Neuro 3 - Answers PDF
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Miller School of Medicine, University of Miami
National Board of Medical Examiners
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This is a past paper from the National Board of Medical Examiners, covering clinical neurology self-assessment. The paper contains questions and answers regarding neurology, including cases studies and diagnoses. The exam is for postgraduate level.
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Exam Section: Item 1 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 1. A 25-year-old woman comes to the physician because of...
Exam Section: Item 1 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 1. A 25-year-old woman comes to the physician because of growths on her lips and tongue for several years. Examination shows nodules on the lips, buccal mucosa, and tongue; cafe au lait spots over the trunk and limbs; and scattered nodules on the skin. This patient is at greatest risk for which of the following conditions? A) Craniopharyngioma B) Ependymoma C) Lym phoma D) Optic nerve glioma E) Pituitary adenoma Correct Answer: D. Mucosa! neuromas, growths on the oral mucosa and lips, are a finding of multiple endocrine neoplasia (MEN) type 2B. Other features of MEN2B include medul lary thyroid carcinoma, and pheochromocytoma. MEN2B is also associated with neurofibromatosis type I, and these disorders can present simultaneously. Neurofibromatosis type I (von Recklinghausen disease) is a genetically inherited disorder caused by a defect in NF1, the gene which encodes neurofibromin on chromosome 17. It follows an autosomal dominant pattern of inheritance. It is characterized by a constellation of cutaneous manifestations (neurofibromas, plexiform neurofibromas, cafe au lait macu les, and axillary freckling), a variety of central nervous system tumors including optic nerve glioma and iris hamartoma (Lisch nodule), and bony abnormalities such as long bone dysplasia and sphenoid wing dysplasia. Patients are also at higher risk for developing astrocytomas, brainstem gliomas, and soft tissue sarcomas. Neurofibromatosis type II has a different constellation of findings: bilateral acoustic schwannomas, cataracts, meningiomas, and ependymomas, and is not associated with MEN. Incorrect Answers: A, B, C, and E. While several intracranial neoplasms are associated with neurofibromatosis type I, neither craniopharyngioma (Choice A) nor pituitary adenoma (Choice E) are among them. Ependymoma (Choice B) is a central nervous system neoplasm formed from ependymal cel ls which typical ly arises in the fourth ventricle. Ependymoma is a feature of neurofibromatosis type II. Lymphoma (Choice C) is a hematologic malignancy derived from lymphocytes which has many different subtypes and presentations. CNS lymphoma is a type of intracranial neoplasm, but it is not seen in neurofibromatosis type I or MEN2B. Educational Objective: MEN2B demonstrates mucosa! neuromas, medullary thyroid carcinoma, and pheochromocytoma, and is associated with neurofibromatosis type I. The constellation of findings in neurofibromatosis type I include neurofibromas, plexiform.... -- - - - -- - - - - - - - -- - - -- - - -- - - - - - - - - - - -- - - - - -- - - - -- - --- --- - --- ---- - -- -- - --- ~, https://t.me/USMLENBME2CK - ~ ~ r, Next Score Report Lab Values Calculator Help Pause Exam Section: Item 1 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment... A) Craniopharyngioma B) Ependymoma C) Lymphoma D) Optic nerve glioma E) Pituitary adenoma Correct Answer: D. Mucosal neuromas, growths on the oral mucosa and lips, are a finding of multiple endocrine neoplasia (MEN) type 2B. Other features of MEN2B include medul lary thyroid carcinoma, and pheochromocytoma. MEN2B is also associated with neurofibromatosis type I, and these disorders can present simultaneously. Neurofibromatosis type I (von Recklinghausen disease) is a genetically inherited disorder caused by a defect in NF1, the gene which encodes neurofibromin on chromosome 17. It follows an autosomal dominant pattern of inheritance. It is characterized by a constellation of cutaneous manifestations (neurofibromas, plexiform neurofibromas, cafe au lait macu les, and axillary freckling), a variety of central nervous system tumors including optic nerve glioma and iris hamartoma (Lisch nodule), and bony abnormalities such as long bone dysplasia and sphenoid wing dysplasia. Patients are also at higher risk for developing astrocytomas, brainstem gliomas, and soft tissue sarcomas. Neurofibromatosis type II has a different constellation of findings: bilateral acoustic schwannomas, cataracts, meningiomas, and ependymomas, and is not associated with MEN. Incorrect Answers: A, B, C, and E. While several intracranial neoplasms are associated with neurofibromatosis type I, neither craniopharyngioma (Choice A) nor pituitary adenoma (Choice E) are among them. Ependymoma (Choice B) is a central nervous system neoplasm formed from ependymal cel ls which typical ly arises in the fourth ventricle. Ependymoma is a feature of neurofibromatosis type II. Lymphoma (Choice C) is a hematologic malignancy derived from lymphocytes which has many different subtypes and presentations. CNS lymphoma is a type of intracranial neoplasm, but it is not seen in neurofibromatosis type I or MEN2B. Educational Objective: MEN2B demonstrates mucosal neuromas, medullary thyroid carcinoma, and pheochromocytoma, and is associated with neurofibromatosis type I. The constellation of findings in neurofibromatosis type I include neurofibromas, plexiform neurofibromas, cafe au lait macu les, axil lary freckling, optic nerve glioma, iris hamartoma (Lisch nodule), long bone dysplasia, and sphenoid wing dysplasia..,. ~, https://t.me/USMLENBME2CK ~ ~ r, Next Score Report Lab Values Calculator Help Pause Exam Section: Item 2 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 2. A 57-year-old woman comes to the physician because of a 3-month history of gradually progressive weakness in the shoulder and hip muscles. She has hypothyroidism treated with thyroxine but is otherwise healthy. Her vital signs are within normal limits. Neurologic examination shows moderate bilateral weakness of the deltoid, biceps, triceps, psoas, glutei , and quadriceps muscles. The remainder of the examination shows no abnormalities. Her erythrocyte sedimentation rate is 85 mm/h, and serum creatine kinase activity is 2456 U/L. Complete blood count and uri nalysis are within normal limits. Which of the following is the most appropriate next step in diagnosis? A) Quantitative sensory testing B) Electromyography and nerve conduction studies C) MRI of the spinal cord D) Skin biopsy E) Lumbar puncture Correct Answer: B. Electromyography and nerve conduction studies are used to support a diagnosis of inflammatory myopathy such as polymyositis, as in this case. Polymyositis is an autoimmune condition affecting the proximal muscles. It is closely related to dermatomyositis, however, unlike dermatomyositis, it does not present with cutaneous findings. The muscular inflammation is characterized by endomysial COB+ inflammatory infiltrate. This is in contrast to dermatomyositis which demonstrates a perimysial CD4+ inflammatory infiltrate. An inflammatory infiltrate of the muscle occurs, causing damage to the myocytes, leading to release of creatine kinase, an intracellular molecule. Erythrocyte sedimentation rate is also increased, indicating the presence of inflammation. This can be used to monitor disease progress in polymyositis. Both polymyositis and dermatomyositis are characterized by several autoantibodies: positive antinuclear antibody (ANA) and anti-Jo-1, anti-SRP, and anti-Mi-2. Treatment of polymyositis involves systemic steroids followed by long-term immunosuppressive therapy with medications such as methotrexate or azathioprine. Incorrect Answers: A, C, D, and E. Quantitative sensory testing (Choice A) is used to evaluate damage to small and large nerve endings, not primary muscle inflammation. MRI of the spinal cord (Choice C) would be beneficial in evaluating muscle weakness because of a spinal epidural abscess or tumor. While these pathologies can cause proximal muscle weakness, other symptoms such as feve r, back pain, and sensory deficits would also be seen. As polymyositis is an inflammatory myopathy with no spinal cord involvement, imaging of the spinal cord will not be helpful. Skin biopsy (Choice D) is indicated in evaluation of suspected dermatomyositis. However, this patient does not demonstrate any cutaneous findings, and thus, a skin biopsy is not warranted..