Clinical importance of microhematuria.

To evaluate the etiology of microhematuria, the cases of 200 consecutive patients with asymptomatic microhematuria who had undergone complete urologic examination and two-year follow-up were reviewed. Most patients were 50 to 59 years old. Highly significant urologic lesions were found in 20% of patients. Thirteen percent of these patients had a genitourinary malignant neoplasm. No urologic lesion could be identified in 19% of patients in this group. The results suggest that present diagnostic modalities have substantially refined and improved the urologist's diagnostic abilities. The urologic examination of patients with asymptomatic microhematuria, particularly in those older than 40 years, is justified.