MCQ Book Questions

Q60922. A 30-year-old woman suffers massive trauma in an automobile accident and expires 4 days later of respiratory insuffi ciency. A horizontal section of the patient’s brain at autopsy reveals numerous petechiae scattered throughout the white matter. Which of the following is the most likely explanation for this pathologic fi nding?

Q60923. A 45-year-old man with AIDS is admitted to the hospital with a productive cough, fever, and night sweats. An X-ray fi lm of the chest shows an ill-defi ned area of consolidation at the periphery of the right middle lobe and mediastinal lymphade- nopathy. A sputum culture grows acid-fast bacilli. The patient develops severe headache and neck rigidity. Which of the following brain areas is most likely affected by this patient’s infection?

Q60924. A 65-year-old homeless man is found in the street and is brought to the emergency room with severe lethargy. He is treated with intravenous fl uids but lapses into a coma and expires. Examination of the brainstem at autopsy shows a soft lesion in the tegmentum of the pons. A section stained for myelin with luxol fast blue is shown in the image. Which of the following is associated with this disorder?

Q60925. A 79-year-old man presents to the emergency room with severe right-sided weakness. He has noticed increasing dif- fi culty using his right hand over the past several months and now walks with great diffi culty. His past medical history is sig- nifi cant for colon cancer that was resected 5 years ago. He has poorly controlled hypertension and admits to smoking two packs of cigarettes a day for the past 50 years. A CT scan of the brain reveals a discrete globoid lesion in the frontal lobe with a prominent halo of edema. A CT-guided biopsy reveals neoplastic cells. Which of the following is the most likely diagnosis?

Q60926. A 45-year-old man presents with weakness and wasting of the muscles of his right hand for 8 months. Physical examina- tion shows fasciculations of the hand. The patient’s speech is impaired, and 6 years later, he dies of respiratory insuffi ciency. Autopsy shows atrophy of ventral roots in the spinal cord. Which of the following is the most likely diagnosis?

Q60927. A 6-month-old girl with metachromatic leukodystrophy (MLD) fails to thrive and dies of respiratory insuffi ciency. Histologic examination of the child’s brain at autopsy shows marked accumulation of metachromatic material in the white matter and prominent astrogliosis. Laboratory studies confi rm an accumulation of cerebroside. This patient most likely suf- fered from an inborn error of metabolism, characterized by a defi ciency of which of the following enzymes?

Q60928. A 5-year-old girl exhibits a progressive decline in motor and sensory functions and is quickly reduced to a vegetative state. MRI reveals confl uent, bilaterally symmetric, demy- elination. At autopsy, the brain shows gliosis and perivas- cular infi ltrates of lymphocytes. Laboratory studies disclose high levels of saturated very long–chain fatty acids in tis- sues and body fl uids. This patient’s leukodystrophy is most likely caused by an inborn error in the function of what cell component?

Q60929. An 8-month-old boy exhibits severe motor, sensory, and cognitive impairments. Brain biopsy shows a disease of white matter characterized by the accumulation of “globoid cells.” Biochemical studies reveal an absence of galactoce- rebroside b-galactosidase activity. What is the appropriate diagnosis?

Q60930. A 70-year-old man with a history of senile dementia and a recent myocardial infarct dies of multiple organ system failure following occlusion of the superior mesenteric artery. Exami- nation of the patient’s brain at autopsy reveals aneurysmal dilation of the basilar artery (shown in the image). Which of the following is the most common complication of this patho- logic fi nding?

Q60931. A 55-year-old man is brought to the emergency room after a near-drowning accident while boating. The patient has no pulse when the paramedics arrive, but he is resuscitated. The patient never regains consciousness and expires 3 days later. Examination of the brain at autopsy reveals a watershed zone of infarction in the left cerebral hemisphere. Which of the fol- lowing best describes the pathogenesis of this infarct?

