Board Review Questions in Internal Medicine

Aharon Sareli, MD, Chief Medical Resident; Richard Sacks, MD, Chief Medical Resident; Girish Anand, MD, Chief Medical Resident, Mariana de Jongh, MD, Chief Medical Resident; Steven L. Sivak, MD, The Paul J. Johnson Chairman of Medicine, Department of Medi

1. A 26-year-old white woman presents to your office complaining of a foul-smelling vaginal discharge, which started 1 week ago. She has had multiple sexual partners and does not use condoms. Physical examination shows no signs of ulcers, lesions, or rash on her vulva. Speculum examination reveals a gray, adherent, foul-smelling discharge on the walls of the vaginal vault. Microscopy demonstrates multiple white blood cells (WBCs) as well as clue cells. What is the most effective treatment for this infection?

A. Metronidazole (Flagyl)

C. Doxycycline (eg, Adoxa, Doryx, Vibramycin)

E. Ketoconazole (Nizoral)

2. A 29-year-old college student comes to your office complaining of progressive shortness of breath, which has been accompanied by a dry, nonproductive cough of 3 weeks' duration as well as a low-grade fever. She tested positive for HIV infection 7 years ago but has not seen a physician since and is not taking any medications. Physical examination shows she is moderately distressed, with a respiratory rate of 28 breaths/min. Her vital signs are: blood pressure (BP), 126/76 mm Hg; heart rate, 98 beats/min; temperature, 100.4?F. Chest examination reveals crackles in the lower lung fields bilaterally. A chest x-ray is remarkable for diffuse bilateral interstitial infiltrates emanating from the hila in a "butterfly pattern." An arterial blood gas measurement on room air shows: pH, 7.47; PaCO2, 34 mm Hg; PaO2, 77 mm Hg. What is the most appropriate treatment?

A. Ceftriaxone (Rocephin) and azithromycin (Zithromax)

C. TMP-SMX (Bactrim, Cotrim, Septra)

E. Atovaquone (Mepron) and clindamycin (Cleocin)

3. A 31-year-old white woman comes to your outpatient clinic complaining of sudden-onset, severe retrosternal pain that woke her up the previous night. She has no significant medical history other than moderate facial acne, for which she takes tetracycline HCl (Sumycin), 250 mg, at bedtime. Minutes after eating breakfast that morning, the pain reoccurred. It had no radiation and was associated only with mild nausea. The pain was reduced by lunchtime, but she avoided lunch. She appears to be a healthy woman, and her vital signs are within normal limits. Results of the physical examination are unremarkable. Besides discontinuing the tetracycline, what would be the best next step in management?

A. Immediate endoscopy and prescribing a proton pump inhibitor

C. Prescribing metoclopramide (Reglan)

E. Prescribing tegaserod (Zelnorm)

4. A 28-year-old white man presents with concerns about his risk of developing colon cancer. He has no significant medical history and does not smoke or drink alcohol. His 52-year-old father was diagnosed with 2 adenomatous polyps during a screening colonoscopy. Physical examination is unremarkable, and he has hemoccult-negative brown stools. He is very anxious about his risk of colon cancer and asks when he should get a colonoscopy. What should you tell him?

A. At age 50 years, then every 10 years

C. At age 42 years, then every 10 years

E. At age 42 years, then every 5 years

5. A 39-year-old woman presents to the emergency department 9 days after delivering a full-term healthy baby by caesarean section. She complains of shortness of breath that started the previous day, has progressively worsened, and is accompanied by a cough that is minimally productive of white-pink sputum. She denies chest pain, palpitations, fever, or chills. Physical examination shows she is severely distressed and tachypneic. Vital signs are: heart rate, 120 beats/min; BP, 230/120 mm Hg; temperature, 37?C; respiratory rate, 34 breaths/min. She has bilateral diffuse crackles in both lung fields. Cardiac sounds are normal, and no murmurs are heard. She has 2+ pedal edema bilaterally. Chest x-ray reveals bilateral diffuse alveolar infiltrates. An arterial blood gas measurement on 50% Venturi mask shows: pH, 7.17; PaCO2, 77 mm Hg; PaO2, 54 mm Hg. Urinalysis reveals no red blood cells (RBCs) per high-power field (HPF) on microscopy, 3 WBCs per HPF on microscopy, and 3+ protein on dipstick testing. What is the most likely diagnosis?

