Which of the following is listed as a cause of extraglomerular hematuria?

• A. Kidney stone
• B. Renal cell carcinoma
• C. Glomerulonephritis
• D. Nephrotic syndrome

Answer: (A)

Extraglomerular hematuria comes from bleeding sources outside the glomerulus, inside the urinary tract. The classic example among the options is a kidney stone, which can irritate the lining of the kidney, calyces, or ureter as it moves, leading to visible blood in the urine. This type of bleeding is typically non-glomerular in origin and often presents with painless hematuria, sometimes accompanied by colicky flank pain.

In contrast, glomerulonephritis involves the filtering units of the kidney themselves, so the urine often shows dysmorphic red blood cells and sometimes red cell casts, reflecting glomerular injury. Nephrotic syndrome is a glomerular condition characterized by heavy protein loss, edema, and hypoalbuminemia, with hematuria not being the defining feature. Renal cell carcinoma can also cause hematuria if the tumor bleeds into the collecting system, but the most characteristic extraglomerular source listed is a kidney stone.