1.  Which clinical signs would you expect in a 53-yearold man with gait ataxia and these MRI findings (see Figure XI-12)?

A. Gait instability, urinary incontinence, dementia

B. Hypertension, tachycardia, diaphoresis

C. Migraine headache, limb weakness, breathing difficulties

D. Scanning speech, oscillatory tremor of the head, Nystagmus

The answer is D. (Chap. 368) This MRI shows cerebellar atrophy consistent with the diagnosis of spinocerebellar ataxia (SCA). The SCAs are a group of autosomal dominant diseases. SCA1, previously known as olivopontocerebellar atrophy, is a disease of early or middle adult life. Patients develop cerebellar ataxia of the trunk and limbs with impair ment of equilibrium and gait, scanning speech, nystagmus, and oscillatory tremor of the head and trunk. There may also be mild dementia. Cerebellar and brainstem atrophy are evident on MRI. Migraine headache, limb weakness, and breathing difficulties are nonspecific but may be seen in serotonin syndrome or alcohol withdrawal. Gait instability, urinary incontinence, and dementia constitute the clinical triad for normal-pressure hydrocephalus, which does not have cerebellar atrophy on MRI. Hypertension, tachycardia, and diaphoresis may be seen in a patient with an Arnold-Chiari malformation. MRI will often show abnormalities in the base of the skull.

2.  On the neurologic consultation service, you are asked to evaluate a patient with mesial temporal lobe epilepsy syndrome. The patient has a history of intractable complex partial seizures that rarely generalize. Her seizures often begin with an aura and commonly manifest as behavioral arrests, complex automatisms, and unilateral posturing. MRI findings include small temporal lobes and a small hippocampus with increased signal on T2- weighted sequences. Which of these additional historic factors are also likely to be present in this patient?

A. History of febrile seizures

B. Hypothyroidism

C. Neurofibromas

D. Recurring genital ulcers

E. Type 2 diabetes mellitus

The answer is A. (Chap. 363) Complex partial seizures are characterized by focal seizure activity plus impairment of the patient’s ability to maintain contact with the environment. Mesial temporal lobe epilepsy is the most common syndrome associated with complex partial seizures. Patients are unable to respond to verbal or visual commands during the seizure and they often manifest complex automatisms or complex posturing. An aura is common before the seizures. There is postictal memory loss or disorientation. Patients often have a history of febrile seizures or a family history of seizures. MRI will show hippocampal sclerosis, a small temporal lobe, or enlarged temporal horn. Hypothyroidism, herpes virus infection, diabetes, and tuberous sclerosis are not associated with mesial temporal lobe epilepsy.

3.  A 54-year-old man has been hospitalized following a myocardial infarction. He has a history of hypertension, hypertriglyceridemia, obesity, mild renal insufficiency and diet-controlled diabetes. His condition is improving, and on the third day of admission his serum urate is elevated at 8.8 mg/dL. He denies any joint complaints and cannot recall ever having symptoms compatible with gout. His serum creatinine is 1.5 mg/dL, which is close to his baseline over the past 3 years. In regard to this patient’s hyperuricemia, which of the following is true?

A. >70% of hospitalized patients will have increased serum urate levels.

B. His hyperuricemia is unrelated to his heart disease.

C. His renal disease is likely caused by his increased serum urate levels.

D. No treatment is needed.

E. This patient should be discharged on low-dose allopurinol

The answer is D. (Chap. 353) Hyperuricemia is present in 5% of the population and in up to 25% of hospitalized patients. The vast majority are at no clinical risk. Hyperuricemia is considered a component of metabolic syndrome; however, this is not an indication to treat elevated urate levels. Instead, an aggressive management strategy to improve lipid levels, diabetic control, and other cardiovascular risk factors should be implemented. This patient has multiple reasons for renal insufficiency. His asymptomatic hyperuricemia is not one of them; structural kidney damage and stone formation only occur with symptomatic hyperuricemia. Treating his urate level will not improve his kidney function nor prevent future stone formation. It is important to remember that hyperuricemia alone does not represent a disease and is not by itself an indication for treatment.

4. All of the following statements regarding hypoglycemia in diabetes mellitus are true except

A. Individuals with type 2 diabetes mellitus experience less hypoglycemia than those with type 1 diabetes mellitus.

B. Recurrent episodes of hypoglycemia predispose to the development of autonomic failure with defective glucose counterregulation and hypoglycemia unawareness.