A. Fat embolism leading to adult respiratory distress syndrome (ARDS)

C. Preeclampsia leading to ARDS

E. Postpartum sepsis leading to ARDS

6. A 26-year-old woman with cystic fibrosis tells you she has been coughing up blood since yesterday. She describes 3 separate episodes that started with coughing up yellow, foul-smelling sputum, followed by at least 5 cc of frank blood. She has had no previous episodes of hemoptysis. She uses tobramycin (AKTob, Defy, Tobrex) nebulizations. Outpatient pulmonary function test results from a week ago, when she was feeling well, revealed a forced expiratory volume in 1 second (FEV1) of 0.67 L. A high-resolution computed tomography (CT) scan done at the same time showed significant bronchiectasis bilaterally. The patient is sent to the emergency department for further workup. In the emergency department, she has a coughing episode that produces 75 cc of hemoptysis, but she is hemodynamically stable. Chest x-ray appearance is unchanged compared with previous radiographs. All the following interventions can be considered, except:

A. Intravenous (IV) antibioticsB. Bronchial artery embolization

D. Bronchoscopy

7. A 47-year-old black man presents for a routine checkup. He has no complaints and feels well. He is a nonsmoker, his body mass index is 25 kg/m², and his medical history is significant only for type 2 diabetes that is very well controlled with metformin HCl (Glucophage), 500 mg po bid. His hemoglobin A1C is 6.3 mg/dL. During his first "well visit" (his initial visit to your practice), his BP was 132/84 mm Hg. When he returned 4 weeks later to have some work done for a driver's license renewal, his BP was 126/88 mm Hg. Today, 4 weeks later, it is 124/86 mm Hg. What would be the most appropriate approach at this point?

A. Advise him to continue following the American Diabetes Association diet, lose weight, and restrict sodium intake to <2.4 g/day

C. Start antihypertensive therapy

E. Options A and B

8. A 29-year-old emergency medicine resident in Philadelphia asks your opinion about several lesions on his right forearm and hand (Figure 1). He first noticed them when he woke up that morning. They are mildly uncomfortable but not pruritic. He had been hiking in New Jersey during the weekend and had slept outside in a tent. He does not recall a spider bite but says he cannot be certain. A few days before the hike, he developed a sore throat, cough, and rhinorrhea, and treated himself with penicillin; he completed the course last night. What would be the diagnosis and appropriate treatment?

A. Erythema multiforme; no specific treatment

C. Erythema chronicum migrans; doxycycline (eg, Adoxa, Doryx, Vibramycin)

E. Urticaria; topical antihistamine cream

9. A 54-year-old white man is brought to the emergency department by his wife. She says that he has had severe abdominal pain for 2 days and has been confused and lethargic for the past 8 hours. She says he drinks approximately 1 pint of cognac daily and takes 2 acetaminophen (Tylenol) tablets almost every 4 hours. He has not seen a physician "for years." His vital signs are: BP, 113/63 mm Hg; heart rate, 103 beats/min; temperature, 37.8?C. He is deeply jaundiced, has bilateral parotid enlargement, and has tender hepatomegaly of 17-cm span. Liver function tests reveal: total bilirubin, 8 mg/dL; direct bilirubin, 5.5 mg/dL; aspartate aminotransferase (AST), 450 U/L; alanine aminotransferase (ALT), 162 U/L; alkaline phosphatase, 150 U/L. Prothrombin (PT) time is 20 seconds (normal, 10 seconds), and partial thromboplastin time is 46 seconds (normal, 29 seconds). Acetaminophen concentration is 4 ?g/mL (therapeutic concentration, <10 ?g/mL). What would be the appropriate treatment?

N

A. -acetylcysteine (Mucomyst) and corticosteroids

C. Bile acid sequestrants

N

E. -acetylcysteine

10. A 45-year-old woman is brought to the emergency department by family members because of a change in mental status. Physical examination shows her temperature is 101?F, and she is drowsy and confused. Her BP is 126/84 mm Hg, and her heart rate is 82 beats/min. The rest of the examination is normal. Coagulation parameters are within normal limits; the platelet count is 85 x 103/?L. Creatinine concentration is elevated at 2.2 mg/dL. Ahead CT scan is normal. A blood smear done for evaluation of anemia (hemoglobin, 10 g/dL) shows the presence of 3 schistocytes per HPF. What is the most appropriate management?

