosis and treatment. They discuss how the incidence of these infections has increased dramatically since the advent of organ transplantation and HIV. They recommend increasing vigilance and prophylaxis for this disease.

Figure/Illustration A is an MRI of the brain that demonstrates a ring-enhancing lesion (red circle) in the right occipital lobe. This lesion is likely causing the patient's visual complaints and is consistent with toxoplasmosis.

Incorrect Answers:
Answer A: Brain biopsy should be performed if the patient has no response clinically or on follow-up head imaging to empiric treatment with pyrimethamine-sulfadiazine for 10-14 days. Biopsy in these cases may reveal a CNS lymphoma or other neoplastic process.

Answer C: Empiric treatment with dexamethasone is indicated for patients with substantial mass effect on imaging and severely depressed mental status, neither of which is present in this patient.

Answer D: Lumbar puncture is contraindicated in patients with focal neurologic findings due to the risk of transtentorial herniation. Lumbar puncture would be indicated in the diagnosis of meningitis which presents with fever, headache, photophobies, and meningeal signs.

Answer E: There is no role for serology for anti-John Cunningham (JC) virus antibodies in the workup of ring-enhancing lesions. If it were safe to perform a lumbar puncture (if the patient had no focal findings and no evidence of mass effect on head imaging), it would be reasonable to perform PCR of the CSF for JC virus.

Bullet Summary:
For patients with a past medical history of HIV with CD4 <100 cells/µL, focal neurologic findings, and ring-enhancing lesions on head imaging, the next step in management is empiric treatment for toxoplasma encephalitis with pyrimethamine-sulfadiazine for 10-14 days.


Question:
A 24-year-old woman with no significant medical history presents to the emergency department for progressive shortness of breath. She endorses decreased exercise tolerance as well as intermittent palpitations. She returned from a recent missionary trip to South America 12 months prior where she endorsed eating a local delicacy as well as a period of fevers and eyelid swelling during her stay. Her temperature is 99.1°F (37.3°C), pulse is 95/min, blood pressure is 130/85 mmHg, respirations are 15/min, and oxygen saturation is 97% on room air. Physical exam is notable for a laterally displaced point of maximal impulse as well as a 2/6 diastolic murmur radiating to the axilla. A blood smear is shown in Figure A. Her laboratory results are:

Leukocyte count and differential:
Leukocyte count: 10,000/mm^3
Neutrophils: 57%
Lymphocytes: 30%
Monocytes: 3%
Eosinophils: 9%
Basophils: 1%
Hemoglobin: 13.1 g/dL
Platelet count: 420,000/mm^3

Which of the following is the most appropriate treatment?

Answer: Benznidazole

Explanation:
This patient presents with symptoms of heart failure, eosinophilia, trypanosomes on peripheral smear, and a history of recent travel to South America consistent with the diagnosis of Chagas disease. Treatment options for Chagas disease include benznidazole and nifurtimox.

Chagas disease is caused by the parasite Trypanosoma cruzi and is most commonly transmitted by the reduvvid (kissing) bug. The disease is endemic to South America and presents in an acute and chronic phase. The acute phase is characterized by fever, headaches, myalgias, and unilateral eyelid swelling (Romaña’ sign) where the infectious agent has been rubbed into the eye. The chronic phase of the disease is characterized by dilated apical cardiomyopathy leading to conduction abnormalities and valvular dysfunction, megacolon, and megaesophagus. Laboratory testing reveals a peripheral eosinophilia and a peripheral blood smear may reveal the infectious trypanosomes. Treatment is with benznidazole and/or nifurtimox.

Perez-Molina and Molina present the data surrounding the diagnosis and treatment of Chagas disease. They discuss how many cases progress to a chronic state characterized by cardiomyopathy, arrhythmias, and organomegaly. They recommend prompt treatment of the disease to avoid end organ damage.

Figure/Illustration A shows a peripheral blood smear with the trypomastigote form of Trypanosoma cruzi (red circle). Note the anterior location of the dense basophilic nucleus.

Incorrect Answers:
Answer A: Amphotericin B is a potent antifungal that has application in the treatment of multiple fungal infections. It is used as a first-line agent for mucormycosis and cryptococcal meningitis (in addition to flucytosine). Amphotericin B with sodium stibogluconate is used to treat visceral leishmaniasis, a protozoal infection most commonly caused by Leishmania donovani. Side effects can include nausea, vomiting, rigors, fever, hypertension or hypotension, renal dysfunction, and hypoxia.

Answer C: Erythromycin is a macrolide antibiotic that is used in the treatment of bacterial infections. It has a pro-motility effect and can also be used as a gastric pro-motility agent. Potential side effects include gastrointestinal upset, prolonged QT interval, inhibition of the P450 system, and pyloric stenosis in infants.

Answer D: Ganciclovir is a synthetic nucleoside analogue that is mainly used in the treatment of cytomegalovirus (CMV) infections. The most common side effects are bone marrow suppression (granulocytopenia, thrombocytopenia, and anemia) and gastrointestinal upset.

Answer E: Praziquantel is an anti-helminthic used in the treatment of tapeworms and flukes including Echinococcus, Taenia solium (cysticerosis), Schistosoma sp., Clonorchis sinensis (liver fluke), and Paragonimus westermani (lung fluke). Side effects of praziquantel develop due to release of contents from dead parasites and can include gastrointestinal upset, elevated liver enzymes, and dizziness.

Bullet Summary:
Treatment of Chagas disease is with benznidazole or nifurtimox.


Question: A 3-year-old girl is brought to the office for a routine well-child appointment. She was delivered preterm at 35 weeks, and her medical history is significant for several ear infections over the last year. Her older brother has been diagnosed with attention-deficit hyperactivity disorder (ADHD), but the rest of her family history is otherwise unremarkable. The patient has become more withdrawn lately and has sometimes been ignoring her parents when asked to perform tasks at home. This seems to have worsened over the last 8 weeks. Otherwise, the patient is energetic and started preschool 3 months ago. Her temperature is 98.6°F (37°C), blood pressure is 98/62 mmHg, pulse is 97/min, and respirations are 26/min. The patient successfully draws a square and can stand on 1 foot. Her language skills are unchanged from her appointment 6 months ago. Her neurological examination is normal, and she is at the 50th percentile for height and weight. She seems distracted during the interview and responds only intermittently to the physician’s directions. Which of the following is the most appropriate next step in management?

Answer: Audiometry testing

Explanation:
This patient who presents with trouble following directions, inconsistent response to the physician's questions, and lack of progression in her language skills may have an acquired hearing impairment. The patient should undergo audiometry testing.

Hearing impairment in children can be genetic or acquired. In a patient with a history of recurrent ear infections, conductive hearing loss is the most common underlying cause of hearing impairment. Hearing impairment can often present similarly to behavioral or persistent developmental disorders. In a child with poor language skills, social skills, and self-isolation, hearing loss should be ruled out first before considering other diagnoses. Undetected hearing loss can progress with poor academic performance, personal-social maladjustment, and emotional difficulties as children progress through critical development stages. The treatment for hearing loss is the restoration of hearing through hearing aids, cochlear implants, and other supportive measures.

Dammeyer et al. studied the impact of childhood hearing loss on family life. They found that children with additional disabilities were more likely to be ignored by parents. They recommend understanding family dynamics in order to better support patients and families.

