Question 1

An 18-year-old man is on mechanical ventilation after sustaining severe head trauma in a motor vehicle collision.  The patient is unresponsive to various stimuli.  Blood pressure is 108/60 mm Hg and heart rate is 110/min.  After monitoring the patient for 24 hours, the physician decides to do a bedside assessment of brain death.  Which of the following can be observed in a patient with brain death?

Accepted Answer

Explanation: 11ec25c8_d553_84a9_bc81_61e18807212f_MD0003_00 This patient who sustained severe head injury and has been unresponsive to various stimuli for 24 hours may have sustained brain death. Brain death is defined as the irreversible cessation of all cerebral and brainstem activities and is a legally acceptable definition of death. In adults, the most common cause of brain death is traumatic brain injury. Brain death is a clinical diagnosis. Although specific criteria may vary by country or state, essential components for making the diagnosis of brain death typically include: Clinical criteria: evidence (eg, history, clinical, neuroimaging) of a devastating cause and absence of confounding factors (eg, hypothermia, intoxication, paralytics) Neurologic examination: coma and absence of all cerebral and brainstem activity, including cranial nerve reflexes (ie, brainstem reflexes) such as pupillary light reaction and oculovestibular reaction (Choices C and D). Motor responses originating in the brain, including purposeful movement, facial grimacing, and decerebrate/decorticate posturing, should also be absent. In contrast, movements originating in the spinal cord (eg, deep tendon reflexes such as the monosynaptic patellar reflex) may still be observed even if brain death is present. If the neurologic examination is consistent with brain death, the patient can be removed from the ventilator for an apnea test. A positive apnea test confirms brain death by documenting an absent respiratory response (ie, nonfunctioning medullary respiratory centers) to a PaCO₂ >60 mm Hg (or >20 mm Hg above baseline) and a final arterial pH <7.28 (Choice E). Sometimes additional confirmatory tests are used. ₂ confirmatory tests (Choice B) Atropine administration primarily increases heart rate by blocking the effects of the vagus nerve (ie, parasympathetic stimulation) on the heart. In brain death, vagal activity is already lost due to absent brainstem and cranial nerve function; therefore, additional vagal blockade (eg, atropine) typically has little effect on heart rate. Educational objective: Brain death, an irreversible loss of all brain function, is a clinical diagnosis based on clinical criteria and neurologic examination. Essential findings include coma, absent cranial nerve reflexes and brain-originating motor responses, and apnea. Movements originating in the spinal cord (eg, deep tendon reflexes) may be present. References: Diagnosis of brain death. (http://www.ncbi.nlm.nih.gov/pubmed/21577338) The diagnosis of brain death. (http://www.ncbi.nlm.nih.gov/pubmed/19881172) Performing the brain death examination and the declaration of pediatric brain death. (http://www.ncbi.nlm.nih.gov/pubmed/31073455) Ancillary studies in evaluating pediatric brain death. (http://www.ncbi.nlm.nih.gov/pubmed/31073456)

Question 2

A 35-year-old man comes to the office with a 5-day history of back pain, which began as he was carrying heavy boxes while moving to a new apartment. Since then, he has had sharp pain in the low back radiating to the posterior aspect of the left calf and foot. The patient has no associated bladder or bowel incontinence. Vital signs are normal. BMI is 38 kg/m². Examination shows intact motor strength, deep tendon reflexes, and light touch and pinprick sensation in the lower extremities. Anal reflex and perineal sensation are normal. Lifting the left leg to 70 degrees with the knee held straight causes burning pain radiating from the low back to the left foot. Which of the following is the best next step in management?

Accepted Answer

11ec25c8_d54b_e381_bc81_7dae110e45d9_MD0003_00 This patient has acute lumbosacral radiculopathy (LSR), also termed sciatica. LSR is most commonly caused by nerve root compression due to a herniated disc. Older patients or those with prior traumatic injury can also have nerve root compression due to lumbar spondylosis. Less common causes include infections (eg, epidural abscess), mass lesions, vascular disorders, and developmental anomalies. Patients typically experience shooting or burning pain in the low back radiating to the calf and foot; minor weakness can occur. Traction on the nerve root during the straight-leg raising test (ie, lifting the leg with the patient supine and the knee held in extension) causes worsening or reproduction of pain. nerve root compression The diagnosis is made clinically; because nearly all cases are due to benign etiologies and symptoms are typically self-limiting, neuroimaging is usually not required. MRI is recommended only for patients with severe, progressive, or bilateral neurologic deficits (eg, saddle anesthesia, urinary retention, severe weakness) or in those with high concern for malignancy or epidural abscess (eg, fever, intravenous drug use). In uncomplicated LSR, like that in this patient, initial management focuses primarily on alleviating symptoms. Nonsteroidal anti-inflammatory drugs and acetaminophen are the preferred first-line drugs. Activity modification is often advisable, but patients should maintain moderate physical activity. (Choices A and F) MRI can confirm disc herniation or other causes of LSR but is expensive and unlikely to change management in a patient with uncomplicated LSR (no neurologic deficits or history of malignancy). X-ray is considered for nonradicular back pain due to compression fracture or suspected vertebral metastasis but has limited use in LSR. (Choice B) Electrodiagnostics (eg, nerve conduction studies) are indicated for patients with persistent neurologic deficits, especially those who are being considered for surgery or have had previous spinal surgery. (Choice C) Physical therapy referral for a supervised exercise program can be considered for patients with persistent pain lasting more than a few weeks. However, the effectiveness is variable, and most patients with acute symptoms experience spontaneous improvement. (Choice D) Surgical intervention is indicated for patients with rapidly progressive neurologic deficits or severe, persistent symptoms who have not responded to conservative measures. Educational objective: Lumbosacral radiculopathy (sciatica) is due to nerve root compression, usually by a herniated disc or lumbar spondylosis. Most patients experience spontaneous resolution. Initial management is focused primarily on short-term relief of symptoms with nonsteroidal anti-inflammatory drugs or acetaminophen. References: Comparative clinical effectiveness of management strategies for sciatica: systematic review and network meta-analyses. (http://www.ncbi.nlm.nih.gov/pubmed/24412033)

Question 3

A 60-year-old man comes to the office for evaluation of gait imbalance, which he has had for the past 3 days. The patient was hospitalized 2 weeks ago for a complicated enterococcal diabetic infection of the left foot. He was prescribed ampicillin and gentamicin, which he has continued via home intravenous antibiotic therapy. The patient subsequently developed a constant sensation of objects moving around in his visual field when looking in any direction, which has caused him to feel unsteady. He has no associated nausea or vomiting. The patient has a history of poorly controlled type 2 diabetes mellitus and hypertension. His other medications include lisinopril and basal-bolus insulin therapy. Temperature is 36.7 C (98 F), blood pressure is 140/96 mm Hg, pulse is 80/min, and respirations are 16/min. BMI is 34 kg/m². The left foot wound is healing without discharge or surrounding erythema. Neurologic examination shows 5/5 muscle strength and 2+ reflexes in all extremities. Hearing is decreased in the right ear on whisper test. Rapid head movement away from a fixed target causes eye movement away from the target followed by a horizontal saccade back toward it. Which of the following is the most likely cause of this patient's current symptoms?

Accepted Answer

Explanation: This patient who was recently prescribed gentamicin now has new-onset hearing loss, imbalance, and a sensation of objects moving (oscillopsia). This presentation is consistent with aminoglycoside ototoxicity. The risk of aminoglycoside ototoxicity is increased in patients with bacteremia, hepatic or renal dysfunction, or when used in combination with another potentially ototoxic medication. Aminoglycoside ototoxicity can damage hair cells in the cochlea (causing hearing loss) and/or the vestibular system (causing imbalance). Therefore, patients have varying clinical features, including the following: Bilateral, but not necessarily symmetric, hearing loss (as evidenced by this patient's right > left screening whisper test). Patients with a positive whisper test require a formal audiogram. Imbalance and oscillopsia because bilateral vestibular systems are affected (rather than true vertigo, which generally occurs when 1 side is affected). A positive head thrust test (ie, inability to maintain visual fixation during forced, rapid head movement). This test evaluates the vestibuloocular reflex, which is affected by peripheral but not central vestibulopathies, as seen in this patient. Management of patients with aminoglycoside toxicity requires immediate discontinuation of the medication to prevent further damage. (Choice A) In contrast to this patient, those with benign paroxysmal positional vertigo (BPPV) have brief (<1 minute), episodic vertigo stimulated by specific head movements (eg, rolling over in bed, looking up). In addition, BPPV is not associated with hearing loss and is confirmed with the Dix-Hallpike maneuver (vertigo and nystagmus on quickly lying back into a supine position with the head rotated 45 degrees) rather than the head thrust test. Dix-Hallpike maneuver (Choices B and F) This patient has risk factors for cerebellar stroke and vertebrobasilar insufficiency, which can cause gait imbalance. However, these cause central vertigo and therefore would have a preserved head thrust and no hearing loss. (Choice C) Poorly controlled diabetes can cause autonomic dysfunction (eg, gait imbalance, "dizziness" while standing) due to postural hypotension. However, it does not cause a positive head thrust test, oscillopsia, or hearing loss, making this diagnosis unlikely. (Choice E) Ménière disease is an inner ear disorder characterized by increased endolymph volume and/or pressure (endolymphatic hydrops). It presents with discrete episodes of spinning vertigo (vs constant sensation in this patient) accompanied by hearing loss (which can be progressive) as well as tinnitus or aural fullness (not seen in this patient). In addition, the timeline of symptoms shortly after aminoglycoside therapy makes drug toxicity much more likely. Educational objective: Aminoglycosides can be ototoxic to both the cochlea (resulting in sensorineural hearing loss) and the vestibular system (resulting in imbalance). References: Clinical diagnosis of bilateral vestibular loss: three simple bedside tests. (http://www.ncbi.nlm.nih.gov/pubmed/23277792) Horizontal head impulse test detects gentamicin vestibulotoxicity. (http://www.ncbi.nlm.nih.gov/pubmed/19380701) Hearing loss in patients with vestibulotoxic reactions to gentamicin therapy. (http://www.ncbi.nlm.nih.gov/pubmed/16549744)

