Unexplained hematuria.

In 270 consecutive patients who presented with hematuria over a 12-month period, complete visualization of the urinary tract by urography and cystoscopy indicated a causative lesion in over 90%. Where a cause could not be found on the first presentation, the initial evaluation was repeated within 4 months, revealing the previously missed diagnoses in four patients. Of patients who bled while receiving anticoagulants, 17% were found to have an important underlying cause other than anticoagulant therapy. Despite repeated evaluation, and in many instances more elaborate investigation with angiography, computerized tomography and ultrasonography, no reasonable diagnosis could be made in 6% (12% of those with microscopic hematuria, 4% with gross hematuria). One hundred and fifty-nine patients with unexplained hematuria, seen between 1975 and 1983, were studied. The triad of "gross, total and painless" was present in 15%. Patients who bled heavily from one kidney without any apparent cause benefited from orally administered epsilon aminocaproic acid.