Incorrect Answers
Answer B: Autism spectrum screening questionnaire is useful in the diagnosis of autism spectrum disorder in children presenting with social isolation and poor communication skills. Autism spectrum disorder often presents with repetitive behaviors and fixed interests, which are absent in this child. Hearing loss should be ruled out first before pursuing this diagnosis. Treatment of autism spectrum disorders is early intervention and counseling.

Answer C: Parent and teacher ADHD rating scales should be obtained to aid in the diagnosis of attention-deficit hyperactivity disorder (ADHD). While children with ADHD often appear inattentive and impulsive in multiple domains, poor language development, and social isolation are not features of ADHD. This patient should first undergo an audiometry test. ADHD can be treated with stimulants such as methylphenidate.

Answer D: Referral for genetic testing is an incorrect first step in the management of this patient. While delayed language can be seen with several genetic conditions, there are usually signs of other global motor, cognitive, and social delays. Additional genetic testing can be pursued if the patient’s audiometry testing results are normal.

Answer E: Referral for speech and language assessment is an incorrect first step. A formal assessment should be obtained in the diagnosis of communication and language disorders. However, this should only be done after ruling out hearing loss. Therefore audiometric testing should be performed first.

Bullet Summary:
Children with a history of recurrent ear infections presenting with signs of social or language development delays should be evaluated for hearing impairment with an audiometry test.


Question: A 32-year-old G1P0 woman at 12 weeks gestation presents to her obstetrician for a follow-up appointment. She first presented 4 weeks ago with bilateral hand tremors. At that time, she was found to have a thyroid-stimulating hormone (TSH) concentration <0.01 mU/L and an elevated free T4. She was started on propranolol and propylthiouracil. The dosage of both medications has been titrated to the maximum dose. She reports mild improvement in her symptoms but continues to experience sweating and palpitations. She has a past medical history of polycystic ovary syndrome. Her family history is notable for hypothyroidism in her mother. She does not smoke cigarettes, stopped drinking alcohol prior to pregnancy, and does not use drugs. Her temperature is 97.6°F (36.4°C), blood pressure is 113/70 mmHg, pulse is 126/min, and respirations are 18/min. On physical exam, she appears anxious, mildly diaphoretic and has a non-tender prominence on her neck which is shown in Figure A. Which of the following is the most appropriate next step in management?

Answer: Thyroidectomy in the 2nd trimester

Explanation:
This patient who initially presented with tremors, a suppressed TSH, and elevated T4 has Graves disease which was appropriately treated with propranolol and propylthiouracil. However, she has persistent symptoms (diaphoresis, palpitations, tachycardia, nontender goiter) despite maximum doses of these medications, which should then be treated with surgical thyroidectomy which can be performed safely in the 2nd trimester of pregnancy.

Graves disease is caused by TSH receptor antibodies that activate the TSH receptor to synthesize thyroid hormone, leading to hyperthyroidism with suppressed TSH levels. The initial treatment for Graves disease is symptom control with a beta-blocker (e.g., propranolol) and inhibition of thyroid hormone synthesis with a thionamide (e.g., propylthiouracil or methimazole). In the 1st trimester of pregnancy, propylthiouracil is preferred to methimazole. In the 2nd and 3rd trimesters, methimazole is the preferred thionamide. The treatment of choice in pregnancy for Graves disease that is refractory to propranolol and a thionamide is thyroidectomy, which can safely be performed in the 2nd trimester. This is reserved only for more severe cases refractory to medical treatment. In nonpregnant patients, radioiodine ablation is the preferred treatment for refractory Graves disease but is contraindicated during pregnancy due to the risk of ablating the fetal thyroid.

Davies et al. reviewed the pathogenesis, diagnosis, and treatment of Graves disease. They found that Graves disease is caused by autoantibodies to the TSH receptor, resulting in overactive thyroid hormone secretion. They recommend that Graves's disease be treated with antithyroid drugs, radioiodine ablation, or surgery depending on clinical characteristics.

Figure A demonstrates goiter, a common finding in Graves disease that reflects thyroid growth in response to activation by TSH receptor antibodies.

Incorrect Answers:
Answer A: Continuing routine prenatal care does not address the symptoms of the patient's hyperthyroidism. Poorly-controlled hyperthyroidism can lead to spontaneous abortion, premature labor, low birth weight, heart failure, and preeclampsia in pregnant individuals. Therefore, Graves disease should be treated in pregnant individuals.

Answer B: Methimazole is a thionamide that is an alternative to propylthiouracil in nonpregnant individuals. It is more potent than propylthiouracil. Methimazole is contraindicated during the 1st trimester of pregnancy due to its teratogenic effects on the fetus during organogenesis.

Answer C: Oral iodinated contrast agents inhibit the peripheral conversion of T4 to T3 and may be used in thyroid storm in nonpregnant patients outside of the United States. Patients with thyroid storm present with tachycardia, arrhythmias, heart failure, and hyperpyrexia.

Answer D: Radioiodine ablation is the preferred definitive treatment for Graves disease in nonpregnant individuals. It is contraindicated in pregnancy as fetal thyroid tissue has developed by 10-12 weeks of gestation and may be ablated alongside the maternal tissue.

Bullet Summary:
Initial treatment of Graves disease in pregnancy is propranolol and propylthiouracil, whereas severe symptoms that are refractory to medical management should be treated with thyroidectomy.


Question: A 72-year-old man presents to the clinic for his annual exam. For the past few months, he has pain in his chest with physical activity. The pain goes away after he takes a break. He reports no chest pain while he is resting, and the pain is not worsening. His past medical history is notable for hypertension, type 2 diabetes mellitus, and hyperlipidemia. His medications include amlodipine, atorvastatin, and metformin. His temperature is 36.5°C (97.7°F), blood pressure is 132/80 mmHg, pulse is 74/min, respirations are 14/min, and oxygen saturation is 98% on room air. He has a regular rate and rhythm, normal S1 and S2, and no murmurs, rubs, or gallops. His anterior, lateral, and posterior chest are non-tender to palpation. His electrocardiogram is shown in Figure A. Troponin I level is < 0.017 ng/mL. Which of the following is the most likely diagnosis?

Answer: Stable angina

Explanation:
This patient who presents with exertional chest pain that is relieved with rest without increasing frequency or intensity of chest pain, a normal electrocardiogram (ECG), and normal troponin level most likely has stable angina.

Angina pectoris is chest pain secondary to myocardial ischemia and is most commonly caused by atherosclerosis, though it can be caused by any etiology leading to narrowing of the coronary arteries. The pain tends to be substernal, dull, squeezing, or pressure-like and can also radiate to the neck or arm. It may also be associated with shortness of breath, dizziness, lightheadedness, nausea/vomiting, or diaphoresis. In stable angina, the chest pain is precipitated by exertion or stress and is consistently relieved with rest or nitroglycerin. ECG tends to be normal, and troponin I levels are not elevated. Treatment of stable angina includes beta blockers and nitrates (for episodes of pain), as well as therapy to prevent disease progression disease progression which may include antiplatelet therapy (aspirin), lipid-lowering medications, and glycemic control. Lifestyle measures are also the mainstay of therapy and may include smoking cessation, exercise, and dietary modification.

Joshi and de Lemos review stable angina. They note the optimal management of this condition. They recommend lifestyle interventions, lipid-lowering therapy, and antiplatelets to reduce morbidity and mortality.

