1.       A 32-year-old woman is seeing you because her mother has been diagnosed with osteoporosis. She asks you what type of exercise will help her prevent the development of the disease. According to recommendations, which of the following exercises is most appropriate to help her maintain bone mass?

A. Tennis

B. Swimming

C. Cycling

D. Skating

E. Skiing

The answer is A

EXPLANATION: Weight-bearing activity is known to retard bone loss. While there have been no randomized clinical trials comparing the effect of various activities on bone mass, recommended activities include walking, jogging, weight lifting, aerobics, stair climbing, field sports, racquet sports, court sports, and dancing. Swimming is questionable, as it is not weight-bearing. There is no data on cycling, skating, or skiing.

2.       A 70-year-old male complains of 2 months of low back pain and fatigue. He has developed fever with purulent sputum production. On physical examination, he has pain over several vertebrae and rales at the left base. Laboratory results are as follows:

Hemoglobin: 7 g/dL

MCV: 89 fL (normal 86 to 98)

WBC: 12,000/mL

BUN: 44 mg/dL

Creatinine: 3.2 mg/dL

Ca: 11.5 mg/dL

Chest x-ray: LLL infiltrate

Reticulocyte count: 1%

The definitive diagnosis is best made by which of the following?

A. 24-hour urine protein

B. Bone scan

C. Renal biopsy

D. Rouleaux formation on blood smear

E. Greater than 30% plasma cells in the bone marrow

The answer is E.

EXPLANATION: Multiple myeloma would best explain this patient's presentation. The onset of myeloma is often insidious. Pain caused by bone involvement, anemia, renal insufficiency, and bacterial pneumonia often follow. This patient presented with fatigue and bone pain, then developed bacterial pneumonia probably secondary to Streptococcus pneumoniae, an encapsulated organism for which antibody to the polysaccharide capsule is not adequately produced by the myeloma patient. There is also evidence for renal insufficiency. Hypercalcemia is frequently seen in patients with multiple myeloma and may be life threatening. Definitive diagnosis of multiple myeloma is made by demonstrating greater than 30% plasma cells in the bone marrow. None of the other findings are specific enough for definitive diagnosis. 75% of patients with myeloma will have a monoclonal M spike on serum protein electrophoresis, but 25% will produce primarily Bence-Jones proteins, which, because of their small size, do not accumulate in the serum but are excreted in the urine. Urine protein electrophoresis will identify these patients. Approximately 1% of patients with myeloma will present with a nonsecretory myeloma; the diagnosis can be made only with bone marrow biopsy. The bone scan in myeloma is usually negative. The radionuclide is taken up by osteoblasts, and myeloma is usually a purely osteolytic process. Renal biopsy might show monoclonal protein deposition in the kidney or intratubular casts but would not be the first diagnostic procedure. Rouleaux formation, although characteristic of myeloma, is neither sensitive nor specific.

3.       A 66-year-old diabetic man comes to your office with acute monoarticular arthritis. You suspect gout. Which of the following tests is the most helpful in establishing the diagnosis?

A. Sedimentation rate

B. C-reactive protein

C. Serum uric acid levels

D. Evaluation of joint aspirate

E. Twenty-four-hour urine collection to measure uric acid excretion

The answer is D.

EXPLANATION: An evaluation of the joint aspirate is strongly recommended to establish the diagnosis of gout. It is critical to differentiate gout from infectious arthritis which is a medical emergency, and a joint aspirate will do this rapidly and accurately. The sedimentation rates and C-reactive protein are both nonspecific. Serum uric acid levels can be normal or high in the setting of acute gout. A 24-hour urine collection may help determine the most effective treatment for gout, but is not needed for diagnosis.

4.       A 42-year-old IV drug user presents to the ED with fever, chills, pleuritic chest pain, myalgias, and general malaise. The patient's vitals include a HR of 110 beats per minute, BP of 110/65 mm Hg, RR of 18 breaths per minute, and temperature of 103°F. Physical examination is notable for retinal hemorrhages, petechiae on the conjunctivae and mucus membranes, a faint systolic ejection murmur, and splenomegaly. Which of the following is the most likely diagnosis?