A. Fresh frozen plasma and platelet infusion

C. Plasma exchange

E. Hemodialysis

11. A 45-year-old man sees you for a routine evaluation. He has a history of stage 1 hypertension and is taking hydrochlorothiazide (eg, Esidrix, Ezide, Oretic), 25 mg po, daily. He has lived in the United States for 3 years after immigrating from Vietnam. He is married and has a very low-risk sexual history, with no known sick contacts. He was vaccinated with bacille Calmette-Gu?rin (BCG) as a child. Physical examination is unremarkable, and he is currently asymptomatic. A tuberculin skin test (TST) shows 12 mm of induration. His chest radiograph is clear. What would be the most appropriate next step in management?

A. Treat with isoniazid (INH) for 9 months

C. Treat with INH for 6 months

E. Repeat the TST to look for a "booster reaction"

12. A 56-year-old man presents to your office with a 1-month history of progressive shortness of breath and mild cough. He has type 2 diabetes and hypertension, and had renal transplantation 2 years ago. His medications include tacrolimus (Protopic), mycophenolate (CellCept, Myfortic), 70/30 insulin, metoprolol (Lopressor), and aspirin. Allograft function has been stable. His chest radiograph shows a dense right-lower lobe infiltrate. The sputum Gram's stain shows delicate, weakly gram-positive, irregularly stained beading filamentous structures. Acid-fast staining is weakly positive. What would be the most appropriate treatment?

A. Lipid formulation amphotericin B (eg, Abelcet, AmBisome, Amphotec)

C. Oral amoxicillin (Amoxil, Trimox)

E. Imipenem cilastatin (Primaxin)

13. A 40-year-old man is brought to the emergency department after being found unresponsive on the sidewalk. He is unkempt, covered with vomitus, and cannot be aroused. Medical history is not available. BP is 110/60 mm Hg, pulse is 110 beats/min, and respirations are 14 breaths/min, with a fruity odor. Core temperature is 35?C. He has right-sided coarse inspiratory crackles on chest auscultation. Neurologic examination is normal. Chest radiography is consistent with patchy, right-sided interstitial infiltrates. Initial laboratory studies show: sodium level, 137 mmol/L; potassium, 4.5 mmol/L; chloride, 102 mmol/L; bicarbonate, 26 mmol/L; blood urea nitrogen, 12 mg/dL; serum creatinine, 2 mg/dL. A random blood glucose measurement is 80 mg/dL. Serum is positive for acetone. The measured serum osmolality is 350 mOsm/kg, and a calculated osmolality is 300 mOsm/kg. What is the most likely diagnosis?

A. Alcoholic ketoacidosis

C. Ethylene glycol ingestion

E. Diabetic ketoacidosis

14. A 65-year-old white man presents to your office complaining of lightheadedness and lethargy for a month. His history includes type 2 diabetes, hypertension, coronary artery disease, and stroke. He is taking insulin lispro (Humalog), glargine (Lantus), hydrochlorothiazide (eg, Esidrix, Hydro-Par, Oretic; 25 mg/d po), aspirin (325 mg/d po), and atorvastatin calcium (Lipitor; 20 mg/d po). His physical examination is remarkable for marked bradycardia, BP of 140/60 mm Hg, and mild chronic upper motor neuron left-seventh nerve palsy. Electrolytes are normal. You perform a 12-lead electrocardiogram ([ECG] Figure 2). What would be the most likely diagnosis and appropriate management?

A. Third-degree atrioventricular (AV) block; permanent pacemaker

C. Second-degree AV block, Mobitz type 2; atropine and observation

E. Second-degree AV block, advanced; permanent pacemaker

15. A 28-year-old woman develops an episode of dysuria and increased urinary frequency. She has had 2 urinary tract infections (UTI) in the past - 9 months ago and 3 months ago. Both episodes were treated with a 3-day course of TMP-SMX (Bactrim, Cotrim, Septra) with complete symptom resolution. Medical history is otherwise negative. She uses a diaphragm for birth control. The only drug she uses is acetaminophen (Tylenol) for occasional headaches. Physical examination shows she is afebrile with stable vital signs. There is no costovertebral angle tenderness. Urine dipstick examination is positive for nitrites and leukocyte esterase. What is the most appropriate next step in management?