C. The average person with type 1 diabetes mellitus has two episodes of symptomatic hypoglycemia weekly.

D. Thiazolidinediones and metformin cause hypoglycemia more frequently than sulfonylureas.

E. From 2–4% of deaths in type 1 diabetes mellitus are directly attributable to hypoglycemia.

The answer is D. (Chap. 339) The most common cause of hypoglycemia is related to the treatment of diabetes mellitus. Individuals with type 1 diabetes mellitus (T1DM) have more symptomatic hypoglycemia than individuals with type 2 diabetes mellitus (T2DM). On average, those with T1DM experience two episodes of symptomatic hypoglycemia weekly; and at least once yearly, individuals with T1DM will have a severe episode of hypoglycemia that is at least temporarily disabling. It is estimated that 2–4% of individuals with T1DM will die from hypoglycemia. In addition, recurrent episodes of hypoglycemia in T1DM contribute to the development of hypoglycemia-associated autonomic failure. Clinically, this is manifested as hypoglycemia unawareness and defective glucose counterregulation, with lack of glucagon and epinephrine secretion as glucose levels fall. Individuals with T2DM are less likely to develop hypoglycemia. Medications that are associated with hypoglycemia in T2DM are insulin and insulin secretagogues, such as sulfonylureas. Metformin, thiazolidinediones, α-glucosidase inhibitors, glucagon- like peptide-1 receptor agonists, and dipeptidyl peptidase-IV inhibitors do not cause hypoglycemia.

5. A 27-year-old female with SLE is in remission; current treatment consists of azathioprine 75 mg/d and prednisone 5 mg/d. Last year she had a life-threatening exacerbation of her disease. She now strongly desires to become pregnant. Which of the following is the least appropriate action to take?

A. Advise her that the risk of spontaneous abortion is high.

B. Warn her that exacerbations can occur in the first trimester and in the postpartum period.

C. Tell her it is unlikely that a newborn will have lupus.

D. Advise her that fetal loss rates are higher if anticardiolipin antibodies are detected in her serum.

E. Stop the prednisone just before she attempts to become pregnant.

The answer is E. (Chap. 313) Although most clinicians believe that females with SLE should not become pregnant if they have active disease or advanced renal or cardiac disease, the presence of SLE itself is not an absolute contraindication to pregnancy. The outcome of pregnancy is best for females who are in remission at the time of conception. Even in females with quiescent disease, exacerbations may occur (usually in the first trimester and the immediate postpartum period), and 25 to 40% of these pregnancies end in spontaneous abortion. Fetal loss rates are higher in patients with lupus anticoagulant or anticardiolipin antibodies. Flare-ups should be anticipated and vigorously treated with steroids. Steroids given throughout pregnancy also usually have no adverse effects on the child. In this case, the fact that the female had a life-threatening bout of disease a year ago would argue against stopping her drugs at this time. Neonatal lupus, which is manifested by thrombocytopenia, rash, and heart block, is rare but can occur when mothers have anti-Ro antibodies.

6. In the case vignette presented above, which of the following factors at presentation predicts a poor outcome and increased risk of death in acute pancreatitis?

A. Body mass index (BMI) >25 kg/m2

B. Hematocrit ≥40%

C. Lipase >1000 IU/L

D. PaO2 <60 mmHg

E. WBC count >10,000/μL

The answer is D. (Chap. 307) Several risk factors have been identified that predict an increased risk of death in acute pancreatitis. Pancreatic necrosis and evidence of multiorgan failure have been the strongest predictors of death in multiple case series. This includes the presence of shock, hypoxemia (PaO2 <60 mmHg), renal failure (creatinine >2.0mg/dL), hemoconcentration with a hematocrit >44%, and gastrointestinal bleeding. In addition, other clinical factors including obesity (BMI >30 kg/m2) and age >70 predict poorer outcomes. Values of amylase and lipase have not been shown to predict the course of acute pancreatitis, and amylase can be spuriously elevated in the presence of a pH <7.32. The Ranson criteria include a variety of biochemical markers at admission and at 48 h that predict outcome in acute pancreatitis. This patient does not meet any of the Ranson criteria at admission (age >55, WBC count >16,000/μL, glucose >200 mg/dL, AST >250 U/L, LDH >350 U/L). A reevaluation at 48 h would be necessary to use Ranson criteria to assess the patient’s risk of death to see if any of the six additional criteria had been fulfilled.

7. All of the following necessitate sending bacterial stool cultures in patients with diarrhea for 2 days severe enough to keep them home from work except

A. age >75

B. bloody stools

C. dehydration

D. recent lung transplantation

E. temperature >38.5°C

The answer is C. (Chap. 40) Most causes of acute diarrhea are infectious. Dehydration is a feature of all infectious diarrheas and does not suggest bacterial etiology. Fever and bloody diarrhea are more suggestive. Immunocompromised hosts and the elderly are at greater risk for developing bacteremia and sepsis with certain pathogens, and they also may be less likely to have symptoms suggesting a bacterial pathogen. Stool cultures are typically sent in these populations unless symptoms are mild. See Figure VIII-7.