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 2 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment... C) MRI of the spinal cord D) Skin biopsy E) Lumbar puncture Correct Answer: B. Electromyography and nerve conduction studies are used to support a diagnosis of inflammatory myopathy such as polymyositis, as in this case. Polymyositis is an autoimmune condition affecting the proximal muscles. It is closely related to dermatomyositis, however, unlike dermatomyositis, it does not present with cutaneous findings. The muscu lar inflammation is characterized by endomysial CD8+ inflammatory infiltrate. This is in contrast to dermatomyositis which demonstrates a perimysial CD4+ inflammatory infiltrate. An inflammatory infiltrate of the muscle occurs, causing damage to the myocytes, leading to release of creatine kinase, an intracellular molecule. Erythrocyte sedimentation rate is also increased, indicating the presence of inflammation. This can be used to monitor disease progress in polymyositis. Both polymyositis and dermatomyositis are characterized by several autoantibodies: positive antinuclear antibody (ANA) and anti-Jo-1, anti-SRP, and anti-Mi-2. Treatment of polymyositis involves systemic steroids followed by long-term immunosuppressive therapy with medications such as methotrexate or azathioprine. Incorrect Answers: A, C, D, and E. Quantitative sensory testing (Choice A) is used to evaluate damage to small and large nerve endings, not primary muscle inflammation. MRI of the spinal cord (Choice C) would be beneficial in evaluating muscle weakness because of a spinal epidural abscess or tumor. While these pathologies can cause proximal muscle weakness, other symptoms such as fever, back pain, and sensory deficits would also be seen. As polymyositis is an inflammatory myopathy with no spinal cord involvement, imaging of the spinal cord will not be helpful. Skin biopsy (Choice D) is indicated in evaluation of suspected dermatomyositis. However, this patient does not demonstrate any cutaneous findings, and thus, a skin biopsy is not warranted. Lumbar puncture (Choice E) may be used to diagnose Guillain-Barre syndrome, a demyelinating polyneuropathy that starts with the distal extremities and progresses proximally. It may affect the lungs through diaphragmatic paralysis, which is the most serious complication of the disease. Whi le proximal muscle weakness can ensue, this would only occur after involvement of the distal extremities. Educational Objective: Polymyositis and dermatomyositis are autoimmune inflammatory myopathies. Electromyography and nerve conduction studies are part of the initial evaluation of these diseases..,. r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 3 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 3. A 27-year-old man is brought to the emergency department because of multiple trauma sustained in a motor vehicle collision. He is initially arousable, but he is increasingly unresponsive over the next 45 minutes. The pupil of the left eye is dilated, and there is ptosis of the left eyelid. He begins to hyperventi late. Which of the following is the most likely cause? A) Alcohol withdrawal G) HIV encephalopathy B) Aseptic meningitis H) Infratentorial lesion C) Bacterial meningitis I) Myxedema D) Carbon monoxide poisoning J) Salicylate intoxication E) Central herniation K) Uncal herniation F) Factitious disorder L) Viral meningitis Correct Answer: K. After blunt head injury, patients can present with concussion or traumatic intracranial hemorrhage such as subdu ral hematoma, subarachnoid hemorrhage, or epidural hematoma. A young patient with initial normal mental status that then becomes altered or unresponsive raises suspicion for an epidural hematoma. Epidural hematoma is classically associated with trauma to the middle meningeal artery and can present with an initial lucid interval followed by deterioration of mental status caused by arterial bleeding and hematoma expansion. Over time , patients can have symptoms of headache, vomiting , confusion, seizures, and coma. Epidural hematomas present on CT as lens-shaped, biconvex hyperdense collections abutting the skull. They often compress adjacent brain and are bound by dural sutures. Epidural hematoma can be complicated by increased intracranial pressure, midline shift, uncal herniation, and death. Uncal herniation involves the uncus compressing the midbrain, typically affecting the oculomotor nerve (cranial nerve Ill), causing pupillary dilation, ptosis, and oculomotor nerve palsy. Emergent craniotomy and decompression of the epidural hematoma is often necessary. Incorrect Answers: A, B, C, D, E, F, G, H, I, J, and L. Alcohol withdrawal (Choice A) presents with tremulousness, nausea, vomiting, anxiety, and tongue fasciculations. Delirium tremens is a life-threatening complication of alcohol withdrawal that presents with severe confusion, agitation, visual hallucinations, and autonomic instability. Aseptic meningitis (Choice B), bacterial meningitis (Choice C), and viral meningitis (Choice L) typically present with fever, headache, and nuchal rigidity. This patient has no signs of meningitis and his altered mental status is more likely because of blunt head trauma. Carbon monoxide (CO) poisoning (Choice D) occurs as a consequence of inhaling the gas. CO has an affinity for hemoglobin that is hundreds of times greater than that of oxygen, readily displacing oxygen from heme. Symptoms of CO poisoning include headache, loss of consciousness, dizziness, vomiting, and fatigue..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 3 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment... Correct Answer: K. After blunt head injury, patients can present with concussion or traumatic intracranial hemorrhage such as subdural hematoma, subarachnoid hemorrhage, or epidural hematoma. A young patient with initial normal mental status that then becomes altered or unresponsive raises suspicion for an epidural hematoma. Epidural hematoma is classically associated with trauma to the middle meningeal artery and can present with an initial lucid interval followed by deterioration of mental status caused by arterial bleeding and hematoma expansion. Over time, patients can have symptoms of headache, vomiting, confusion, seizures, and coma. Epidural hematomas present on CT as lens-shaped, biconvex hyperdense collections abutting the skull. They often compress adjacent brain and are bound by dural sutures. Epidural hematoma can be complicated by increased intracranial pressure, mid line shift, uncal herniation, and death. Uncal herniation involves the uncus compressing the midbrain, typical ly affecting the oculomotor nerve (cranial nerve Ill), causing pupi llary dilation, ptosis, and oculomotor nerve palsy. Emergent craniotomy and decompression of the epidural hematoma is often necessary. Incorrect Answers: A, B, C, D, E, F, G, H, I, J, and L. Alcohol withdrawal (Choice A) presents with tremulousness, nausea, vomiting, anxiety, and tongue fasciculations. Delirium tremens is a life-threatening complication of alcohol withdrawal that presents with severe confusion, agitation, visual hallucinations, and autonomic instability. Aseptic meningitis (Choice B), bacterial meningitis (Choice C), and viral meningitis (Choice L) typically present with fever, headache, and nuchal rigidity. This patient has no signs of meningitis and his altered mental status is more likely because of blunt head trauma. Carbon monoxide (CO) poisoning (Choice D) occurs as a consequence of inhaling the gas. CO has an affinity for hemoglobin that is hundreds of times greater than that of oxygen, readily displacing oxygen from heme. Symptoms of CO poisoning include headache, loss of consciousness, dizziness, vomiting, and fatigue. Central herniation (Choice E) typical ly presents with decreased responsiiveness, posturing, and fixed pupils. The patient has signs of uncal herniation and oculomotor nerve compression leading to unilateral pupi llary dilation and ptosis. Factitious disorder (Choice F) refers to a psychiatric disorder in which patients falsely present themselves or others as ill or injured. HIV encephalopathy (Choice G) can cause chronic neurocognitive impaiirment and behavioral changes. It would be unlikely in this patient with acute altered mental status. lnfratentorial lesions (Choice H) are associated with mu ltiple sclerosis or tumors in children. Multiple sclerosis is an autoimmune demyelinating disease that presents with focal neurologic deficits separated in space and time. Myxedema (Choice I) refers to a severe hypothyroid state, and presents with edema, lethargy, hypotension, and electrolyte disturbances, not with acute-onset hyperventilation and loss of consciousness following trauma..