1. Which of the following class of medicines has been linked to the occurrence of hip fractures in the elderly?

A. Benzodiazepines

B. Opiates

C. Angiotensin-converting enzyme inhibitors

D. Beta blockers

E. Atypical antipsychotics

The answer is A. (Chap. 5) In population surveys of noninstitutionalized elderly, up to 10% had at least one adverse drug reaction in the prior year. Adverse drug reactions are common in the elderly and are related to altered drug sensitivity, impaired renal or hepatic clearance, impaired homeostatic mechanisms, and drug interactions. Long half-life benzodiazepines are linked to the increased occurrence of hip fractures in the elderly. The association may be due to the increased risk of falling (related to sedation) in a population with a high prevalence of osteoporosis. This association may also be true for other drugs with sedative properties such as opioids or antipsychotics. Exaggerated responses to cardiovascular drugs such as ACE inhibitors may occur because of a blunted vasoconstrictor or chronotropic response to reduced blood pressure. Conversely, elderly patients often display decreased sensitivity to beta blockers.

2. Which of the following conditions is associated with increased susceptibility to heat stroke in the elderly?

A. A heat wave

B. Antiparkinsonian therapy

C. Bedridden status

D. Diuretic therapy

E. All of the above

The answer is E. (Chap. 17) The elderly and the very young are at highest risk of nonexertional heat stroke. Environmental stress (heat wave) is the most common precipitating factor, particularly in the bedridden or for those living in poorly ventilated or non air-conditioned conditions. Medications such as antiparkinson treatment, diuretics, or anticholinergic therapy increase the risk of heat stroke.

3. Which of the following is the best indicator of prognosis and longevity in a geriatric patient?

A. Functional status

B. Life span of first-degree relatives

C. Marital status

D. Number of medical comorbidities

E. Socioeconomic status

The answer is A. (Chap. 9) Functional status, as defined by a patient’s ability to provide for his or her own daily needs, is the most important indicator for prognosis. A decline in functional status should prompt a search for medical illness, dementia, change in social support, or depression. Screening for functional status should include assessment of activities of daily living, gait and balance, cognition, vision, hearing, and dental and nutritional health.

4. An 86-year-old woman with chronic obstructive pulmonary disease (COPD), congestive heart failure, and insulin-requiring type 2 diabetes mellitus is admitted to the intensive care unit with an exacerbation of her COPD. She is intubated and treated with glucocorticoids and nebulized albuterol. She is also continued on her glargine insulin, aspirin, pravastatin, furosemide, enalapril, and metoprolol. On hospital day 8, parenteral nutrition is begun via catheter in the subclavian vein. Her insulin requirements increase on hospital day 9 due to episodes of hyperglycemia. On hospital day 10, she develops rales and an increasing oxygen requirement. A chest radiograph shows bilateral pulmonary edema. Laboratory data show hypokalemia, hypomagnesemia, and hypophosphatemia and a normal creatinine. Her weight has increased by 3 kg since admission. Urine sodium is <10 meq/dL. All of the following changes in her nutritional regimen will improve her volume status except

A. combination of glucose and fat in the parenteral nutrition mixture

B. decreasing the sodium content of the mixture to <40 meq per day

C. increasing the protein content of the parenteral nutrition mixture

D. reducing the overall glucose content

The answer is C. (Chap. 73) The most common metabolic problems related to parenteral nutrition (PN) are fluid overload and hyperglycemia. Hypertonic dextrose stimulates a much higher insulin level than normal feeding, which is evident on hospital day 9 in this scenario. Hyperinsulinemia stimulates antinatriuretic and antidiuretic hormone, which leads to sodium and fluid retention as well as increased intracellular transport of potassium, magnesium, and phosphorus. It is not uncommon to see an increase in weight and a low urine sodium in patients with normal renal function. Providing sodium in limited amounts of 40 meq/day and the use of both glucose and fat in the PN mixture will help reduce fluid retention. Reducing the overall glucose content will also abate the need for higher insulin level. The fluid retention in this scenario is not mediated by low protein levels.

5. A healthy 62-year-old woman returns to your clinic after undergoing routine colonoscopy. Findings included two 1.3-cm sessile (flat-based), villous adenomas in her ascending colon that were removed during the procedure. What is the next step in management?