Question 4

A 28-year-old woman comes to the emergency department due to bilateral upper extremity weakness and abdominal pain.  The patient has had progressive weakness of the upper extremities for 2 days and severe, diffuse, poorly localized abdominal pain for 1 day.  Temperature is 37.3 C (99.1 F), blood pressure is 148/86 mm Hg, and pulse is 112/min.  On physical examination, the patient appears restless and is diaphoretic.  There is no scleral icterus.  The abdomen is soft and nontender, with no organomegaly, guarding, or rebound tenderness.  Bowel sounds are decreased.  Neurological examination shows normal cranial nerves, weakness of the proximal upper extremity muscles, and loss of the biceps and triceps reflexes on both sides.  Laboratory results are as follows:  Which of the following is most likely to yield the diagnosis in this patient?

Accepted Answer

Explanation: 11ec25c8_d54e_2d76_bc81_952a6bb93946_MD0003_00 This patient with diffuse abdominal pain, peripheral neuropathy (eg, upper extremity weakness, areflexia), and positive urobilinogen most likely has acute intermittent porphyria (AIP). AIP is an autosomal dominant disorder of the heme synthesis pathway that results in reduced activity of porphobilinogen deaminase, leading to buildup of neurotoxic heme pathway intermediates (ie, porphobilinogen, aminolevulinic acid). heme synthesis pathway Patients typically experience discrete attacks after exposure to certain triggers, including medications (eg, progesterone-containing drugs), tobacco, alcohol, and physiologic stressors (eg, surgery, fasting); however, the trigger may not always be identified. Manifestations are related to neurotoxicity in various organ systems and include: Abdominal pain: Because the pain is neuropathic, it can be diffuse, although tenderness, rebound, and guarding are absent. Nausea/vomiting, hypoactive bowel sounds, and constipation may occur. Peripheral neuropathy: Most prominent in the proximal upper extremities Autonomic dysfunction (eg, tachycardia, diaphoresis, tremor) Neuropsychiatric manifestations (eg, restlessness, hallucinations) Unlike other porphyrias (eg, porphyria cutanea tarda), photosensitive cutaneous findings are absent. Hyponatremia may occur due to syndrome of inappropriate antidiuretic hormone. Urinary porphyrins and porphobilinogen results in red-tinged urine (ie, positive for urobilinogen, negative for blood) that darkens when exposed to air and light. Elevated urinary porphyrin levels confirm the diagnosis. when exposed to air and light (Choice A) Lead poisoning also results in abdominal pain and neuropsychiatric manifestations; however, patients typically have fatigue, joint pain, and anemia. Hyponatremia and dysautonomia is unexpected. (Choice B) On cerebrospinal fluid (CSF) analysis, albuminocytologic dissociation (elevated CSF protein with normal CSF leukocyte count) is classically seen in Guillain-Barré syndrome, which typically occurs after a gastrointestinal illness and presents with ascending weakness. Elevated urobilinogen is unexpected. (Choice C) JAK2 mutations are common in myeloproliferative disease (eg, polycythemia vera), which can cause portal vein thrombosis that leads to abdominal pain and may occasionally be associated with sensorineural neuropathy. However, blood cell counts would be abnormal (eg, elevated hemoglobin). (Choice D) Mesenteric angiography can be used to diagnose polyarteritis nodosa, which also causes abdominal pain and mononeuritis multiplex; however, renal failure, skin manifestations (eg, tender nodules), and constitutional symptoms (eg, fever, fatigue) are typical. (Choice E) Serum ceruloplasmin is often low in Wilson disease, which can cause neuropsychiatric symptoms and abdominal pain related to hepatitis. However, patients typically have elevated liver function studies, hepatomegaly, and Kayser-Fleischer rings on examination. Educational objective: Acute intermittent porphyria is a disorder of the heme synthesis pathway that results in reduced activity of porphobilinogen deaminase. Patients experience discrete attacks of abdominal pain, peripheral neuropathy with proximal muscle weakness, autonomic dysfunction, and neuropsychiatric manifestations. Urobilinogen levels are typically elevated, and elevated urinary porphyrin levels confirm the diagnosis.

Question 5

A 35-year-old man comes to the emergency department due to severe pain behind his left eye.  The patient reports that the pain is intense and stabbing and that it woke him up around midnight.  It improved after 30 minutes and he was about to go back to sleep when the same pain began again.  He took ibuprofen without relief.  Several months ago, the patient had similar episodes of pain that resolved spontaneously after 2 weeks.  He has had no fevers, blurry vision, nausea, or vomiting but has had nasal congestion.  The patient has seasonal allergies for which he takes cetirizine.  He works as a flight operations officer and describes his job as "pretty stressful."  He drinks 2 or 3 cups of coffee daily and drinks alcohol occasionally.  His mother has migraine headaches.  Temperature is 36.7 C (98 F), blood pressure is 140/90 mm Hg, and pulse is 94/min.  The patient is restless and agitated.  Physical examination shows left-sided ptosis, miosis, and rhinorrhea.  Neurologic examination shows bilateral equal and normal motor strength, sensation, and deep tendon reflexes.  Which of the following is the most likely cause of this patient's headache?

Accepted Answer

11ec25c8_d549_998e_bc81_81e6bb7c457f_MD0003_00 This patient with episodes of acute left retro-orbital pain accompanied by ipsilateral autonomic manifestations (eg, ptosis, miosis, rhinorrhea) likely has cluster headaches. These headaches are generally seen in young men, are unilateral, and can be accompanied by redness of the ipsilateral eye with tearing but no visual changes, as well as by agitation due to the severity of the pain. The autonomic manifestations may be similar to those seen with Horner syndrome (ptosis, miosis, anhidrosis). The paroxysms of cluster headache attacks begin during sleep, peak rapidly, last approximately 90 minutes, and occur up to 8 times daily for 6-8 weeks followed by a remission lasting up to a year. Because the attacks are short but severe, prophylactic medication (eg, verapamil, lithium) is important for management. An acute attack can be aborted with inhalation of 100% oxygen or with subcutaneous sumatriptan. (Choices A and G) Acute maxillary sinusitis can present with facial pain and rhinorrhea, but there is usually associated fever and anosmia. Orbital cellulitis is an infection of the fat and extraocular muscles of the eye. Patients usually have erythema, edema, and tenderness, often with impaired extraocular movement. These conditions generally do not cause paroxysms of severe retro-orbital pain or miosis. Orbital cellulitis (Choice B) Angle closure glaucoma usually presents with sudden-onset eye pain, nausea, and diminished vision with halos seen around lights. Patients typically have a fixed and mid-dilated pupil and not ptosis or miosis. Angle closure glaucoma (Choices C, E, and I) A brain tumor typically presents with progressive headache, morning nausea, and focal neurologic deficits due to mass effect. A lacunar infarction can have a range of syndromic presentations (eg, pure motor hemiparesis, ataxic-hemiparesis, dysarthria/clumsy hand). A subarachnoid hemorrhage is characterized by sudden-onset, persistent, severe headache that can be associated with vomiting, seizure, and a decreased level of consciousness. None of these conditions would cause recurrent severe retro-orbital pain in a young patient. (Choices F, K, and L) Migraines are usually associated with nausea, vomiting, and photophobia; these headaches are typically pulsatile and throbbing rather than sharp and severe. Tension-type headaches can occur due to stress but are usually non-throbbing and bilateral. Trigeminal neuralgia is characterized by recurrent and sudden-onset stabbing pain along the V2 (maxillary) and V3 (mandibular) branches of the trigeminal nerve. The episodes last a few seconds to minutes and can be triggered by minor stimuli (eg, wind). Ptosis, miosis, and rhinorrhea are more suggestive of cluster headache. trigeminal nerve (Choice H) A retinal detachment typically presents with light flashes, floaters, or a curtain across the visual field that usually starts from the periphery and is generally not painful. retinal detachment floaters curtain (Choice J) Substance use disorder can present with agitation and restlessness, but it does not usually present with unilateral ptosis and miosis or with sudden-onset and recurrent retro-orbital eye pain. Educational objective: Cluster headaches usually present with acute, unilateral, severe retro-orbital pain that awakens patients from sleep. These headaches may be accompanied by redness and tearing, rhinorrhea, and ipsilateral ptosis and miosis. References: Cluster headache. (http://www.ncbi.nlm.nih.gov/pubmed/22496300) The international classification of headache disorders, 3rd edition (beta version). (http://www.ncbi.nlm.nih.gov/pubmed/23771276)