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 3 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment Please Walt (cranial nerve Ill), causing pupi llary dilation, ptosis, and oculomotor nerve palsy. Emergent craniotomy and decompression of the epidural hematoma is... often necessary. Incorrect Answers: A, B, C, D, E, F, G, H, I, J, and L. Alcohol withdrawal (Choice A) presents with tremulousness, nausea, vomiting, anxiety, and tongue fasciculations. Delirium tremens is a life-threatening complication of alcohol withdrawal that presents with severe confusion, agitation, visual hallucinations, and autonomic instabi lity. Aseptic meningitis (Choice B), bacterial meningitis (Choice C), and viral meningitis (Choice L) typically present with fever, headache, and nuchal rigidity. This patient has no signs of meningitis and his altered mental status is more likely because of blunt head trauma. Carbon monoxide (CO) poisoning (Choice D) occurs as a consequence of inhaling the gas. CO has an affinity for hemoglobin that is hundreds of times greater than that of oxygen, readily displacing oxygen from heme. Symptoms of CO poisoning include headache, loss of consciousness, dizziness, vomiting, and fatigue. Central herniation (Choice E) typical ly presents with decreased responsiiveness, posturing, and fixed pupils. The patient has signs of uncal herniation and oculomotor nerve compression leading to unilateral pupi llary dilation and ptosis. Factitious disorder (Choice F) refers to a psychiatric disorder in which patients falsely present themselves or others as ill or injured. HIV encephalopathy (Choice G) can cause chronic neurocognitive impaiirment and behavioral changes. It would be un likely in this patient with acute altered mental status. lnfratentorial lesions (Choice H) are associated with mu ltiple sclerosis or tumors in children. Multiple sclerosis is an autoimmune demyelinating disease that presents with focal neurologic deficits separated in space and time. Myxedema (Choice I) refers to a severe hypothyroid state, and presents with edema, lethargy, hypotension, and electrolyte disturbances, not with acute-onset hyperventilation and loss of consciousness following trauma. Salicylate intoxication (Choice J) can present with hyperventilation, gastrointestinal upset, hyperthermia, tinnitus, agitation, delirium, and hallucinations. Salicylates cause respiratory alkalosis and metabolic acidosis as a result of decoupling of the electron transport chain. Educational Objective: Epidural hematoma is classically associated with trauma to the midd le meningeal artery and can present with an initial lucid interval followed by deterioration of mental status caused by arterial bleeding and hematoma expansion. Uncal herniation involves the uncus compressing the midbrain, typical ly affecting the oculomotor nerve, causing pupi llary dilation, ptosis, and ocu lomotor nerve palsy resulting in the inferior and lateral deviation of the pupil..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 4 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 4. One day after undergoing an elective cholecystectomy, a 67-year-old woman becomes confused and bel ligerent. She has a 2-year history of mild dementia, Alzheimer type. She takes no med ications. Intramuscular haloperidol is adm inistered, and 1 hour later, she begins to repetitively hyperextend her neck. She also has repetitive conjugate upward movements of the eyes that she says she cannot control. Exam ination shows no other abnormalities. Admin istration of a med ication with which of the following properties is the most appropriate treatment? A) Antichol inerg ic B) Antidopaminerg ic C) Antiserotonergic D) Cholinerg ic E) Dopaminergic F) Serotonergic Correct Answer: A. Acute dystonias can occur in response to antipsychotics, such as haloperidol, antiepileptic drugs, or antiemetics. Common presentations include torticollis (head tilted to the side and down), retrocollis (head tilted back), opisthotonos (arching of the back), and oculogyric crisis (upward deviation of the eyes). It rarely presents with laryngospasm and strider. These movements are involuntary and cannot be controlled by the patient. The pathophysiology is an imbalance in the dopaminergic-cholinergic pathways of the basal ganglia. Risk factors for development include male sex, young age, recent cocaine use, and a history of previous acute dystonic reaction. Acute dystonias are treated with diphenhydramine or benztropine, both of which are anticholinergic medications that work to restore the proper balance in the dopaminergic and cholinergic pathways. Incorrect Answers: B, C, D, E, and F. Antidopaminergic (Choice B) agents are used primarily in the treatment of schizophrenia and include agents such as haloperidol. Antidopaminergic agents can also be used to treat nausea. As acute dystonias are caused by an imbalance in the dopaminergic and cholinergic pathways, further antagonism of dopamine would likely worsen symptoms. Antiserotonergic (Choice C) medications are used to treat nausea, especially chemotherapy-induced nausea and emesis. Some antidepressants and antipsychotics also have antiserotonergic activity. However, serotonin is not involved in the pathophysiology of acute dystonia. Cholinergic (Choice D) agents increase the amount of acetylcholine present in the neuromuscular junction, which leads to increased muscular contraction. They can be used to treat myasthenia gravis, to reverse neuromuscular blockade, and to improve symptoms associated with Alzheimer disease. Choliner ic a ents would worsen this atient's acute d stonia. Previous Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 4 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment... Correct Answer: A. Acute dystonias can occur in response to antipsychotics, such as haloperidol, antiepileptic drugs, or antiemetics. Common presentations include torticollis (head tilted to the side and down), retrocollis (head tilted back), opisthotonos (arching of the back), and oculogyric crisis (upward deviation of the eyes). It rarely presents with laryngospasm and strider. These movements are involuntary and cannot be controlled by the patient. The pathophysiology is an imbalance in the dopaminergic-cholinergic pathways of the basal ganglia. Risk factors for development include male sex, young age, recent cocaine use, and a history of previous acute dystonic reaction. Acute dystonias are treated with diphenhydramine or benztropine, both of which are anticholinergic medications that work to restore the proper balance in the dopaminergic and cholinergic pathways. Incorrect Answers: B, C, D, E, and F. Antidopaminergic (Choice B) agents are used primarily in the treatment of schizophrenia and include agents such as haloperidol. Antidopaminergic agents can also be used to treat nausea. As acute dystonias are caused by an imbalance in the dopaminergic and cholinergic pathways, further antagonism of dopamine would likely worsen symptoms. Antiserotonergic (Choice C) medications are used to treat nausea, especially chemotherapy-induced nausea and emesis. Some antidepressants and antipsychotics also have antiserotonergic activity. However, serotonin is not involved in the pathophysiology of acute dystonia. Cholinergic (Choice D) agents increase the amount of acetylcholine present in the neuromuscular junction, which leads to increased muscular contraction. They can be used to treat myasthenia gravis, to reverse neuromuscular blockade, and to improve symptoms associated with Alzheimer disease. Cholinergic agents would worsen this patient's acute dystonia. Dopaminergic (Choice E) drugs are used to treat Parkinson disease by increasing the amount of dopamine available in the nigrostriatal pathway. This leads to increased movement and improvements in bradykinesia. Dopaminergic agents would not improve acute dystonia. Serotonergic (Choice F) medications primarily include antidepressant medications. Serotonin is not involved in the pathophysiology of acute dystonia. Educational Objective: Acute dystonia most commonly occurs in response to typical antipsychotics and presents with torticollis, retrocollis, opisthotonos, and oculogyric crisis. Treatment involves anticholinergic medications, such as diphenhydramine or benztropine..,. r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 5 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 5. A previously healthy 32-year-old woman comes to the physician because of a 1-week history of progressive sensory loss. Initially, only her feet felt numb, but the loss of sensation has slowly ascended symmetrically to the umbilicus. She also has had urinary urgency and frequency, nocturia, and the perception of a tight band-like sensation around her midabdominal region. Examination shows slowing of left eye adduction during saccad ic movement of the eyes to the rig ht. There is diffuse hyperreflexia. Sensation to pinprick is decreased to the level of the umbilicus. Which of the following is the most likely diagnosis? A) Adrenal leukodystrophy B) Cytomegalovirus polyrad icu lopathy C) Guillain-Barre syndrome D) Multiple cerebral infarcts E) Multiple sclerosis Correct Answer: E. Multiple sclerosis, the most prevalent immune-mediated demyelinating disease, may present initially with transverse myelitis though can also demonstrate neurologic symptoms from lesions in other central nervous system (CNS) locations. Transverse myelitis refers to inflammation that extends transversely across the spinal cord, leading to bilateral sensory, motor, or autonomic dysfunction. When sensory tracts are involved, sensory deficits are evident at a clear dermatomal level (also known as a sensory level, likely T10 in this patient) and may present as a band-like sensation at