PRINCIPLES OF INTERNAL MEDICINE - PART 6 potx

This page intentionally left blank. 197 IX. DISORDERS OF THE KIDNEY AND URINARY TRACT QUESTIONS DIRECTIONS: Each question below contains five suggested responses. Choose the one best response to each question. IX-1. A patient with lymphoma who is known to excrete 1.5 g urinary protein per day has a negative dipstick eval- uation for urinary protein. The reason for the seeming inconsistency is (A) the size of the excreted protein is too small to be picked up by the test strip (B) the urine is not concentrated enough (C) only heavy chain sequences are recognized by the test strip (D) Tamm-Horsfall protein blocks the reaction be- tween the secreted protein and the test strip (E) dipsticks preferentially detect albumin compared with immunoglobulin because albumin is nega- tively charged IX-2. A 75-year-old female nursing home resident is brought to the emergency department because of increas- ing obtundation. She is found to communicate poorly. Brief physical examination reveals diminished skin tur- gor. Blood pressure is 100/60, pulse 120, respiratory rate 20, and temperature 37ЊC (98.6ЊF). Blood tests reveal the following serum electrolytes: sodium 160 mmol/L, po- tassium 5.0 mmol/L, bicarbonate 30 mmol/L, chloride 110 mmol/L. The most appropriate management at this time would include administration of 5% dextrose in (A) normal saline, 100 mL/h (B) normal saline solution, 250 mL/h (C) half normal saline, 100 mL/h (D) half normal saline, 200 mL/h (E) water, 150 mL/h IX-3. Laboratory evaluation of a 19-year-old man being worked up for polyuria and polydipsia yields the follow- ing results: Serum electrolytes (mmol/L): Na 144; K 4.0; ϩϩ Cl 107; HCO 25 ϪϪ 3 BUN: 6.4 mmol/L (18 mg/dL) Blood glucose: 5.7 mmol/L (102 mg/dL) Urine electrolytes (mmol/L): Na 28; K 32 ϩϩ Urine osmolality: 195 mosmol/kg water IX-3. (Continued) After 12 h of fluid deprivation, body weight has fallen by 5%. Laboratory testing now reveals the following: Serum electrolytes (mmol/L): Na 150; K 4.1; ϩϩ Cl 109; HCO 25 ϪϪ 3 BUN: 7.1 mmol/L (20 mg/dL) Blood glucose: 5.4 mmol/L (98 mg/dL) Urine electrolytes (mmol/L): Na 24; K 35 ϩϩ Urine osmolality: 200 mosmol/kg water One hour after the subcutaneous administration of 5 units of arginine vasopressin, urine values are as follows: Urine electrolytes (mmol/L): Na 30; K 30 ϩϩ Urine osmolality: 199 mosmol/kg water The likely diagnosis in this case is (A) nephrogenic diabetes insipidus (B) osmotic diuresis (C) salt-losing nephropathy (D) psychogenic polydipsia (E) none of the above IX-4. A 70-year-old man with diabetes mellitus and hy- pertension has the following serum chemistries: Electrolytes (mmol/L): Na 138; K 5.0; Cl 106; ϩϩϪ HCO 20 Ϫ 3 Glucose: 11 mmol/L (200 mg/dL) Creatinine: 176 ␮ mol/L (2.0 mg/dL) Which of the following may contribute to worsening hyperkalemia? (A) Propranolol (B) Verapamil (C) Theophyllin (D) Carbenicillin (E) Hydrochlorothiazide IX-5. A 40-year-old male alcoholic presents with a 6-day history of binge drinking. Serum chemistry tests reveal the following: Copyright 2001 The McGraw-Hill Companies. Click Here for Terms of Use. IX. D ISORDERS OF THE K IDNEY AND U RINARY T RACT — Q UESTIONS 198 IX-5. (Continued) IX-8. (Continued) Electrolytes (mmol/L): Na 145; K 5.0; Cl 105; ϩϩϪ HCO 15 Ϫ 3 BUN: 7.1 mmol/L (20 mg/dL) Creatinine: 133 ␮ g/L (1.5 mg/dL) Glucose: 9.6 mmol/L (172 mg/dL) The nitroprusside (Acetest) agent gives a minimally positive result. Optimal therapy to ameliorate the patient’s acid-base disorder would include 5% dextrose in (A) water (B) normal saline (C) normal saline, insulin, and sodium bicarbonate (D) half normal saline and insulin (E) half normal saline, insulin, and sodium bicarbonate IX-6. A 45-year-old woman who has had slowly progres- sive renal failure begins to complain of increasing numb- ness and prickling sensations in her legs. Examination re- veals loss of pinprick and vibration sensation below the knees, absent ankle jerks, and impaired pinprick sensation in the hands. Serum creatinine concentration, checked during her most recent clinic visit, is 790 ␮ mol/L (8.9 mg/ dL). The woman’s physician should now recommend (A) a therapeutic trial of phenytoin (B) a therapeutic trial of pyridoxine (vitamin B ) 6 (C) a therapeutic trial of cyanocobalamin (vitamin B ) 12 (D) initiation of renal replacement therapy (E) neurologic referral for nerve conduction