Figure A shows an electrocardiogram with regular rate and rhythm. Every P wave is followed by a narrow QRS complex, which is consistent with normal sinus rhythm.

Incorrect Answers:
Answer A: Costochondritis presents with pain of the chest wall that can be sharp, aching, or pressure-like and typically worsens with cough or deep breathing. It is typically caused by injury to the chest, physical strain, or can be associated with inflammatory conditions such as arthritis. On exam, the pain can be reproduced with palpation of the chest wall, in particular, the costochondral junction. This patient's chest pain is associated with exertion and relieved with rest, and his pain is not reproduced upon palpation of the chest wall. Thus, he is unlikely to have costochondritis.

Answer B: Non-ST elevation myocardial infarction presents similarly to unstable angina with substernal chest pain that is new-onset, accelerating, or occurring at rest, without ST elevations on ECG. However, ST depressions or T wave inversions may be present on ECG, and troponin I and creatine kinase-MB isoenzyme (CK-MB) would be elevated, indicating myocardial injury.

Answer C: ST-elevation myocardial infarction presents with acute onset substernal chest pain that can radiate to the neck, arm, shoulders, or jaw and is sometimes associated with diaphoresis, nausea/vomiting, shortness of breath, lightheadedness, or anxiety. ECG shows ST elevations in a vascular distribution, and troponin I and CK-MB levels are elevated. This patient's ECG does not show ST elevations, and his symptoms are more consistent with stable angina.

Answer E: Unstable angina is characterized by substernal chest pain occurring at rest or occurring with more severity, longer duration, or increasing frequency. ECG may be normal or show ST depression or T wave inversion, and the troponin level is not elevated. It is caused by incomplete coronary artery occlusion by a thrombus or atherosclerosis, commonly due to a ruptured plaque with subsequent clot formation. This patient's chest pain is exertional, does not occur at rest, and is consistently relieved with rest, and thus would be consistent with stable angina.

Bullet Summary:
Stable angina is characterized by exertional chest pain that is not changing in quality or quantity and is relieved with rest.


Question: A 14-year-old boy is brought to the pediatrician for behavioral issues. At school, he interrupts class by making barking noises. His mother notes that he has been making throat-clearing noises daily for the past 2 years. He has no medical problems and takes no medications. He gets along with his 2 brothers, plays turn-taking games with his friends, and completes his chores. His temperature is 98.4°F (36.9°C), blood pressure is 118/72 mmHg, pulse is 72/min, and respirations are 16/min. On exam, he grimaces several times and blinks his eyes rapidly. He does not appear to be reacting to internal stimuli. His mood and affect are normal. Which of the following is the most appropriate treatment for this patient?

Answer: Haloperidol

Explanation:
This patient presents with multiple motor tics (grimacing, eye blinking) and phonic tics (barking, throat-clearing) on a daily basis for more than 1 year, which are consistent with Tourette syndrome. Tourette syndrome can be medically treated with antipsychotic agents such as haloperidol.

Tourette syndrome presents with multiple motor tics (e.g., grimacing, sniffing) and 1 or more phonic tics (e.g., throat-clearing, barking) that occur for at least 1 year. Tics must begin before the age of 18 years, and their location, frequency, type, complexity, or severity must change over time. Attention-deficit hyperactivity disorder (ADHD) and obsessive compulsive disorder (OCD) are often co-morbid conditions. Common first-line treatments for Tourette syndrome-related tics include habit reversal training and alpha-2 agonists such as guanfacine or clonidine. However, the only pharmacologic treatments approved for Tourette syndrome in the United States are the antipsychotics haloperidol, pimozide, and aripiprazole. Risperidone is also used due to its favorable side effect profile.

Seideman and Seideman review the current treatments for Tourette syndrome. They note it is a hyperkinetic movement disorder that often occurs in children and presents with motor and phonic tics. They recommend treating with both non-pharmacological and pharmacological treatments for optimal care.

Incorrect Answers:
Answer A: Clozapine is an atypical antipsychotic that blocks dopamine D2 receptors but is not approved for treatment of Tourette syndrome. It is typically avoided due to the risk for agranulocytosis and is mainly used for treatment-resistant schizophrenia as a last-line agent. Weight gain is another significant side-effect.

Answer B: Dextroamphetamine is a stimulant commonly used for the treatment of ADHD. ADHD can be comorbid with Tourette syndrome but presents with hyperactivity (e.g., fidgeting, difficulty taking turns, blurting out answers) and/or inattentive symptoms (e.g., daydreaming, difficulty completing tasks) in at least 2 settings. While this patient’s phonic tics are disruptive, he has no difficulty waiting his turn and completing his chores, making Tourette syndrome more likely.

Answer C: Fluoxetine is a selective serotonin reuptake inhibitor (SSRI) that may be used for the treatment of OCD. OCD is often co-morbid with Tourette syndrome but compulsions are present, which manifest as repetitive counting, hoarding, tapping, or error checking. This patient’s behavior is better attributed to his tics rather than compulsions.

Answer E: Methylphenidate is a stimulant used for the treatment of ADHD. ADHD would present with hyperactivity and/or inattentive symptoms. The patient's vocal interruptions are better attributed to his phonic tics.

Bullet Summary:
Tourette syndrome is treated with habit reversal training, alpha-2 agonists (e.g., guanfacine, clonidine), and/or antipsychotics (e.g., haloperidol, risperidone).


Question: A 7-year-old adopted boy presents to the emergency department after fainting. He just switched from being home-schooled to public school and joined the basketball team. He has fainted several times during basketball practices. He did not sustain any injuries or have any prodromes prior to these episodes. He is usually unconscious for less than a minute. He is otherwise healthy and has met all developmental milestones. He does not currently take any medications. His temperature is 97.6°F (36.4°C), blood pressure is 104/54 mmHg, pulse is 100/min, respirations are 19/min, and oxygen saturation is 98% on room air. Physical exam reveals a well-appearing and playful boy. An ECG is performed as seen in Figure A. An echocardiogram is ordered and pending. Which of the following is the most likely diagnosis?

Answer: Arrhythmogenic right ventricular dysplasia

Explanation:
This adopted pediatric patient is presenting with recurrent syncope and an ECG demonstrating an epsilon wave and T wave inversions, which are concerning for arrhythmogenic right ventricular dysplasia.

An epsilon wave is a small positive deflection at the end of the QRS complex. This is an ominous finding and suggests a diagnosis of arrhythmogenic right ventricular dysplasia (ARVD) though it may also be seen in other infiltrative diseases such as sarcoidosis or after ischemic events. ARVD is an autosomal dominant condition where there is fatty infiltration of the right ventricular wall predisposing the patient (classically younger patients) to sudden cardiac death from lethal ventricular dysrhythmias. The epsilon wave is the most specific finding; however, other findings include T wave inversion in V1-V3 or a left bundle branch appearance with frequent premature ventricular complexes among other possibilities. This is a potentially lethal diagnosis and requires management with antiarrhythmics (such as beta-blockers or amiodarone) and the placement of an implantable cardioverter-defibrillator.

Kayser et al. review AVRD. They note the presentation and management of ARVD and how it may present initially only with syncope. Cardiac arrest is a possible presentation as well. They recommend early detection and treatment with an implantable cardioverter-defibrillator to prevent death in this population.