A. Obtain urine cultures; if positive, start antibiotics

C. Prescribe TMP/SMX, 80 mg/400 mg, 3 times weekly for 6 to 12 months

E. Prescribe a 14-day course of an oral fluoroquinolone

16. A 50-year-old man presents with dysphagia to solids and liquids for the past 10 years. He also describes regurgitation and chest pain, and, with increasing frequency, feels food getting "stuck" distally. Frequently he has to perform maneuvers while eating, such as putting his arms over his head or straightening his back to be able to complete his swallow. The symptoms are progressive and currently occur with almost every meal. He denies weight loss. He brings a barium swallow radiography that shows a "bird-beak" appearance of the distal esophagus. What is the most likely diagnosis?

A. Zenker's diverticulum

C. Esophageal cancer

E. Esophageal web

17. A 59-year-old postmenopausal white woman who has never had a fracture had the following results on a recent dual energy x-ray absorptiometry test: spine T score, -2.6 and Z score, -1.2 ; hip T score, -1.4 and Z score, -0.9. What is the diagnosis using the World Health Organization (WHO) criteria for bone mass?

A. Osteopenia

C. Severe osteopenia

E. Normal bone mass

18. A 68-year-old white man presents with worsening lower back pain. He reports occasional throbbing left-sided headaches, which he says are relieved temporarily with over-the-counter analgesics. He denies any recent head trauma or history of malignancy and has been in relatively good health. Findings of the physical examination of the head, neck, and back are unremarkable. Calcium concentration is normal, but alkaline phosphatase is mildly elevated. As part of the workup, a skull x-ray is obtained, which reportedly shows "osteoporosis circumscripta." What is the most likely diagnosis and best initial treatment?

A. Multiple myeloma; vincristine sulfate (Vincasar PFS)-doxorubicin (Adriamycin)-dexamethasone (Decadron) chemotherapy

C. Osteogenic sarcoma; palliative chemotherapy

E. Paget's disease; bisphosphonates

ANSWERS

1 - A. The patient has bacterial vaginosis. A white-gray thin discharge is characteristic. Usually, there is no or only minimal erythema of the vaginal vault. A wet preparation of the discharge will show clue cells as well as abundant WBCs. Adding 10% potassium hydroxide to the discharge will produce a characteristic "positive whiff test" (ie, ammonia odor). Metronidazole, 500 mg bid for 7 to 10 days, is the recommended treatment. Alternative treatments are clindamycin (Cleocin), 300 mg bid for 7 days, or clindamycin cream 2%, 5 g intravaginally at bedtime for 7 days. Routine treatment of the partner is not recommended.

References

Am J Obstet Gynecol

Beigi RH, Austin MN, Meyn LA, et al. Antimicrobial resistance associated with the treatment of bacterial vaginosis. . 2004;191:1124-1129.

Centers for Disease Control and Prevention. Sexually Transmitted Diseases Treatment Guidelines 2002. Available at www.cdc.gov/std/treatment. Accessed April 7, 2005.

2 - C. The patient most likely has Pneumocystis carinii pneumonia, which has recently been reclassified as Pneumocystis jiroveci. In mild cases, the clinical examination may be normal. The characteristic chest x-ray shows bilateral diffuse interstitial infiltrates radiating from the hila in a butterfly distribution. CT scan of the chest will show areas of "ground glass." First-line treatment is TMP-SMX, with corticosteroids added if, on room air, arterial oxygen is less than 70 mm Hg or if the alveolar/arterial oxygen tension difference is more than 35 mm Hg. References The National Institutes of Health-University of California Expert Panel for Corticosteroids as Adjunctive Therapy for Pneumocystis Pneumonia. Consensus statement on the use of corticosteroids as adjunctive therapy for Pneumocystis pneumonia in the acquired immunodeficiency syndrome. N Engl J Med. 1990;323:1500-1504. Mofenson LM, Oleske J, Serchuck L, et al. Treating opportunistic infections among HIV-exposed and infected children. MMWR Recomm Rep. 2004 Dec 3;53 (RR-14):1-92.

3 - D. This patient most likely has drug-induced esophagitis secondary to tetracycline HCl use. The most common symptoms are odynophagia, dysphagia, and retrosternal chest pain. Most episodes resolve within 7 to 10 days. Frequently, tetracycline tablets that are swallowed with little or no water before bedtime cause the ulceration. Sucralfate or mucosal coating agents, along with discontinuation of the tetracycline, would be appropriate. The role of proton pump inhibitors is poorly defined. An endoscopy would be considered if symptoms persisted for more than 7 to 10 days.

References

Gastrointest Endosc.

