Renal Pathology — Past Paper OmpathStudy

renal pathology — Questions and Answers Complete review bank: 45 questions recovered from all 30 source pages. 1. A 53-year-old man has passed darker urine for the past week. On physical examination there are no abnormal findings. A urinalysis shows pH 5.5, specific gravity 1.013, 2+ blood, no protein, and no glucose. A urine cytology is performed and there are atypical cells seen. A cystoscopy is performed, but no mucosal lesions are noted. He has a 60 pack year history of smoking cigarettes. Which of the following is the most likely diagnosis? A. Adenocarcinoma of prostate B. Urothelial carcinoma of renal pelvis C. Acute interstitial nephritis D. Nodular glomerulosclerosis E. Squamous cell carcinoma of penis Answer: B. The lack of findings in the bladder, but the presence of atypical cells along with hematuria suggests that there is a malignant lesion and it is located higher in the urinary tract. His history of smoking increases the risk for urothelial carcinomas and for renal cell carcinomas. 2. A 62-year-old man has had back pain for the past 8 months. He has had a productive cough for the past 2 days. On physical examination his temperature is 39°C and there is dullness to percussion at the right lung base. Laboratory studies show 4+ gram-positive diplococci in the sputum. A chest radiograph shows right lower lobe consolidation. An abdominal CT scan shows multiple lytic lesions of the vertebrae. On the day prior to death his serum urea nitrogen was 63 mg/dL with creatinine 7.1 mg/dL. A dipstick urinalysis was normal. At autopsy, his kidneys are firm and pale. Microscopically, there is abundant pink hyaline material in glomeruli and around small vessels. This material stains positively with Congo red. Which of the following laboratory findings was most likely to have been present in this patient in the week prior to death? A. Positive antinuclear antibody test B. Serum glucose of 210 mg/dL C. CD4 lymphocyte count of 110/microliter D. Total serum protein of 9.2 g/dL E. Serum prostate specific antigen of 11.8 ng/mL Answer: D. The findings are consistent with renal amyloid deposition with multiple myeloma. The total protein is elevated from increased serum monoclonal immunoglobulin. Myeloma can produce lytic bone lesions and patients often develop infections with encapsulated bacteria. The excessive light chain production leads to AL amyloid deposition. Bence-Jones proteinuria is often present, but the urine dipstick is most sensitive for albumin, not globulins. 3. A 52-year-old previously healthy man has experienced episodes of discomfort with urination for 3 months. There are no remarkable findings on physical examination. Laboratory studies include a urinalysis that reveals 1+ blood. Microscopic urine examination shows numerous RBCs, a few WBCs, and no casts. A urine culture is negative. A plain film radiograph of the pelvis shows a rounded, 1 cm radiopaque lesion in the region of the bladder. Which of the following laboratory test findings is most likely to be present in this man? A. Albuminuria B. Hypercalciuria C. Transaminasemia D. Hemoglobinuria E. Hyperuricemia Answer: B. The findings suggest a bladder calculus. Most stones are composed of calcium with oxalate or phosphate. The calcium content makes them radiopaque, unlike pure uric acid stones that are often radiolucent (by conventional x-ray) and which are not very common. The most common cause for urinary tract calculi is idiopathic hypercalciuria. 4. A 72-year-old man has been feeling tired and lethargic for 5 months. He has noted increasing hesitancy with urination. On physical examination his prostate is diffusely enlarged. Laboratory studies show sodium 139 mmol/L, potassium 4.0 mmol/L, chloride 104 mmol/L, bicarbonate 25 mmol/L, creatinine 3.9 mg/dL, and glucose 81 mg/dL. Which of the following renal abnormalities is most likely to be present in this man? A. Cortical atrophy B. Glomerulonephritis C. Papillary necrosis D. Polycystic change E. Renal cell carcinoma Answer: A. The prostatic hyperplasia could lead to obstructive uropathy with bilateral hydronephrosis, renal cortical atrophy, and eventual chronic renal failure. His elevated serum creatinine is evidence for reduced renal function. 5. A 36-year-old woman has urinary frequency with dysuria for the past 4 days. On physical examination she has no flank pain or tenderness. A urinalysis reveals sp. gr. 1.014, pH 7.5, no glucose, no protein, no blood, nitrite positive, and many WBC's. She has a serum creatinine of 0.9 mg/dL. Which of the following is the most likely diagnosis? A. Lupus nephritis B. Urinary lithiasis C. Acute cystitis D. Malakoplakia E. Urothelial carcinoma Answer: C. These are features of acute inflammation. There are no casts, because the infection involves just the bladder, though such an infection could ascend to produce pyelonephritis. Urinary tract infections are more common in women because of the shorter urethra. The positive nitrate occurs with the most common