Figure/Illustration A is an ECG with an epsilon wave (red arrow) and inverted T waves in V1/V2 (blue arrows) concerning for ARVD.

Incorrect Answers:
Answer B: Brugada syndrome is an autosomal dominant mutation in cardiac ion channels that presents with a possible right bundle branch pattern with ST segment elevation in V1-V3 or ST coving in these same leads. It may present with syncope.

Answer C: Hypertrophic obstructive cardiomyopathy presents with syncope, sudden death, or cardiac arrest in a young patient associated with exertion or dehydration. It can cause obstruction of the left ventricular outflow tract. A systolic murmur can be heard on cardiac auscultation and echocardiography can confirm the diagnosis. ECG will demonstrate large voltages in V1-V5.

Answer D: QT prolongation can lead to torsades des pointes which presents with twisting of the QRS complexes around an isoelectric baseline. It may present with syncope, hemodynamic instability, or cardiac arrest. Medications, infection, and congenital conditions may prolong the QT interval.

Answer E: Wolff Parkinson White syndrome presents with a delta wave on ECG or a slurred upstroke of the QRS complex. It may cause syncope and evolve into other dysrhythmias including supraventricular tachycardia and ventricular tachycardia.

Bullet Summary:
Arrhythmogenic right ventricular dysplasia (ARVD) may cause syncope or cardiac arrest, and presents on ECG with an epsilon wave.


Question: A 34-year-old man presents to the emergency room with pain behind his eyes. He had a similar episode about 1 month ago which resolved after a few hours. The pain feels like a stabbing sensation behind his right eye. He denies any symptoms on the left side. The last time he had an episode like this, his eye was tearing. His temperature is 98.2°F (36.8°C), blood pressure is 120/90 mmHg, pulse is 110/min, and respirations are 12/min. Physical exam reveals a 2 mm pupil on the right and a 5 mm pupil on the left. Extraocular movements are intact bilaterally. The remainder of the neurologic exam is unremarkable. Which of the following is the most appropriate prophylactic treatment?

Answer: Verapamil

Explanation:
This patient with a history of retro-orbital pain, unilateral miosis (2 mm pupil on the right), and history of lacrimation during a similar episode is likely experiencing cluster headaches. Verapamil may be used as prophylaxis in the treatment of cluster headaches.

Cluster headaches occur more commonly in men and present with severe, unilateral, retro-orbital pain. Typical episodes last 15 minutes to 3 hours. Attacks may be associated with the circadian rhythm, as patients may notice that they get headaches at night. Because of the extreme pain, cluster headaches are sometimes colloquially referred to as "suicide" headaches. These headaches may present with autonomic symptoms, such as lacrimation and rhinorrhea. Horner syndrome may also occur, defined by a unilateral triad of ptosis, miosis, and anhidrosis. Acute management of cluster headaches includes administration of 100% oxygen. Other options include triptans. The first-line medication for prophylaxis of cluster headaches is verapamil. Studies have shown that lithium, topiramate, and ergotamine may also be effective as prophylaxis for cluster headaches; however, these therapies are less established than verapamil.

Blau and Engel review the use of medications for cluster headaches. They note that most of patients with episodic cluster headaches had complete suppression of attacks with the use of verapamil. It is recommended to give verapamil in this patient population.

Incorrect Answers:
Answer A: Ibuprofen is a non-steroidal anti-inflammatory drug (NSAID) that is used in the treatment of migraine and tension headaches. Migraine headaches present with unilateral, pulsating pain with photophobia and phonophobia, whereas tension headaches present with constant bilateral pain. Ibuprofen should not be used as prophylaxis for any type of headache as it has side effects including kidney dysfunction, ulcers, and even premature aging.

Answer B: Oxygen is first-line treatment for acute cluster headaches; however, it does not have any role in the prophylaxis of cluster headaches.

Answer C: Propranolol is a beta-blocker that is a prophylactic medication for migraine headaches. Migraines are more common in women and typically present as a unilateral headache with photophobia or phonophobia. They may also be associated with an aura, which presents as a visual, auditory, olfactory, or motor disturbance.

Answer D: Sumatriptan is a triptan that is used as an abortive treatment for migraine headaches and cluster headaches. It should not be used as prophylaxis for headaches.

Bullet Summary:
Verapamil may be used as prophylaxis for cluster headaches.


Question: A 69-year-old man passes away after a 3-week hospitalization for liver failure, complicated by a myocardial infarction. A medical student rotating in the intensive care unit asked if she can practice performing intubations during her rotation. The resident suggests performing one on the deceased patient, as the student cannot harm him. Which of the following is the most appropriate course of action for the medical student?

Ask the resident if the patient’s family or the patient has been consented for this procedure

Contact the patient's family to ask for permission to perform the procedure

Intubate the patient with the resident's supervision

Report the resident to hospital administration

Answer: Ask the resident if the patient’s family or the patient has been consented for this procedure

Explanation:
This medical student wants to perform a procedure on a deceased patient for educational purposes. Before proceeding, the student should ensure that permission has been obtained from the patient's family or the patient when he was alive.

Performing procedures on deceased patients is ethically permissible with appropriate consent and consideration of risks and benefits for patients, families, learners, staff, and the field of medicine. Supervising physicians must obtain informed consent from the patient while alive and with capacity or from a newly deceased patient’s healthcare proxy or family. During the consent process, the supervisor should outline the patient's and family's rights, wider educational and societal benefits, potential risks, and ensure that performing the procedure would be consistent with the patient's values and wishes. Additionally, the supervising physician has a responsibility to ensure that a medical examiner has cleared the patient and that the patient is not an organ donor before proceeding. Finally, the procedure should be documented in the patient's chart.

Berger and Cassell review the ethics of practicing procedures on deceased patients. They note that some ethical norms may suggest this practice is not appropriate. They recommend performing procedures when consent is obtained and it is ethically acceptable to do so.

Incorrect Answers:
Answer B: Consulting the hospital ethics committee is not necessary, for with proper permission, trainees may perform procedures on deceased patients for educational purposes. The ethics committee should only be consulted when there is no clear course of action (an example may be no advanced directive with family members disagreeing on what the patient's wishes would have been for a critically ill patient).

Answer C: Contacting the patient's family to ask for permission to perform the procedure is incorrect, as the supervising physician needs to verify and document consent. Medical students cannot consent patients and family members. Moreover, the family should not be contacted if the patient has already approved or refused this when he had capacity.

Answer D: Intubating the patient with the resident's supervision is incorrect because proper permission must be ensured prior to performing educational procedures on deceased patients.

Answer E: Reporting the resident to hospital administration is incorrect because it is ethically permissible to perform an intubation on a deceased patient provided there is proper permission. The resident is not asking the medical student to do anything illegal or against hospital policy. Reporting the resident may be indicated if the resident was performing procedures against the patient's will.

Bullet Summary:
Trainees may perform procedures for educational purposes on deceased patients if permission is obtained from the patient prior to death, the patient's family, or a healthcare proxy.


