Importance of occult haematuria found at screening.

A retrospective study of the results of dipstick testing and microscopical examination of urine from 10 050 men undergoing health screening showed a prevalence of occult haematuria of 2.5%. Those patients with occult haematuria who were resident in the United Kingdom and registered with a general practitioner were identified and a questionnaire sent to their general practitioners asking what further investigations had been performed. The response rate was 92% (152/165 inquiries). Fifty nine general practitioners (39%) had not instigated any investigations. Among the 76 patients who underwent some further investigations abnormalities were found in 21 (28%); and among those fully investigated by examination of midstream urine, intravenous urography, and cystoscopy abnormalities were found in 12(50%). These included bladder neoplasms (two; one in a patient aged 37), epithelial dysplasia (one), staghorn calculi (one), and chronic reflux nephropathy (one). It is proposed that occult haematuria should be fully investigated regardless of the age of the patient.