that level. Autonomic symptoms may present as urinary urgency or incontinence, bowel incontinence, or sexual dysfunction. According to the McDonald criteria for multiple sclerosis diagnosis, patients must have evidence of demyelinating lesions that are separated in time and location. This evidence can be based on subjective symptoms or imaging evidence. This patient presents with evidence of lesions separated in space (a T10 spinal cord lesion, a lesion potentially affecting the medial longitudinal fasciculus, several corticospinal tract lesions as evidenced by diffuse hyperreflexia). Though the patient did not experience discrete symptomatic episodes separated by time, the presence of multiple lesions in discrete locations makes multiple sclerosis the most likely diagnosis (as the other deficits likely arose at different times). MRI of the brain typically shows white matter hyperintensities in the periventricular region, cortex, subcortical region, cerebellum, or spine. Oligoclonal bands of immunoglobulins, indicating immune overactivation, can be found in the cerebrospinal fluid but are not necessary for diagnosis. Treatment includes corticosteroids for symptomatic management of acute flares and long-term disease-modifying treatments such as interferon or monoclonal antibodies. Incorrect Answers: A, B, C, and D. Adrenal leukodystrophy (Choice A) is a rare X-linked peroxisomal disorder that results from the accumulation of very long fatty acid chains in various tissues. As a result of peripheral neuropathy and myelopathy, female carriers of the disorder may present with bilateral spastic paraparesis, sphincter dysfunction, neurogenic bladder, and sexual dysfunction. However, multiple sclerosis is more common,.... --- - - - - - - -- - - - -- - - - - - - -- - - -- - -- - --- -- --- - -- - --- r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 5 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment... E) Multiple sclerosis Correct Answer: E. Multiple sclerosis, the most prevalent immune-mediated demyelinating disease, may present initially with transverse myelitis though can also demonstrate neurologic symptoms from lesions in other central nervous system (CNS) locations. Transverse myelitis refers to inflammation that extends transversely across the spinal cord, leading to bilateral sensory, motor, or autonomic dysfunction. When sensory tracts are involved, sensory deficits are evident at a clear dermatomal level (also known as a sensory level, likely T10 in this patient) and may present as a band-like sensation at that level. Autonomic symptoms may present as urinary urgency or incontinence, bowel incontinence, or sexual dysfunction. According to the McDonald criteria for multiple sclerosis diagnosis, patients must have evidence of demyelinating lesions that are separated in time and location. This evidence can be based on subjective symptoms or imaging evidence. This patient presents with evidence of lesions separated in space (a T10 spinal cord lesion, a lesion potentially affecting the medial longitudinal fasciculus, several corticospinal tract lesions as evidenced by diffuse hyperreflexia). Though the patient did not experience discrete symptomatic episodes separated by time, the presence of multiple lesions in discrete locations makes multiple sclerosis the most likely diagnosis (as the other deficits likely arose at different times). MRI of the brain typically shows white matter hyperintensities in the periventricular region, cortex, subcortical region, cerebel lum, or spine. Oligoclonal bands of immunoglobulins, indicating immune overactivation, can be found in the cerebrospinal fluid but are not necessary for diagnosis. Treatment includes corticosteroids for symptomatic management of acute flares and long-term disease-modifying treatments such as interferon or monoclonal antibodies. Incorrect Answers: A, B, C, and D. Adrenal leukodystrophy (Choice A) is a rare X-linked peroxisomal disorder that resu lts from the accumulation of very long fatty acid chains in various tissues. As a result of peripheral neuropathy and myelopathy, female carriers of the disorder may present with bi lateral spastic paraparesis, sphincter dysfunction, neurogenic bladder, and sexual dysfunction. However, multiple sclerosis is more common, and transverse myelitis is more typical of mu ltiple sclerosis than adrenal leukodystrophy. Cytomegalovirus (CMV) polyradiculopathy (Choice B) is a rare condition occurring in immunocompromised patients involving inflammation of multiple nerve roots. A sensory level and hyperreflexia are instead typical of CNS disease. Guil lain-Barre syndrome (Choice C) is an inflammatory demyelinating polyneuropathy that presents with acute-onset, symmetric, ascending muscle weakness with hyporeflexia. Bulbar dysfunction and autonomic dysfunction may occur. This patient does not possess muscle weakness and demonstrates hyperreflexia, indicating an upper motor neuron lesion rather than peripheral nerve lesions. Multiple cerebral infarcts (Choice D) may cause a combination of motor, sensory, and autonomic findings. Hyperreflexia and dysfunction of the oculomotor muscles may be demonstrated. However, a sensory level is more consistent with a spinal cord lesion. This otherwise healthy young woman lacks risk factors for cerebral infarct..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 5 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment Multiple sclerosis, the most prevalent immune-mediated demyelinating disease, may present initially with transverse myelitis though... can also demonstrate neurologic symptoms from lesions in other central nervous system (CNS) locations. Transverse myelitis refers to inflammation that extends transversely across the spinal cord, leading to bilateral sensory, motor, or autonomic dysfunction. When sensory tracts are involved, sensory deficits are evident at a clear dermatomal level (also known as a sensory level, likely T10 in this patient) and may present as a band-like sensation at that level. Autonomic symptoms may present as urinary urgency or incontinence, bowel incontinence, or sexual dysfunction. According to the McDonald criteria for multiple sclerosis diagnosis, patients must have evidence of demyelinating lesions that are separated in time and location. This evidence can be based on subjective symptoms or imaging evidence. This patient presents with evidence of lesions separated in space (a T10 spinal cord lesion, a lesion potentially affecting the medial longitudinal fasciculus, several corticospinal tract lesions as evidenced by diffuse hyperreflexia). Though the patient did not experience discrete symptomatic episodes separated by time, the presence of multiple lesions in discrete locations makes multiple sclerosis the most likely diagnosis (as the other deficits likely arose at different times). MRI of the brain typically shows white matter hyperintensities in the periventricular region, cortex, subcortical region, cerebellum, or spine. Oligoclonal bands of immunoglobulins, indicating immune overactivation, can be found in the cerebrospinal fluid but are not necessary for diagnosis. Treatment includes corticosteroids for symptomatic management of acute flares and long-term disease-modifying treatments such as interferon or monoclonal antibodies. Incorrect Answers: A, B, C, and D. Adrenal leukodystrophy (Choice A) is a rare X-linked peroxisomal disorder that results from the accumulation of very long fatty acid chains in various tissues. As a result of peripheral neuropathy and myelopathy, female carriers of the disorder may present with bilateral spastic paraparesis, sphincter dysfunction, neurogenic bladder, and sexual dysfunction. However, multiple sclerosis is more common, and transverse myelitis is more typical of multiple sclerosis than adrenal leukodystrophy. Cytomegalovirus (CMV) polyradiculopathy (Choice B) is a rare condition occurring in immunocompromised patients involving inflammation of multiple nerve roots. A sensory level and hyperreflexia are instead typical of CNS disease. Guillain-Barre syndrome (Choice C) is an inflammatory demyelinating polyneuropathy that presents with acute-onset, symmetric, ascending muscle weakness with hyporeflexia. Bulbar dysfunction and autonomic dysfunction may occur. This patient does not possess muscle weakness and demonstrates hyperreflexia, indicating an upper motor neuron lesion rather than peripheral nerve lesions. Multiple cerebral infarcts (Choice D) may cause a combination of motor, sensory, and autonomic findings. Hyperreflexia and dysfunction of the oculomotor muscles may be demonstrated. However, a sensory level is more consistent with a spinal cord lesion. This otherwise healthy young woman lacks risk factors for cerebral infarct. Educational Objective: Multiple sclerosis is an autoimmune demyelinating disease that presents with focal neurologic deficits separated in space and time. Patients with multiple sclerosis may present initially with transverse myelitis, which may demonstrate a sensory level and a band-like sensation, along with possible autonomic and motor symptoms..