Question: A 30-year-old woman presents to the emergency department for palpitations. For 2 months, she has experienced intermittent palpitations along with menstrual irregularity and hair loss. At home, the air conditioner is at its coldest setting, but the patient still feels overheated. Her temperature is 99.5°F (37.5°C), blood pressure is 135/90 mmHg, pulse is 120/min, and respirations are 22/min. The patient is diaphoretic with tremulous hands, demonstrates thyromegaly, and protrusion of her eyes is noted. She is given atenolol in the emergency department with improvement of her palpitations and is instructed to follow up with her primary doctor for further management. Which of the following is most likely to be found in this patient after definitive treatment of her condition?

Answer: Exophthalmos

Explanation:
This patient presents with palpitations, tachycardia, tremor, heat intolerance, hair loss, menstrual irregularity, goiter, and exophthalmos concerning for hyperthyroidism due to Graves disease. Radioiodine ablation is the preferred definitive management for Graves disease, which can worsen exophthalmos.

Graves disease is an autoimmune hyperthyroid disorder caused by antibodies to the thyroid stimulating hormone receptor (TSHR), which induce production of T4 and triiodothyronine (T3). Overstimulation of the thyroid gland by TSHR antibodies results in diffuse enlargement of the thyroid gland, termed “goiter.” TSHR is also highly expressed in retro-ocular adipocytes and fibroblasts, where overstimulation by TSHR antibodies (and activated T-cells) leads to the expansion of retro-ocular connective tissue and extra-ocular muscle volume. This causes exophthalmos (bulging eyes) and is referred to as Graves ophthalmopathy or orbitopathy. Beta blockers are used to achieve acute sympathetic control in hyperthyroid Graves patients, and antithyroid medications (propylthiouracil or methimazole) are initiated to achieve a euthyroid state. Radioactive iodine ablation is first-line definitive management, particularly, for individuals with unsuccessful anti-thyroid medication management. Radioiodine ablation has been known to increase TSHR-antibodies, likely secondary to the leakage of thyroid antigens, and thus exophthalmos is often worsened after treatment. For this reason, corticosteroids are often co-administrated as a prophylactic measure.

Davies et al. review Graves disease including the pathophysiology and management. They note that Graves orbitopathy may be worsened by radioiodine ablation. They recommend further studies and advancements in care given this lasting complication.

Incorrect Answers:
Answer B: Hair loss can occur in hyperthyroid and hypothyroid states due to altered hair follicle stem cell function. However, this process is typically reversed, not worsened, after achieving a euthyroid state.

Answer C: Heat intolerance occurs in Graves disease due to hyperthyroid-induced sympathetic overactivity, which resolves after successful treatment.

Answer D: Menstrual irregularity occurs in hyperthyroidism through altered levels of sex hormone binding globulin, gonadotropin-releasing hormone, and prolactin. However, treatment of hyperthyroidism typically restores menstrual regularity. After ablation, patients will be hypothyroid; however, the standard of care is to start the patient on levothyroxine which should prevent this complication.

Answer E: Thyromegaly in Graves disease is caused by diffuse overactivation of the thyroid gland by the TSHR antibodies. Once treated with radioactive iodine (I-131), the thyroid gland gradually shrinks in size. Patients who undergo radioactive iodine ablation will later require life-long thyroxine supplementation due to resulting hypothyroidism.

Bullet Summary:
Definitive therapy for Graves disease is radioiodine ablation, which leads to increased TSHR antibodies and worsened exophthalmos from overactivation of TSHR-rich retro-ocular adipocytes and fibroblasts.


Question:
A 55-year-old man presents to the emergency department after feeling lightheaded then fainting while he was carrying boxes upstairs. The patient works on a farm and does not see a doctor often. He has a history of hypertension but does not take medications routinely. He has not had any chest pain, dyspnea, or weakness during this time frame and currently feels at his baseline. He smokes cigarettes occasionally. His temperature is 98.1°F (36.7°C), blood pressure is 152/93 mmHg, pulse is 86/min, respirations are 15/min, and oxygen saturation is 98% on room air. Physical exam is unremarkable and the patient walks with a stable gait and no focal weakness. An ECG is performed as seen in Figure A. Laboratory studies are ordered as seen below.

Hemoglobin: 12 g/dL
Hematocrit: 36%
Leukocyte count: 6,500/mm^3 with normal differential
Platelet count: 197,000/mm^3

Serum:
Na+: 140 mEq/L
Cl-: 102 mEq/L
K+: 4.3 mEq/L
HCO3-: 24 mEq/L
BUN: 20 mg/dL
Glucose: 139 mg/dL
Creatinine: 1.1 mg/dL
Troponin: < 0.01 ng/mL

Which of the following is the most likely diagnosis?

Answer: Left ventricular hypertrophy

Explanation:
This patient with chronic untreated hypertension is presenting with syncope and an ECG demonstrating large voltages in leads V1-V6 and a left ventricular strain pattern (ST depressions in V5/V6 and aVL), which are concerning for left ventricular hypertrophy.

Left ventricular hypertrophy occurs secondary to chronic hypertension or conditions that increase afterload such as aortic stenosis. This leads to an increase in the mass of the left ventricle. There are many possible criteria on ECG for left ventricular hypertrophy including left axis deviation, large R waves, a large S wave in aVR, or ST segment depression and T wave inversion in the left heart leads (referred to as left ventricular strain). A more simple method of recalling left ventricular hypertrophy is very large voltages in the ECG leads that serve the left ventricle. Left ventricular hypertrophy should be considered in presentations such as syncope. Note that while ECG findings suggest left ventricular hypertrophy, the diagnosis must be supported with echocardiography. Management involves treating the underlying cause (most commonly, this is hypertension).

Artham et al. discuss left ventricular hypertrophy. They note that it is a risk factor for future cardiac events and increased mortality. They recommend early diagnosis and management to improve outcomes.

Figure/Illustration A is an ECG with very large voltages (red arrows) and ST segment depressions/T wave inversions (blue arrows, a more classic left ventricular strain pattern), concerning for left ventricular hypertrophy.

Incorrect Answers:
Answer B: Non-ST elevation myocardial infarction would present with nonspecific ST segment and T wave changes with an elevated troponin. While this patient does demonstrate ST depressions in the lateral leads, the troponin level is normal.

Answer C: ST elevation myocardial infarction would present with ST elevation in a vascular distribution on ECG in the setting of chest pain, diaphoresis, and an elevated troponin level. Note that this patient’s lack of symptoms (pain) and normal troponin in the setting of the ST elevation in leads V1-V3 make this unlikely to be ST elevation myocardial infarction and more likely to be left ventricular hypertrophy.

Answer D: Torsades des pointes occurs in patients with a prolonged QT interval that evolves into twisting of the QRS complexes around an isoelectric baseline. It may cause syncope or cardiac arrest. Note there is no QT prolongation on this patient’s ECG that would predispose him to this condition.

Answer E: Wolff Parkinson White syndrome presents with a delta wave on ECG (a slurred upstroke into the QRS complex) and may undulate with supraventricular or ventricular tachycardia. There is no delta wave in this patient’s ECG supporting this diagnosis. Ablation is the most effective long-term treatment.

Bullet Summary:
Left ventricular hypertrophy can be associated with syncope and presents with large voltages in the leads that serve the left ventricle and a left ventricular strain pattern.