A. Sick sinus syndrome

B. Myocarditis

C. Pericarditis

D. Cardiac tamponade

E. Endocarditis

The answer is E.

EXPLANATION: Symptoms of endocarditis are nonspecific and vary widely, but the most common include fever (85%) and malaise (80%). In IV drug users, fever is present 98% of the time. Other symptoms include weakness, myalgias, dyspnea, chest pain, cough, headache, and anorexia. Neurologic signs and symptoms (eg, confusion, personality changes, decreased level of consciousness, and focal motor deficits) are seen in 30% to 40% of patients. Vasculitic lesions, including petechiae, splinter hemorrhages, tender fingertip nodules (Osler nodes), and nontender palmar plaques (Janeway lesions) are seen in 35% of patients. Splenomegaly, new heart murmur, and retinal hemorrhages may also be detected on physical examination. Risk factors for infective endocarditis include rheumatic or congenital heart disease, calcific degenerative valve disease, prosthetic heart valve, mitral valve prolapse, a history of IV drug use, or a history of endocarditis. Although any valve can be affected, IV drug use is the most common cause of right-sided endocarditis. The recurrence rate in these patients is 41%, significantly higher than the rate of less than 20% in non-IV drug use patients. (a) Also known as sinus node dysfunction or tachy-brady syndrome, sick sinus syndrome results from any combination of intermittent fast and slow heart rhythms associated with AV block and inadequate escape rhythm. The diagnosis is usually made with outpatient Holter monitoring. (b) Myocarditis results from inflammatory damage to the myocardium. The etiology may be infectious. Bacteria and enteroviruses, especially Coxsackie B virus and adenovirus, predominate as causative agents. Worldwide, Chagas disease is the leading cause, especially in South America. Often myocarditis presents with flu-like complaints, including fever, fatigue, and myalgias. Tachycardia out of proportion to the temperature or clinical picture may be present. Vasculitis lesions, Janeway lesions, and retinal hemorrhages are not expected. (c) Pericarditis is caused by inflammation of the pericardial sac. The etiology is broad, including infection, trauma, metabolic diseases (eg, uremia), medications, systemic autoimmune diseases, and most often the cause is idiopathic.

(d) Cardiac tamponade is a large pericardial effusion that restricts ventricular filling and eventually stroke volume. The classic findings are hypotension, JVD, and muffled heart sounds (Beck triad).

5.       You are evaluating a 26-year-old woman with fatigue. She also complains of lightheadedness, some minor weight loss, and paresthesias in her hands and feet. On examination, her vital signs are normal, but you note pallor and glossitis. Laboratory evaluation reveals a hemoglobin of 9.8 g/dL (L) and a MCV of 102 fL (H).

Which of the following would be most likely to treat her condition?

A. Diet rich in green leafy vegetables

B. Diet rich in iron

C. Vitamin B12 supplementation

D. Folic acid supplementation

E. Iron supplementation

The answer is C.

EXPLANATION: Some clinical features are common to all megaloblastic anemias, anemia, pallor, weight loss, fatigue, and glossitis to name a few. Neurological symptoms are specific to vitamin B12 deficiency. Usually, treatment is parenteral vitamin B12 replacement weekly for 1 month, often with concurrent administration of folic acid. Once levels are established, oral therapy may be sufficient.

6.       A 58-year-old male complains of the sudden onset of syncope. It occurs without warning and with no sweating, dizziness, or light headedness. He believes episodes tend to occur when he turns his head too quickly or sometimes when he is shaving. Physical examination is unremarkable. He has no carotid bruits, and cardiac examination is normal. Which of the following is the best way to make a definitive diagnosis in this patient?

A. ECG

B. Carotid massage with ECG monitoring

C. Holter monitor

D. Electrophysiologic study to evaluate the AV node

E. Carotid duplex ultrasonogram

Correct. The answer is B.