Banisaeed N, Truding RM, Chang CH. Tetracycline-induced spongiotic esophagitis: a new endoscopic and histopathologic finding. 2003;58:292-294.

The Esophagus.

Kikendall JW, Johnson LF. Pill-induced esophageal injury. In: Castell DO, ed. 2nd ed. Boston, Mass: Little, Brown; 1995:619-633.

4 - D. This patient is at higher-than-average risk for colorectal carcinoma. Adenomatous polyps in a first-degree relative increase the risk as much as colorectal cancer. Individuals who are not at increased risk should have an initial screening colonoscopy at age 50 years and then every 10 years. Those with a firstdegree relative with colorectal cancer or adenomatous polyps should start at age 40 years, or 10 years younger than the age the relative was first diagnosed, whichever is earlier. Screening should also be done every 5 years, not every 10 years. Reference Winawer S, Fletcher R, Rex D, et al, for the US Multisociety Task Force on Colorectal Cancer. Colorectal cancer screening and surveillance: clinical guidelines and rationale - update based on new evidence. Gastroenterology. 2003;124:544-560.

5 - D. It is important to consider preeclampsia even after delivery, since it may occur from 20 weeks of gestation until 4 weeks postpartum. It is characterized by hypertension (BP = 140 mm Hg systolic or =90 mm Hg diastolic in a person previously undiagnosed with hypertension after the 20th week of gestation). In addition, 0.3 g of proteinuria should be present in a 24-hour sample (usually corresponding with 1+ protein on urine dipstick testing). Patients may present postpartum with severe hypertension and sudden-onset shortness of breath (caused by pulmonary edema), abdominal pain, visual disturbance, headache, or seizures. Magnesium sulfate is used to prevent seizures in patients with severe preeclampsia and to treat seizures in eclamptic patients.

References

Obstet Gynecol Clin North Am

Gregg AR. Hypertension in pregnancy. . 2004;31:223-241.

Am Fam Physician

Wagner LK. Diagnosis and management of preeclampsia. . 2004;70:2317-2324.

Am J Obstet Gynecol

Chames MC, Livingston JC, Ivester TS, et al. Late postpartum eclampsia: a preventable disease? . 2002;186:1174-1177.

6 - C. This patient's hemoptysis is likely from the areas of bronchiectasis. She needs to be evaluated with bronchoscopy to localize the source of bleeding. IV antibiotics with antipseudomonal cover should be initiated. Bronchial artery embolization is an option to stop massive or recurrent hemoptysis. Unfortunately, this patient's extremely low FEV₁ would preclude lung surgery. References Jean-Baptiste E. Clinical assessment and management of massive hemoptysis. Crit Care Med. 2000;28:1642-1647. Antonelli M, Midulla F, Tancredi G, et al. Bronchial artery embolization for the management of nonmassive hemoptysis in cystic fibrosis. Chest. 2002;121:796-801. Beckles MA, Spiro SG, Colice GL, et al. The physiologic evaluation of patients with lung cancer being considered for resectional surgery. Chest. 2003;123(suppl):105S-114S.

7 - D. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC7) introduced the category of "prehypertension," defined as a BP of 120 to 139 mm Hg systolic and 80 to 89 mm Hg diastolic. Ischemic heart disease, diabetes mellitus, heart failure, chronic kidney disease, and cerebrovascular disease (dubbed "compelling indications") are now regarded as high-risk conditions that mandate the use of antihypertensive therapy. The JNC7 emphasizes the importance of lifestyle modification, including the Dietary Approaches to Stop Hypertension (DASH) diet, weight loss, regular exercise, low salt intake, and alcohol moderation for all patients with prehypertension or with stage 1 or stage 2 hypertension. In patients with prehypertension but no compelling indications, lifestyle modification is the initial intervention. Those with compelling indications should also be prescribed appropriate antihypertensive therapy.

Reference

JAMA.

Chobanian AV, Bakris GL, Black HR, et al. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure: the JNC7 report. 2003;289:2560-2572.