Question 6

A 35-year-old man is brought to the emergency department after crashing his motorcycle into a guardrail at high speed.  He was riding without a helmet and briefly lost consciousness, but he is now awake and alert in the emergency department.  Blood pressure is 120/70 mm Hg and pulse is 96/min.  The patient is wearing a cervical collar and his breath smells of alcohol.  Bilateral pupils are equal and reactive.  There is chest wall bruising and tenderness.  Heart and breath sounds are normal.  The abdomen is soft and nontender.  There is an obvious deformity of the right leg.  Neurological examination shows bilateral lower extremity weakness.  Light touch and vibratory sensation is present in both legs, but there is loss of pain and temperature sensation.  Bilateral upper extremity motor and sensory examination is normal.  Injury at which of the following sites is the most likely cause of this patient's neurological deficits?

Accepted Answer

Explanation: 11ec25c8_d552_2517_bc81_4d102e33f9e9_MD0003_00 This patient with neurological deficits after a motorcycle crash likely has anterior cord syndrome. This usually occurs when there is an injury to the anterior spinal artery (eg, disc retropulsion, fragments of bone from vertebral burst fracture) affecting the anterior two thirds of the spinal cord. Neurological findings include: Bilateral hemiparesis: Lateral corticospinal tract; at the level of the cord injury and below Diminished bilateral pain and temperature sensation: Lateral spinothalamic tract (LST); 1-2 levels below the cord injury because LST decussates 1-2 levels before the corresponding level Intact bilateral proprioception, vibratory sensation, and light touch: Dorsal columns; blood is supplied from the posterior spinal arteries, which are bilateral and reinforced by radicular segmental branches In this patient, bilateral upper extremity motor and sensory examination is normal, which indicates that the level of injury is likely below T1, based on the dermatomes that innervate the arms. This patient should immediately have an MRI to assess the injury site, and likely needs a decompressive procedure to regain neurological function. dermatomes (Choice B) Central cord syndrome is characterized by decreased sensation and motor function in the arms with relative sparing of the legs after forced hyperextension (eg, fall, whiplash); it can be associated with bladder dysfunction. It is usually seen in the elderly with underlying cervical spondylotic myelopathy. (Choice C) An injury to the frontoparietal lobes is likely to cause ongoing altered consciousness, and alone is unlikely to cause bilateral lower extremity weakness with sensory changes. (Choice D) A spinal nerve root injury affecting the lower extremities is more likely to cause a unilateral sciatica-type presentation of back pain, changes in sensation, and motor weakness in one extremity rather than in both. (Choice E) Ventral brainstem injury can lead to "locked-in" syndrome, a disorder characterized by quadriplegia and the inability to speak or swallow but with normal consciousness. Patients can usually blink voluntarily and look vertically due to sparing of the supranuclear ocular pathway. Educational objective: Anterior cord syndrome usually occurs when there is injury to the anterior spinal artery from trauma. It is characterized by bilateral motor function loss at and below the level of the injury with diminished pain and temperature sensation bilaterally that begins 1-2 levels below the cord injury, whereas proprioception, vibratory sensation, and light touch are unaffected. References: Characterization of spinal injuries sustained by American service members killed in Iraq and Afghanistan: a study of 2,089 instances of spine trauma. (http://www.ncbi.nlm.nih.gov/pubmed/23511153) [Pathophysiology of acute spinal cord injury]. (http://www.ncbi.nlm.nih.gov/pubmed/16607070)

Question 7

A 74-year-old woman is brought to the office by her daughter due to behavioral changes. Over the past month, the patient has become more withdrawn. She no longer watches her favorite television shows and seems less interested in her family. The daughter has noticed increasing forgetfulness over the past 3 years but assumed it "comes with aging." Over the past year, the patient has stopped doing the daily crossword, has had difficulty remembering to eat and clean herself, and has occasionally failed to recognize her grandchildren. Montreal Cognitive Assessment is 22/30 (normal: ≥26). Serum TSH and vitamin B₁₂ levels are normal. Which of the following is the most appropriate next step in management of this patient?

Accepted Answer

Dementia (also known as major neurocognitive disorder) may be diagnosed in patients with progressive cognitive decline that impairs activities of daily living (eg, bathing, dressing, preparing meals). The most common subtype of dementia is Alzheimer disease (AD), which typically presents with prominent but relatively isolated impairments in memory early in the disease course. As AD progresses, apathy, social withdrawal, and loss of interest in activities frequently develop and can mimic depression. This patient's 3-year history of cognitive decline preceding the development of behavioral symptoms is most consistent with AD. Although the etiology of AD is not well understood, histopathologic examination of brain tissue in affected patients indicates a selective loss of cholinergic neurons. The first-line treatment for cognitive symptoms of AD is a cholinesterase inhibitor, which may improve quality of life and cognitive function (eg, memory, language, thought, reasoning), although drugs in this class have not been shown to alter the disease course in any type of dementia. Donepezil, galantamine, and rivastigmine are effective in patients with mild to moderate AD. Memantine, an NMDA receptor antagonist, is approved for moderate to severe dementia. (Choice A) Amantadine, thought to possess dopaminergic and NMDA receptor antagonist properties, is frequently used in the treatment of Parkinson disease. The evidence of its benefit in the treatment of AD is limited and it would not be considered as a first-line treatment in this patient. (Choice B) Fluoxetine is an antidepressant used in the treatment of depression. Depression may present with cognitive impairment that can, if severe enough, masquerade as dementia. However, this patient does not meet criteria for major depressive disorder, and she experienced cognitive deficits and related functional impairment (eg, forgetfulness, difficulty recognizing relatives) years before the onset of any depressive-like symptoms (eg, social withdrawal, decreased interest), making AD more likely. Depressive symptoms are commonly seen as AD progresses. major depressive disorder (Choice D) Selegiline is a monoamine oxidase inhibitor that is sometimes used as a second-line treatment in AD for its antioxidant properties, although current evidence is weak. (Choice E) This patient is already experiencing cognitive decline sufficient to impair functioning. As a result, reassurance and follow-up, without consideration of a trial of a cholinesterase inhibitor, are inappropriate. Educational objective: Cholinesterase inhibitors such as donepezil, rivastigmine, and galantamine may provide moderate symptomatic relief of cognitive symptoms and temporarily improve functioning in Alzheimer disease; however, these medications have not been shown to alter the disease course. References: Current pharmacotherapy and putative disease-modifying therapy for Alzheimer's disease. (http://www.ncbi.nlm.nih.gov/pubmed/27250365)

Question 8

A 63-year-old man comes to the emergency department due to sudden-onset right-sided weakness that resolved spontaneously within 30 minutes.  Medical history includes hypertension and an early-stage sigmoid colon cancer that was resected 5 years ago; follow-up colonoscopy showed no recurrence.  The patient takes lisinopril.  He has a 20-pack-year history and quit smoking 10 years ago.  Blood pressure is 130/80 mm Hg and pulse is 74/min.  Examination shows a left carotid bruit.  Neurologic examination is normal.  ECG shows normal sinus rhythm.  CT scan of the head is normal.  Lipid panel results are as follows:  Echocardiography is unremarkable.  Carotid duplex ultrasonography and follow-up CT angiography show 80% stenosis in the left internal carotid and 40% stenosis in the right internal carotid artery.  Which of the following is the most appropriate next step in preventing a further stroke in this patient?