EXPLANATION: When syncope occurs in an older patient as a result of head turning, wearing a tight shirt collar, or shaving over the neck area, carotid sinus hypersensitivity should be considered. It usually occurs in men above the age of 50. Baroreceptors of the carotid sinus are activated and pass impulses through the glossopharyngeal nerve to the medulla oblongata. Some consider the process to be quite rare. Gentle massage of one carotid sinus at a time may show a period of asystole or hypotension. This should be performed in a controlled setting with monitoring and atropine available. Most cases of carotid sinus hypersensitivity are not associated with significant carotid stenosis; if a carotid bruit is heard on physical examination, however, a duplex study should precede carotid massage. More expensive studies, such as Holter monitoring or electrophysiologic study, would be unnecessary if carotid sinus massage demonstrates the diagnosis.

7.       A 45-year-old woman who had two normal pregnancies 15 and 18 years ago presents with the complaint of amenorrhea for 7 months. She expresses the desire to become pregnant again. After exclusion of pregnancy, which of the following tests is next indicated in the evaluation of this patient's amenorrhea?

A. Hysterosalpingogram

B. Endometrial biopsy

C. Thyroid function tests

D. Testosterone and DHAS levels

E. LH and FSH levels

Correct. The answer is E.

EXPLANATION: This patient has secondary amenorrhea, which rules out abnormalities associated with primary amenorrhea such as chromosomal abnormalities and congenital Müllerian abnormalities. The most common reason for amenorrhea in a woman of reproductive age is pregnancy, which should be evaluated first. Other possibilities include chronic endometritis or scarring of the endometrium (Asherman syndrome), hypothyroidism, and ovarian failure. The latter is the most likely diagnosis in a woman at this age. In addition, emotional stress, extreme weight loss, and adrenal cortisol insufficiency can bring about secondary amenorrhea. A hysterosalpingogram is part of an infertility workup that may demonstrate Asherman syndrome, but it is not indicated until premature ovarian failure has been excluded. Persistently elevated gonadotropin levels (especially when accompanied by low serum estradiol levels) are diagnostic of ovarian failure.

8.       A 72-year-old man has an altered sensorium after a high-speed motor vehicle collision and is placed in the intensive care unit for monitoring overnight. Which of the following strategies should be used in order to avoid the development of an aspiration pneumonia?

A. Nasogastric decompression

B. Steroids

C. Prophylactic antibiotics

D. Antacid administration

E. High positive end-expiratory pressure

Correct. The answer is A.

EXPLANATION: Immediate emptying of the stomach after traumatic injury and nasogastric decompression are important for the prevention of aspiration of gastric contents. Elevation of the head of the bed is also recommended for ICU patients. Prophylactic antibiotics are not indicated in high-risk patients, even after gross aspiration. Although gross aspiration results in a chemical pneumonitis, antibiotics are indicated only if pneumonia develops. Antacids result in loss of the protective effect of acidification of gastric contents and subsequent colonization with gramnegative organisms, and therefore should be avoided. Sucralfate may be a better choice for stress ulcer prophylaxis. Steroids are not indicated. High positive end expiratory pressure is not required in patients unless respiratory failure develops.

9.       A 48-year-old man presents with jaundice and right upper quadrant pain. Endoscopy shows blood coming from the ampulla of Vater. True statements regarding hemobilia include which of the following?

A. The classic presentation includes biliary colic, jaundice, and GI bleeding.

B. Spontaneous bleeding secondary to hematologic disorders is the major cause of this disorder.

C. Percutaneous transhepatic catheter placement of an absorbable gelatin sponge (Gelfoam) is the preferred treatment in cases of significant intrahepatic bleeding.

D. Angiography and endoscopy have no role in the treatment of intrahepatic bleeding.

E. Arterial embolization is advocated for hemobilia from the extrahepatic bile ducts.

Correct. The answer is A.