studies IX-7. In patients with chronic renal failure, which of the following is the most important contributor to renal os- teodystrophy? (A) Impaired renal production of 1,25-dihydroxyvita- min D [1,25 (OH) D ] 323 (B) Hypocalcemia (C) Hypophosphatemia (D) Loss of vitamin D and calcium via dialysis (E) The use of calcitriol IX-8. A 50-year-old man is hospitalized for treatment of enterococcal endocarditis. He has been receiving ampi- cillin and gentamicin for the past 2 weeks but is persist- ently febrile. Laboratory results are as follows: Serum electrolytes (mmol/L): Na 145; K 5.0; ϩϩ Cl 110; HCO 20 ϪϪ 3 BUN: 14.2 mmol/L (40 mg/dL) Serum creatinine: 300 ␮ mol/L (3.5 mg/dL) Urine sodium: 20 mmol/L Urine creatinine: 3000 mmol/L (35 mg/dL) Which of the following is the most likely cause of this patient’s acute renal failure? (A) Tubular necrosis (B) Insensible skin losses (C) Renal artery embolism (D) Cardiac failure (E) Nausea and vomiting IX-9. A 23-year-old man has recurrent episodes of hema- turia over the past year. Each of the episodes seems to be associated with an upper respiratory infection. Physical examination currently is normal. Urinalysis reveals a rel- atively bland sediment; dipstick is positive for both pro- tein and blood. Renal biopsy most likely will reveal (A) extensive extracapillary proliferation on light microscopy (B) diffuse mesangial proliferation on light microscopy (C) autosomal dominant polycystic kidney disease (D) diffuse mesangial deposition of IgA on immuno- fluorescence (E) deposition of C3 in capillary walls on immunofluo- rescence IX-10. The condition of a 50-year-old obese woman with a 5-year history of mild hypertension controlled by a thia- zide diuretic is being evaluated because proteinuria was noted during her routine yearly medical visit. Physical examination disclosed a height of 167.6 cm (66 in.), weight 91 kg (202 lb), blood pressure 130/80 mmHg, and trace pedal edema. Laboratory values are as follows: Serum creatinine: 106 ␮ mol/L (1.2 mg/dL) BUN: 6.4 mmol/L (18 mg/dL) Creatinine clearance: 87 mL/min Urinalysis: pH 5.0; specific gravity 1.018; protein 3ϩ; no glucose; occasional coarse granular cast Urine protein excretion: 5.9 g/d IX. D ISORDERS OF THE K IDNEY AND U RINARY T RACT — Q UESTIONS 199 IX-10. (Continued) The results of a renal biopsy are shown below. Sixty percent of the glomeruli appeared as shown (by light microscopy); the remainder were unremarkable. The most likely diagnosis is (A) hypertensive nephrosclerosis (B) focal and segmental sclerosis (C) minimal-change (nil) disease (D) membranous glomerulopathy (E) crescentic glomerulonephritis IX-11. In a person who has carcinoma of the lung and the depicted urinalysis, renal biopsy most likely will show (A) minimal-change disease (B) diffuse proliferative glomerulonephritis (C) membranoproliferative glomerulonephritis (D) membranous glomerulopathy (E) focal glomerulosclerosis IX-12. Which of the following case histories would most likely be associated with the urinary sediment depicted? IX-12. (Continued) (A) A 23-year-old man with newly diagnosed lympho blastic lymphoma who is found to have a rising creatinine level 2 days after the administration of combination chemotherapy (B) A 23-year-old woman 1 year after surgery per formed because of morbid obesity (C) A 45-year-old woman with a history of multiple urinary tract infections with urea-splitting orga nisms IX. D ISORDERS OF THE K IDNEY AND U RINARY T RACT — Q UESTIONS 200 IX-12. (Continued) IX-15. (Continued) (D) A 40-year-old man with edema, hypoalbuminemia, and proteinuria (E) An 18-year-old man with flank pain, hematuria, and a positive family history for renal stones in youth IX-13. A 72-year-old woman with rheumatic heart disease is being treated with ampicillin and gentamicin for enter- ococcal endocarditis. One week into the course she de- velops a morbilliform skin rash and fever. Laboratory evaluation is remarkable for a doubling of serum creati- nine and blood urea nitrogen from their baseline values. Urinalysis dipstick is positive for blood, protein, and white cells. Ultrasonography reveals bilaterally enlarged kidneys. Based on the available data, the most likely cause of the patient’s azotemia is (A) tubular necrosis caused by aminoglycoside (B) membranous nephropathy resulting from endocar- ditis (C) enterococcal pyelonephritis (D) cystitis (E) hypersensitivity reaction to ampicillin