PracticeQuestions Flashcards
A 35-year-old man has had fever for the past 5 days. Yesterday he developed difficulty speaking. On physical examination he has petechial hemorrhages on his lower extremities. His temperature is 37.7 C. Laboratory studies show Hgb 8.4 g/dL, Hct 25.9%, MCV 100 fL, platelet count 9000/microliter, and WBC count 9800/microliter. Examination of his peripheral blood smear shows schistocytes. His prothrombin time is 18 seconds and his partial thromboplastin time is 44 seconds. His serum creatinine is 2.6 mg/dL, haptoglobin is 2 mg/dL, and total bilirubin 5.5 mg/dL. He died despite plasmapheresis. At autopsy, platelet thrombi are observed in the small arteries of the kidneys, heart, and brain. Which of the following is the most likely diagnosis?
TTP
A 45-year-old woman has had increasing malaise for the past year. On physical examination her blood pressure is 265/150 mm Hg. Laboratory studies show a plasma renin activity of 9 ng/mL/hr. She then suffers a “stroke” with a right basal ganglia hemorrhage and dies. At autopsy the kidneys are bilaterally small with granular surfaces. Microscopically they show hyperplastic arteriolosclerosis with fibrinoid necrosis, petechial hemorrhages, and microinfarcts in the cortices. Which of the following conditions is most likely to be her underlying cause of death?
A Diabetes mellitus, type II
B Fibromuscular dysplasia
C Factor V Leiden mutation
D Analgesic abuse
E Diffuse scleroderma
E
A clinical study is performed involving subjects with glomerulonephritis. One group of subjects has a diagnosis of crescentic glomerulonephritis and another group has membranous glomerulonephritis. Which of the following laboratory findings is most likely to be found in the absence of other findings in subjects with membranous glomerulonephritis?
A Rapid onset
B Red blood cell casts
C Oliguria
D Albuminuria
E Hypertension
d
A 50-year-old man is hospitalized for acute myocardial infarction. He has decreased cardiac output with hypotension requiring multiple pressor agents. His urine output drops over the next 3 days. His serum urea nitrogen increases to 59 mg/dL, with creatinine of 2.9 mg/dL. Urinalysis reveals no protein or glucose, a trace blood, and numerous hyaline casts. Five days later, he develops polyuria and his serum urea nitrogen declines. Which of the following pathologic findings in his kidneys is most likely to have caused his azotemia?
A Patchy tubular necrosis
B Fusion of podocyte foot processes
C Glomerular crescents
D Hyperplastic arteriolosclerosis
E Mesangial immune complex deposition
(A) CORRECT. He has findings of ischemic acute tubular necrosis from heart failure with hypotension. A clue is the >20:1 ratio of urea nitrogen to creatinine, which occurs early in the course, from prerenal azotemia. As the disease progresses, the ratio begins to approach 10:1, typical for renal diseases. ATN may also be produced by toxins such as ethylene glycol in antifreeze.
A 20-year-old previously healthy man has been feeling tired for the past 5 days. He goes to his physician when he passes dark-colored urine. On physical examination his blood pressure is 155/90 mm Hg. Labortory studies show his serum creatinine is 4.4 mg/dL. A urinalysis reveals pH 6, specific gravity 1.011, 3+ blood, 1+ protein, no glucose, and no ketones. On urine microscopic examination there are numerous RBC casts. Which of the following pathologic findings on renal biopsy is most likely to be present in this man?
A Glomerular crescents
B Widened proximal tubules
C Polymorphonuclear infiltrates
D Lipiduria
E IgA deposited in glomerular capillaries
A
Crescents are characteristic for a rapidly progressive glomerulonephritis; they form when there is leakage of fibrinogen into Bowman’s space, with proliferation of epithelial cells to form the crescent.