8. The patient in the preceding scenario is found to have a serum calcium of 12.1 mg/dL. Of the following interventions, what therapy is most appropriate in this patient?

A. Glucocorticoids

B. Intravenous loop diuretic

C. Intravenous phosphate

D. Oral calcitriol

E. Zoledronic acid

The answer is A. (Chap. 47) In sarcoidosis, similar to other granulomatous diseases such as tuberculosis and silicosis, there is increased conversion of 25(OH)D to the potent 1, 25(OH)2D. 1,25(OH)2D enhances intestinal calcium absorption, resulting in hypercalcemia and suppressed parathyroid hormone. Glucocorticoids decrease 1,25(OH)2D production. Initial treatment for this patient should include IV fluids to restore extracellular fluid volume. Only after volume has been restored should loop diuretics be used to decrease serum calcium. Zoledronic acid is indicated if there is increased calcium mobilization from bone, as in malignancy or severe hyperparathyroidism. Intravenous phosphate is not indicated as it chelates calcium and may deposit in tissue and cause extensive organ damage if the calcium-phosphate product is >65. The mechanism of the hypercalcemia of sarcoidosis is related to excess vitamin D, therefore calcitriol would be contraindicated.

9. A 23-year-old hospital worker is evaluated for a known contact with a patient with active tuberculosis. One year ago his intermediate-strength PPD had 3 mm of induration; now it has 13 mm of induration at 48h. He has no significant past medical history and is on no medications. Subsequent management should include

A. chest radiography

B. isoniazid 300 mg/d for 3 months

C. measurement of baseline liver function tests

D. measurement of liver function tests every 3 months

E. repeated intermediate-strength PPD testing in 2 weeks

The answer is A. (Chap. 158) This patient has evidence of recent tuberculosis infection with the change from a negative to a positive PPD. A chest radiogram should be performed to rule out active disease and the presence of latent disease. If there is no abnormality, isoniazid should be prescribed to prevent subsequent development of active disease. The optimal duration of therapy is 6 to 12 months, with most recommending 9 months to achieve maximal protection from active disease. The major complication of this therapy is hepatitis. Isoniazid should not be given to patients with active liver disease. All these patients should be educated about the signs or symptoms of hepatitis and should be instructed to discontinue the medication if those symptoms develop. Patients should be questioned about symptoms monthly. Baseline liver function tests need be obtained only in patients with a history of liver disease or daily alcohol use. Serial measurement of liver function is not necessary in the absence of a history of liver disease or alcohol use.

10. In the intensive care unit, you are caring for a 36-yearold man with a cocaine overdose. He has pyrexia, tachycardia, and hypertensive urgency. He begins to have brief episodes of ventricular tachycardia but is awake but disoriented. Over the next hour, his ventricular tachycardia becomes more frequent and lasts longer each time. What is the appropriate management strategy for his arrhythmia?

A. Intravenous diazepam

B. Intravenous hydralazine

C. Intravenous norepinephrine

D. Intravenous propranolol

The answer is D. (Chap. 389; RL Lange: N Engl J Med 345:351, 2001.) Cocaine overdose is a potentially lethal condition that should be managed in the intensive care unit setting. These patients are in a hyperadrenergic state characterized by hypertension, tachycardia, tonic-clonic seizures, dyspnea and ventricular arrhythmias. Ventricular arrhythmias have been managed with IV nonselective beta-receptor blockers such as propranolol. There is concern with giving beta-blockers in patients with cocaine-induced chest pain or myocardial ischemia because of the potential for unopposed alpha activity provoking coronary vasospasm. Calcium channel blockers are often used in patients with cocaine intoxication and potential coronary ischemia to avoid this effect. Tonic-clonic seizures have been managed with IV diazepam infusions, but it would not benefit the ventricular ectopy. Hydralazine may manage the hypertension but would have no effect on the ventricular arrhythmia and might cause a reflex tachycardia. Cardioversion is not indicated for this patient who is in nonsustained ventricular tachycardia. Also, without addressing the underlying disorder prompting the arrhythmia (i.e., increased norepinephrine in the presynaptic space), the tachycardia is likely to recur. Norepinephrine would be contraindicated as it would exacerbate the hyperadrenergic state.