EXPLANATION: The classic Quincke triad of abdominal pain in the right upper quadrant, jaundice, and GI bleeding is present in 30% to 40% of patients with hemobilia. With more frequent use of percutaneous liver procedures (eg, transhepatic cholangiogram, transhepatic catheter drainage), iatrogenic injury has replaced other trauma as the most common cause of bloody bile. Other causes include spontaneous bleeding during anticoagulation, gallstones, parasitic infections/abscesses, and neoplastic lesions. Angiography and endoscopy are useful diagnostic studies, and intrahepatic bleeding can be controlled by angiographic embolization in up to 95% of cases. Surgical treatment is advocated for bleeding from extrahepatic bile ducts or the gallbladder or in cases of penetrating trauma in which associated injuries might need attention.

10.   A 29-year-old woman develops frequent, debilitating migraine headaches. Sumatriptan is prescribed for abortive therapy. Not long after taking the drug she is rushed to the hospital. Her vital signs are unstable, and she has muscle rigidity, myoclonus, generalized CNS irritability and altered consciousness, and shivering. You learn that for several months she had been taking another drug with which the triptan interacted. Which of the following was the most likely drug?

A. Acetaminophen

B. Codeine

C. Diazepam

D. Fluoxetine

E. Phenytoin

The answer is D.

EXPLANATION: This patient has what is almost certainly the serotonin syndrome. The triptan "adds" serotonin to the circulation, and its neuronal reuptake will be blocked by fluoxetine (or sertraline, others), which is classified as a selective serotonin reuptake inhibitor (SSRI) antidepressant. When sumatriptan (or other triptans used for migraine) is added, rapid accumulation of serotonin and/or the triptan in the brain can occur. The other drugs listed are not likely to interact with this serotoninergic drug.

11.   A patient is found to have elevated levels of direct-acting plasma bilirubin. Which of the following is the most likely diagnosis?

A. Tropical sprue

B. Terminal ileal bypass

C. Pancreatitis

D. Obstruction of the common bile duct

E. Bile reflux gastropathy

The answer is D.

EXPLANATION: When plasma bilirubin is increased due to bile duct obstruction, it is generally the conjugated form of bilirubin that increases due to reabsorption of bilirubin glucuronide into the blood.

12.   A young boy was admitted to the emergency room after having experienced severe nausea, headache, and fever. The neurologist concluded that he was suffering from a form of bacterial meningitis. His cerebrospinal fluid (CSF) would most likely indicate which of the following?

A. Increased protein, decreased glucose, decreased neutrophils

B. Increased protein, decreased glucose, increased neurophils

C. Increased protein, normal glucose, normal neutrophils

D. Decreased CSF pressure, decreased protein, decreased glucose

E. Decreased protein, normal CSF pressure, increased glucose

The answer is B

EXPLANATION: In individuals suffering from bacterial meningitis, the CSF is under increased pressure. Glucose levels are low relative to serum levels because of one or more of the following: glucose utilization by the bacteria, reduced glucose transport at the choroid plexus, increased glucose transport out of the CSF by breakdown of the blood-brain barrier and edema; neutrophils are increased in response to the bacteria, and protein is also increased, possibly because of a subarachnoid block, loss of tight junctions, and leaky capillaries.

13.   A 57-year-old man from Colombia presents to the emergency department with fever, night sweats, and a productive cough. A sputum smear shows acid-fast bacilli, and the patient is started on several medications. Three months later, the patient returns to the emergency department with reduced visual acuity and an inability to see the color green. Which of the following is the most likely cause of this patient’s change in visual acuity?