8 - A. The lesion shown is erythema multiforme. The etiology is idiopathic in 50% of cases. It may occur postinfection (eg, after herpes simplex virus or mycoplasma infections) and may be associated with drugs, such as sulfonamides, phenytoin (Dilantin), barbiturates, penicillin, or allopurinol (Zyloprim). In this patient, the lesion may be a reaction to penicillin or secondary to a viral infection. Erythema multiforme with minor lesions, such as those described in this case, causes minimal discomfort and regresses spontaneously in 2 to 4 weeks. The more severe form with a generalized rash is called "erythema multiforme major." Stevens-Johnson syndrome is the life-threatening form.ReferencesAyangco L, Robers RS III. Oral manifestations of erythema multiforme. Dermatol Clin. 2003;21:195-205.Fitzpatrick TB, Johnson RA, Wolff K, et al. Color Atlas and Synopsis of Clinical Dermatology: Common and Serious Diseases. 4th ed. New York, NY: McGraw-Hill; 2000:332-334.

N

9 - A. The patient has features consistent with alcoholic hepatitis. His bilirubin levels are elevated, and the aspartate AST/ALT ratio is very suggestive at approximately 3:1. Corticosteroids would be indicated for severe alcoholic hepatitis, defined by a Maddrey's discriminant function (4.6 x [PT time prolongation in seconds] + serum bilirubin [mg/dL]) score of more than 32 or the presence of hepatic encephalopathy. This patient qualifies using either criterion. -acetylcysteine should be used when acetaminophen toxicity is suspected, even though his acetaminophen levels are now within the therapeutic range.

Reference

Clin Liver Dis.

O'Shea RS, McCullough AJ. Treatment of alcoholic hepatitis. 2005;103-134.

10 - C. This patient has thrombotic thrombocytopenic purpura (TTP), a syndrome characterized by microangiopathic hemolytic anemia, thrombocytopenia, neurologic abnormalities, fever, and renal dysfunction (the "pentad"). Early intervention has a significant impact on outcome. The introduction of plasma exchange has increased survival up to 82%. Plasma exchange therapy should be continued for several days beyond normalization of the platelet counts. It is crucial to avoid platelet transfusions despite the presence of severe thrombocytopenia. Normal coagulation factors rules out the possibility of disseminated intravascular coagulopathy. There is no established role for activated protein C or broadspectrum antibiotics in TTP. Reference Nabhan C, Kwaan HC. Current concepts in the diagnosis and management of thrombotic thrombocytopenic purpura. Hematol Oncol Clin North Am. 2003;17:177-199.

11 - A. This patient is at high risk for latent TB infection because he is foreign-born and comes from a country with a high prevalence of the disease. Thus TST is indicated. History of BCG vaccination is often cited as a reason for TST positivity. However, history of vaccination can be ignored when interpreting a TST, because tuberculin reactivity caused by BCG vaccination generally wanes with time, and most people who have received BCG come from countries with a high incidence of TB. In an asymptomatic patient with a normal chest radiograph, there is no need to obtain induced sputa. In this man, a TST reaction of more than 10 mm is considered positive. He has latent TB infection, since the TST is 12 mm. The usual recommended treatment is INH for 9 months. Prospective randomized trials of up to 12 months of therapy in HIV-uninfected patients suggest that the maximal benefit of INH is with 9 months therapy, although a 6-month regimen still confers protection and can be used under some circumstances. Alternatives, such as rifampin (Rifadin) for 4 months or INH combined with pyrazinamide for 2 months, have been used in patients unable to tolerate INH or comply with a 9-month regimen.

References

N Engl J Med

Am J Respir Crit Care Med.

Jasmer RM, Nahid P, Hopewell PC. Latent tuberculosis infection. . 2002;347:1860-1866. American Thoracic Society. Targeted tuberculin testing and treatment of latent tuberculosis infection. 2000; 161:S221-S247.

12 - D. This case illustrates nocardial infection in a patient who is clearly at risk for opportunistic infections (allograft recipient with immunosuppressive therapy). Nocardia are aerobic actinomycetes that usually infect via the respiratory tract. The presence of delicate, weakly gram-positive, irregularly stained beading filaments is vital in the identification of this organism. Many nocardia species are acid fast but retain fuchsin less tenaciously than mycobacteria. This point is key to answering this question correctly. Cultures may grow in a few days but usually require 2 to 3 weeks of incubation. Other at-risk patients include those with malignancies (particularly lymphoreticular) or chronic pulmonary disorders (eg, alveolar proteinosis). Treatment of choice is TMP-SMX (with or without amikacin sulfate [Amikin] in the initial stage). Amphotericin B, voriconazole, or caspofungin acetate are all treatments for invasive pulmonary aspergillosis. Amoxicillin is used to treat actinomycosis. Imipenem cilastatin has no role in the treatment of any of these infections.