A. Colonoscopy in 3 months

B. Colonoscopy in 3 years

C. Colonoscopy in 10 years

D. CT scan of the abdomen

E. Partial colectomy

F. Reassurance

The answer is B. (Chap. 87) Most colorectal cancers arise from adenomatous polyps. Only adenomas are premalignant, and only a minority of these lesions becomes malignant. Most polyps are asymptomatic, causing occult bleeding in <5% of patients. Sessile (flat-based) polyps are more likely to become malignant than pedunculated (stalked) polyps. Histologically, villous adenomas are more likely to become malignant than tubular adenomas. The risk of containing invasive carcinoma in the polyp increases with size with <2% in polyps <1.5 cm, 2–10% in polyps 1.5–2.5 cm, and 10% in polyps >2. 5 cm. This patient had two polyps that were high-risk based on histology (villous) and appearance (sessile) but only moderate risk by size (<1.5 cm). Polyps, particularly those >2.5 cm in size, sometimes contain cancer cells but usually progress to cancer quite slowly over a ~5-year period. Patients with adenomatous polyps should have a follow-up colonoscopy or radiographic study in 3 years. If no polyps are found on initial study, the test (endoscopic or radiographic) should be repeated in 10 years. CT scan is only warranted for staging if there is a diagnosis of colon cancer, not for the presence of polyps alone.

6. An 18-year-old man presents with a firm, nontender lesion around his anal orifice. The lesion is about 1.5 cm in diameter and has a cartilaginous feel on clinical examination. The patient reports that it has progressed to this stage from a small papule. It is not tender. He reports recent unprotected anal intercourse. Bacterial culture of the lesion is negative. A rapid plasmin regain (RPR) test is also negative. Therapeutic interventions should include

A. IM ceftriaxone, 1g

B. IM penicillin G benzathine, 2.4 million U

C. oral acyclovir, 200 mg 5 times per day

D. observation

E. surgical resection with biopsy

The answer is B. (Chap. 162) The patient’s clinical examination is consistent with primary syphilis and he should receive appropriate therapy. In primary syphilis, 25% of patients will have negative nontreponemal tests for syphilis (RPR or VDRL). A single dose of long-acting benzathine penicillin is the recommended treatment for primary, secondary, and early latent syphilis. Ceftriaxone is the treatment of choice for gonorrhea, but this lesion is not consistent with that diagnosis. Ceftriaxone given daily for 7–10 days is an alternative treatment for primary and secondary syphilis. Acyclovir is the drug of choice for genital herpes. Herpetic lesions are classically multiple and painful. Observation is not an option because the chancre will resolve spontaneously without treatment and the patient will remain infected and infectious.

7. You are seeing a 71-year-old patient with tachycardiabradycardia syndrome in follow-up. She had a single-lead ventricular pacemaker implanted 2 years ago and has no new complaints. Past medical history also includes an old stroke with mild residual left hand weakness and diabetes. Her last transthoracic echocardiogram showed a left ventricular ejection fraction of 35–40% but no valvular abnormalities. The left atrium is mildly enlarged. Her medical regimen includes aspirin, metformin, metoprolol, lisinopril, lasix, and dipyridamole. What intervention, if any, should be considered for this patient at this time?

A. Anticoagulation

B. Cardiac catheterization

C. Discontinuation of dipyridamole

D. None, as she has no new complaints

The answer is A. (Chap. 225) One-third of patients with sinoatrial node dysfunction will develop supraventricular tachycardia, usually atrial fibrillation or atrial flutter. Patients with the tachycardia-bradycardia variant of sick sinus syndrome are at risk for thromboembolism. Those at greatest risk include age >65 years, prior history of stroke, valvular heart disease, left ventricular dysfunction, or atrial enlargement. These patients should be treated with anticoagulants. There is no reason to discontinue dypyridamole at this time as she is complaining of no side effects, and the absence of angina argues against the need for cardiac catheterization.

8. A 60-year-old male is seen in the clinic for counseling about asbestos exposure. He is well and has no symptoms. He also has hypertension, for which he takes hydrochlorothiazide. The patient smokes one pack of cigarettes a day but has no other habits. He is currently retired but worked for 30 years as a pipefitter and says he was around “lots” of asbestos, often without wearing a mask or other protective devices. Physical examination is normal except for nicotine stains on the left second and third fingers. Chest radiography shows pleural plaques but no other changes. Pulmonary function tests, including lung volumes, are normal. Which of the following statements should be made to this patient?

A. He must quit smoking immediately as his risk of emphysema is higher than that of other smokers because of asbestos exposure.

B. He does not have asbestosis.

C. His risk of mesothelioma is higher than that of other patients with asbestos exposure because he has a history of tobacco use.