Accepted Answer

Explanation: 11ec25c8_d548_39fd_bc81_c13b931388b7_MD0003_00 This patient with temporary right-sided motor weakness without evidence of infarction on MRI had a transient ischemic attack (TIA), and subsequent evaluation for a source demonstrated 80% stenosis of the left carotid artery. Without intervention, patients such as this one with symptomatic carotid atherosclerotic disease-defined as causing sudden, focal neurologic symptoms attributable to the distribution of the affected vessel within the previous 6 months-are at high risk of stroke within the first year. Therefore, all such patients should receive intensive medical therapy (ie, aspirin, statin, blood pressure control), counseling on lifestyle changes (eg, exercise, smoking cessation), and evaluation for carotid revascularization. In patients with symptomatic disease, the recommendation for carotid revascularization depends on the degree of stenosis: 70%-99% stenosis: Revascularization with carotid endarterectomy (CEA) is generally recommended. 50%-69% stenosis: Revascularization is likely beneficial for men; its benefit has not been proven in women, so medical management alone is recommended for women. <50% stenosis: CEA has no proven benefit and is not recommended. Other factors, including the presence of persistent disabling neurologic defects or a short life expectancy (eg, <5 years), are also considered when analyzing benefits versus risks for CEA in an individual patient. Carotid artery stenting (CAS) may be a revascularization alternate to CEA in select patients but has a higher periprocedural (ie, 30-day) risk of stroke and death. (Choices A and E) CEA has not shown benefit for carotid stenosis <50%, whether symptomatic or asymptomatic. Therefore, revascularization is not recommended for this patient's right carotid artery, which has only 40% stenosis. (Choices C and D) Medical therapy (eg, aspirin, statin, blood pressure control) should be initiated in all patients with carotid atherosclerotic disease. However, anticoagulation (eg, heparin, oral anticoagulant) is less effective than antiplatelet therapy (eg, aspirin) for secondary prevention of stroke in patients with carotid stenosis unless there is an alternate indication for anticoagulation (eg, atrial fibrillation). Educational objective: All patients with carotid atherosclerotic disease should receive intensive medical management (ie, aspirin, statin, blood pressure control) and counseling on lifestyle changes to reduce future stroke risk. Carotid endarterectomy is also generally recommended for patients with symptomatic stenosis of 70%-99%. References: Treatment of carotid stenosis. (http://www.ncbi.nlm.nih.gov/pubmed/23259569) Evaluation and management of atherosclerotic carotid stenosis. (http://www.ncbi.nlm.nih.gov/pubmed/28688468)

Question 9

A 68-year-old woman comes to the office due to persistent right-sided chest pain.  The patient has had burning pain on the right chest wall and back for the past several months.  She has had no associated cough, dyspnea, or trauma but had a transient rash in the same region prior to the onset of symptoms.  Medical history is notable for breast cancer treated with surgery and chemotherapy, as well as hypertension and type 2 diabetes mellitus.  Temperature is 37.1 C (98.8 F), blood pressure is 130/80 mm Hg, and pulse is 82/min.  Chest examination shows no skin rash, but there is a band-like area of hyperesthesia on the right side.  Lung auscultation reveals prolonged expiration with no wheezes.  Heart sounds are normal.  Back examination shows no deformity or focal tenderness.  Which of the following is the best next step in management of this patient?

Accepted Answer

11ec25c8_d54a_83ef_bc81_e30e5e52206c_MD0003_00 This patient had a self-limited rash on the trunk (likely herpes zoster) and now has continued burning pain and hyperesthesia in the area of the rash, suggesting postherpetic neuralgia (PHN). Acute zoster (shingles) is due to reactivation of the varicella zoster virus (VZV) and causes transient pain due to hemorrhagic inflammation of the sensory nerve. As viral replication diminishes, the skin lesions resolve and the pain typically fades; however, persistent pain for >4 months indicates PHN. PHN occurs in approximately 5% of patients with shingles. The risk is greatest in those with advanced age, severe initial pain, or severe rash. The pain may be constant or intermittent and is typically associated with allodynia (pain elicited by nonpainful stimuli [eg, light touch]). Physical examination often reveals sensory abnormalities (eg, anesthesia, hyperesthesia) in the affected dermatome. PHN often improves over time, but resolution may take years and the severity of pain usually warrants pharmacologic treatment. Anticonvulsants (primarily gabapentin and pregabalin) and tricyclic antidepressants (eg, amitriptyline) are the best-established drugs. Topical capsaicin and lidocaine are options for patients with mild to moderate pain. Opioids (eg, oxycodone) are also effective but are not preferred due to the expected duration of treatment and potential for dependence and abuse. (Choice B) Systemic glucocorticoids (eg, prednisone) may decrease the pain of acute shingles but are not useful in prevention or treatment of PHN. Rarely, intrathecal glucorticoid therapy may be considered for patients with severe, refractory PHN symptoms. (Choice C) MRI is useful to evaluate radiculopathy, which can cause burning pain in a dermatomal distribution but is significantly less common in the thoracic spine than in other spine segments. The diagnosis of PHN is based primarily on the temporal relation between the dermatomal rash and the subsequent pain; imaging is not usually helpful. (Choice D) Chest x-ray may identify a pleural effusion due to pleuritis or pleural metastases, which could cause chest pain. However, this patient has no cough, dyspnea, or examination findings (eg, asymmetrical breath sounds) to suggest an effusion, and her burning pain, hyperesthesia, and rash history are more consistent with PHN. VZV pneumonia (due to viral spread) can occur but typically presents at around the same time as the rash and is associated with respiratory symptoms. (Choice E) Antiviral therapy (eg, valacyclovir) can shorten the course of acute shingles and reduce the risk of PHN. However, PHN is not associated with ongoing viral replication, and antiviral therapy has no benefits. Educational objective: Postherpetic neuralgia is characterized by burning pain and hyperesthesia lasting >4 months following acute zoster. The risk is greatest in those with advanced age, severe initial pain, or severe rash. First-line treatment includes anticonvulsants (eg, gabapentin) and tricyclic antidepressants (eg, amitriptyline). References: Gabapentin for chronic neuropathic pain in adults. (http://www.ncbi.nlm.nih.gov/pubmed/28597471)

Question 10

A 68-year-old man with chronic obstructive pulmonary disease (COPD) experiences progressive dyspnea, wheezing, and cough over several days despite using inhaled glucocorticoids and bronchodilators.  His shortness of breath rapidly worsens and emergency medical services (EMS) is called.  The patient becomes unresponsive prior to EMS arrival and is found to have pulseless electrical activity.  Cardiopulmonary resuscitation is begun, and he is endotracheally intubated.  The patient regains spontaneous circulation on arrival to the emergency department and is found to have a large pneumothorax and exacerbation of COPD.  His other medical conditions include hypertension, type 2 diabetes mellitus, and Parkinson disease.  A chest tube is inserted, and the patient is admitted to the intensive care unit for further management.  Over the next several days, his respiratory status gradually improves, but he remains unresponsive despite not receiving any sedation.  The patient is also observed to have recurrent episodes of brief contractions of various muscle groups.  Deep tendon reflexes are normal.  Serum electrolytes are within normal limits.  Which of the following is the most likely cause of the observed findings in this patient?

Accepted Answer

Explanation: Myoclonus is characterized by sudden, involuntary muscle contraction or relaxation that results in movement of limbs or joints. It can occur due to genetic disorders, seizures, medications, or prolonged hypoxia. This patient likely has posthypoxic myoclonus (PHM), a form of secondary myoclonus that commonly occurs after cardiac arrest. PHM can be subdivided into acute and chronic forms: Myoclonus status epilepticus (MSE) is the acute form of PHM that typically develops within 24 hours after the initial hypoxic insult while the patient is still unconscious. It is characterized by a generalized (often symmetric) myoclonus that typically involves the axial, limb, and facial muscles; intermittent eye opening, upward gaze deviation, and swallowing movements are also common. Persistent MSE is considered a marker of poor prognosis. Lance-Adams syndrome, the chronic form of PHM, presents days to weeks after the initial insult once the patient has regained consciousness. It is typically focal in nature and exacerbated by action; negative (relaxation) myoclonus also occurs, leading patients to drop objects or fall. An electroencephalogram should be obtained to help distinguish between other forms of seizure and PHM. The management of both the acute and chronic forms of PHM involves administration of antiepileptic agents (eg, clonazepam, levetiracetam) and supportive care. (Choice A) Critical illness polyneuropathy commonly occurs after a prolonged stay in the intensive care unit but is characterized by peripheral weakness and reduced reflexes. (Choice B) Medications such as statins and colchicine can be myotoxic and result in rhabdomyolysis. In addition, prolonged immobility due to the therapeutic use of paralytic agents can lead to compression of muscles, causing ischemia and necrosis. However, symptoms include muscle tenderness and weakness, not myoclonus. (Choice C) Antipsychotic (eg, haloperidol) or antiemetic medications (eg, metoclopramide) can cause extrapyramidal side effects, resulting in involuntary muscle group contraction (ie, dystonia) or motor restlessness (akathisia). However, akathisia would only occur in awake patients, and dystonias typically result in sustained contractions that are usually quite distinguishable from myoclonus (eg, torticollis, chorea). (Choice D) Muscle denervation can occur in neurodegenerative diseases such as amyotrophic lateral sclerosis, postpolio syndrome, and spinobulbar muscular atrophy, resulting in fasciculations rather than myoclonus. Fasciculations usually result only in visible twitching of muscles without movement of joints. Educational objective: Myoclonus is characterized by sudden, involuntary muscle contraction or relaxation that results in movement of limbs or joints. Posthypoxic myoclonus is often seen after cardiac arrest; the acute form (myoclonus status epilepticus [MSE]) occurs while patients are still unconscious and is characterized by generalized (often symmetric) myoclonus that involves the axial, limb, and facial muscles. Prolonged MSE is a marker of poor prognosis. References: Post-hypoxic myoclonus: current concepts, neurophysiology, and treatment. (http://www.ncbi.nlm.nih.gov/pubmed/27708982) Post-hypoxic myoclonus: differentiating benign and malignant etiologies in diagnosis and prognosis. (http://www.ncbi.nlm.nih.gov/pubmed/30214979)