Reference

Mandell, Douglas and Bennett's Principles and Practice of Infectious Diseases

Mandell GL, Bennett JE, Dolin R, eds. . 4th ed. New York, NY: Churchill Livingstone Inc; 1995:2273-2280.

13?D. The key points in this case are unresponsiveness and elevated serum acetone level in the face of normal acid-base status. Acetone is usually converted to acetic acid, which results in an elevated serum anion gap. However, if the carbon-carbon bond in acetone is stable, acetic acid will not be generated, thus no primary metabolic acidosis will occur. (This can occur in isopropanol ingestion with its metabolism to acetone by hepatic alcohol dehydrogenase. Bear in mind that isopropanol may have cardiovascular effects, including hypotension, which may result in a secondary lactic acidosis.) The presence of an osmolar gap may suggest a toxic alcohol ingestion. Although ethylene glycol and methanol cause osmolar gaps, they are both typically associated with an anion gap metabolic acidosis. Both alcoholic and diabetic ketoacidoses present with anion gaps. Isopropanol is most often ingested but may be inhaled or transcutaneously absorbed. It is found in disinfectant solutions, industrial solvents, certain paints, inks, paint thinners, and hair tonics. Many patients with isopropanol toxicity have coingested ethanol. Most cases will resolve with supportive care. Gastrointestinal decontamination is unlikely to be effective in the absence of an in-hospital witnessed ingestion. However, if a coingestion is suspected, decontamination should be given.

Reference

Clinical Toxicology

Ford MD, Delaney KA, Ling LJ, et al, eds. Ford: . Philadelphia, Pa: WB Saunders Company; 2001:769-771.

14?E. Because it does not fit into a Mobitz type 1 (progressive lengthening of the PR interval followed by a nonconducted beat) or Mobitz type 2 (fixed PR interval before and after nonconducted beats) pattern, this ECG demonstrates what is termed advanced second-degree AV block (block of 2 or more consecutive P waves followed by a QRS complex). Third-degree AV block is defined as the absence of AV conduction. The marked bradycardia (heart rate, approximately 20 beats/min) would be an indication for pacing even in the absence of symptoms (class 1 indication). In patients with AV block, it is important to look for reversible factors (eg, drugs, electrolyte abnormalities) before committing the patient to a permanent pacemaker. In this case, however, there is no mention of any reversible factor. Although atropine may transiently help, a permanent pacemaker is the treatment of choice.

Reference

Circulation

Gregoratos G, Abrams J, Epstein AE, et al, for the American College of Cardiology/American Heart Association Task Force on Practice Guidelines/North American Society for Pacing and Electrophysiology Committee to Update the 1998 Pacemaker Guidelines. ACC/AHA/NASPE 2002 guideline update for implantation of cardiac pacemakers and antiarrhythmia devices. . 2002;106: 2145-2161.

Escherichia coli

15?C. The patient has recurrent UTI. It is estimated that half of all women will have at least 1 episode of acute cystitis, and 1 in 4 will have recurrent episodes. First-line treatment of acute uncomplicated UTI has traditionally been a 3-day regimen of TMP-SMX or TMP alone for patients with sulfa allergies. Increasing resistance of community-acquired to TMP-SMX worldwide has led to a reassessment of the most appropriate empiric therapy. Alternative first-line agents include the fluoroquinolones, nitrofurantoin (Macrodantin), and fosfomycin (Monurol). As many as 10% to 20% of women experience frequent recurrent UTI, as often as every few weeks. Options for the management of recurrent UTI include long-term (6-12 months) low-dose antimicrobial prophylaxis, postcoital prophylaxis, or self-treatment. Prophylactic antimicrobial therapy is generally considered for women with 2 symptomatic episodes within 6 months, or 3 episodes within 1 year. Antimicrobial options for long-term, low-dose prophylaxis include TMP-SMX, TMP, nitrofurantoin, or norfloxacin (Noroxin). Usually, therapy is continued for 6 to 12 months, but more extended durations of 2 to 5 years may be considered in patients with very frequent recurrences.

References

Dis Mon.

Nicolle LE. Urinary tract infection: traditional pharmacologic therapies. 2003;49:111-128.

Clin Infect Dis

Warren JW, Abrutyn E, Hebel JR, et al. Guidelines for antimicrobial treatment of uncomplicated acute bacterial cystitis and acute pyelonephritis in women. . 1999;29:745-758.