A 70-year-old woman has had a fever for the past 3 days. She has burning dysuria. On physical examination her temperature is 37.8 C and there is dull pain on palpation of her left lower back. Laboratory studies show Hgb 13.3 g/dL, Hct 40.2%, MCV 86 fL, platelets 222,000/microliter, and WBC count 12,300/microliter with differential count 72 segs, 9 bands, 13 lymphs, 5 monos, and 1 eosinophil. A urine dipstick analysis shows sp gr. 1.017, pH 6, leukocyte esterase positive, nitrite positive, protein negative, glucose negative, and blood negative. Which of the following microscopic urinalysis findings would be most diagnostic for her renal disease?
A Broad renal casts
B Oval fat bodies
C Renal tubular epithelial cells
D White blood cell casts
E Triple phosphate crystals
D
The WBC casts are most characteristic for an acute interstitital nephritis (acute pyelonephritis).
A 25-year-old woman has been hospitalized for treatment of a Staphylococcus aureus abscess of her left thigh complicating a puncture wound. The wound is incised and drained and she receives antibiotic therapy. She is improving and discharged home a week later, but the next day she develops a fever. On physical examination her temperature is 38.1 C and there is a diffuse erythematous skin rash of her trunk and extremities. A urinalysis shows sp gr 1.020, pH 6.5, 1+ blood, 1+ protein, no glucose, and no ketones. There are 10-20 WBCs/hpf and 1-5 RBCs/hpf, and a few eosinophils are noted on urine microscopic examination. Which of the following is the most likely diagnosis?
A Acute tubular necrosis
B Analgesic abuse nephropathy
C Drug-induced interstitial nephritis
D Hemolytic-uremic syndrome
E Post-infectious glomerulonephritis
F Urinary tract infection
C
A 55-year-old man has had dysuria for the past week. Over the past 2 days he has experienced shaking chills. On physical examination his temperature is 39.3 C.. A urinalysis shows sp gr 1.016, pH 6, 1+ glucose, 1+ blood, no ketones, and no protein. Urine microscopic examination shows numerous WBCs and WBC casts. His serum creatinine is 1.5 mg/dL and glucose 155 mg/dL with hemoglobin A1C 8.7%. A renal ultrasound scan shows a 0.3 cm free floating echodense object in the left renal pelvis. Which of the following complications has this man most likely developed?
A Acute tubular necrosis
B Aspergillus fungus ball
C Cystine calculus
D Hematoma
E Papillary necrosis
F Renal cell carcinoma
G Urothelial carcinoma
(E) CORRECT. Papillary necrosis is a renal complication of diabetes mellitus, as in this case. Papillary necrosis may also be seen with analgesicc abuse nephropathy, with sickle cell anemia, and with a severe acute pyelonephritis.
A 30-year-old man has had increasing malaise with fever, abdominal pain, and weight loss of 3 kg over the past 3 weeks. On physical examination his blood pressure is 160/110 mm Hg. He has a stool positive for occult blood. A urinalysis reveals hematuria but no proteinuria or glucosuria. He has no serum anti-neutrophil cytoplasmic autoantibodies and his antinuclear antibody test is negative. Aneurysmal arterial dilations and occlusions are seen in the medium sized renal and mesenteric arteries with angiography. He improves with corticosteroid therapy. Which of the following is the most likely diagnosis
A Benign nephrosclerosis
B Fibromuscular dysplasia
C Nodular glomerulosclerosis
D Polyarteritis nodosa
E Systemic lupus erythematosus
F Thrombotic microangiopathy
G Wegener granulomatosis
D
A 69-year-old woman with Parkinson disease dies from pneumonia. She was treated for hypertension for the past 10 years of her life. Just prior to death her serum urea nitrogen was 15 mg/dL. At autopsy her slightly small kidneys have a granular surface. On microscopic examination the kidneys show scattered hyalinized glomeruli, interstitial fibrosis with focal tubular atrophy, and arteriolar thickening. Which of the following renal diseases is most likely to be present?
A Nodular glomerulosclerosis
B Hyperplastic arteriolosclerosis
C Analgesic abuse nephropathy
D Benign nephrosclerosis
E Chronic pyelonephritis
d
A 46-year-old African-American man dies suddenly, and the medical examiner peforms an autopsy. She finds a large right basal ganglia hemorrhage. There is arteriosclerosis of small cerebral arterial branches. Which of the following pathologic findings is most likely to be present in this man’s kidneys?