Question 11

A 36-year-old woman comes to the emergency department due to left-sided facial droop. The patient woke up 4 hours ago and noticed that the left side of her face was sagging and that she was drooling from a corner of the mouth. She has had no facial numbness but has noticed an increased sensitivity to noise. The patient has a history of migraines, seasonal allergies, and gestational diabetes. Temperature is 36.5 C (97.7 F), blood pressure is 120/70 mm Hg, and pulse is 78/min. BMI is 32 kg/m². The face appears asymmetric with loss of the left nasolabial fold. When the patient is asked to smile, the left side of her face does not move. She is unable to raise her left eyebrow or completely close her left eye. Facial sensation to touch and pain is normal bilaterally. There are no skin or mucous membrane lesions. Which of the following is the most likely cause of this patient's current condition?

Accepted Answer

11ec25c8_d552_c158_bc81_cb33ad1a5f69_MD0003_00 This patient likely has Bell palsy, a peripheral neuropathy involving cranial nerve (CN) VII (facial nerve). Characteristic features include unilateral mouth drooping, disappearance of the nasolabial fold, and, importantly, involvement of the upper face (eg, weakness in closing the eye or raising the eyebrow). Upper face involvement distinguishes Bell palsy from upper motor neuron disorders (eg, stroke), which spare the upper face. Other common symptoms of Bell palsy include decreased ipsilateral eye lacrimation, hyperacusis, and decreased sensation of taste over the anterior two-thirds of the ipsilateral tongue. The weakness typically develops acutely over a course of hours; however, it often occurs at night, and patients may awaken with significant facial droop. Symptoms typically progress over 2-3 weeks, with gradual improvement over the following 3-6 months. Bell palsy is thought to be due to reactivation of a neurotrophic virus, most commonly herpes simplex virus. Viral infection causes inflammation and edema of the facial nerve, resulting in nerve compression and degeneration of the myelin sheath. Treatment involves glucocorticoids; because of the association with herpes simplex virus, some experts also recommend the addition of valacyclovir. (Choice A) Migraine with aura involving the brainstem (basilar migraine) manifests with vertigo, dysarthria, diplopia, and possibly loss of consciousness, typically followed by a severe occipital headache. Facial weakness would be unexpected. (Choice B) The corticobulbar tract carries input from upper motor nuclei and innervates CN V, VII, IX, X, XI, and XII. Most of these CNs receive bilateral cortical input and are unaffected by a unilateral lesion (ie, stroke). However, the neurons of CN XII that innervate the genioglossus muscle (tongue) and the neurons of CN VII that innervate the lower face only receive unilateral input. Therefore, stroke involving the corticobulbar tract results in lower facial weakness with sparing of the forehead (due to bilateral innervation of the upper forehead) and tongue deviation. bilateral innervation (Choice C) Microvascular ischemia of a cranial nerve is usually seen in patients with uncontrolled diabetes (diabetic mononeuropathy) or hypertension. Although it can cause a facial nerve palsy similar to Bell palsy, it is highly unlikely in this patient without comorbid diabetes or hypertension. (Choice E) Multiple sclerosis causes patchy demyelination; however, suprapontine lesions in the white matter would result in an upper motor neuron lesion. Patients would have lower facial weakness but the forehead would be spared. Educational objective: Bell palsy is a peripheral neuropathy of the facial nerve (cranial nerve VII) characterized by facial weakness that involves both the upper and lower face. It is thought to be caused by reactivation of neurotrophic viruses (eg, herpes simplex virus), resulting in inflammation, edema, and degeneration of the myelin sheath.

Question 12

A 33-year-old woman comes to the office due to intermittent dizziness.  The patient describes a sensation of severe spinning accompanied by intense nausea that lasts 1-2 hours.  She feels unsteady during these episodes and has to lie down with her eyes closed for relief.  The patient has had several similar episodes during the past 2 years but has not noted any factors that precipitate the symptoms.  She also hears a "mechanical humming" sound in her right ear during these episodes.  The patient has no associated headaches, ear pain, or ear discharge.  Temperature is 36.6 C (98 F), blood pressure is 130/84 mm Hg, and pulse is 86/min.  On examination, air conduction is greater than bone conduction in both ears.  When the base of a tuning fork is placed against her forehead, the sound is heard more prominently in the left ear.  Which of the following is the most likely cause of this patient's condition?

Accepted Answer

Explanation: 11ec25c8_d54c_7fc2_bc81_0d1487c38f03_MD0003_00 This patient with episodic vertigo, tinnitus, and sensorineural hearing loss (based on Weber and Rinne tuning fork tests) has Ménière disease, a disorder of the inner ear characterized by increased volume and/or pressure of endolymph (endolymphatic hydrops). The resulting distension of the endolymphatic system causes damage to both the vestibular and cochlear components of the inner ear. Ménière disease is characterized by the following triad: Weber and Rinne Episodic vertigo (20 min to 24 hr), commonly associated with nausea and vomiting Sensorineural hearing loss, fluctuating and varying in severity and usually worsening over time (primarily affecting low frequencies at first and progressing to permanent loss over all frequencies) Low-frequency tinnitus in the affected ear, often accompanied by a feeling of fullness The diagnosis of Ménière disease is based primarily on clinical findings; however, audiometry should be performed to fully characterize the hearing loss and follow its course over time, and MRI should be obtained to rule out central nervous system lesions. Initial management includes restriction of sodium, caffeine, nicotine, and alcohol. Benzodiazepines, antihistamines, and antiemetics can relieve acute symptoms. Diuretics can be considered. A minority of patients may require interventional techniques (eg, endolymphatic shunt placement) for severe, intractable vertigo. (Choice A) Vestibular schwannomas can cause unilateral sensorineural hearing loss, sometimes with imbalance and tinnitus. However, symptoms are usually persistent and progressive rather than episodic, and true vertigo is not typical. (Choice B) Multiple sclerosis can cause episodic vertigo and sensorineural hearing loss. However, most patients have manifestations in multiple systems (eg, paresthesias, weakness, visual disturbances, urinary incontinence). (Choice D) Like Ménière disease, labyrinthitis can cause vertigo, hearing loss, and tinnitus. However, symptoms typically last a few days to several weeks. (Choice E) Benign paroxysmal positional vertigo is thought to be caused by calcium debris within the semicircular canals that alter normal fluid flow. It causes brief (<1 min), often intense episodes of vertigo triggered by changes in head position. Patients can have headaches or a feeling of ear fullness, but tinnitus and hearing loss are not typical. Educational objective: Ménière disease is a disorder of the inner ear characterized by increased volume and/or pressure of endolymph (endolymphatic hydrops). Clinical features include episodic vertigo, sensorineural hearing loss, and tinnitus or aural fullness. References: Meniere's Disease (http://www.ncbi.nlm.nih.gov/pubmed/30947172)

Question 13

A 78-year-old woman is brought to the emergency department by her daughter, who is concerned about the patient's increasing forgetfulness and ability to live on her own.  The daughter says, "Over the past month, my mother seems to ask me the same questions over and over.  When I visited last week, she seemed slowed down overall and couldn't remember if she had taken a shower that day.  She has also stopped shopping for groceries and cooking for herself, although she did eat all the meals that I prepared."  The patient takes medications for type 2 diabetes mellitus, hypertension, and urinary incontinence.  Over the past several months, she has had difficulty sleeping due to a burning sensation in her feet from diabetic neuropathy.  After recently discussing these symptoms with her primary care physician, the patient was prescribed a new medication that provided significant relief.  Blood pressure is 138/86 mm Hg and pulse is 84/min and regular.  The lungs are clear on auscultation and heart sounds are normal.  The abdomen is soft and nontender.  The patient's gait is slow, but there are no focal neurologic deficits.  Montreal Cognitive Assessment score is 24/30 (normal: ≥26) with deficits in orientation, attention, and recall.  Which of the following is the most appropriate next step in management of this patient?