D. He has no evidence of asbestos exposure on chest radiography.

E. He should undergo biannual chest radiography screening for lung cancer.

The answer is B. (Chap. 250) Asbestos was a commonly used insulating material from the 1940s to the mid-1970s, after which it was largely replaced by fiberglass and slag wool. Workers in many occupations had significant exposure and often did not use protective equipment. There are several pulmonary manifestations of asbestos exposure in the lungs, the most important of which are pleural plaques, benign asbestos pleural effusions, asbestosis, lung cancer, and mesothelioma. Pleural plaques, which appear as calcifications or thickening along the parietal pleura, simply suggest exposure and not pulmonary impairment. Benign pleural effusions can occur and are often bloody. They may regress or progress spontaneously. Asbestosis refers to interstitial lung disease, generally with fibrosis, seen in the lower lung fields of a chest radiogram or chest CT and an associated restrictive ventilatory defect. This patient does not have interstitial changes on chest radiography and has no restriction on pulmonary function tests; therefore, he does not have asbestosis. The risk of lung cancer, including squamous cell cancer and adenocarcinoma, is elevated in all patients with asbestos exposure but is amplified further by cigarette smoking. In contrast, mesothelioma risk, though elevated in patients with asbestos exposure, is not increased by cigarette smoking. Interestingly, despite the high risk of malignancies in this group of patients, no benefit has been ascribed to screening techniques, including biannual chest radiograms.

9. Preoperative assessment of a 55-year-old male patient going for coronary angiography shows an estimated glomerular filtration rate of 33 mL/min per 1.73 m2 and poorly controlled diabetes. He is currently on no nephrotoxic medications, and the nephrologist assures you that he does not currently have acute renal failure. The case is due to begin in 4 h, and you would like to prevent contrast nephropathy. Which agent will definitely reduce the risk of contrast nephropathy?

A. Dopamine

B. Fenoldopam

C. Indomethacin

D. N-acetylcysteine

E. Sodium bicarbonate

The answer is E. (Chap. 273) Radiocontrast agents cause renal injury through intrarenal vasoconstriction and through generation of oxygen radicals causing acute tubular necrosis. These medications cause an acute decrease in renal blood flow and glomerular filtration rate. Patients with chronic kidney disease, diabetes mellitus, heart failure, multiple myeloma, and volume depletion are at highest risk of contrast nephropathy. It is clear that hydration with normal saline is an effective measure to prevent contrast nephropathy. Of the other measures mentioned here, only sodium bicarbonate or N-acteylcysteine could be recommended for clinical use to reduce the risk of contrast nephropathy. Dopamine has been proven an ineffective agent to prevent contrast nephropathy. Fenoldopam, a D1-receptor agonist, has been tested in several clinical trials and does not appear to reduce the incidence of contrast nephropathy. Although several small clinical studies have suggested a clinical benefit to the use of N-acetylcysteine, a meta-analysis has been inconclusive, and the medication should be administered well in advance of the procedure. Sodium bicarbonate begun within 1 h of the procedure has shown a significant benefit in a single-center, randomized controlled trial. Due to the time limitations, and based on the evidence, only sodium bicarbonate would be helpful in this patient.

10. Which of the following statements about alcoholic liver disease is not true?

A. Pathologically, alcoholic cirrhosis is often characterized by diffuse fine scarring with small regenerative nodules.

B. The ratio of AST to ALT is often higher than 2.

C. Serum aspartate aminotransferase levels are often greater than 1000 U/L.

D. Concomitant hepatitis C significantly accelerates the development of alcoholic cirrhosis.

E. Serum prothrombin times may be prolonged, but activated partial thromboplastin times are usually not affected.

The answer is C. (Chap. 302) Alcoholic cirrhosis is the most common type of cirrhosis encountered in North America. Unlike some other causes of cirrhosis, pathologically it is characterized by small, fine scarring and small regenerative nodules. Therefore, it sometimes is referred to as micronodular cirrhosis. There is clear evidence that excessive alcohol use in the setting of chronic hepatitis C strongly increases the risk of development of cirrhosis; therefore, screening and appropriate counseling are essential. Ethanol results in proportionally greater inhibition of ALT synthesis than AST synthesis. Therefore, serum AST is usually disproportionately elevated relative to ALT, resulting in a ratio greater than 2. The liver is the site of vitamin K–dependent carboxylation of coagulation factors II, VII, IX, and X. Therefore, with progressive deterioration in liver function, elevations in serum prothrombin time result, as the extrinsic pathway of coagulation is primarily dependent on tissue factor and factor II. The intrinsic pathway contains many other unaffected factors, and the activated partial thromboplastin time is often normal. Unlike the case in acute viral hepatitis, acetaminophen toxicity, and vascular congestion, alcoholic injury to the liver rarely elevates the transaminases above levels in the hundreds. Elevations in the AST above 500 to 600 U/L should prompt a search for alternative or coincident diagnoses.