Question: A 28-year-old G1P0 woman presents to initiate prenatal care after a positive home pregnancy test. The first day of her last menstrual period was 7 weeks prior to presentation. The patient has no medical conditions and takes no medications. Her temperature is 98.6°F (37.0°C), blood pressure is 110/70 mmHg, pulse is 64/min, and respirations are 17/min. Physical exam is notable for a nontender abdomen. Pelvic exam reveals a closed cervix with no adnexal or uterine tenderness. A urine pregnancy test is positive, and an intrauterine singleton pregnancy measuring approximately 9 weeks gestational age is visualized on transvaginal ultrasound. The patient asks if she should modify her current exercise regimen due to her pregnancy. She typically swims or uses an exercise bike for 45 minutes, 5 days a week, and plays in an office soccer league for 1 hour on 1 day per week. Which of the following is the most appropriate recommendation regarding exercise for this patient?

Avoid soccer during pregnancy, continue other activities

Reduce to walking only, beginning in the third trimester

Answer: Avoid soccer during pregnancy, continue other activities

Explanation:
This healthy primigravida woman presents to the clinic inquiring about her current exercise regimen involving 285 minutes of moderate to exercise weekly. With the exception of soccer, a contact sport, her exercise regimen is appropriate throughout her pregnancy.

The American College of Obstetricians and Gynecologists (ACOG), recommends that healthy pregnant women engage in moderate-intensity exercise for at least 30 minutes or more for 5-7 days weekly provided there are no contraindications to doing so (certain cardiac or pulmonary conditions, history of cerclage placement, multiple pregnancies, preeclampsia, or severe anemia). Highly active patients may continue their more vigorous pre-pregnancy regimens after consulting with a physician. Exercise in pregnancy can ease gastrointestinal symptoms and may decrease the risk of gestational diabetes, preeclampsia, and cesarean delivery. However, activities that may cause fetal or maternal injury, such as contact sports or activities with a significant fall risk should be avoided. Examples of contact sports include football, basketball, hockey, lacrosse, and wrestling.

Nascimento et al. review exercise in pregnancy. They note that exercise is beneficial in pregnancy and in the postpartum period and recommend engaging in appropriate exercise in this patient population.

Incorrect Answers:
Answer A: Avoiding exercise during pregnancy is not recommended, as at least 150 minutes of moderate exercise weekly is suggested during pregnancy for the health of the mother and the fetus.

Answer C: Continuing the current exercise regimen is not recommended, as soccer is a high-contact sport that could cause injury to the fetus or placenta.

Answer D: Limiting moderate exercise to 30 minutes per day maximum during pregnancy is not recommended, as 30 minutes daily is the minimum recommended time for moderate-exercise. There is no reason for healthy pregnant patients without high-risk pregnancies to significantly limit their exercise.

Answer E: Reducing to walking-only beginning in the third trimester is not necessary, as moderate activities are healthy throughout pregnancy.

Bullet Summary:
Healthy pregnant patients should perform at least 30 minutes of exercise 5-7 days per week and avoid high-contact sports or sports with fall risk.


Question: A previously healthy 15-year-old boy presents to the emergency department in cardiac arrest. He was in class when he suddenly fainted and became unresponsive. His teacher began chest compressions and he has received epinephrine and defibrillation from paramedics while in transport. On arrival, the patient remains pulseless and is pronounced dead. An autopsy is performed and is notable for no clear abnormalities. The patient’s laboratory studies were unremarkable from a visit to the pediatrician 3 weeks ago. A previous ECG is seen in Figure A. Which of the following is the most likely underlying etiology of this patient’s death?

Answer: Short QT syndrome

Explanation:
This healthy pediatric patient is presenting with cardiac arrest and an ECG demonstrating a short QT segment. Short QT syndrome is lethal and can lead to cardiac arrest in young, otherwise healthy patients.

Short QT syndrome is an inherited condition that is caused by ion channel mutations (the most common identified mutation is a mutation in the cardiac myocyte potassium channel). There is no strict criteria for short QT syndrome, but the QT segment is often < 320 ms. Patients are usually young and healthy, and it is very common for the first presentation of this disease to be syncope or sudden cardiac death. ECG features suggestive of this condition include a short QT interval (without a clearly defined value but often < 360 ms) that is fixed (does not change with exercise or rest), peaked T waves, short or even absent ST segments, and episodes of atrial fibrillation or ventricular fibrillation in a patient in whom this would not be expected (such as a young patient). The only effective intervention is the placement of an implantable cardioverter-defibrillator.

Bjerregaard and Gussak discuss short QT syndrome. They note it is a heritable condition of the conduction system of the heart that can lead to lethal dysrhythmias. They discuss the management of this condition and recommend an implantable cardioverter-defibrillator.

Figure/Illustration A is an ECG demonstrating a short QT segment (red arrow). Note the T waves appear peaked which can be seen in this syndrome. This may suggest hyperkalemia, but this patient’s labs were normal at his appointment when the ECG was taken.

Incorrect Answers:
Answer A: Complete heart block is more common in elderly patients with acute coronary syndrome and presents with regular P-P and R-R intervals with complete P-R dissociation. It may cause syncope but is not associated with short QT syndrome. Management involves the placement of a pacemaker.

Answer C: Torsades des pointes is associated with a prolonged QT segment that progresses to the classic twisting of the QRS complexes around an isoelectric baseline. It can lead to cardiac arrest and requires immediate cessation of QT-prolonging medications and administration of magnesium. Note that this patient’s QT segment is short rather than long.

Answer D: Ventricular fibrillation presents with disorganized electrical activity with no discernible rhythm. While this patient may have arrested from ventricular fibrillation, the most likely underlying etiology for his cardiac arrest given his age, ECG, and risk factors is an underlying condition such as short QT syndrome. For this reason, short QT syndrome is a better answer.

Answer E: Ventricular tachycardia could also occur in short QT syndrome and may have caused this patient’s cardiac arrest. It presents with a monomorphic wide complex tachycardia that may cause arrest. Unstable patients require cardioversion while pulseless patients require defibrillation. Note that if this patient arrested from ventricular tachycardia, it was likely secondary to short QT syndrome.

Bullet Summary:
Short QT syndrome is a rare but possible diagnosis in young, healthy patients who present with recurrent syncope or cardiac arrest.


Question:
A 44-year-old nurse presents to the emergency department with confusion. This has happened several times this past month with increasing frequency. Each time her symptoms improved with eating. She is otherwise healthy. She lives with her mother who has diabetes whose medications include metformin, insulin, lisinopril, amlodipine, and glyburide. Her temperature is 98.0°F (36.7°C), blood pressure is 132/81 mmHg, pulse is 85/min, respirations are 16/min, and oxygen saturation is 98% on room air. Physical exam reveals a confused woman. She is moving all her extremities but follows commands poorly. Laboratory studies are ordered as seen below.

Hemoglobin: 14 g/dL
Hematocrit: 41%
Leukocyte count: 7,500/mm^3 with normal differential
Platelet count: 199,000/mm^3

Serum:
Na+: 140 mEq/L
Cl-: 102 mEq/L
K+: 4.0 mEq/L
HCO3-: 23 mEq/L
BUN: 30 mg/dL
Glucose: 29 mg/dL
Creatinine: 1.4 mg/dL
Ca2+: 10.2 mg/dL
Sulfonylurea level: undetectable
C-peptide level: 55 ng/mL (normal < 5 ng/mL)

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

Answer: Beta cell tumor

Explanation:
This patient is presenting with confusion, profound hypoglycemia, an elevated C-peptide level, and a negative sulfonylurea level, which are concerning for an insulinoma. An insulinoma is a beta cell tumor that secretes insulin.

