Nephrology

Topics in this chapter

• Acute Kidney Injury
• Acid-Base and Electrolyte Disorders
• Chronic Kidney Disease Complications
• Dialysis and Renal Replacement
• Glomerular Diseases and Syndromes
• Genetic Renal Diseases

Practice questions

1. Question 1Q-09FCBC

   A 45-year-old man with a history of alcohol use disorder is admitted for severe weakness and generalized malaise. Laboratory investigations reveal: Serum Na+ 138 mEq/L, Serum K+ 2.1 mEq/L, Serum Cl- 104 mEq/L, Serum HCO3- 30 mEq/L, and arterial blood gas shows a pH of 7.50. Urinary chloride is measured at 28 mEq/L (normal 10-20 mEq/L). Which of the following is the most likely diagnosis?

   1. A.Bartter syndrome
   2. B.Gitelman syndrome
   3. C.Vomiting / Gastric suction
   4. D.Surreptitious diuretic abuse
   See the answer and solution
2. Question 2Q-F04FFC

   A 32-year-old woman presents with recurrent macroscopic hematuria, typically occurring 1-2 days following upper respiratory tract infections. Her renal function is normal, and she is normotensive. Serum complement levels (C3 and C4) are within normal limits. Which of the following is the gold standard method for definitive diagnosis of her condition?

   1. A.Ultrasonography of kidneys
   2. B.Renal biopsy with immunofluorescence
   3. C.Measurement of serum IgA levels
   4. D.Antinuclear antibody (ANA) titer
   See the answer and solution
3. Question 3Q-732EAE

   A 60-year-old man with a 20-year history of poorly controlled type 2 diabetes mellitus is evaluated for progressive proteinuria. His urine protein-to-creatinine ratio is 3.5 g/g, serum creatinine is 1.4 mg/dL, and blood pressure is 150/95 mmHg. Renal ultrasound shows normal-sized, highly echogenic kidneys. Which of the following is the earliest histological glomerular lesion seen in diabetic nephropathy?

   1. A.Kimmelstiel-Wilson nodules
   2. B.Thickening of the glomerular basement membrane
   3. C.Mesangial cell proliferation
   4. D.Fibrinoid necrosis of afferent arterioles
   See the answer and solution
4. Question 4Q-BF8133

   A 28-year-old man presents with acute onset oliguria, gross hematuria, and severe hypertension 3 weeks after recovering from a skin infection. Laboratory tests reveal elevated anti-streptolysin O (ASO) titers and low serum C3 levels with normal C4 levels. Renal biopsy is performed. Which of the following immunofluorescence findings is most characteristic of this condition?

   1. A.Linear IgG deposition along the GBM
   2. B.Granular IgG and C3 deposition in a 'starry sky' or 'lumpy-bumpy' pattern
   3. C.Dense intramembranous deposits
   4. D.Pauci-immune staining with minimal immune complex deposition
   See the answer and solution
5. Question 5Q-6B3D64

   A 50-year-old man is evaluated for acute kidney injury following a cardiac catheterization procedure. His baseline serum creatinine was 1.0 mg/dL, which has risen to 2.4 mg/dL over 48 hours. Physical examination reveals livedo reticularis on his lower extremities and bilateral Hollenhorst plaques on fundoscopic examination. Urinalysis shows eosinophiluria. Which of the following is the most likely underlying etiology?

   1. A.Radiocontrast-induced nephropathy
   2. B.Atheroembolic renal disease
   3. C.Acute interstitial nephritis from antibiotics
   4. D.Hepatorenal syndrome
   See the answer and solution