A Fibromuscular dysplasia of the renal artery
B Vasculitis with mononuclear cell infiltrates
C A linear pattern of glomerular capillary IgG deposition by immunofluorescence
D Arteriolar fibrinoid necrosis with microhemorrhages
E Nodular and diffuse glomerulosclerosis
(D) CORRECT. The findings point to malignant hypertension, and arteriolar fibrinoid necrosis with small hemorrhages is most typical.
A 70-year-old has had increasing lethargy for the past 5 years. There are no remarkable physical examination findings. Laboratory studies have shown that his serum creatinine has risen from 1.9 to 6.6 mg/dL over that time. He also has ischemic heart disease. Following an episode of severe angina, he became hypotensive for 12 hours. Following this episode he was placed on hemodialysis. Which of the following laboratory test findings is most characteristic for his underlying disease process leading to chronic renal failure?
A Hypergammaglobulinemia
B Anti-glomerular basement membrane antibody
C Elevated hemoglobin A1C
D Increased prostate specific antigen
E High anti-streptolysin O titer
(C) CORRECT. Diabetic nephropathy leads to progressive renal failure over many years. Diabetes mellitus with advanced atherosclerosis accounts for his ischemic heart disease.
A 65-year-old woman has had increasing malaise for the past 6 months. On physical examination she has a blood pressure of 145/95 mm Hg. Laboratory studies show her serum creatinine is 3.5 mg/dL. A renal scan reveals bilateral small, shrunken kidneys. Her serum creatinine continues to rise. 5 years later she receives a cadaveric renal transplant. She initially does well, but two years later she now has slow and progressive loss of renal function with diminished renal blood flow in the transplant kidney. What is the most probable cause for her loss of renal function following the transplant procedure?
A Lupus nephritis
B Amyloidosis
C Chronic rejection
D Urate nephropathy
E Microscopic polyangiitis
c
Slow and progressive loss of renal transplant function suggests chronic rejection, which results from vascular sclerosis. This is not treatable by pharmacologic therapy. Another transplant or hemodialysis will be necessary. However, on average, most renal allografts function for over 20 years.
A 31-year-old man has noted increased swelling of his feet over the past month. On physical examination he is afebrile but his blood pressure is 140/90 mm Hg. There is 2+ pitting edema to his knees. A urinalysis reveals 4+ proteinuria but no hematuria or glucosuria. No WBCs or RBCs are seen on microscopic urinalysis. He receives a course of corticosteroid therapy and does not improve. Over the next 3 years his serum urea nitrogen and creatinine become increasingly elevated. He requires hemodialysis. He then receives a cadaveric renal transplant which functions well for 18 months, but then the proteinuria recurs, and progressive renal failure ensues. Which of the following conditions is most likely to produce these findings?
A Focal segmental glomerulosclerosis
B Goodpasture syndrome
C Minimal change disease
D IgA nephropathy
E Systemic lupus erythematosus
(A) CORRECT. FSGS recurs in about a fourth of cases with renal transplant. FSGS has a 50% chance for end stage renal failure in 10 years following diagnosis.
A 29-year-old woman has developed a fever over the past week along with pleuritic chest pain. On physical examination her temperature is 37.5 C. Laboratory studies show her serum creatinine is 2.7 mg/dL with urea nitrogen 25 mg/dL. Microscopic urinalysis reveals numerous RBC, WBC, and granular casts. She has decreased serum levels of both C3 and C4 complement. A renal biopsy is performed. By light microscopy there are thickened capillary loops and mesangial proliferation in all glomeruli. Deposition of IgG and C3 in the glomerular basement membrane is seen by immunofluorescence. By electron microscopy there are epimembranous, subendothelial, and mesangial electron dense deposits. Which of the following is the most likely diagnosis?
SLE
The findings fit with a proliferative glomerulonephritis with extensive immune complex deposition, typical for lupus nephritis. She would most likely have a positive ANA. Lupus nephritis commonly complicates SLE and can lead to the presence of a urine with many cells and casts.