An insulinoma is a beta cell tumor of the pancreas. The beta cells normally secrete insulin in response to increased circulating fuel substrate (such as glucose or fat). In the setting of an insulinoma, insulin is pathologically and continuously secreted. This leads to profound, recurrent episodes of hypoglycemia. When a patient presents with hypoglycemia of unclear etiology; a blood glucose level, C-peptide level, and sulfonylurea level should be ordered. An infectious workup may be indicated as sepsis can also cause hypoglycemia. In an insulinoma, patients will be hypoglycemic, have an elevated C-peptide level (as this is a marker of endogenous insulin release), and a negative sulfonylurea level (important to rule out as a sulfonylurea overdose can also cause hypoglycemia in the setting of an elevated C-peptide level). Further workup will involve imaging of the abdomen such as a CT scan or MRI (more accurate) to delineate this insulin-secreting mass.

Mathur et al. discuss insulinoma. They note that it is a rare endocrine tumor, and note its association with multiple endocrine neoplasia type 1. They recommend workup for an insulinoma should occur in patients with recurrent episodes of hypoglycemia without a clear cause.

Incorrect Answers:
Answer A: Alpha cell tumor describes a glucagonoma, which pathologically secretes glucagon leading to profound hyperglycemia, a classic rash termed necrolytic migratory erythema (presents with painful, erythematous papules and plaques), and gastrointestinal symptoms including anorexia, abdominal pain, and diarrhea.

Answer B: Beta cell destruction describes the pathophysiology of type I diabetes mellitus, which presents in pediatric patients (most commonly) with hyperglycemia, weight loss, polydipsia, and polyuria. Treatment involves the administration of insulin. An initial presentation of type I diabetes may be diabetic ketoacidosis which presents with dehydration, abdominal pain, nausea, vomiting, Kussmaul respirations, and an anion gap acidosis.

Answer D: Insulin overdose would present with hypoglycemia, somnolence, confusion, and tremulousness. Note that exogenous insulin administration would not elevate the C-peptide level, which is a marker of endogenous insulin production.

Answer E: Sulfonylurea overdose would cause hypoglycemia that is often persistent given the long half-life of sulfonylureas. It would also elevate the C-peptide level as these medications increase the endogenous release of insulin. However, the sulfonylurea level was negative in this patient. While iatrogenic use of medications is plausible in this patient who has knowledge of medications (as she is a nurse), her repeat episodes and her workup suggesting against an iatrogenic etiology makes an insulinoma a more likely diagnosis.

Bullet Summary:
Insulinomas are beta cell tumors of the pancreas and lead to severe hypoglycemia and an elevated insulin and C-peptide level.


Question: At a local community hospital staffed only by attending physicians, it is noted that the time to tissue plasminogen activator administration in suspected stroke patients is roughly 10 minutes from presentation. At a teaching hospital with residents, the time to tissue plasminogen activator administration is roughly 2 hours. This has led to many adverse outcomes and increased morbidity at the teaching hospital. Which of the following is the most appropriate next step in further elucidating the problem?

Perform a systems-based approach implementation

Perform a root cause analysis of the process

Empirically scan patients with concerning neurologic symptoms

Automatically consult neurology for patients with concerning neurologic symptoms

Answer: Perform a root cause analysis of the process

Explanation:
This case outlines a delay in treating strokes at a teaching hospital. To determine the underlying cause, a root cause analysis to determine the underlying issue is the most appropriate way to begin to address this issue.

When a problem is found in healthcare, it is important to elucidate the underlying cause. A root cause analysis is the current preferred method of determining the underlying cause of a problem. A root cause analysis outlines all the people, materials, equipment, and processes in place and outlines them. It then locates the problem and attempts to find the breakdown or issue in all these inputs that lead to the problem. Once the problem is identified, then a strategy or intervention can be implemented to fix the underlying problem.

Percarpio et al. review root cause analysis. They note the ubiquity of root cause analysis. They call into question its cost and efficacy despite it being such a widespread practice and recommend a careful assessment of the costs and benefits.

Incorrect Answers:
Answer A: Automatically consulting neurology for patients with concerning neurologic symptoms may be appropriate if the issue was lack of access to timely neurologist assessment in the workup of stroke. While may hospitals have this as a default for patients with stroke-like symptoms, it would be premature to implement this as a solution without a root cause analysis to first determine what the problem is.

Answer B: Empirically scanning patients with concerning neurologic symptoms would be wasteful and not plausible in a healthcare system. There are many concerning neurologic chief complaints including those that originate in the brain, the spine, or the peripheral nerves; thus, merely CT scanning everyone with a neurological chief complaint is an inefficient use of resources.

Answer C: Improving resident education is assuming that the problem is a lack of knowledge based on the residents. Before proposing a solution, it is important to first find the underlying cause and address said cause as the delayed intervention may not be the fault of the residents.

Answer E: A systems-based approach is the best solution when fixing a medical error. However, a root cause analysis is first needed to determine which solution is needed. If an error in the process is noted, a systems-based approach would be the best method to address it.

Bullet Summary:
When an error is noted in patient care, the most appropriate initial step in fixing the issue is conducting a root cause analysis.


Question: A 67-year-old man presents to the emergency department after fainting. He was outside tending to his lawn for several hours in the heat, when he stood up suddenly from pulling weeds and fainted. He denies any preceding symptoms and returned to baseline within 1 minute. The patient is not aware of any medical problems and just started seeing a primary care physician last week. He recently used a friend's prescription for ondansetron for nausea. His temperature is 99.3°F (37.4°C), blood pressure is 142/88 mmHg, pulse is 107/min, respirations are 14/min, and oxygen saturation is 99% on room air. Physical exam reveals intact cranial nerves, normal strength and sensation, and a stable gait. His abdomen is soft and nontender. An ECG is performed as seen in Figure A. Which of the following is the most likely diagnosis based on this patient’s ECG?

Answer: Previous myocardial ischemia

Explanation:
This patient is presenting after syncope, likely secondary to dehydration and orthostatic hypotension given his outdoor gardening in the heat and symptoms when standing up rapidly. The patient’s ECG reveals deep, pathologic Q waves, which in this case are an incidental finding indicative of a previous myocardial infarction or a previous ischemic event.

The Q wave is a negative deflection just prior to the R wave. Q waves are a normal finding when they are small and are seen on most ECGs. However, pathologic Q waves are indicative of myocardial ischemia. Pathologic Q waves are generally diagnosed when they are >2 mm deep, >1 mm wide, >25% of the QRS complex height, or are seen in leads V1-V3. The interpretation of Q waves depends on other findings on ECG and the patient's symptoms. Deep Q waves in the setting of ST elevation indicate an acute myocardial infarction. On the other hand, pathologic Q waves found incidentally indicate a previous myocardial infarction or previous ischemic event.

Rovai et al. review Q waves. They discuss how Q waves can be used to predict the location and size of a myocardial infarction as correlated with MRI. They recommend testing such as cardiac MRI to assess for previous infarction in the appropriate patient population.

Figure/Illustration A is an ECG demonstrating pathologic Q waves (red arrows). Note the deep and wide Q waves; this raises concern for a past ischemic event.

