Congenital giant diverticulum of the posterior urethra in a 4-year-old boy.

A congenital giant diverticulum of the posterior urethra in a 4-year-old boy is reported. The theories on development of congenital urethral diverticula are considered and the importance of the clinical, radiological, endoscopical and histological examination for the differential diagnosis of the acquired diverticula and enlarged utricle is emphasised. In the majority of diverticula transurethral unroofing is most appropriate. The larger and symptomatic diverticula require open excision and eventually urethral reconstruction. Small asymptomatic diverticula may not require any treatment.