16?D. Achalasia has an estimated incidence of 1:100,000, affecting both genders equally, with an onset usually in the third to fifth decades. The most common presenting symptoms include dysphagia (82%-100%), regurgitation (56%-97%), weight loss (30%-91%), chest pain (17%-95%), and heartburn (27%-42%). Patients tend to drink a lot of fluids while eating or use maneuvers, such as straightening the back, raising their arms over their head, or standing to increase intraesophageal pressure and facilitate the emptying of food into the stomach. Esophageal manometry is used to confirm the diagnosis of achalasia and is particularly important when radiographs are normal or inconclusive. The characteristic radiographic finding is a dilated intrathoracic esophagus with an air-fluid level. The lower esophageal sphincter tapers to a point, giving the distal esophagus a beaklike appearance.

Patients with episodic and nonprogressive dysphagia to solids without significant weight loss often have an esophageal web or distal esophageal ring (Schatzki's ring). Dysphagia that occurs daily or is clearly worsening is more suggestive of a peptic stricture or esophageal malignancy. Significant weight loss, anorexia, or rapidly worsening dysphagia also favors malignancy. Dysphagia, halitosis, and regurgitation of food ingested up to several hours before symptoms are often characteristic in a patient with a large Zenker's diverticulum. Other symptoms may include discomfort in the throat, a palpable mass in the neck, and recurrent pulmonary aspiration.

References

Gastroenterol Clin North Am

Lind CD. Dysphagia: evaluation and treatment. . 2003;32:553-575.

Clin Fam Pract.

Saud BM, Szyjkowski RD. A diagnostic approach to dysphagia. 2004;6:525-546.

17?B. The WHO criterion for osteoporosis is a bone mineral density (BMD) 2.5 standard deviations (SD) or more below that of a "young normal" adult (ie, T score &#8804;?2.5. This definition applies to T scores from any skeletal site. Osteopenia describes a BMD between 1.0 and 2.5 SD below that of a young normal adult (ie, T score between ?1 and ?2.5). With a T score at the spine of ?2.6, this woman's condition meets the definition for osteoporosis. Since osteoporosis is present in the spine, this diagnosis takes precedence over the osteopenia in the hip. The WHO criteria do not include a classification of severe osteopenia. Established osteoporosis is defined as a BMD in the osteoporotic range with 1 or more fragility fractures. This patient did not have a bone fracture. Normal bone mass is a BMD within 1 SD of a young normal adult (ie, T score &#8804;?1).

References

World Health Organization. Assessment of Fracture Risk and Its Application to Screening for Postmenopausal Osteoporosis. A Report of a WHO Study Group. Geneva, Switzerland: WHO; 1994.

N Engl J Med.

Bone HG, Hosking D, Devogelaer JP, et al, for the Alendronate Phase III Osteoporosis Treatment Study Group. Ten years' experience with alendronate for osteoporosis in postmenopausal women. 2004;350:1189-1199.

18?E. This patient has Paget's disease of the bone, the cause of which is unknown. The primary defect appears to be an abnormality of the osteoclast. It usually affects individuals older than 50 years and is particularly common in eastern and northern European populations. The primary indication for treatment is the presence of symptoms. Not all symptoms respond, but bone pain usually does. The goal of treatment is to reverse negative bone balance using agents that inhibit bone resorption and stimulate growth, such as calcitonin (Miacalcin) or bisphosphonates. Most patients are asymptomatic at detection. Laboratory markers of disease activity are serum alkaline phosphatase and urinary hydroxyproline, which are usually elevated when bone destruction is occurring. Serum calcium and phosphorus concentrations are normal in most patients with Paget's disease. However, hypercalciuria and hypercalcemia can occur with immobilization or with fracture caused by unopposed increase in bone resorption. Osteoporosis circumscripta on skull x-ray is consistent with Paget's disease. Another characteristic radiologic finding is the "picture-frame" vertebral body, which is secondary to severe osteoporosis centrally and a thickened, sclerotic cortex.

References

N Engl J Med.

Delmas PD, Meunier PJ. The management of Paget's disease of bone. 1997;336:558-566.

Am J Med.

Reid IR, Nicholson GC, Weinstein RS, et al. Biochemical and radiologic improvement in Paget's disease of bone treated with alendronate: a randomized, placebo-controlled trial. 1996;101: 341-348.

Am Fam Physician.

Schneider D, Hoffman MT, Peterson JA. Diagnosis and treatment of Paget's disease of bone. 2002;65:2069-2072.