11. Which of the following proteins does not cause secretion of gastric acid?

A. Acetylcholine

B. Caffeine

C. Gastrin

D. Histamine

E. Somatostatin

The answer is E. (Chap. 287) Gastric parietal cells create hydrochloric acid through a process of oxidative phosphorylation involving the H+-K+-ATPase pump. For each molecule of hydrochloric acid produced, a bicarbonate ion is released into the gastric venous circulation, creating the “bicarbonate tide.” Control of gastric acid secretion is primarily under the control of the parasympathetic system. Postganglionic vagal fibers stimulate muscarinic receptors on parietal cells to increase acid secretion. In addition, cholinergic stimulation increases gastrin release from antral G cells as well as increasing the sensitivity of parietal cells to circulating gastrin. Gastrin is the most potent stimulus of gastric acid secretion and is released from antral G cells in response to cholinergic stimuli. Histamine is also a potent stimulus for gastric acid secretion. It is stored in enterochromaffinlike cells in the oxyntic glands of the stomach. Stimuli for histamine release include gastrin and acetylcholine. Finally, caffeine stimulates gastrin release and thus increases acid secretion. The most important protein produced in the stomach for inhibition of acid secretion is somatostatin. It is produced in the D cells of the antrum, and its release is stimulated by a fall in the gastric pH to less than 3.0. Further inhibition of gastric acid secretion is mediated by intestinal peptides secreted from the duodenum in response to acid pH. These peptides include gastric inhibitory peptide and vasoactive intestinal peptide. Finally, hyperglycemia and hypertonic fluids in the duodenum also inhibit gastric acid secretion through mechanisms that are unknown.

12. A 48-year-old male has a long-standing history of ankylosing spondylitis. His most recent spinal film shows straightening of the lumbar spine, loss of lordosis, and “squaring” of the vertebral bodies. He currently is limited by pain with ambulation that is not improved with nonsteroidal anti-inflammatory medications. Which of the following treatments has been shown to improve symptoms the best at this stage of the illness?

A. Celecoxib

B. Etanercept

C. Prednisone

D. Sulfasalazine

E. Thalidomide

The answer is B. (Chap. 318) Before the introduction of anti-tumor necrosis factor (TNF) therapy, the mainstay of treatment for ankylosing spondylitis was nonsteroidal anti-inflammatory drugs (NSAIDs) and exercise therapy. In 2000, infliximab and etanercept were introduced and since that time have been shown to confer a rapid, profound, and sustained reduction in all clinical and laboratory measures of disease activity. Even patients with long-standing disease and ankylosis show significant improvement in spinal mobility and pain relief. MRI findings in patients treated with these agents also show marked improvement in marrow edema, enthesitis, and joint effusions. The long-term effects of these agents are not known. Other treatments for AS can be used, including NSAIDs and COX-2 inhibitors, to decrease pain, especially in mild cases. An ongoing exercise program is encouraged to maintain posture and range of motion. In patients with more severe pain, sulfasalazine or methotrexate may be added with modest benefit, especially in those with peripheral arthritis. Diverse other agents have been tried, including thalidomide, bisphosphonates, and radium-224. Glucocorticoids have no role in the treatment of this disease.

13. A patient presents with 3 weeks of pain in the lower back. All the following are risk factors for serious causes of spine pathology except

A. age more than 50 years

B. urinary incontinence

C. duration of pain more than 2 weeks

D. bed rest without relief

E. history of intravenous drug use

The answer is C. (Chap. 16) Acute low back pain is defined as pain of less than 3 months’ duration. Most patients with back pain have symptoms that are “mechanical,” such as pain that is worsened by activity and relieved by rest. Initial assessment of all these patients must evaluate for serious causes of spine pathology, such as infection, malignant disease, and trauma. Risk factors include age over 50 years, prior diagnosis of cancer, intravenous drug use, chronic infection such as cystitis or pneumonia, a history of spine trauma, bed rest without relief, duration of pain of more than 1 month, urinary incontinence or nocturia, focal leg weakness or numbness, pain radiating into the leg or legs from the back, pain that increases with standing and is relieved by sitting, and chronic steroid use. Examination findings that raise concern for serious underlying disease include fever, weight loss, a positive straight leg raise, an abdominal or rectal mass, and neurologic examination abnormalities, either motor or sensory.

