A 24-year-old woman is dipstick positive for blood in her urine. This is repeated twice between menstrual periods and remains positive. Microscopic evaluation reveals RBCs, some of which are deformed and some in the form of casts. Which of the following is the most likely cause of the hematuria?
High-Yield Explanation
Isolated hematuria is usually of urologic cause (e.g., tumor, trauma, stone) but can also be glomerular in origin. The finding of red cell casts or dysmorphic red cells (best appreciated by phase microscopy) suggests the source of bleeding is glomerular in origin.