In the workup of extraglomerular hematuria, which test is used to rule out infection?

• A. Noncontrast CT
• B. Urine cytology
• C. Urine culture
• D. Cystoscopy

Answer: (C)

Ruling out infection is best approached with urine culture because it directly detects bacteria in the urine, quantifies bacteriuria, and helps guide antibiotic therapy. This makes it the test of choice when infection could explain extraglomerular hematuria. Noncontrast CT is aimed at stone disease, not infection; urine cytology screens for malignant cells in the urine; cystoscopy visually inspects the bladder and upper urinary tract but does not diagnose infection. If the culture grows bacteria, infection is responsible and can be treated; if it’s negative, infection is less likely and other causes of hematuria can be investigated.