IX-14. A 40-year-old woman who has never had signifi- cant respiratory disease is hospitalized for evaluation of hemoptysis. Urinalysis reveals 2ϩ proteinuria and micro- scopic hematuria. BUN concentration is 7.1 mmol/L (20 mg/dL), and serum creatinine concentration is 177 ␮ mol/L (2.0 mg/dL). Serologic findings include nor- mal complement levels and a negative assay for fluores- cent antinuclear antibodies. Renal biopsy reveals granu- lomatous necrotizing vasculitis with scattered immunoglobulin and complement deposits. The most likely diagnosis in this case is (A) mesangial lupus glomerulonephritis (B) Henoch-Scho¨nlein purpura (C) microscopic polyarteritis (D) Wegener’s granulomatosis (E) Goodpasture’s syndrome IX-15. Which of the following patients is most likely to develop destruction of renal papillae with concomitant tubulointerstitial damage? (A) A middle-aged man who has consumed “moon- shine” alcohol distilled in an automobile radiator (B) An older man with early-stage prostate adenocarci- noma (C) A young adult woman with ␤ -thalassemia (D) An older woman who uses analgesics for chronic headaches (E) A middle-aged woman with her first episode of a urinary tract infection which is associated with py- uria, flank pain, and fever but responds well to a short course of oral antibiotics IX-16. A 45-year-old woman with long-standing systemic lupus erythematosus (SLE) who has had intermittent bouts of acute renal failure over the past 6 years presents with anorexia. Physical examination is noncontributory. Laboratory evaluation includes hematocrit 29%, white count 5000 with a normal differential, and platelet count 27,500/ ␮ L. Renal biopsy shows sclerosis of 14/15 glo- meruli, tubular atrophy, and interstitial fibrosis. The fol- lowing values are also found: Serum electrolytes (mmol/L): Na 136; K 6; Cl 90; ϩϩϪ HCO 20 Ϫ 3 BUN: 35.5 mmol/L (100 mg/dL) Serum creatinine: 665 ␮ mol/L (7.5 mg/dL) Anti-double-strand DNA and C3 levels have been sta- ble. Renal biopsy shows obliterative sclerosing glomeru- lar lesions. The most appropriate management strategy would be (A) high-dose intravenous methylprednisolone (B) high-dose intravenous methylprednisolone and aza- thioprine (C) high-dose intravenous methylprednisolone and in- travenous cyclophosphamide (500 mg/m ) 2 (D) intravenous cyclophosphamide (500 mg/m ) plus 2 low-dose prednisone (E) dialysis IX-17. A 30-year-old woman with diabetic nephropathy received a cadaveric renal allograft. On the third post- operative day her serum creatinine concentration was 160 ␮ mol/L (1.8 mg/dL). She is being treated with cyclosporine and prednisone. On the sixth postoperative day she experiences a decrease in urine output from 1500 mL/d to 1000 mL/d; the serum creatinine concen- tration increases to 194 ␮ mol/L (2.2 mg/dL). Her blood pressure remains stable at 170/90 mmHg, and her tem- perature is 37.2ЊC(99ЊF). The best initial step in manage- ment would be to (A) decrease the dose of cyclosporine (B) obtain ultrasonography of the renal allograft (C) obtain a biopsy of the renal allograft (D) administer pulsed steroid therapy (E) administer an intravenous bolus of furosemide IX-18. A 55-year-old man undergoes intravenous pyelog- raphy (IVP) as part of a workup for hypertension. A 3-cm solitary radiolucent mass is noted in the left kidney; the study otherwise is normal. The man complains of no symptoms referable to the urinary tract, and examination of urinary sediment is within normal limits. Which of the following studies should be performed next? IX. D ISORDERS OF THE K IDNEY AND U RINARY T RACT — Q UESTIONS 201 IX-18. (Continued) IX-20. (Continued) (A) Repeat IVP in 6 months (B) Early-morning urine collections for cytology (three samples) (C) Selective renal arteriography (D) Renal ultrasonography (E) CT scanning (with contrast enhancement) of the left kidney IX-19. A previously healthy 45-year-old man who devel- oped weight gain, fatigue, and vomiting within the past week presents to his physician. He had been seen 3 months earlier for a routine checkup, at which time a physical examination, complete blood count, and serum chemistries were all normal. Relevant physical findings now include blood pressure of 155/110 mmHg and peri- orbital edema. Serum studies reveal a BUN of 30 mmol/ L (85 mg/dL) and a creatinine of 796 ␮ mol/L (9 mg/dL). Urinalysis reveals 2ϩ proteinuria and a microscopic ex- amination of the