Incorrect Answers:
Answer A: Acute myocardial infarctions would present with ST elevation in a vascular distribution on ECG with possible reciprocal depressions. While T wave inversions may be indicative of new or acute ischemia, deep pathologic Q waves without ST elevation are indicative of previous infarction.

Answer B: Hypokalemia would cause U waves on ECG, which appear as a small, "second T wave" after the initial T wave. Note they are not U-shaped despite their name. Management is centered on repletion of potassium and often magnesium as well.

Answer C: Intermittent torsades de pointes can cause syncope and should be suspected in a patient with syncope in the setting of a prolonged QT interval. This patient’s QT interval is not particularly prolonged, and his syncope seems to be secondary to orthostatic hypotension. Management is centered on cessation of QT-prolonging medications and magnesium administration. Note that while ondansetron does prolong the QT interval, it is unlikely to cause torsades given the patient took it a week ago.

Answer E: Pulmonary emboli would present on ECG with sinus tachycardia in addition to pleuritic chest pain and hypoxia. Note that the ECG is a nonspecific test for pulmonary emboli, and CT angiography is the preferred confirmatory test for this condition. Syncope is a possible presentation of larger pulmonary emboli (though the patient would also be hemodynamically unstable).

Bullet Summary:
Pathologic Q waves are indicative of a previous myocardial infarction.


Question: A 55-year-old man presents to his primary care physician with persistent symptoms of depression. He started taking fluoxetine 3 weeks ago when he was diagnosed with major depressive disorder after a divorce. Since then, he notes that his symptoms are roughly unchanged. His other medications include albuterol. His temperature is 99.3°F (37.4°C), blood pressure is 132/88 mmHg, pulse is 77/min, respirations are 14/min, and oxygen saturation is 99% on room air. Physical exam reveals a depressed affect. His neurologic exam is non-focal. A serum thyroid stimulating hormone (TSH) resulted from his last visit and is noted to be 4.8 µU/mL (normal: 0.5-5 µU/mL). Which of the following is the most appropriate next step in management?

Answer: Maintain dose of current medication

Explanation:
This patient is presenting with major depressive disorder but has not given his current selective serotonin reuptake inhibitor (SSRI) at least 4 weeks to begin working. Thus, he should be reassured and maintained on the current dose of his SSRI, with follow-up after the 4 week mark to see if his symptoms have improved.

Major depressive disorder is managed initially with cognitive behavioral therapy and pharmacotherapy. The typical first-line medication is an SSRI. SSRIs may take at least 4 weeks or more to begin working, so patients that return before this time period should be reassured and encouraged to let the medication take effect as long as they are not experiencing suicidal thoughts or intent. If the medication is not working after at least 4 weeks, the next steps in management could include increasing the dose of the current medication, changing SSRIs, adding another antidepressant agent, or adding a low dose of levothyroxine. All patients with suicidal ideation and either intent or a plan to hurt themselves should be hospitalized involuntarily.

Gautam et al. discuss the current management algorithms for major depressive disorder. They note different options including CBT and pharmacotherapy. They recommend appropriate treatment with a first-line agent based on the patient and their circumstances.

Incorrect Answers:
Answer A: Administering levothyroxine is appropriate as an augmenting agent in patients who do not have an improvement in symptoms on SSRIs or other antidepressants even if their TSH is within the normal range. However, it would not be attempted at this point given this patient has not given his current medication sufficient time to begin working. There is limited evidence to support its use overall. Note that this patient's TSH is within normal limits. In some cases, T3 administration is used in refractory depression.

Answer B: Changing the medication to bupropion could be appropriate in patients who want to avoid weight gain, those who want to quit smoking, or those who are trying to avoid sexual side effects. It also is an appropriate second-line agent or could be added to a first-line agent; however, this patient’s current medication should be tried for at least 4 weeks before changing medications.

Answers 3 & 4: Changing medication to escitalopram or increasing the dose of the current medication are both viable strategies if a patient has failed to improve on their first medication after at least 4 weeks on the medication. Increasing the dose early may lead to symptoms of serotonin excess when the drug takes effect.

Bullet Summary:
SSRIs are the first-line agents in the management of major depressive disorder and should be tried for at least 4 weeks before changing the treatment regimen.


Question: A 33-year-old man presents to the emergency department with dizziness. He states he has a constant sensation that the room is spinning. He is now having trouble walking and has been vomiting intermittently. He has no past medical history and takes no medications. His temperature is 98.0°F (36.7°C), blood pressure is 122/84 mmHg, pulse is 80/min, respirations are 16/min, and oxygen saturation is 98% on room air. Physical exam reveals a young man who is vomiting. His gait is ataxic and he exhibits rightward nystagmus. His dizziness is constant and unchanged with performance of the Dix-Hallpike maneuver. The head impulse test reveals a corrective saccade and there is no skew deviation. Which of the following is the most appropriate next step in management?

Answer: Prednisone

Explanation:
This young, healthy patient is presenting with constant vertigo, ataxia, vomiting, and a head impulse test revealing a corrective saccade, nystagmus, and test of skew (HINTS) exam, which suggests a peripheral etiology of vertigo, most likely vestibular neuritis. As the diagnosis can be made clinically, steroids are the only treatment needed.

Differentiating peripheral (the vestibular system) versus central (the brain) vertigo is critical in management. Peripheral vertigo is commonly caused by benign paroxysmal positional vertigo, vestibular neuritis, and labyrinthitis. Vertigo that is constant is more consistent with vestibular neuritis or labyrinthitis but could also be a cerebellar stroke. To differentiate, age, risk factors, and onset of symptoms are critical. Moreover, the HINTS exam can point toward 1 cause of vertigo versus another. HINTS is a mnemonic for: Horizontal head impulse testing (Head Impulse), Direction-changing nystagmus in eccentric gaze (Nystagmus), and Vertical skew (Test of Skew). Findings that are suggestive of a peripheral cause of vertigo include a positive head impulse exam, positive nystagmus (also seen in stroke), and a negative test of skew. In the appropriate clinical context with appropriate risk factors, peripheral causes such as vestibular neuritis or labyrinthitis can be managed with steroids (which may improve outcomes) and meclizine (for symptom control).

Kattah et al. discuss the HINTS exam. They note how it can be used to differentiate peripheral from central vertigo. It is recommended to perform this exam when differentiating central versus peripheral vertigo.

Incorrect Answers:
Answers 1 & 3: Head imaging such as a CT head or MRI brain is not necessary in patients with a clear peripheral cause of their vertigo/dizziness with a HINTS exam suggesting a peripheral etiology. Clinically, this patient has vestibular neuritis and can be treated accordingly. Imaging would be needed if the patient had an acute cerebellar stroke.

Answer D: The Epley maneuver is only indicated in cases of benign paroxysmal peripheral vertigo, which presents with severe vertigo (with changes in head position) that diminish with time and keeping the head stationary. Note that this patient’s Dix-Hallpike maneuver is negative and that his vertigo is constant rather than intermittent or positional.

Answer E: Tissue plasminogen activator is indicated within 4.5 hours in the setting of an ischemic stroke after a head CT rules out a head bleed, other reversible causes are treated, and assuming there are no contraindications to thrombolytics. Tissue plasminogen activator can be given in posterior circulation strokes.

Bullet Summary:
Peripheral causes of vertigo generally do not require head imaging, and causes such as labyrinthitis or vestibular neuritis can be treated with steroids.