Peripheral nerve disorders — MCQs

A 57-year-old man presents to his primary care physician with a 2-month history of right upper and lower extremity weakness. He noticed the weakness when he started falling far more frequently while running errands. Since then, he has had increasing difficulty with walking and lifting objects. His past medical history is significant only for well-controlled hypertension, but he says that some members of his family have had musculoskeletal problems. His right upper extremity shows forearm atrophy and depressed reflexes while his right lower extremity is hypertonic with a positive Babinski sign. Which of the following is most likely associated with the cause of this patient's symptoms?

A 63-year-old man presents to the clinic concerned about numbness and weakness in his bilateral shoulders and arms for the past 8 weeks. The symptoms started when he fell from scaffolding at work and landed on his back. Initial workup was benign and he returned to normal duty. However, his symptoms have progressively worsened since the fall. He denies fever, back pain, preceding vomiting, and diarrhea. He has a history of type 2 diabetes mellitus, hypertension, hypercholesterolemia, ischemic heart disease, and a 48-pack-year cigarette smoking history. He takes atorvastatin, hydrochlorothiazide, lisinopril, labetalol, and metformin. His blood pressure is 132/82 mm Hg, the pulse is 72/min, and the respiratory rate is 15/min. All cranial nerves are intact. Muscle strength is reduced in the upper limbs (4/5 bilaterally) but normal in the lower limbs. Perception of sharp stimuli and temperature is reduced on his shoulders and upper arms. The vibratory sense is preserved. Sensory examination is normal in the lower limbs. What is the most likely diagnosis?

A 61-year-old woman comes to the physician for evaluation of numbness and a burning sensation in her feet for the past 5 months. She has type 2 diabetes mellitus and hypercholesterolemia. Her blood pressure is 119/82 mm Hg. Neurologic examination shows decreased sensation to pinprick, light touch, and vibration over the soles of both feet. There is a nontender ulcer on the plantar surface of her left foot. Pedal pulses are strong bilaterally. Her hemoglobin A1c concentration is 8.6%. Which of the following processes is most likely involved in the pathogenesis of this patient's current symptoms?

A 28-year-old man presents to the emergency department with lower extremity weakness. He was in his usual state of health until 10 days ago. He then began to notice his legs were “tiring out” during his workouts. This progressed to difficulty climbing the stairs to his apartment. He has asthma and uses albuterol as needed. He has no significant surgical or family history. He smokes marijuana daily but denies use of other recreational drugs. He is sexually active with his boyfriend of 2 years. He has never traveled outside of the country but was camping 3 weeks ago. He reports that he had diarrhea for several days after drinking unfiltered water from a nearby stream. On physical examination, he has 1/5 strength in his bilateral lower extremities. He uses his arms to get up from the chair. Achilles and patellar reflexes are absent. A lumbar puncture is performed, and results are as shown below: Cerebral spinal fluid: Color: Clear Pressure: 15 cm H2O Red blood cell count: 0 cells/µL Leukocyte count: 3 cells/ µL with lymphocytic predominance Glucose: 60 mg/dL Protein: 75 mg/dL A culture of the cerebral spinal fluid is pending. Which of the following is the part of the management for the patient’s most likely diagnosis?

A 26-year-old man presents to his primary doctor with one week of increasing weakness. He reports that he first noticed difficulty walking while attending his sister's graduation last week, and yesterday he had difficulty taking his coffee cup out of the microwave. He remembers having nausea and vomiting a few weeks prior, but other than that has no significant medical history. On exam, he has decreased reflexes in his bilateral upper and lower extremities, with intact sensation. If a lumbar puncture is performed, which of the following results are most likely?

A 35-year-old man is transferred to the intensive care unit after a motorcycle accident. He does not open his eyes with painful stimuli. He makes no sounds. He assumes decerebrate posture with sternal rub. His right eye is abnormally positioned downward and outward and has a dilated pupil which is not responsive to light. In contrast to this patient's findings, one would expect a patient with a diabetic mononeuropathy of the oculomotor nerve to present in which fashion?

A 44-year-old woman presents to her primary care physician’s office with episodes of pain in her right hand. She says that the pain is most significant at night and awakens her from sleep numerous times. When she experiences this pain, she immediately puts her hand under warm running water or shakes her hand. She has also experienced episodes of numbness in the affected hand. Driving and extending the right arm also provoke her symptoms. She denies any trauma to the hand or associated weakness. Medical history is notable for hypothyroidism treated with levothyroxine. She works as a secretary for a law firm. On physical exam, when the patient hyperflexes her wrist, pain and paresthesia affect the first 3 digits of the right hand. Which of the following is the confirmatory diagnostic test for this patient?

An 8-year-old boy is brought to the pediatrician because his mother is concerned about recent behavioral changes. His mother states that she has started to notice that he is slurring his speech and seems to be falling more than normal. On exam, the pediatrician observes the boy has pes cavus, hammer toes, and kyphoscoliosis. Based on these findings, the pediatrician is concerned the child has a trinucleotide repeat disease. Which of the following trinucleotide repeats is this child most likely to possess?

A 67-year-old woman comes to the physician because of a 3-week history of fatigue and worsening back and abdominal pain. During this period, she has also had excessive night sweats and a 4.6-kg (10-lb) weight loss. She has had swelling of the neck for 3 days. She does not smoke or drink alcohol. Vital signs are within normal limits. Physical examination shows a 4-cm, supraclavicular, nontender, enlarged and fixed lymph node. The spleen is palpated 2 cm below the left costal margin. Laboratory studies show: Hemoglobin 10.4 g/dL Mean corpuscular volume 87 μm3 Leukocyte count 5,200/mm3 Platelet count 190,000/mm3 Serum Lactate dehydrogenase 310 U/L A CT scan of the thorax and abdomen shows massively enlarged paraaortic, axillary, mediastinal, and cervical lymph nodes. Histopathologic examination of an excised cervical lymph node shows lymphocytes with a high proliferative index that stain positive for CD20. Which of the following is the most likely diagnosis?

A 31-year-old Israeli male with a history of heavy smoking presents to your office with painful ulcerations on his hands and feet. Upon examination, he is found to have hypersensitivity to intradermally injected tobacco extract. Which of the following processes is most likely responsible for his condition?