sediment is depicted below. Which of the following statements is correct? (A) Renal biopsy is indicated (B) The clinical scenario is typical of a patient who presents with IgA nephropathy (C) Extracapillary proliferation is probable (D) Complete spontaneous resolution of the renal dis- ease is likely (E) A trial of high-dose glucocorticoids is contraindi- cated IX-20. Which of the following is a risk factor for carci- noma of the bladder? (A) Exposure to alcohol intake (B) Use of cyclophosphamide (C) History of renal carcinoma (D) Positive family history (E) Infestation with Schistosoma mansoni IX-21. A 10-year-old girl complaining of profound weak- ness, occasional difficulty walking, and polyuria is brought to the pediatrician. Her mother is sure the girl has not been vomiting frequently. The girl takes no medicines. She is normotensive, and no focal neurologic abnormali- ties are found. Serum chemistries include sodium 142 mmol/L, potassium 2.5 mmol/L, bicarbonate 32 mmol/L, and chloride 100 mmol/L. A 24-h urine col- lection on a normal diet reveals sodium 200 mmol/d, po- tassium 50 mmol/d, and chloride 30 mmol/d. Renal ultra- sound demonstrates symmetrically enlarged kidneys without hydronephrosis. A stool phenolphthalein test and a urine screen for diuretics are negative. Plasma renin lev- els are found to be elevated. Which of the following con- ditions is most consistent with the above data? (A) Conn’s syndrome (B) Chronic ingestion of licorice (C) Bartter’s syndrome (D) Wilms’ tumor (E) Proximal renal tubular acidosis IX-22. Normal serum complement levels would be seen in patients with hematuria, proteinuria, and hypertension re- sulting from which of the following? (A) Mixed essential cryoglobulinemia (B) Hepatitis C– associated membranoproliferative glo- merulonephritis (C) Diffuse proliferative lupus nephritis (D) Henoch-Scho¨nlein purpura (E) Poststreptococcal glomerulonephritis IX-23. In acute renal failure, dietary protein should be re- stricted in which of the following? (A) All patients (B) All patients with BUN Ͼ100 (C) All patients with creatinine Ͼ10 (D) Only in patients who are well nourished on hospi- tal admission (E) If azotemia is advanced and dialysis is not an op- tion IX. D ISORDERS OF THE K IDNEY AND U RINARY T RACT — Q UESTIONS 202 IX-24. A 43-year-old homeless man is brought into the emergency room. His past med- ical history is significant for a long history of alcohol abuse. He is found obtunded with evidence of clumsiness on neurologic examination. The emergency medical services who brought the man to the emergency room believed that he had been drinking ethylene glycol. Which set of laboratory values is most likely associated with the above clinical scenario? Na ϩ K ϩ Cl Ϫ HCO 3 Ϫ pH (Serum, mmol/L) Serum Creatinine, ␮ mol/L (mg/dL) Arterial Urine (A) 140 2.5 114 14 265 (3.0) 7.30 6.2 (B) 139 6.3 108 19 265 (3.0) 7.35 5.0 (C) 139 5.1 104 21 265 (3.0) 7.37 5.0 (D) 143 4.8 100 10 265 (3.0) 7.25 5.0 (E) 135 4.5 107 21 265 (3.0) 7.37 5.0 IX-25. A 53-year-old woman with longstanding depression and a history of rheumatoid arthritis is brought in by her daughter, who states that she found an empty bottle of acetylsalicylic acid by her mother’s bedside. The patient is found confused and lethargic and unable to provide a definitive history. What is the most likely set of laboratory values? Na ϩ K ϩ Cl Ϫ HC O 3 Ϫ Room Air ABG (Serum, mmol/L) Serum Creatinine ␮ mol/L (mg/dL) P O 2 P CO 2 pH (A) 140 3.9 85 26 141 (1.6) 100 40 7.40 (B) 140 3.9 85 16 141 (1.6) 100 20 7.40 (C) 140 5.8 100 20 141 (1.6) 100 34 7.38 (D) 150 2.9 100 36 141 (1.6) 80 46 7.50 (E) 116 3.7 85 22 141 (1.6) 80 46 7.50 IX-26. A 37-year-old man is admitted with confusion. Physical examination shows a blood pressure of 140/70 with no orthostasis, normal jugular venous pressure, and no edema. Serum chemistries are notable for sodium 120 mmol/L, K 4.2 mmol/L, bicarbonate 24 mmol/L, ϩ and uric acid 0.177 mmol/L (2 mg/dL). The most likely diagnosis is (A) hepatic cirrhosis (B) cerebral toxoplasmosis with SIADH (C) Addison’s disease (D) significant gastrointestinal fluid loss (E) congestive heart failure IX-27. A 56-year-old diabetic woman with end-stage renal disease (ESRD) has been treated with peritoneal dialysis (prescription of four 2-L exchanges per day) for 6 years. She is 5 ft. 6 in. tall and weighs 70 kg (154 lb). The patient complains of anorexia, abdominal