Unexpected anterior urethral diverticula.

Most anterior urethral diverticula present in infancy with urinary obstruction or retention. When they present after infancy they do so with recurrent urinary tract infections or dribbling of urine. Three boys with late-presenting diverticula are described. Unless good oblique radiographs are specifically taken, with a fast flow, then the diagnostic arcuate filling defect of the proximal lip of the diverticulum can be missed. There may be few signs of obstruction. With diagnostic radiographs the urologist must be urged to repeat a negative cystoscopy. Diverticula must be differentiated from strictures or acquired diverticula following trauma.