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 6 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 6. A 67-year-old woman is brought to the physician 3 hours after a 5-m inute episode of visual loss in her left eye. She has not had any other symptoms. She has hypertension and stable angina pectoris. Medications include lisinopril and metoprolol. Her pulse is 72/min, and blood pressure is 150/92 mm Hg. Fu nduscopic exam ination shows no abnormalities. A grade 3/6 holosystolic murmur is heard best at the apex. Neurologic exam ination shows no focal findings. Which of the following is the most appropriate next step in diagnosis? A) Complete blood count B) Measurement of erythrocyte sed imentation rate C) Visual field testing D) MRI of the brain E) Carotid duplex ultrasonograph~ F) Ocular tonometry Correct Answer: E. Amaurosis fugax describes brief episodes of transient, unilateral vision loss and is indicative of retinal ischemia caused by either microembolization or inflammation of the ophthalmic artery. It often precedes the onset of central retinal artery occlusion , which is considered an ophthalmic stroke. In the absence of signs and symptoms of giant cell arteritis, such as fever, chills, weight loss, temporal headache and tenderness, or jaw claudication, amaurosis fugax is most suggestive of embolic retinal ischemia and should prompt an emergent evaluation for sources of emboli. The majority of emboli to the ophthalmic vasculature originate from the carotid arteries and cardiac valves. Evaluation should include prompt carotid duplex ultrasonography, as well as echocardiography. Treatment of carotid vascular or cardiac valvular disease can prevent central retinal arterial occlusion, which may cause irreversible blindness. Incorrect Answers: A, B, C, D, and F. Complete blood count (Choice A) and measurement of erythrocyte sedimentation rate (Choice B) are useful for the diagnosis of giant cell arteritis, which often presents with amaurosis fugax, thrombocytosis, and an increased erythrocyte sedimentation rate. However, this patient's lack of other symptoms renders carotid arterial disease, rather than giant cell arteritis, as the more likely cause of her amaurosis fugax. Visual field testing (Choice C) may be useful for the diagnosis of glaucoma or cortical vision loss. Delaying the search for embolic sources while pursuing other diagnostic tests puts the patient at risk for ischemic stroke and blindness. MRI of the brain (Choice D) may be useful for the diagnosis of optic neuritis. It is not useful for identifying the source of emboli that are causing this patient's amaurosis fugax. Vision loss secondary to optic neuritis typically lasts for several days or weeks, rather than minutes..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 6 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment F) Ocular tonometry... Correct Answer: E. Amaurosis fugax describes brief episodes of transient, unilateral vision loss and is indicative of retinal ischemia caused by either microembolization or inflammation of the ophthalmic artery. It often precedes the onset of central retinal artery occlusion, which is considered an ophthalmic stroke. In the absence of signs and symptoms of giant cell arteritis, such as fever, chills, weight loss, temporal headache and tenderness, or jaw claudication, amaurosis fugax is most suggestive of embolic retinal ischemia and should prompt an emergent evaluation for sources of emboli. The majority of emboli to the ophthalmic vasculature originate from the carotid arteries and cardiac valves. Evaluation should include prompt carotid duplex ultrasonography, as well as echocardiography. Treatment of carotid vascular or cardiac valvular disease can prevent central retinal arterial occlusion, which may cause irreversible blindness. Incorrect Answers: A, B, C, D, and F. Complete blood count (Choice A) and measurement of erythrocyte sedimentation rate (Choice B) are useful for the diagnosis of giant cel l arteritis, which often presents with amaurosis fugax, thrombocytosis, and an increased erythrocyte sedimentation rate. However, this patient's lack of other symptoms renders carotid arterial disease, rather than giant cell arteritis, as the more likely cause of her amaurosis fugax. Visual field testing (Choice C) may be useful for the diagnosis of glaucoma or cortical vision loss. Delaying the search for embolic sources while pursuing other diagnostic tests puts the patient at risk for ischemic stroke and blindness. MRI of the brain (Choice D) may be useful for the diagnosis of optic neuritis. It is not useful for identifying the source of emboli that are causing this patient's amaurosis fugax. Vision loss secondary to optic neuritis typically lasts for several days or weeks, rather than minutes. Ocular tonometry (Choice F) allows for the measurement of intraocular pressure and is useful for the diagnosis of glaucoma, which is characterized by slowly progressive optic nerve damage in the setting of increased intraocular pressure. The vision loss caused by glaucoma is insidious and characterized by initial peripheral vision loss with slow encroachment upon central vision. Glaucoma does not present with amaurosis fugax. Educational Objective: Amaurosis fugax describes brief episodes of transient, unilateral vision loss and is indicative of retinal ischemia as a result of emboli. It often precedes the onset of central retinal artery occlusion, which is an ophthalmic stroke. Patients who present with amaurosis fugax should undergo an emergent evaluation with carotid duplex ultrasonography and echocardiography to prevent an ischemic stroke of the eye or of the brain..,. r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 7 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 7. An 11-year-old girl is brought to the emergency department by her mother because of a 2-day history of increasing weakness and a prickling sensation in her legs. She was previously healthy except for a mi ld flu-like illness during the past week. Her temperature is 37°C (98.6°F), pulse is 78/min, respirations are 20/min, and blood pressure is 115/70 mm Hg. Exam ination of the lower extremities shows a muscle strength of 1/5 and decreased sensation to pinprick. Achilles tendon and patellar reflexes are decreased. The remainder of the exam ination shows no abnormalities. A lumbar puncture is performed. Analysis of cerebrospinal fluid shows a total protein concentration of 80 mg/dl and a leukocyte count of 4/mm 3. In addition to close observation, oxygen therapy, and maintenance of fl uids, which of the following is the most appropriate pharmacotherapy? A) Antibiotics B) Anticonvulsants C) Antivirals D) Corticosteroids E) Immune globulins Correct Answer: E. This patient most likely has Guillain-Barre syndrome (GBS), leading to polyneuropathy, which is typically treated with immune globulins or plasma exchange. In GBS, a preceding infection (eg, Campylobacter jejuni, influenza-like illnesses) leads to autoimmune cross- reactivity with the myelin of the nerve roots exiting the spinal cord. The ventral nerve roots, containing motor and sympathetic efferents, are most commonly involved, though the dorsal nerve root (controlling sensation) may also be affected. As such, patients typically present with acute symmetric muscle weakness with depressed or absent deep tendon reflexes (reflecting a lower motor neuron pattern of dysfunction) that begins in the lower extremities and may rapidly ascend to involve the upper extremities, bulbar muscles, or respiratory muscles. Autonomic dysfunction (eg, blood pressure fluctuations, cardiac irregularities) is common. Sensory deficits and pain can also occur (though these symptoms are typically mild compared to motor dysfunction). The diagnosis is confirmed by increased cerebrospinal fluid protein with normal cel l counts on lumbar puncture, termed albuminocytologic dissociation, thought to reflect generalized inflammation. Management includes respiratory support and, for severe cases, plasma exchange or intravenous immunoglobulin therapy. Intravenous immunoglobulin therapy may work by neutralizing the cross-reactive antibodies that cause GBS. Incorrect Answers: A, B, C, and D. Antibiotics (Choice A) and antivirals (Choice C) may play a role in treating the infectious illnesses that precede GBS. However, these agents do not improve the symptoms of GBS. Anticonvulsants (Choice B) are utilized to treat seizure disorders but play no role in the treatment of GBS. r ~, - - -- - - - - - - - - - - - -. Corticosteroids (Choice D) treat some autoimmune conditions, such as multiple sclerosis. However, corticosteroids have not - - - - - -- - - -- - - -- - - ~ ~ r,.... Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 7 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment i..... - ~, - · C) Antivirals D) Corticosteroids E) Immune globulins Correct Answer: E. This patient most likely has Guillain-Barre syndrome (GBS), leading to polyneuropathy, which is typically treated with immune globulins or plasma exchange. In GBS, a preceding infection (eg, Campy/obacter Jejuni, influenza-like illnesses) leads to autoimmune cross- reactivity with the myelin of the nerve roots exiting the spinal cord. The ventral nerve roots, containing motor and sympathetic efferents, are most commonly involved, though the dorsal nerve root (controlling sensation) may also be affected. As such, patients typical ly present with acute symmetric muscle weakness with depressed or absent deep tendon reflexes (reflecting a lower motor neuron pattern of dysfunction) that begins in the lower extremities and may rapidly ascend to involve the upper extremities, bulbar muscles, or respiratory muscles. Autonomic dysfunction (eg, blood pressure fluctuations, cardiac irregularities) is common. Sensory deficits and pain can also occur (though these symptoms are typically mild compared to motor dysfunction). The diagnosis is confirmed by increased cerebrospinal fluid protein with normal cel l counts on lumbar puncture, termed albuminocytologic dissociation, thought to reflect generalized inflammation. Management includes respiratory support and, for severe cases, plasma exchange or intravenous immunoglobulin therapy. Intravenous immunoglobulin therapy may work by neutralizing the cross-reactive antibodies that cause GBS. Incorrect Answers: A, B, C, and D. Antibiotics (Choice A) and antivirals (Choice C) may play a role in treating the infectious illnesses that precede GBS. However, these agents do not improve the symptoms of GBS. Anticonvulsants (Choice B) are utilized to treat seizure disorders but play no role in the treatment of GBS. Corticosteroids (Choice D) treat some autoimmune conditions, such as multiple sclerosis. However, corticosteroids have not demonstrated efficacy for GBS in randomized control led trials. Educational Objective: Guillain-Barre syndrome arises from an autoimmune attack of the spinal nerve roots and typically presents with acute-onset, symmetric, ascending muscle weakness with hyporeflexia. Many patients also demonstrate autonomic dysfunction or sensory symptoms. The diagnosis is confirmed by increased cerebrospinal fluid protein with normal cell counts on lumbar puncture, and treatment requires plasma exchange or intravenous immunoglobulin therapy..,. r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 8 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 8. A 42-year-old woman with alcoholism has severe burni ng paresthesias of both feet and decreased vibratory sensation in both ankles 2 months after begin ning treatment for active, cavitary pulmonary tuberculosis. At the time of diagnosis she was malnourished, and isoniazid, rifampin, ethambutol, vitami n B 6, and folic acid were prescribed. The most likely cause of paresthesias of her feet and decreased sensation in her ankles is failure to take wh ich of the following prescribed med ications? A) Ethambutol B) Folic acid C) lsoniazid D) Rifam pin E) Vitam in B 6 Correct Answer: E. Primary tuberculosis results from an initial exposure to Mycobacterium tuberculosis, leading to the development of hilar lymphadenopathy and a Ghon focus (Ghon complex), as in this case. In the primary infection, patients present with subacute fevers, weight loss, night sweats, cough, and malaise. Active tuberculosis is treated primarily with a combination of rifampin, isoniazid, pyrazinamide, and ethambutol. lsoniazid binds vitamin B 6 (pyridoxine) which may result in early excretion and inactivation of pyridoxine, and also inhibits pyridoxine phosphokinase, which is necessary to activate it. Pyridoxine deficiency then results, of which the primary symptoms are peripheral neuropathy or paresthesia. Therefore, al l patients taking isoniazid concurrently take pyridoxine supplementation. Pyridoxine deficiency limits synthesis of histamine, hemoglobin, and neurotransmitters including epinephrine, norepinephrine, dopamine, serotonin, and y-aminobutyric acid (GABA). In addition to peripheral neuropathy, deficiency commonly presents with dermatitis, sideroblastic anemia, glossitis, and seizures. Incorrect Answers: A, B, C, and D. Ethambutol (Choice A) is used to treat mycobacterial infection. It neither contributes to nor prevents vitamin B 6 deficiency. Its primary side effects include optic neuropathy, neutropenia, and thrombocytopenia. Folic acid (Choice B) is converted to tetrahydrofolic acid and is used as a coenzyme in the synthesis of nucleotides and nucleosides. Folate is contained in leafy vegetables and absorbed in the jejunum. Folate deficiency is often seen in patients with malnutrition, alcohol use disorder, and patients taking anti-folate medications (eg, phenytoin, methotrexate). It is not caused by any of the medications used to treat tuberculosis. lsoniazid (Choice C) binds vitamin B 6 and leads to deficiency if not adequately supplemented. Deficiency of vitamin B 6 causes peripheral neuropathy, as in this case. If the patient fai led to take isoniazid, she would not experience this side effect, though her.... -- - -- - - - - - - - - - - - - - - -- - -- -- r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 8 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment... D) Rifampin E) Vitam in B 6 Correct Answer: E. Primary tuberculosis results from an initial exposure to Mycobacterium tuberculosis, leading to the development of hilar lymphadenopathy and a Ghan focus (Ghan complex), as in this case. In the primary infection, patients present with subacute fevers, weight loss, night sweats, cough, and malaise. Active tuberculosis is treated primarily with a combination of rifampin, isoniazid, pyrazinamide, and ethambutol. lsoniazid binds vitamin B 6 (pyridoxine) which may result in early excretion and inactivation of pyridoxine, and also inhibits pyridoxine phosphokinase, which is necessary to activate it. Pyridoxine deficiency then results, of which the primary symptoms are peripheral neuropathy or paresthesia. Therefore, al l patients taking isoniazid concurrently take pyridoxine supplementation. Pyridoxine deficiency limits synthesis of histamine, hemoglobin, and neurotransmitters including epinephrine, norepinephrine, dopamine, serotonin, and y-aminobutyric acid (GABA). In addition to peripheral neuropathy, deficiency commonly presents with dermatitis, sideroblastic anemia, glossitis, and seizures. Incorrect Answers: A, B, C, and D. Ethambutol (Choice A) is used to treat mycobacterial infection. It neither contributes to nor prevents vitamin B 6 deficiency. Its primary side effects include optic neuropathy, neutropenia, and thrombocytopenia. Folic acid (Choice B) is converted to tetrahydrofolic acid and is used as a coenzyme in the synthesis of nucleotides and nucleosides. Folate is contained in leafy vegetables and absorbed in the jejunum. Folate deficiency is often seen in patients with malnutrition, alcohol use disorder, and patients taking anti-folate medications (eg, phenytoin, methotrexate). It is not caused by any of the medications used to treat tuberculosis. lsoniazid (Choice C) binds vitamin B 6 and leads to deficiency if not adequately supplemented. Deficiency of vitamin B 6 causes peripheral neuropathy, as in this case. If the patient fai led to take isoniazid, she would not experience this side effect, though her tuberculosis infection would be suboptimally treated. Rifampin (Choice D) is an anti-tuberculosis drug that increases the activity of the CYP450 enzymes in the liver. It also causes bodily fluids to exhibit an orange tinge. It does not affect concentrations of vitamin B5- Educational Objective: lsoniazid therapy for latent tuberculosis without sufficient pyridoxine supplementation can lead to pyridoxine deficiency. This is characterized by peripheral neuropathy, dermatitis, sideroblastic anemia, glossitis, and seizures..,. r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 9 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 9. A 20-year-old college student comes to the physician for a follow-up examination 2 days after sustaining a head injury when he ran into another player while playing flag football. He did not lose consciousness but does not remember anything from the rest of the game. He was evaluated in the emergency department 1 hour after the injury; a CT scan of the head showed no abnormalities and he was discharged. Today, he reports a mi ld, persistent headache that improves with acetaminophen. He has not had nausea, vomiting, or memory problems and was able to return to school today. Exam ination shows no abnormalities. He asks about playing i11 a flag football playoff game tomorrow. Which of the following is the most appropriate recommendation? A) No contact sports pending evaluation in 1 wee!