discomfort, fatigue, and insomnia. Medications include erythropoietin, cal- cium carbonate, metoprolol, and a water-soluble vitamin supplement. Laboratory studies are notable for hematocrit 38%, BUN 56 mg/dL, bicarbonate 14 meq/L, calcium 10.4 mg/dL, and phosphate 2.3 mg/dL. IX-27. (Continued) The most likely diagnosis is (A) mycobacterial peritonitis (B) dialysis disequilibrium (C) uremia (D) peritoneal carcinomatosis (E) diabetic ketoacidosis IX-28. Which of the following maneuvers may lead to the development of hyperammonemia? (A) Protein restriction (B) A branched-chain amino acid –enriched protein mixture (C) The use of neomycin (D) The use of lactulose (E) The use of loop diuretics IX-29. Nephrocalcinosis can be associated with (A) the routine use of calcium-based phosphate binders (B) the routine use of aluminum-based phosphate bind ers (C) calcitonin-related peptide IX. D ISORDERS OF THE K IDNEY AND U RINARY T RACT — Q UESTIONS 203 IX-29. (Continued) IX-33. (Continued) (D) secondary hyperparathyroidism (E) Crohn’s disease IX-30. A 35-year-old man is in your clinic with the chief complaint of progressive lower extremity edema. On lab oratory analysis he is found to have a 24-h urine collection that is significant for 5.3 g of protein. Which of the fol- lowing statements is true? (A) Lower serum lipid levels (B) An elevated serum calcium value is likely to be obtained (C) The patient has an increased risk of a hemorrhage (D) The most likely etiology is IgA glumerulonephritis (E) The patient has an elevated thyroxin level IX-31. A 60-year-old man with alcoholism presents to the emergency department with severe confusion, vomiting, and tachycardia. Blood pressure is 90/60, heart rate is 110, and respiratory rate is 32. Laboratory studies are remark- able for the following (mmol/L): Na 128, K 3.9, Cl ϩϩϪ 90, bicarbonate 6. BUN was 12 mg/dL, and creatinine was 2.9 mg/dL. Acetest is negative. Urinalysis shows 4ϩ cal- cium oxalate crystals. The most likely diagnosis is (A) alcoholic rhabdomyolysis with acute tubular necrosis (B) alcoholic ketoacidosis (C) renal tubular acidosis type 1 (D) ingestion of ethylene glycol (E) alcoholic hepatitis with pancreatitis and multiple organ dysfunction IX-32. A 72-year-old man develops acute renal failure af- ter cardiac catheterization. Physical examination is nota- ble for diminished peripheral pulses, livedo reticularis, ep- igastric tenderness, and confusion. Laboratory studies include (mg/dL) BUN 131, creatinine 5.2, and phosphate 9.5. Urinalysis shows 10 to 15 WBC, 5 to 10 RBC, and one hyaline cast per high-power field (HPF). The most likely diagnosis is (A) acute interstitial nephritis caused by drugs (B) rhabdomyolysis with acute tubular necrosis (C) acute tubular necrosis secondary to radiocontrast exposure (D) cholesterol embolization (E) renal arterial dissection with prerenal azotemia IX-33. The hyperlipidemia of nephrotic syndrome is char- acterized by (A) elevation of all plasma lipids but no increase in atherogenesis (B) elevation of total cholesterol but no increase in atherogenesis (C) selective elevation of low-density lipoprotein (LDL) cholesterol with increased atherogenesis (D) no response to HMG-CoA reductase inhibitors (E) myositis in 20% of patients treated with lipid-low- ering agents IX-34. ACE inhibitors would be expected to slow the pro- gression of renal insufficiency in which of the following conditions? (A) Analgesic nephropathy (B) Contrast dye– associated nephropathy (C) Chronic glomerulonephritis with Ͼ1 g/d protein- uria (D) Autosomal dominant polycystic kidney disease (ADPKD) (E) Amphotericin-induced nephropathy IX-35. Which of the following statements about polycystic kidney disease is true? (A) Polycystic kidney disease is an autosomal reces- sive disorder linked to a causative gene on the short arm of chromosome 16. (B) Erythropoietin levels are often low due to progres- sive renal failure. (C) Chronic diverticular disorder is a rare finding. (D) Nephrotic-range proteinuria is an uncommon find- ing. (E) The development of an intracranial saccular aneu- rysm (berry aneurysm) is associated with renal failure and does not have a specific association with polycystic kidney disease. IX-36. Which of the following medications commonly does not cause hypokalemia? (A) ␤ -Adrenergic agonists (B) Theophylline (C) Calcium channel blockers (D) Diuretic therapy (E) Amphotericin B IX-37. In patients with