14. A 45-year-old man is diagnosed with pheochromocytoma after presentation with confusion, marked hypertension to 250/140 mmHg, tachycardia, headaches, and flushing. His fractionated plasma metanephrines show a normetanephrine level of 560 pg/mL and a metanephrine level of 198 pg/mL (normal values: normetanephrine: 18–111 pg/mL; metanephrine: 12–60 pg/mL). CT scanning of the abdomen with IV contrast demonstrates a 3-cm mass in the right adrenal gland. A brain MRI with gadolinium shows edema of the white matter near the parietooccipital junction consistent with reversible posterior leukoencephalopathy. You are asked to consult regarding management. Which of the following statements is true regarding management of pheochromocytoma is this individual?

A. Beta-blockade is absolutely contraindicated for tachycardia even after adequate alpha blockade has been attained.

B. Immediate surgical removal of the mass is indicated, because the patient presented with hypertensive crisis with encephalopathy.

C. Salt and fluid intake should be restricted to prevent further exacerbation of the patient’s hypertension.

D. Treatment with phenoxybenzamine should be started at a high dose (20–30 mg three times daily) to rapidly control blood pressure, and surgery can be undertaken within 24–48 h.

E. Treatment with IV phentolamine is indicated for treatment of the hypertensive crisis. Phenoxybenzamine should be started at a low dose and titrated to the maximum tolerated dose over 2–3 weeks. Surgery should not be planned until the blood pressure is consistently below 160/100 mmHg.

The answer is E. (Chap. 337) Complete removal of the pheochromocytoma is the only therapy that leads to a long-term cure, although 90% of tumors are benign. However, preoperative control of hypertension is necessary to prevent surgical complications and lower mortality. This patient is presenting with encephalopathy in a hypertensive crisis. The hypertension should be managed initially with IV medications to lower the mean arterial pressure by ~20% over the initial 24-h period. Medications that can be used for hypertensive crisis in pheochromocytoma include nitroprusside, nicardipine, and phentolamine. Once the acute hypertensive crisis has resolved, transition to oral -adrenergic blockers is indicated. Phenoxybenzamine is the most commonly used drug and is started at low doses (5–10 mg three times daily) and titrated to the maximum tolerated dose (usually 20–30 mg daily). Once alpha blockers have been initiated, beta blockade can safely be utilized and is particularly indicated for ongoing tachycardia. Liberal salt and fluid intake helps expand plasma volume and treat orthostatic hypotension. Once blood pressure is maintained below 160/100 mmHg with moderate orthostasis, it is safe to proceed to surgery. If blood pressure remains elevated despite treatment with alpha blockade, addition of calcium channel blockers, angiotensin receptor blockers, or angiotensinconverting enzyme inhibitors should be considered. Diuretics should be avoided as they will exacerbate orthostasis.

15. A 78-year-old man with diabetes mellitus presents with fever, headache and altered sensorium. On physical exam his temperature is 40.2°C, heart rate is 103 beats/min, blood pressure is 84/52 mmHg. His neck is stiff and he has photophobia. His cerebrospinal fluid (CSF) examination shows 2100 cells/L, with 100% neutrophils, glucose 10mg/dL, and protein 78 mg/dL. CSF gram stain is negative. Empirical therapy should include which of the following?

A. Amphotericin

B. Dexamethasone after antibiotics

C. Dexamethasone prior to antibiotics

D. Doxycycline

E. Piperacillin/tazobactam

The answer is C. (Chap. 376) The release of bacterial cell wall components after killing by antibiotics may evoke a marked inflammatory cytokine response in the subarachnoid space. This inflammation may lead to increased damage of the blood brain barrier and central nervous system damage. Glucocorticoids can blunt this response by inhibiting tumor necrosis factor and interleukin-1. They work best if administered before antibiotics. Clinical trials have demonstrated that dexamethasone, 10 mg IV administered 20 min before antibiotics, reduced unfavorable outcomes, including death. The dexamethasone was continued for 4 days. The benefits were most striking in pneumococcal meningitis. Because this is the most common cause of meningitis in the elderly, empirical coverage should include this intervention as well. Empirical antibiotics in this case should include a third-generation cephalosporin, vancomycin, and ampicillin. However, dexamethasone may decrease vancomycin penetration into the CSF, so its use should be considered carefully in cases where the most likely organism requires vancomycin coverage.

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