Long-term follow-up of patients with asymptomatic hematuria

Of 608 patients with a diagnois of either gross or microscopic hematuria at their first visit, 280 were found to display abnormalities that could indicate the etiology of the hematuria through examinations, Urologic diseases represented the most frequent etiology (70.5%). Of the 328 patients of unknown etiology, 104 were subjected to long-term follow-up studies. These patients were assessed at an average interval of 37.7 months after their first visit. All patients were living and doing well at the time of questionnaire. Causative diseases were not determined in all but one case. Drug-induced discoloration of the urine was the final diagnosis in this one patient.