< B) No contact sports pending an MRI of the brai n C) No contact sports pending a lumbar puncture D) No contact sports for 1 year; schedule regular follow-up examinations E) Return to sports; no further management is indicated at this time Correct Answer: A. Mild traumatic brain injury, also known as a concussion, commonly results in loss of consciousness, confusion, amnesia, headache, dizziness, nausea, or vomiting minutes after the injury. Symptoms that commonly develop within the following days include mood disturbances, photophonophobia, trouble concentrating, or insomnia. Focal neurologic symptoms, such as limb weakness or vision changes, indicate traumatic vascular injury. As such, all patients with suspected concussion should undergo a thorough neurologic examination, and a subset of at-risk patients should receive neuroimaging. All patients should be monitored closely for 24 hours for neurologic deterioration, which may indicate a developing intracranial hematoma. To prevent cumulative brain injury (eg, from a second concussion), patients with concussion should return to their usual activities in a graded fashion, beginning with the return to school or work. Each day, a more intense activity can be introduced (eg, first light aerobic exercise), culminating with contact sports after a week in uncomplicated and improving cases. Incorrect Answers: B, C, D, and E. An MRI of the brain (Choice B) may assist in detecting occult blood products in the subacute and chronic phases in patients with persistent symptoms. Repeat imaging is not necessary for patients with improving symptoms or patients in the acute phase with stable, expected symptoms such as mild headache. A lumbar puncture (Choice C) is not typically necessary for ruling out an intracranial hematoma in the setting of suspected concussion. Neuroimaging is sufficient. Prohibiting contact sports for a year (Choice D) would be unnecessary if a patient experiences improving symptoms after the acute.... -- -- -- - - ----- - - - - - -- - --- - -- -- - - - - -- -- - - - - - -- -- - - - -- - - - - - --- - - - - - - r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 9 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment... C) No contact sports pending a lumbar puncture D) No contact sports for 1 year; schedule regular follow-up examinations E) Return to sports; no further management is indicated at this time Correct Answer: A. Mild traumatic brain injury, also known as a concussion, commonly results in loss of consciousness, confusion, amnesia, headache, dizziness, nausea, or vomiting minutes after the injury. Symptoms that commonly develop within the following days include mood disturbances, photophonophobia, trouble concentrating, or insomnia. Focal neurologic symptoms, such as limb weakness or vision changes, indicate traumatic vascular injury. As such, all patients with suspected concussion should undergo a thorough neurologic examination, and a subset of at-risk patients should receive neuroimaging. All patients should be monitored closely for 24 hours for neurologic deterioration, which may indicate a developing intracranial hematoma. To prevent cumu lative brain injury (eg, from a second concussion), patients with concussion shou ld return to their usual activities in a graded fashion, beginning with the return to school or work. Each day, a more intense activity can be introduced (eg, first light aerobic exercise), culminating with contact sports after a week in uncomplicated and improving cases. Incorrect Answers: B, C, D, and E. An MRI of the brain (Choice B) may assist in detecting occult blood products in the subacute and chronic phases in patients with persistent symptoms. Repeat imaging is not necessary for patients with improving symptoms or patients in the acute phase with stable, expected symptoms such as mild headache. A lumbar puncture (Choice C) is not typically necessary for ruling out an intracranial hematoma in the setting of suspected concussion. Neuroimaging is sufficient. Prohibiting contact sports for a year (Choice D) would be unnecessary if a patient experiences improving symptoms after the acute concussion phase. However, returning to sports immediately (Choice E) would put this patient at risk for serious progression of brain injury if another concussion were to occur. Educational Objective: Common early concussion symptoms include loss of consciousness, confusion, amnesia, headache, dizziness, nausea, or vomiting. To prevent cumulative brain injury, patients with a concussion should return to their usual activities in a graded fashion; contact sports are allowable after a week in uncomplicated and improving cases..,. r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section : Item 10 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 10. A 19-year-old woman is brought to the emergency department by paramedics after having a seizure at a dormitory party on campus. According to her boyfriend , who accompanied her, she had been drinking more water than usual and then became silent and began staring. He then witnessed her collapse to the floor and begin shaking for approximately 1 minute. On arrival, she is mute and unresponsive to questions. She appears restless and periodical ly grinds her teeth. Her tem perature is 39.6°C (103.3°F), pulse is 90/min, respirations are 24/min, and blood pressure is 150/95 mm Hg. Physical examination shows profuse diaphoresis and piloerection. Pupils are 5 mm bilaterally. The remainder of the examination shows no abnormalities. Laboratory studies show: Prothrombin time 16 sec Serum Na + 114mEq/L Urea nitrogen 40 mg/dL Creatinine 2 mg/dL ALT 90 U/L Creatine kinase 1200 U/L The most likely diagnosis is intoxication with which of the following substances? A) Amitriptyl ine B) Clonazepam C) Ecstasy (3,4-methylenedioxymethamphetamine) D) y-Hydroxybutyrate E) Phencyclidine Correct Answer: C. 3,4-methylenedioxymethamphetamine (MOMA), called ecstasy or "Mol ly," is a psychotherapeutic agent and drug of abuse. It is a stimulant and causes feelings of increased energy, euphoria, and disinhibition. Minor characteristic side effects include agitation, bruxism (grinding teeth), diaphoresis, and blurry vision. However, serious side effects also accompany ecstasy use. Autonomic instability (hypertension, tachycardia, and hyperthermia) can lead to life-threatening cardiovascular toxicity. This patient demonstrates another serious complication: hyponatremia secondary to increased water intake and secretion of anti-diuretic hormone. Severe hyponatremia may be accompanied by seizures, as seen in this case, as wel l as confusion, coma, or death. This is a particular risk in young women. Treatment includes rapid administration of hypertonic saline if recurrent seizure activity occurs, followed by gradual correction of sodium and management of autonomic instability. Incorrect Answers: A, B, D, and E..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section : Item 10 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment i · · - -,. ·· C) Ecstasy (3,4-methylenedioxymethamphetamine) 0 ) y-Hyd roxybutyrate E) Phencyclidine Correct Answer: C. 3,4-methylenedioxymethamphetamine (MOMA), called ecstasy or "Mol ly," is a psychotherapeutic agent and drug of abuse. It is a stimulant and causes feelings of increased energy, euphoria, and disinhibition. Minor characteristic side effects include agitation, bruxism (grinding teeth), diaphoresis, and blurry vision. However, serious side effects also accompany ecstasy use. Autonomic instability (hypertension, tachycardia, and hyperthermia) can lead to life-threatening cardiovascular toxicity. This patient demonstrates another serious complication: hyponatremia secondary to increased water intake and secretion of anti-diuretic hormone. Severe hyponatremia may be accompanied by seizures, as seen in this case, as wel l as confusion, coma, or death. This is a particular risk in young women. Treatment includes rapid administration of hypertonic saline if recurrent seizure activity occurs, followed by gradual correction of sodium and management of autonomic instability. Incorrect Answers: A, B, 0, and E. Amitriptyline (Choice A) is a tricyclic antidepressant (TCA). TCA overdose presents with anticholinergic side effects (hyperthermia, flushing, mydriasis, ileus, and urinary retention) and cardiac arrhythmias, generally wide ORS complex tachycardia. Neurologic manifestations include mental status changes, decreased level of consciousness, delirium, and seizures. It is not generally a drug of abuse. Clonazepam (Choice B) is a benzodiazepine. Benzodiazepine toxicity is manifest by slurred speech, ataxia, and altered mental status with normal vital signs. Seizures are a sign of benzodiazepine withdrawal, not intoxication. y-Hydroxybutyrate (Choice 0) is a sedative hypnotic that is commonly used to facilitate sexual assau lt, as it causes a state of dissociation and sedation. It is known as "Liquid G" or "GHB." It is unlikely to cause autonomic agitation, seizure, and hyperthermia as seen in this patient. Phencyclidine (PCP) (Choice E) intoxication is associated with aggression, rotatory nystagmus, and ataxia. Hyponatremia is not seen. Educational Objective: 3,4-methylenedioxymethamphetamine (MOMA), called ecstasy or "Mol ly," can potentially cause both minor and serious side effects, including autonomic