urinary incontinence, which con- dition puts them at highest risk for the development of hydronephrosis? (A) Alzheimer’s disease (B) Guillain-Barre´ syndrome (C) Normal-pressure hydrocephalus (D) Low-grade astrocytoma (E) Hypothyroidism IX-38. Which of the following genetic abnormalities is as- sociated with the development of hyperkalemia? (A) 11 ␤ -hydroxylase deficiency IX. D ISORDERS OF THE K IDNEY AND U RINARY T RACT — Q UESTIONS 204 IX-38. (Continued) (B) Liddle’s syndrome (C) Bartter’s syndrome (D) Gitelman’s syndrome (E) Autosomal dominant polycystic kidney disease IX-39. Which of the following statements is true concern- ing acute poststreptococcal glomerulonephritis (PSGN)? (A) The latent period appears to be longer when PSGN is associated with cutaneous rather than pharyngeal infections. (B) Serologic evidence of a streptococcal infection can usually be found regardless of antimicrobial ther- apy. (C) Antimicrobial therapy for streptococcal infection is without value once the presence of renal disease is established. (D) Long-term antistreptococcal prophylaxis is indi- cated after a prior documented case of PSGN. (E) Progressive deterioration in renal function is more common in children than in adults with PSGN. IX-40. A 19-year-old man arrives in your office complain- ing of generalized weakness, nausea, vomiting, and mal- aise. He states the color of his urine over the past several days has turned a “red,” or “smoky” color. He states that he was well until approximately 10 days prior to his visit, when he had severe pharyngitis with a high-grade fever, although his pharyngitis and fever have now resolved. Physical examination reveals a blood pressure of 180/96, pulse of 98, and a temperature of 37.1ЊC (98.7ЊF). Lab- oratory values reveal a serum creatinine of 177 ␮ mol/L (2 mg/dL). Which of the following statements is true? (A) The presence of dysmorphic red blood cells with red blood cell casts and leukocyte casts on micro- scopic examination is a universal finding. (B) A 24-h urine collection reveals 4 g of protein. (C) Mixed cryoglobulinemia is an unusual finding. (D) The levels of serum C3 and CH50 are usually within normal limits. (E) Electron microscopy typically reveals large elec- tron-dense immune deposits in the subendothelial, subepithelial, and mesangial areas. IX-41. Diseases involving the renal glomeruli are fre- quently encountered. Both humoral and cellular mecha- nisms play a part in the pathogenesis of glomerular injury. Which of the following glomerular diseases is associated with glomerulosclerosis as opposed to cellular prolifera- tion? (A) IgA nephropathy (B) Diabetic nephropathy (C) Poststreptococcal glomerulonephritis (D) Henoch-Scho¨nlein purpura (E) Glomerulonephritis related to hepatitis C infection IX-42. An 87-year-old man presents to the emergency room obtunded. On physical examination he has a pulse of 120, blood pressure of 142/80, and weight of 72 kg (158 lb). He has diminished skin turgor and dry mucous membranes. He also has a fever of 38.9ЊC (102.0ЊF). Lab- oratory analysis reveals the following results: Serum electrolytes (mmol/L): Na 164; K 4.6; ϩϩ Cl 108; HCO 26 ϪϪ 3 BUN: 17.1 mmol/L (48 mg/dL) Serum creatinine: 168 ␮ mol/L (1.9 mg/dL) The most appropriate treatment plan would be which of the following? (A) D W at 300 mL/h 5 (B) D half-normal saline at 300 mL/h 5 (C) D W at 150 mL/h 5 (D) D W at 75 mL/h 5 (E) Ringer’s lactate at 160 mL/h IX-43. A 48-year-old woman is hospitalized for elective knee surgery. Routine preoperative laboratory evaluation reveals the following: Serum electrolytes (mmol/L): Na 138; K 3.5; ϩϩ Cl 110; HCO 20 ϪϪ 3 Blood glucose: 5.2 mmol/L (95 mg/dL) Serum creatinine: 160 ␮ mol/L (1.8 mg/dL) BUN: 7.1 mmol/L (20 mg/dL) Urinalysis: pH 5.2; specific gravity 1.005; protein 1ϩ; glucose 2ϩ; 3 to 5 white blood cells per high-power field The patient states that she voids several times during the night but is unaware of any problem with her kidneys. Which of the following disorders would be most likely associated with the findings in this case? (A) Multiple myeloma (B) Diabetic nephropathy (C) IgA nephropathy (D) Penicillamine-induced nephropathy (E) Lupus nephritis IX-44. A 45-year-old woman presents with the third epi- sode of nephrolithiasis. Laboratory studies disclose the following: Serum electrolytes (mmol/L): Na 134; K 2.5; ϩϩ Cl 106; HCO 18 ϪϪ 3 Serum chemistries: creatinine 97 ␮ mol/L (1.1 mg/dL); calcium 2.4 mmol/L (9.5 mg/dL); albumin 40 g/L (4.0 g/dL) Arterial blood gas values: P 4 kPa (30 mmHg); CO 2 P 14 kPa (108 mmHg); pH 7.30 O 2 Urine pH: 7.2 A plain film of the abdomen is shown below. Which of the following statements about this clinical picture is cor- rect? IX. D ISORDERS OF THE K IDNEY AND U RINARY T RACT — Q UESTIONS 205 IX-44. (Continued) IX-46. (Continued) (A) The findings are consistent with the presence of multiple myeloma. (B) The findings are consistent with the presence of medullary sponge kidney. (C) There is evidence of type I distal renal tubular aci- dosis (RTA). (D) Family members are typically not affected. (E) Intravenous pyelography is typically unremarkable. IX-45. Which of the following statements is correct re- garding renal transplantation? (A) A potential living donor who does not share the same blood type as the recipient cannot be consid- ered even if the tissue types are HLA-identical. (B) The degree of HLA mismatch with cadaveric do- nor kidneys is a determinant of long-term graft survival. (C) Progressive renal failure in a transplant recipient, termed chronic rejection, is not associated with re- nal vascular damage. (D) Allopurinol must be coadministered with azathio- prine to prevent urate nephropathy associated with drug-induced cell turnover. (E) Cyclosporine inhibits interleukin (IL) 2 production by cytotoxic (CD8ϩ) T cells. IX-46. A 45-year-old man with a diagnosis of ESRD sec- ondary to diabetes mellitus is being treated with peritoneal dialysis. This is being carried out as a continuous ambu- latory peritoneal dialysis (CAPD). He undergoes four 2-L exchanges per day and has been doing so for approx- imately 4 years. Complications of peritoneal dialysis in- clude which of the following? (A) Hypotension after drainage of dialysate (B) Hypoalbuminemia (C) Hypercholesterolemia (D) Hypoglycemia (E) Pleural effusion IX-47. A 45-year-old woman with a long history of asthma now presents with progressive lower extremity skin rash as well as renal insufficiency. On physical examination she is short of breath, with audible wheezing. Her skin examination reveals numerous raised papules, which are erythematous in color, on both lower extremities. The le- sions are nonblanching and raised, with areas of necrosis. Which of the following statements is correct? (A) The peripheral white blood count is within normal limits. (B) Antineutrophilic cytoplasmic autoantibodies (ANCA) are found in a cytoplasmic distribution consistent with antiproteinase-3 (PR3-ANCA). (C) A history of a progressive lower extremity neurop- athy is a rare finding. (D) A normal chest x-ray is a typical finding. (E) Patient has a history of coronary disease. IX-48. You are called to see a 62-year-old man who has recently undergone a transurethral resection of his pros- trate. Postoperatively he is found to be confused and stu- porous. The patient interoperatively received4Lof5% dextrose as intravenous fluids. Clinically he is euvolemic with a blood pressure of 142/82 mmHg. He weighs 68 kg. Serum electrolytes (mmol/L) are obtained, which reveal Na 114 and K 3.8, and serum osmolality is 230. The ϩϩ correct management decision would be which one of the following? (A) Free water restriction (B) Normal saline at a rate of 180 mL/h for 3 h then reevaluate with repeat serum chemistries (C) 3% saline at 90 mL/h for 3 h and reevaluate with repeat serum chemistries (D) 3% saline at 180 mL/h for 3 h and reevaluate with repeat serum chemistries (E) Normal saline at 90 mL/h for 3 h and reevaluate with repeat serum chemistries IX-49. A 45-year-old patient with membranous glomeru- lonephritis and renal insufficiency has nephrotic-range proteinuria. On physical examination the patient has 3ϩ lower extremity edema, and the patient’s serum albumin is 21 g/L (2.1 g/dL) and serum creatinine is 106 ␮ mol/L (1.2 mg/dL). An attempt to improve the lower extremity edema is made with the oral loop diuretic furosemide. Unfortunately, a poor response is obtained. Which of the following mechanisms likely contributes to the subopti- mal response to diuretics? [...]