Amyotrophic lateral sclerosis — MCQs

A 53-year-old woman comes to the physician because of a 3-year history of increasing weakness of her extremities and neck pain that is worse on coughing or sneezing. She first noticed weakness of her right upper extremity 3 years ago, which progressed to her right lower extremity 2 years ago, her left lower extremity 1 year ago, and her left upper extremity 6 months ago. She has had difficulty swallowing and speaking for the past 5 months. Vital signs are within normal limits. Examination shows an ataxic gait. Speech is dysarthritic. Muscular examination shows spasticity and muscle strength is decreased in all extremities. There is bilateral atrophy of the sternocleidomastoid and trapezius muscles. Deep tendon reflexes are 4+ bilaterally. Plantar response shows an extensor response bilaterally. Sensation is decreased below the C5 dermatome bilaterally. Which of the following is the most likely cause of this patient's symptoms?

A 62-year-old woman is brought to the physician because of 6 months of progressive weakness in her arms and legs. During this time, she has also had difficulty swallowing and holding her head up. Examination shows pooling of oral secretions. Muscle strength and tone are decreased in the upper extremities. Deep tendon reflexes are 1+ in the right upper and lower extremities, 3+ in the left upper extremity, and 4+ in the left lower extremity. Sensation to light touch, pinprick, and vibration are intact. Which of the following is the most likely diagnosis?

A 29-year-old man comes to the emergency department because of progressively worsening fatigue and shortness of breath for the past 2 weeks. His only medication is insulin. Examination shows elevated jugular venous distention and coarse crackles in both lungs. Despite appropriate life-saving measures, he dies. Gross examination of the heart at autopsy shows concentrically thickened myocardium and microscopic examination shows large cardiomyocytes with intracellular iron granules. Examination of the spinal cord shows atrophy of the lateral corticospinal tracts, spinocerebellar tracts, and dorsal columns. Which of the following is the most likely underlying cause of this patient's condition?

A 49-year-old man presents to his primary care physician complaining of multiple symptoms. He states that over the past 8 months he has noticed voice changes and difficulty swallowing. The dysphagia started with just dry foods like crackers but has progressed to include smoothies and ice cream. He works as a newspaper editor and has also noticed trouble writing with his dominant hand. He is accompanied by his wife, who complains that he snores and drools in his sleep. His medical history is significant for hypertension and a bicuspid aortic valve. He takes hydrochlorothiazide. On physical examination, there is atrophy of the right hand. The patient’s speech is slow. A systolic murmur at the right upper sternal border is appreciated. Tapping of the left patellar tendon causes the patient’s left lower extremity to forcefully kick out. Stroking of the plantar aspect of the patient’s left foot causes his left toes to extend upward. Which of the following therapies is most likely to slow the progression of the patient’s symptoms?

An 82-year-old comes to the physician for a routine checkup. He feels well. He has a history of hypertension, peripheral vascular disease, carotid stenosis, and mild dementia. His father had Parkinson's disease and died of a stroke at the age of 74 years. He has smoked one-half pack of cigarettes daily for 30 years but quit at the age of 50 years. He drinks alcohol in moderation. Current medications include aspirin and lisinopril. He appears healthy. His temperature is 36.9°C (98.4°F), pulse is 73/min, respirations are 12/min, and blood pressure is 142/92 mmHg. Examination shows decreased pedal pulses bilaterally. Ankle jerk and patellar reflexes are absent bilaterally. Sensation to light touch, pinprick, and proprioception is intact bilaterally. Muscle strength is 5/5 bilaterally. He describes the town he grew up in with detail but only recalls one of three words after 5 minutes. Which of the following is the most appropriate next step in management for these findings?

A 13-year-old girl is brought to the physician by her mother because of a 1-month history of abnormal movements of her muscles that she cannot control. She has a younger brother with cognitive disabilities and epilepsy. Examination shows frequent, brief, involuntary contractions of the muscle groups of the upper arms, legs, and face that can be triggered by touch. An EEG shows generalized epileptiform activity. A trichrome stain of a skeletal muscle biopsy specimen shows muscle fibers with peripheral red inclusions that disrupt the normal fiber contour. Which of the following is the most likely underlying mechanism of the patient's symptoms?

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 55-year-old man is brought to the emergency department by ambulance from a long term nursing facility complaining of severe shortness of breath. He suffers from amyotrophic lateral sclerosis and lives at the nursing home full time. He has had the disease for 2 years and it has been getting harder to breath over the last month. He is placed on a rebreather mask and responds to questions while gasping for air. He denies cough or any other upper respiratory symptoms and denies a history of cardiovascular or respiratory disease. The blood pressure is 132/70 mm Hg, the heart rate is 98/min, the respiratory rate is 40/min, and the temperature is 37.6°C (99.7°F). During the physical exam, he begs to be placed in a sitting position. After he is repositioned his breathing improves a great deal. On physical examination, his respiratory movements are shallow and labored with paradoxical inward movement of his abdomen during inspiration. Auscultation of the chest reveals a lack of breath sounds in the lower lung bilaterally. At present, which of the following muscles is most important for inspiration in the patient?

A 46-year-old man comes to the physician because of a 2-month history of hoarseness and drooling. Initially, he had difficulty swallowing solid food, but now he has difficulty swallowing foods like oatmeal as well. During this period, he also developed weakness in both arms and has had an 8.2 kg (18 lb) weight loss. He appears ill. His vital signs are within normal limits. Examination shows tongue atrophy and pooled oral secretions. There is diffuse muscle atrophy in all extremities. Deep tendon reflexes are 3+ in all extremities. Sensation to pinprick, light touch, and vibration is intact. An esophagogastroduodenoscopy shows no abnormalities. Which of the following is the most likely cause of this patient's symptoms?

In which of the following pathological states would the oxygen content of the trachea resemble the oxygen content in the affected alveoli?