(A) Ethambutol toxicity

(B) Isoniazid toxicity

(C) Pyrazinamide toxicity

(D) Rifampin toxicity

(E) Tuberculous eye infection

The correct answer is A. Ethambutol is active only against Mycobacterium tuberculosis, and it

is among the fi rst-line agents used to treat tuberculosis (TB) infection (others are isoniazid, rifampin, and pyrazinamide). Ethambutol’s mechanism of action appears to be the inhibition of polymerization of cell wall precursors. Although the drug is generally well tolerated, its most common adverse effects involve ocular toxicity such as the kind described in this question, which usually appears several months after the initiation of treatment. Ethambutol is usually used in an anti-TB regimen with rifampin for patients who either cannot tolerate isoniazid or are infected with isoniazid-resistant M. tuberculosis.

14. A 53-year-old woman experiences hot fl ashes associated with menopause. She calls her  primary care physician to ask for advice about the risks and benefi ts of hormone replacement therapy (HRT). Which of the following is a potential benefi t of HRT?

(A) Decreased risk of breast cancer

(B) Decreased risk of deep venous thrombosis

(C) Decreased risk of hip fracture

(D) Decreased risk of myocardial infarction

(E) Decreased risk of stroke

The correct answer is C. Menopause occurs when a woman has no menstrual cycles for 1 year. The 2–8 years leading up to this time are called perimenopause. During this time,  hormones fl uctuate tremendously, eventually leading to a decrease in estrogen, an increase in

follicle-stimulating hormone (FSH), an increase in luteinizing hormone (LH), and an increase in gonadotropin-releasing hormone (GnRH). Associated symptoms include hot fl ashes, vaginal atrophy, osteoporosis, and coronary artery disease. (Remember, menopause causes HAVOC: Hot fl ashes, Atrophy of the Vagina, Osteoporosis, and Coronary artery disease.) Combinations of estrogen and progestin are used as HRT to decrease hot fl ashes, vaginal dryness, mood swings, and postmenopausal osteoporosis. Unfortunately, HRT has recently been associated with an increased risk of breast cancer, stroke, myocardial infarction in the first year after starting therapy, and deep venous thrombosis leading to pulmonary embolism. However, HRT has also been associated with potential benefi ts including decreased risks of hip fracture and colorectal cancer.

Answer A is incorrect. The risk of breast cancer is increased by 26% in women receiving HRT. Breast cancer has been shown to be an estrogen-dependent disease. Women who have never been exposed to estrogen, through a lack of ovarian function and absence of hormone treatment, do not develop breast cancer.

Answer B is incorrect. The risk of deep venous thrombosis and pulmonary embolism is  doubled in women receiving HRT. While no conclusive evidence has been found to date, it is surmised that the progestin component of HRT may counteract the benefi cial effects of  strogen

on the cardiovascular system.

Answer D is incorrect. The risk of myocardial infarction is increased by 29% in women  receiving HRT. While no conclusive evidence has been found to date, it is surmised that the progestin component of HRT may counteract the benefi cial effects of estrogen on the cardiovascular system.

Answer E is incorrect. The risk of stroke is increased by 41% in women receiving hormone replacement therapy. While no conclusive evidence has been found to date, it is surmised that the progestin component of HRT may counteract the benefi cial effects of estrogen on  the cardiovascular system.

15. Low-molecular-weight heparins (LMWH) are distinct from unfractionated heparin in several ways. Which of the following is the primary target of LMWH?

(A) Antithrombin III

(B) Factor IIa

(C) Factor VII

(D) Factor Xa

(E) Factors II, IX, and X

The correct answer is D. LMWHs act predominantly on Xa, whereas unfractionated heparin targets both Xa and IIa. A major advantage of using LMWHs over unfractionated heparin is that there is no need for monitoring of APTT.

Answer A is incorrect. Heparin targets both antithrombin III and Xa.

Answer B is incorrect. Factor IIa, or thrombin, is the enzyme that catalyzes the fi nal step of the clotting cascade, the formation of fi brin. Thrombin is a vitamin K-dependent factor that is not influenced by low-molecular-weight heparin.

Answer C is incorrect. Factor VII is part of the extrinsic pathway and is one of the vitamin K-dependent factors.

Answer E is incorrect. Warfarin blocks the activation of vitamin K-dependent factors II, VII,

IX, and X

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