Accepted Answer

This elderly patient's acute onset of cognitive impairment after the recent addition of medication for diabetic neuropathy to an already complex drug regimen is consistent with a polypharmacy-related adverse effect. The elderly are especially vulnerable to the cumulative adverse cognitive effects of multiple drugs, which may produce cognitive impairment that can mimic dementia. Cumulative adverse effects may be further complicated by drug-drug interactions (eg, cytochrome P450 inhibitors), resulting in higher blood levels of impairing drugs. The most common medications associated with cognitive impairment in the elderly have anticholinergic properties; examples include oxybutynin for urinary incontinence and amitriptyline for diabetic neuropathy. Drugs without anticholinergic properties, especially sedating drugs (eg, benzodiazepines), may also contribute to the adverse effect burden of polypharmacy. This patient is taking more than one medication that may cause adverse effects in cognition. The tricyclic antidepressant amitriptyline is frequently used as a first-line agent for diabetic neuropathy and has strong anticholinergic properties. In addition, anticholinergic medications (eg, oxybutynin) are frequently used in the treatment of incontinence, potentially adding to the anticholinergic burden. Given this patient's high risk for polypharmacy-related adverse effects, her medication regimen should be reviewed prior to further diagnostic workup or treatment for dementia. Reducing or discontinuing the use of anticholinergic and sedating medications would be a priority in this patient. (Choice A) It would be premature to recommend placement in an assisted living facility without first evaluating the patient for reversible causes of cognitive decline. (Choice B) Donepezil, a cholinesterase inhibitor, is frequently used in treating dementia. However, adding this medication before determining the origin of this patient's cognitive impairment would be inappropriate and may further exacerbate issues related to polypharmacy. (Choices C and E) Screening for depression and hearing and vision loss may be considered part of the evaluation for apparent cognitive impairment but would not be the immediate next step in a patient with no reported mood changes or visual or hearing symptoms. (Choice D) This patient has no focal neurologic deficits. A dementia workup performed to rule out reversible causes of dementia, commonly includes an MRI of the brain and laboratory testing (eg, complete blood count, complete metabolic panel, TSH and vitamin B₁₂ levels) but would not precede a comprehensive medication review. dementia workup Educational objective: The elderly are especially vulnerable to the cumulative adverse effect burden of polypharmacy. In particular, medications with anticholinergic properties are strongly associated with the risk for cognitive impairment, which may produce a medication-induced syndrome that mimics dementia. Review of medications is an important first step in evaluating a patient on a complex medication regimen with new-onset or worsening cognitive impairment. References: The association between polypharmacy and dementia: a nested case-control study based on a 12-year longitudinal cohort database in South Korea. (http://www.ncbi.nlm.nih.gov/pubmed/28056068) Association between polypharmacy and dementia-a systematic review and meta-analysis. (http://www.ncbi.nlm.nih.gov/pubmed/29746153) Poly-de-prescribing to treat polypharmacy: efficacy and safety. (http://www.ncbi.nlm.nih.gov/pubmed/29318004) Long-term cognitive and functional effects of potentially inappropriate medications in older women. (http://www.ncbi.nlm.nih.gov/pubmed/24293516)

Question 14

A 55-year-old man comes to the office due to progressive difficulty walking and frequent falls over the past year.  Initially the patient had difficulty with balance when walking up and down the stairs.  Now he has to brace himself against a wall even when walking on flat surfaces.  He has had no urinary incontinence, slurred speech, or headaches.  The patient was diagnosed with type 2 diabetes mellitus and hypertension several years ago but is not compliant with medications.  He also has a history of long-term, heavy alcohol and tobacco use.  Blood pressure is 170/96 mm Hg and pulse is 84/min.  The patient is alert and oriented.  Bilateral pupils are equal and reactive.  Extraocular movements are normal.  Muscle bulk, tone, and strength are normal.  Proprioception and vibration sensation are normal in the lower extremities.  The patient exhibits a wide-based gait and is unable to perform tandem walking.  Heel-knee-shin testing is abnormal but finger-nose testing is normal.  Which of the following is the most likely cause of his ambulatory dysfunction?

Accepted Answer

11ec25c8_d554_47fa_bc81_8fd59c03fae4_MD0003_00 This patient with a long history of heavy alcohol use has slowly progressive postural gait dysfunction, suggestive of cerebellar degeneration due to alcohol neurotoxicity. Cerebellar degeneration typically occurs after >10 years of heavy alcohol use and is due to the degeneration of Purkinje cells in the cerebellar vermis. As these neurons are largely responsible for truncal coordination, patients with cerebellar degeneration usually develop slowly progressive wide-based gait and postural instability. Physical examination typically shows evidence of postural incoordination (eg, inability to tandem walk, abnormal heel-knee-shin testing) with relatively preserved limb coordination (normal finger-nose testing). Cognitive function is usually preserved. Although alcohol cessation and nutritional supplementation prevent disease progression, ambulatory difficulties do not typically improve. Patients therefore usually benefit from ambulatory assist devices such as canes or walkers. (Choice B) Impaired absorption of cerebrospinal fluid is seen with normal-pressure hydrocephalus. Manifestations include progressive imbalance, cognitive decline, and urinary incontinence. This patient has normal cognition and no urinary incontinence. (Choice C) Spondylotic myelopathy is associated with osteophyte-mediated spinal cord compression. Manifestations include gait dysfunction, extremity weakness, vibratory/proprioception abnormalities, and both lower and upper motor neuron findings. This patient has no lower motor neuron findings (eg, muscle atrophy, weakness) and no loss of vibration/proprioception. (Choice D) Diabetes mellitus may cause small vessel injury with resultant peripheral nerve ischemia. Patients typically manifest a distal symmetric polyneuropathy of both small fibers (pain/temperature) and large fibers (vibration/proprioception). Gait is usually preserved. (Choice E) Wernicke encephalopathy is characterized by thiamine deficiency-induced thalamic neuronal loss and usually causes gait ataxia, oculomotor dysfunction (eg, horizontal nystagmus), and encephalopathy. This patient's cognition and oculomotor function is unaffected. (Choice F) Vascular dementia is caused by multiple small infarctions. Manifestations typically develop in a stepwise fashion over years and include cognitive changes; a short, shuffling gait; and postural instability. (Choice G) Vitamin B₁₂ deficiency may cause spinal cord degeneration. Early manifestations include ataxia, symmetric paresthesia, and a loss of vibration and proprioception sensation. This patient's vibration and proprioception are normal. Educational objective: Alcoholic cerebellar degeneration is caused by damage to the Purkinje cells of the cerebellar vermis. Manifestations typically include the slowly progressive onset of ambulation difficulties, including wide-based gait and postural instability. Truncal coordination (eg, tandem gait) is impaired, but limb coordination (eg, finger-nose test) is relatively intact. References: Population-based study of alcoholic cerebellar degeneration: the Atahualpa Project. (http://www.ncbi.nlm.nih.gov/pubmed/27423619) Early-stage alcoholic cerebellar degeneration: diagnostic imaging clues. (http://www.ncbi.nlm.nih.gov/pubmed/26848494) Effects of ethanol on the cerebellum: advances and prospects. (http://www.ncbi.nlm.nih.gov/pubmed/25933648)

Question 15

A 69-year-old woman is brought to the office by her husband due to forgetfulness.  The patient is a retired law professor who taught classes until a year ago when she began to have difficulty remembering lesson plans.  Since then, her memory has worsened, and she has gotten lost during her normal neighborhood walk on more than one occasion.  Her husband has taken over responsibility for all cooking and cleaning; moreover, the patient is unable to drive or use public transportation on her own.  Medical history is significant for hypertension and type 2 diabetes mellitus for which she takes lisinopril and metformin.  The patient has no family history of memory problems.  Temperature is 36.7 C (98.1 F), blood pressure is 134/74 mm Hg, pulse is 72/min, and respirations are 14/min.  She scores a 22/30 on Montreal Cognitive Assessment (normal: ≥26).  There are no focal neurologic deficits.  Which of the following is the most appropriate next step in evaluation of this patient?