... occlusion of the retinal vein (D) acute glaucoma (E) Purtscher’s retinopathy X- 26 In which one of the following situations would therapy with oral chenodeoxycholic acid be most effective in dissolving gallstone(s)? (A) A 27-year-old Asian woman with thalassemia (B) A 49-year-old woman with two 2-cm stones (C) A 60 -year-old man with gallstones visible on chest x-ray (D) A 45-year-old woman with a history of. ..2 06 IX DISORDERS OF THE KIDNEY AND URINARY TRACT — QUESTIONS IX-49 (Continued) (A) Decreased renal tubular secretion of furosemide (B) Diminished bioavailability of furosemide (C) Binding of furosemide to albumin in the tubular fluid (D) Decreased proximal reabsorption of sodium (E) Decreased distal reabsorption of sodium IX-50 A 4 6- year-old man with long-standing diabetes mellitus... pressure X- 56 A 40-year-old man has a history of ulcerative colitis Features of his illness that would contribute to an increased risk of developing colon cancer include which of the following? (A) (B) (C) (D) (E) Disease duration of less than 10 years History of toxic megacolon Presence of pancolitis (total colonic involvement) Presence of pseudopolyps on colonoscopy High steroid requirements X-57 Subacute... X-19 For the past 6 months a 50-year-old man has had diarrhea and migratory arthralgias and has lost 9.1 kg (20 lb) An upper gastrointestinal barium study shows a malabsorption pattern in the small bowel Stool fat content is 35 g per 24 h After oral administration of 25 g of D-xylose, a 5-h urine collection contains 0.8 g of X DISORDERS OF THE GASTROINTESTINAL SYSTEM — QUESTIONS X-19 (Continued) D-xylose... Administration of prednisone, 10 mg every other day for 3 months (D) Administration of acyclovir, 400 mg every 6 h for 2 weeks (E) Administration of interferon ␣, 10 million units three times per week for 4 months X- 36 A 64 -year-old man with insulin-dependent adult-onset diabetes mellitus seeks emergency medical treatment after 2 days of increasingly severe abdominal pain in the right upper quadrant that has... high-fat diet (E) 1 g D-xylose in 5-h urine collection after 25 g oral D-xylose X -6 2 A 28-year-old woman complains of chronic diarrhea After a lengthy history and a negative physical examination, you suspect surreptitious laxative abuse Which of the following tests would be most consistent with this hypothesis? (A) (B) (C) (D) (E) Abnormal osmotic gap Fecal leukocytes noted Excess stool fat Charcot-Leyden... count and serum electrolyte concentrations Serum D-xylose concentration is 0. 76 mmol/L (15 mg/dL) 2 h after an oral challenge, and 24-h fecal fat determination is 12 g on a 100-g fat diet A representative biopsy specimen of his jejunum is shown below Which of the following statements about the man’s illness is correct? X-14 A 30-year-old man complains of abdominal cramps, bloating, and diarrhea He believes... completed his run of dialysis and you find him somewhat confused, with a blood pressure of 86/ 42 Which of the following factors most likely contributed to the postdialysis hypotension? (A) (B) (C) (D) (E) Reduced temperature dialysate Concomitant use of antihypertensive therapy Impaired autonomic response Poor dietary intake during dialysis Hyperphosphatemia IX-51 A 4 6- year-old man has long-standing hypertension,... insufficiency of both angiotensin- and adrenal mineralocorticoid-secreting capacity Inhibition of the renin-angiotensin system by ␤-adrenergic blockade such as propranolol can cause hyperkalemia; in addition, nonsteroidal anti-inflammatory agents or angiotensin-converting enzyme (ACE) inhibitors may also lead to hyperkalemia The use of carbenicillin, theophyllin, and hy207 208 IX DISORDERS OF THE KIDNEY... intrahepatic cholestasis 227 X- 36 (Continued) The most appropriate management at this point would be to order X-35 A 35-year-old former hemodialysis nurse is seen because of a 6- month history of fatigue and amenorrhea On examination she has scleral icterus, a mildly tender liver, and a tibial rash consistent with erythema nodosum ALT and AST levels are both in the range of 1.5 ␮kat/L (100 U/L) and bilirubin . (1 .6) 100 20 7.40 (C) 140 5.8 100 20 141 (1 .6) 100 34 7.38 (D) 150 2.9 100 36 141 (1 .6) 80 46 7.50 (E) 1 16 3.7 85 22 141 (1 .6) 80 46 7.50 IX- 26. A 37-year-old man is admitted with confusion. Physical. 14 265 (3.0) 7.30 6. 2 (B) 139 6. 3 108 19 265 (3.0) 7.35 5.0 (C) 139 5.1 104 21 265 (3.0) 7.37 5.0 (D) 143 4.8 100 10 265 (3.0) 7.25 5.0 (E) 135 4.5 107 21 265 (3.0) 7.37 5.0 IX-25. A 53-year-old. mesangial deposition of IgA on immuno- fluorescence (E) deposition of C3 in capillary walls on immunofluo- rescence IX-10. The condition of a 50-year-old obese woman with a 5-year history of mild hypertension