instability, cardiovascu lar toxicity, and severe hyponatremia..,. r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section : Item 11 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 11. A 47-year-old man w ith a history of alcoholism is brought to the emergency department by his fam ily because of confusion. He lives alone, and they found him disoriented 4 hours ago. An empty plastic container with a sweet odor was found in his apartment. He is oriented only to place. Cranial nerves, motor strength, and sensation are normal. Serum studies show a creatinine concentration of 1.5 mg/dl, bicarbonate concentration of 8 mEq/L, and an increased anion gap. Serum ketones test is negative. Urinalysis shows crystals. Exposure to which of the following is the most likely cause of these fi ndings? A) Acetaminophen B) Arsen ic C) Carbon monoxide D) Cyanide E) Ethanol F) Ethylene glycol G) Methanol H) Organophosphate I) Sal icylates Correct Answer: F. Patients with ingestion of ethylene glycol may present similarly to patients with alcohol intoxication, with central nervous system effects such as disorientation and altered mental status. Ethylene glycol is metabolized by alcohol dehydrogenase to toxic metabolites including glycolate, glyoxylate, and oxalate. These metabolites are directly toxic to the kidneys through tubular damage as well as oxalate crystal precipitation causing tubu le obstruction, resulting in acute kidney injury. Oxalate crystals are seen on urine microscopy. These metabolites also contribute to an anion-gap metabolic acidosis. Management of ethylene glycol poisoning involves fomepizole, an alcohol dehydrogenase inhibitor that prevents metabolization of ethylene glycol to its toxic metabolites. For severe ingestions, hemodialysis to remove ethylene glycol and its metabolites may be necessary. Incorrect Answers: A, B, C, D, E, G, H, and I. Acetaminophen (Choice A) toxicity is characterized by acute liver failure. At high doses, saturation of phase II metabolic pathways leads to excess acetaminophen being metabolized by cytochrome P450-mediated reactions to N-acetyl-p-benzoquinoneimine (NAPQI), which has strong oxidizing properties and is directly hepatotoxic. Arsenic (Choice B) poisoning is uncommon and can cause dermatitis, skin cancer, neuropathy, hepatotoxicity, and in severe cases,.... -·· ·- :A: - ·- - - -· - - - - - - r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section : Item 11 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment... Correct Answer: F. Patients with ingestion of ethylene glycol may present similarly to patients with alcohol intoxication, with central nervous system effects such as disorientation and altered mental status. Ethylene glycol is metabolized by alcohol dehydrogenase to toxic metabolites including glycolate, glyoxylate, and oxalate. These metabolites are directly toxic to the kidneys through tubular damage as well as oxalate crystal precipitation causing tubu le obstruction, resulting in acute kidney injury. Oxalate crystals are seen on urine microscopy. These metabolites also contribute to an anion-gap metabolic acidosis. Management of ethylene glycol poisoning involves fomepizole, an alcohol dehydrogenase inhibitor that prevents metabolization of ethylene glycol to its toxic metabolites. For severe ingestions, hemodialysis to remove ethylene glycol and its metabolites may be necessary. Incorrect Answers: A, B, C, D, E, G, H, and I. Acetaminophen (Choice A) toxicity is characterized by acute liver failure. At high doses, saturation of phase II metabolic pathways leads to excess acetaminophen being metabolized by cytochrome P450-mediated reactions to N-acetyl-p-benzoquinoneimine (NAPQI), which has strong oxidizing properties and is directly hepatotoxic. Arsenic (Choice B) poisoning is uncommon and can cause dermatitis, skin cancer, neuropathy, hepatotoxicity, and in severe cases, systemic toxicity and death. Acute large exposure to arsenic can cause gastrointestinal distress, QT prolongation which may progress to Torsades de pointes, cardiac arrhythmias, shock, and acute respiratory distress syndrome. Carbon monoxide (CO) (Choice C) is a byproduct of combustion and poisoning occurs as a consequence of inhaling the gas. CO has an affinity for hemoglobin that is hundreds of times greater than that of oxygen, readily displacing oxygen from heme. Symptoms of CO poisoning include headache, loss of consciousness, dizziness, vomiting, and fatigue. Cyanide (Choice D) inhibits the electron transport chain, leading to lactic acidosis, compensatory respiratory alkalosis, hypotension, lethargy, and bradycardia. It would not present with acute kidney injury and crystals on urinalysis. Ethanol (Choice E) ingestion can present with altered mental status, but metabolic acidosis, crystals on urinalysis, and acute kidney injury are more likely because of ethylene glycol ingestion. Methanol (Choice G) can be metabolized to formic acid, a toxic metabolite that can cause visual disturbances, retinal edema, optic disc hyperemia, gastrointestinal distress, putaminal hemorrhage, and neurologic depression. Organophosphate (Choice H) poisoning is caused by increased concentrations of acetylcholine because of the inhibition of acetylcholinesterase. Symptoms of organophosphate poisoning include diarrhea, vomiting, urination, sweating, salivation, bronchospasm, lethargy, and possible coma. Salicylate (Choice I) toxicity can present with hyperventilation, gastrointestinal upset, hyperthermia, tinnitus, agitation, delirium, and.... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section : Item 11 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment oxalate crystal precipitation causing tubule obstruction, resulting in acute kidney injury. Oxalate crystals are seen on urine microscopy.... These metabolites also contribute to an anion-gap metabolic acidosis. Management of ethylene glycol poisoning involves fomepizole, an alcohol dehydrogenase inhibitor that prevents metabolization of ethylene glycol to its toxic metabolites. For severe ingestions, hemodialysis to remove ethylene glycol and its metabolites may be necessary. Incorrect Answers: A, B, C, D, E, G, H, and I. Acetaminophen (Choice A) toxicity is characterized by acute liver failure. At high doses, saturation of phase II metabolic pathways leads to excess acetaminophen being metabolized by cytochrome P450-mediated reactions to N-acetyl-p-benzoquinoneimine (NAPQI), which has strong oxidizing properties and is directly hepatotoxic. Arsenic (Choice B) poisoning is uncommon and can cause dermatitis, skin cancer, neuropathy, hepatotoxicity, and in severe cases, systemic toxicity and death. Acute large exposure to arsenic can cause gastrointestinal distress, QT prolongation which may progress to Torsades de pointes, cardiac arrhythmias, shock, and acute respiratory distress syndrome. Carbon monoxide (CO) (Choice C) is a byproduct of combustion and poisoning occurs as a consequence of inhaling the gas. CO has an affinity for hemoglobin that is hundreds of times greater than that of oxygen, readily displacing oxygen from heme. Symptoms of CO poisoning include headache, loss of consciousness, dizziness, vomiting, and fatigue. Cyanide (Choice D) inhibits the electron transport chain, leading to lactic acidosis, compensatory respiratory alkalosis, hypotension, lethargy, and bradycardia. It would not present with acute kidney injury and crystals on urinalysis. Ethanol (Choice E) ingestion can present with altered mental status, but metabolic acidosis, crystals on urinalysis, and acute kidney injury are more likely because of ethylene glycol ingestion. Methanol (Choice G) can be metabolized to formic acid, a toxic metabolite that can cause visual disturbances, retinal edema, optic disc hyperemia, gastrointestinal distress, putaminal hemorrhage, and neurologic depression. Organophosphate (Choice H) poisoning is caused by increased concentrations of acetylcholine because of the inhibition of acetylcholinesterase. Symptoms of organophosphate poisoning include diarrhea, vomiting, urination, sweating, salivation, bronchospasm, lethargy, and possible coma. Salicylate (Choice I) toxicity can present with hyperventilation, gastrointestinal upset, hyperthermia, tinnitus, agitation, delirium, and hallucinations. Salicylates cause respiratory alkalosis and metabolic acidosis because of the decoupling of the electron transport chain. Educational Objective: Ethylene glycol is metabolized by alcohol dehydrogenase to toxic metabolites including glycolate, glyoxylate, and oxalate. Patients present with an acute kidney injury, metabolic acidosis, and crystals on urinalysis..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section : Item 12 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 12. A 77-year-old man with hypertension comes to the physician for a routi ne follow-up examination. He feels wel l. His only med ication is a diuretic. His blood pressu re is 140/70 mm Hg. On neurologic exam ination, cranial nerves are intact. Muscle tone and strength are nor