11. All the following disorders may be associated with thoracic aortic aneurysm except

A. osteogenesis imperfecta

B. Takayasu’s arteritis

C. Ehlers-Danlos syndrome

D. ankylosing spondylitis

E. Klinefelter’s syndrome

The answer is E. (Chaps. 230 and 242) Aortic aneurysm results from numerous mechanisms. The vast majority are associated with atherosclerosis. The risk factors for atherosclerosis (hypertension, hypercholesterolemia, etc.) are also risk factors for aneurysm formation. It is unclear if atherosclerosis is the primary cause or a result of the same pathophysiologic mechanisms that lead to dilatation. Other etiologies include congenital causes. Marfan’s syndrome and Ehlers-Danlos syndrome are the most frequently noted. However, there is also an association with osteogenesis imperfecta. Turner’s syndrome is associated with coarctation of the aorta. Repair of coarctation may predispose to later dilation and aneurysm formation. Klinefelter’s syndrome, however, is not associated with aneurysm formation. Chronic infectious causes include syphilis and mycotic aneurysm from bacterial endocarditis. Chronic inflammatory states such as Takayasu’s arteritis, giant cell arteritis, and seronegative spondyloarthropathies such as Reiter’s syndrome and ankylosing spondylitis are also associated with aneurysms.

12. Which of the following disorders is not associated with ventricular tachycardia as a cause of syncope?

A. Hypertrophic obstructive cardiomyopathy

B. Prior myocardial infarction

C. Atrial myxoma

D. Aortic valvular stenosis

E. Congenital long QT syndrome

The answer is C. (Chap. 22) Although ventricular tachycardia is classically associated with ischemic heart disease, in which scarred myocardium provides a substrate for reentrant tachyarrhythmias, other cardiac lesions put a patient at risk for ventricular tachycardia. Notably, hypertrophic obstructive cardiomyopathy, aortic stenosis, and long QT syndrome carry an increased risk for ventricular tachycardia. Atrial myxoma, which can cause syncope by obstructing blood flow with resultant decreased cardiac output, is not associated with ventricular tachycardia.

13. Fall risks in the elderly include all of the following except

A. creatinine clearance <65 mL/min

B. diabetes mellitus

C. fear of falling

D. history of falls

E. hypertension

F. psychotropic medications

The answer is E. (Chap. 9) Fall rates increase with age and have substantial effect on mortality and morbidity. Some 3–5% of falls result in fracture, and falls are an independent risk factor for nursing home placement. All older adults should have at least annual fall risk assessment and be asked about falls during clinic visits. Fall prevention necessitates a multidisciplinary approach including management of medical conditions associated with falls, limitation of psychotropic medicines (especially benzodiazepines), frequent visual examinations, interventions such as tai-chi geared towards stabilizing gait, and close examination of circumstances associated with past falls.

14. Which cardiac valvular disorder is the most likely to cause death during pregnancy?

A. Aortic regurgitation

B. Aortic stenosis

C. Mitral regurgitation

D. Mitral stenosis

E. Tricuspid regurgitation

The answer is D. (Chap. 7) Mitral stenosis is associated with flash pulmonary edema, atrial arrhythmias, and risk of maternal death. The risk is likely related to the increase in cardiac output and circulating blood volume during pregnancy. Sudden death due to arrhythmia or pulmonary hypertension may occur. During delivery, patients with mitral stenosis should be managed with careful heart rate control. Balloon valvuloplasty may be performed during pregnancy. The decrease in systemic vascular resistance during pregnancy makes mitral, tricuspid, and aortic regurgitation generally well tolerated because heart failure is not likely. If aortic stenosis is severe, balloon valvuloplasty may be necessary.

15. A 43-year-old man with alcoholic liver disease complains of dyspnea upon sitting up. Physical examination is notable for chest spider angiomas and palmar erythema. His arterial oxygen saturations fall from 96% to 88% upon transition from lying to sitting. His lung fields are clear and heart sounds are crisp. Abdominal examination is notable for a palpable nodular liver edge but no fluid wave or shifting dullness. He has 1+ lower extremity edema. What is the most likely cause of his dyspnea?

A. Chronic thromboembolic disease

B. Congestive heart failure

C. Pulmonary arteriovenous fistula

D. Portal hypertension

E. Ventricular septal defect

The answer is C. (Chap. 35) Cirrhotic patients are at risk of developing pulmonary arteriovenous fistulas. These, as well as portopulmonary shunts, cause platypnea and orthodeoxia (dyspnea and desaturation with sitting up). The fistulas, which are preferentially at the base of the lungs, increase the right-to-left shunting (and therefore hypoxemia) when upright. In the supine position, the apex of the lung is better perfused and the hypoxemia improves. The oxygen desaturation in the upright position causes the platypnea. Congenital pulmonary arteriovenous malformations may also cause platypnea and orthodeoxia. Ventricular septal defects will not cause hypoxemia until they develop right-toleft shunting.

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