Q60932. A 2-year-old boy is brought to the physician by his parents, who complain that their son continually loses his balance. They also report that his speech seems more slurred. Physical examination confi rms the truncal ataxia and wide-based gait. The child appears lethargic, and there is bobbing of the head while he is sitting. Muscle tone is normal. This patient may have a midline tumor in which anatomic portion of the brain?

Q60933. A lumbar puncture is performed in the patient described in Question 63, and neoplastic cells are found. A suboccipital craniotomy is performed, and a tumor is resected. Microscopic examination of the surgical specimen would most likely reveal which of the following histologic patterns?

Q60934. A 24-year-old woman presents with a 4-month history of head- aches and unsteadiness in walking. She reports a tendency to fall to the right and a loss of coordinated movements in her right hand and leg. Her father and paternal aunt died of renal cell carcinoma. A paternal grandfather had a history of spinal cord tumors, and her sister is seeing an ophthalmologist for “retinal angiomas.” On examination, the woman has a wide- based gait. She is unable to stand on her right leg and has inten- tional tremor and dysdiadokinesia of the right upper extremity. MRI reveals a right-sided parasagittal tumor of the cerebellum. A biopsy of the lesion demonstrates a hemangioblastoma. Which of the following is the most likely diagnosis?

Q60935. A 65-year-old woman with a history of breast cancer and a recent melanoma presents to the emergency room following a tonic-clonic seizure. Blood chemistry values are within nor- mal limits. There is no history of drug or alcohol use. MRI of the brain shows bilateral cerebral edema and a cystic, frontal lobe lesion. Frozen section obtained from a CT-guided biopsy reveals a hemorrhagic nodule of neoplastic cells. Immunohis- tochemical stains for which of the following antigens would be most helpful in making your diagnosis defi nitive for melanoma?

Q60936. An 8-year-old girl is brought to the physician by her parents, who express concerns about their daughters’ academic per- formance and recent changes in behavior. Her vital signs are normal. Neurologic examination reveals motor and sensory impairments. Lumbar puncture shows no biochemical abnor- malities. At autopsy, the brain shows prominent intranuclear inclusions in neurons and oligodendroglia, marked gliosis in gray and white matter, and demyelination. PCR analysis of the brain tissue shows the presence of a defective form of the measles virus. Which of the following is the appropriate diagnosis?

Q60937. A 36-year-old woman with inoperable brain cancer lapses into a coma and dies of cardiorespiratory failure. A horizontal sec- tion of the patient’s brain at autopsy is shown in the image. Dilation of the ventricular system in this patient was most likely caused by obstruction at which of the following ana- tomic locations?

Q60938. A 60-year-old man is brought to the emergency room in a coma. Physical examination reveals an emaciated man with a distended abdomen, jaundice, ascites, and a slightly enlarged liver and spleen. Laboratory studies show elevated levels of blood ammonia. A liver biopsy demonstrates cirrhosis. Histo- logic examination of brain tissue from this patient would most likely show prominent changes in the nuclei of which of the following cell types?

Q60939. A 50-year-old man presents with a 5-month history of severe headaches. Vital signs and CBC are normal. Imaging studies demonstrate a mass in the fourth ventricle and hydrocephalus. The results of a CT-guided biopsy are shown in the image. What is the appropriate diagnosis for this patient’s malignant neoplasm?

Q60940. A 45-year-old woman is brought to the emergency room after experiencing a generalized seizure. An X-ray fi lm of the skull reveals a lytic bone mass. A CBC is normal. A portion of the skull and the adherent mass are removed. Microscopic exami- nation of the surgical specimen is shown in the image. What is the appropriate diagnosis?

Q60941. A 68-year-old man presents with a 2-week history of tonic-clonic seizures that initially involve his left arm but have more recently progressed to involve his left leg. The seizures are accompanied by muscle weakness but no other neurologic signs. The cranial nerves are intact, and the Babinski sign is present. A CT scan reveals a mass in the left cerebral hemi- sphere. A left frontoparietal craniotomy is performed. Histo- logic examination of the brain biopsy is shown in the image. Which of the following is the appropriate diagnosis?