Accepted Answer

11ec25c8_d546_8c4b_bc81_edeab9cf056f_MD0003_00 This patient's year-long history of progressive cognitive decline and associated impairment in activities of daily living (eg, cooking, cleaning, using transportation) meets criteria for dementia (also known as major neurocognitive disorder). Her prominent memory symptoms, insidious disease course, and lack of associated neurological findings make Alzheimer disease (AD) more likely than other subtypes of dementia (eg, vascular dementia, frontotemporal dementia, dementia with Lewy bodies). AD, the most common form of dementia in older patients, is inevitably progressive and irreversible. However, before a definitive diagnosis is made, all patients should undergo a workup for potentially reversible causes of cognitive impairment. No matter which subtype is suspected, the initial evaluation of suspected dementia is similar. Evaluation involves neuropsychological testing (eg, Montreal Cognitive Assessment), laboratory testing (complete blood count, vitamin B₁₂, TSH, complete metabolic panel), and neuroimaging. The apolipoprotein E epsilon 4 allele is associated with an increased risk for AD. However, genetic testing is contraindicated for the routine evaluation of suspected dementia because it exposes patients to the potential psychological harms of false positives and false negatives without providing sufficient clinical utility. (Choices A and B) Cerebrospinal fluid testing and electroencephalogram are only indicated in patients with specific risk factors. Cerebrospinal fluid testing may be indicated when a suspected underlying infection or malignancy is believed to be contributing to the presentation. Electroencephalogram may be considered in patients with an underlying seizure disorder or in those exhibiting seizure like activity. (Choices C and F) Folate and vitamin D levels are not routinely obtained; they are indicated only in specific risk groups. For example, patients with alcohol use disorder may have folate deficiencies that can contribute to cognitive impairment. Some conditions may place a patient at risk for vitamin D deficiency (eg, celiac disease, chronic kidney disease) and may also justify targeted testing. (Choice D) Syphilis testing is indicated only in patients with specific risk factors such as those with a known exposure. Educational objective: The initial workup of suspected dementia should include neuropsychological testing (eg, Montreal Cognitive Assessment), selected laboratory testing (complete blood count, complete metabolic panel, TSH, vitamin B₁₂), and neuroimaging (eg, MRI). Patients in specific risk groups may warrant additional targeted testing. References: Dementia for the primary care provider. (http://www.ncbi.nlm.nih.gov/pubmed/28797371) Evaluation of suspected dementia. (http://www.ncbi.nlm.nih.gov/pubmed/22010769)

Question 16

A 60-year-old man comes to the office due to right-sided neck and shoulder pain.  The pain worsens with neck movement and is associated with numbness in his forearm.  Over the past 2 years, he has had several episodes of similar symptoms that improved with rest and ibuprofen.  The patient has no history of neck or shoulder trauma.  He smokes a pack of cigarettes daily and has used injection drugs in the past.  Vital signs are within normal limits.  Physical examination shows limited neck rotation and lateral bending.  There is decreased pinprick sensation on the posterior aspect of the right forearm but no muscle weakness.  Triceps reflex is normal.  Left upper and bilateral lower extremity examination show no other abnormalities.  A plain radiograph of the cervical spine is ordered.  This patient's symptoms are most likely associated with which of the following radiographic findings?

Accepted Answer

11ec25c8_d555_0b4b_bc81_a5817d6a4bdc_MD0003_00 This patient's episodic neck/shoulder pain, reduced neck mobility, and sensory changes in his forearm raise suspicion for cervical radiculopathy. Most cases arise in older adults due to acute cervical disc herniation or underlying cervical spondylosis. Cervical spondylosis is a degenerative condition of the spine marked by osteophyte formation in the facet and uncovertebral joints, which leads to neural foramina narrowing. Although many cases are asymptomatic, some patients develop nerve root compression (radiculopathy) with neck/shoulder pain and upper extremity sensory, motor, and/or reflex abnormalities in a dermatomal distribution. In patients with spondylosis, sclerotic facet joints with osteophytes can be seen on cervical spine films, but MRI is often obtained in those who have motor or reflex abnormalities as it better visualizes the spine and surrounding soft tissues. (Choice A) Atlantoaxial subluxation can occur in patients with rheumatoid arthritis, leading to compressive cervical myelopathy. Manifestations generally begin with neck pain that radiates to the occiput, but patients frequently develop progressive spastic paresis, Lhermitte sign (shock like sensation down the spine), and lower extremity manifestations. Episodic neck/shoulder pain and forearm paresthesia would be atypical. (Choice B) Thoracic and lumbar compression fractures usually occur in the setting of underlying osteoporosis; they typically manifest with focal spinal pain/tenderness, not radiculopathy. Cervical compression fractures are uncommon and usually occur in the setting of high-impact trauma. (Choice D) Spinal metastasis or osteomyelitis can cause focal osteolytic lesions; these conditions generally cause local spine pain/tenderness. Neither is likely to cause episodes of neck/shoulder pain over 2 years. (Choice E) Odontoid process fracture usually occurs in the setting of high-impact trauma (eg, motor vehicle collision) and generally results in spinal cord compression (myelopathy), not radiculopathy. (Choice F) Vertebral body squaring is an early sign of ankylosing spondylitis, an inflammatory condition of the spine that generally presents with chronic, progressive neck/back pain in a patient age <40. Radiculopathy would be atypical; most patients have pain that is worse at night and improves with activity. Educational objective: Cervical radiculopathy often arises in older individuals due to underlying cervical spondylosis. Manifestations generally include neck pain that radiates to the shoulder/arm and unilateral upper extremity sensory, motor, and/or reflex abnormalities in a dermatomal distribution. Spine imaging generally shows abnormal facet joints, including the presence of sclerosis and osteophytes.

Question 17

A 75-year-old man is brought to the emergency department with severe back pain that began 3 weeks ago.  The pain has been significantly worse for the last 12 hours.  This morning, the patient also noticed difficulty walking and urinating.  He has a history of advanced prostate cancer initially treated with local radiation therapy.  Temperature is 37 C (98.6 F), blood pressure is 122/83 mm Hg, and pulse is 104/min.  The patient appears uncomfortable.  He has point tenderness over the midline spine near T10 and T11.  Upper extremity strength and reflexes are normal.  Muscle strength in the lower extremities is 3/5 and deep-tendon reflexes are 3+ bilaterally.  Bilateral plantar reflexes are upgoing.  Straight urinary catheterization produces 800 mL of urine.  Which of the following is the best initial step in management of this patient?

Accepted Answer

11ec25c8_d54d_9134_bc81_0df3c429e2de_MD0003_00 This patient with advanced prostate cancer presents with subacute back pain that has now profoundly changed in severity. Examination shows lower extremity motor weakness, hyperreflexia, and bladder dysfunction, raising concern for epidural spinal cord compression (ESCC). The thoracic (60%) and lumbosacral (30%) spine are the most common locations for ESCC. Cancers that often metastasize to the spine include lung, breast, and prostate, as well as multiple myeloma. Early diagnosis of ESCC is crucial in preserving neurologic function; in fact, the primary determinant of outcome is the degree of neurologic involvement at the time of intervention. Pain is typically the first symptom, often present for 1-2 months before additional symptoms appear. Motor findings (bilateral weakness) and ataxia are common as the disease progresses. Bowel and bladder dysfunction are late findings. Although imaging (MRI) plays an important role in the diagnosis of ESCC, intravenous glucocorticoids should be given without delay in a patient with suspected neoplastic ESCC. Glucocorticoids decrease vasogenic edema (caused by obstructed epidural venous plexus), help alleviate pain, and may restore neurologic function. Once imaging confirms ESCC, neurosurgery and/or radiation oncology consultation is typically required. (Choice A) Analgesics and baclofen are used for muscular spasm. Alpha blockers may help relieve bladder obstruction from an enlarged prostate. This patient is manifesting signs of significant bilateral motor nerve involvement, making a muscular cause much less likely than a critical neurologic cause. (Choice C) Radiation to the spine is a useful intervention for painful spinal metastases. It may play a role in this patient's treatment but requires imaging and scheduling. Glucocorticoids should not be delayed. (Choices D and E) A radionuclide bone scan and skeletal survey (x-rays of major bones) can detect metastatic bone disease but do not provide useful information about compression of the thecal sac; therefore, they are not recommended for diagnosis of ESCC. In general, glucocorticoids should not be delayed for imaging in this patient as the pretest probability of ESCC is quite high (given patient's neurologic findings, history of prostate cancer, and symptoms). Educational objective: Epidural spinal cord compression must be suspected in any patient with a history of malignancy who develops back pain with motor and sensory abnormalities. Bowel and bladder dysfunction are late neurologic findings. Intravenous glucocorticoids should be given without delay. MRI is then recommended. References: Spinal cord compression. (http://www.ncbi.nlm.nih.gov/pubmed/22547256)

Question 18

A 32-year-old woman comes to the office for a regularly scheduled follow-up visit.  She has mild fatigue but no other symptoms.  Medical history is significant for generalized seizures controlled with chronic phenytoin therapy.  Her last seizure was 6 months ago.  She does not use tobacco, alcohol, or illicit drugs.  She is afebrile and vital signs are within normal limits.  Examination shows mild gingival hyperplasia and pallor.  There is no jaundice or lymphadenopathy.  Cardiopulmonary examination is normal.  The abdomen is soft and nontender with no hepatosplenomegaly.  Laboratory results are as follows:  Supplementation with which of the following could have prevented this patient's condition?

Accepted Answer

Explanation: This patient with a history of seizure disorder is being treated with phenytoin, an antiepileptic with several common adverse effects, including: Folic acid deficiency: Phenytoin impairs folic acid absorption in the jejunum, which often results in folic acid deficiency over weeks or months. Because folate (tetrahydrofolate) is required for purine and thymidine synthesis, deficiency impairs DNA synthesis, particularly in cells that undergo rapid turnover (eg, hematologic cells). This often leads to megaloblastic anemia (eg, macrocytosis, hypersegmented neutrophils). Gingival overgrowth/hyperplasia: Phenytoin has several effects on the gingival mucosa but is thought to reduce folic acid use in the extracellular matrix of the gums, leading to impaired collagenase activity and a subsequent buildup of gingival matrix. These adverse effects can usually be prevented with oral folic acid supplementation. Because phenytoin also disrupts bone and mineral metabolism (leading to reduced bone density), calcium and vitamin D supplementation are also generally administered. Other medications that commonly cause megaloblastic anemia include methotrexate, trimethoprim, and pyrimethamine due to disruptions in dihydrofolate reductase (the enzyme that mediates tetrahydrofolate production). (Choice B) Iron deficiency causes microcytic anemia and does not enhance gingival growth. (Choice C) Vitamin B₁ (thiamine) deficiency can occur in those who use excess alcohol; it causes Wernicke encephalopathy, which is characterized by gait dysfunction, confusion, and oculomotor palsy. Macrocytic anemia is atypical. ₁ (Choice D) Vitamin B₆ (pyridoxine) deficiency is associated with peripheral neuropathy, not macrocytic anemia. Pyridoxine deficiency often occurs as a consequence of isoniazid therapy for tuberculosis; high risk patients are given pyridoxine supplementation to prevent this adverse effect. ₆ (Choice E) Vitamin B₁₂ deficiency also causes megaloblastic anemia but is not associated with gingival hyperplasia or phenytoin use. ₁₂ Educational objective: Phenytoin commonly causes megaloblastic anemia and gingival hyperplasia due to impaired folic acid absorption in the jejunum. Supplementation with folic acid prevents these adverse effects. Calcium and vitamin D supplementation are also usually given to counter alterations in bone mineral metabolism that impair bone density.

Question 19

A 62-year-old woman comes to the office due to progressive gait unsteadiness.  The patient's legs feel stiff, and she frequently stumbles and has to hold handrails while descending stairs.  She also has had tingling and numbness in the hands and an occasional electric shock-like sensation in the spine.  She has had no bowel or bladder incontinence.  The patient has fibromyalgia and continues to have shoulder and neck pain despite a recent dosage increase in duloxetine.  Other medical conditions include depression and hypothyroidism.  She does not use tobacco, alcohol, or illicit drugs.  Examination of the cranial nerves is normal.  Upper extremity muscle strength is decreased, with mild wasting of intrinsic hand muscles.  Lower extremity tone and reflexes are increased bilaterally.  Sensation is grossly intact.  Which of the following is the most likely cause of this patient's current condition?

Accepted Answer

Explanation: This patient's gait unsteadiness, shock sensation in the spine, atrophy/weakness in the upper extremities, and increased tone/reflexes in the lower extremities raise suspicion for spinal cord compression (myelopathy) in the cervical spine. Myelopathy is most common in older adults who have cervical spondylosis, a degenerative condition associated with spinal canal narrowing due to the formation of osteophytes in the lateral vertebral bodies and ossification of the posterior longitudinal ligament/ligamentum flavum. In approximately 15% of patients, canal narrowing causes mechanical spinal cord compression and interruption of blood supply to the cord, resulting in cervical spondylotic myelopathy. Manifestations include insidious, progressive neurologic deficits in the upper and lower extremities due to: Damage to the cervical spine nerve roots (peripheral nervous system), which leads to neck pain that radiates to the shoulders/arms and lower motor neuron findings (eg, weakness, atrophy, reduced reflexes) in a myotome/dermatome distribution in the upper extremities Damage to the spinal cord descending tracts (central nervous system), which leads to unsteady gait (spastic, scissoring walk), a sensation of leg weakness/stiffness, and upper motor neuron signs (eg, increased reflexes, increased tone, upgoing Babinski sign) in the lower extremities An electric shock-like sensation down the spine with forward flexion of the neck (Lhermitte sign) is also commonly seen. MRI scan of the cervical spine is the first test of choice, but myelography is often required. Surgical decompression is sometimes necessary for those with moderate/severe symptoms or progressive neurologic dysfunction. (Choice A) Amyotrophic lateral sclerosis is a demyelinating polyneuropathy that typically causes both upper and lower motor neuron signs. However, most patients present with asymmetric (not symmetric) limb weakness and atrophy; in addition, Lhermitte sign is atypical, and cervical spondylotic myelopathy is far more common. (Choice B) Lumbar spinal stenosis is associated with low back pain and sensory loss/weakness in the lower extremities exacerbated by prolonged walking/standing and alleviated by sitting/lying (pseudoclaudication). Upper motor neuron signs are absent, and the upper extremities are unaffected. (Choice C) Spinal cord inflammation from multiple sclerosis can cause Lhermitte sign and upper motor neuron findings; however, lower motor neuron symptoms are absent because the disease does not affect the peripheral nervous system. In addition, most cases arise in young adults. (Choice D) Polymyositis is an inflammatory myopathy associated with symmetric, proximal skeletal muscle weakness. Spasticity and increased reflexes would not be seen. Educational objective: Cervical spondylotic myelopathy is common in older adults and generally presents with progressive neck pain, gait disturbances, lower motor neuron signs in the upper extremities (eg, weakness, diminished reflexes), and upper motor neuron signs in the lower extremities (eg, increased reflexes, spasticity).

Question 20

A 40-year-old woman comes to the office due to daily headaches and facial pain for the past several months.  The pain involves the temporal and periorbital region, affects the right side more than the left, is dull, and waxes and wanes.  It is often worse toward the end of the day, and the patient gets a heavy and tired feeling in her jaws while eating dinner.  Current medications are a multivitamin daily and ibuprofen as needed.  She is a research professor and describes her work as stressful.  The patient does not use tobacco, alcohol, or illicit drugs.  Vital signs are within normal limits.  Physical examination shows normal pupils and no facial droop.  Facial sensation is normal bilaterally and there is mild tenderness in the right masseter muscle.  The remainder of the examination shows no abnormalities.  Which of the following is the most likely diagnosis?

Accepted Answer

11ec25c8_d54b_4740_bc81_2d1859ddbfd7_MD0003_00 This patient with headaches, facial pain, an achy jaw, and masseter muscle tenderness likely has temporomandibular joint disorder (TMD). The most recognizable findings are pain exacerbated by jaw motion, tenderness of the temporomandibular joint, and neck symptoms. However, TMD can also present primarily with headaches, muscle spasms, and jaw fatigue, as in this patient. Patients with anxiety may be at increased risk. The diagnosis of TMD is typically clinical. Palpation of the temporomandibular joint during jaw opening and closing often elicits pain, crepitus, and/or audible clicks. Tenderness of the muscles of mastication (eg, masseter, temporalis) is often present. Initial management of TMD should consist of education, a soft diet, warm compresses, and avoidance of triggers. Nonsteroidal anti-inflammatory drugs are the first-line medication. Muscle relaxants (eg, cyclobenzaprine) can be added for patients with associated muscle spasm. (Choice A) Fibromyalgia can cause pain and muscle tenderness in young or middle-aged women. However, pain is typically widespread, and physical examination shows tenderness at specific trigger points (eg, midtrapezius, lateral epicondyle). (Choice B) Giant cell arteritis can present with headaches and jaw pain when chewing (ie, jaw claudication). However, it very rarely occurs in patients age <50. (Choice C) Myasthenia gravis can present with fluctuating, fatigable bulbar muscle weakness (eg, dysarthria, dysphagia) that is worse at the end of the day. However, pain and focal muscle tenderness are uncommon. (Choice E) Tension headaches can present with pressure and muscle tenderness in the head and neck, especially during times of stress. However, the headaches are symmetric and do not typically cause focal (eg, masseter muscle) tenderness or jaw heaviness. (Choice F) Trigeminal neuralgia can present with unilateral facial pain. However, the pain is typically recurrent, severe, and shocklike rather than dull, heavy, and waxing and waning. Educational objective: Temporomandibular joint disorder can present with headaches, muscle spasms, jaw fatigue, and facial pain. Physical examination can reveal tenderness of the muscles of mastication, as well as pain, crepitus, and/or audible clicks from the joint. References: Diagnosis and treatment of temporomandibular disorders. (http://www.ncbi.nlm.nih.gov/pubmed/25822556)

Exam 1: Medicine