[Urachal sinus presenting as umbilical drainage in an adult male]

Although urachal remnants are very rare, dermatologists must be aware of them in order to ensure suitable treatment by urologists. Lack of appropriate treatment exposes patients to the risks of recurrent infectious complications or degeneration to vesical adenocarcinoma.

A 32-year-old man consulted for mild and recurring umbilical weeping for approximately 1 year. He had previously undergone unsuccessful treatment, comprising application of liquid nitrogen and of silver nitrate to an umbilical lesion measuring several millimetres regarded as pyogenic granuloma. The diagnosis of urachal sinus was suspected clinically (umbilical weeping or inflammation) and confirmed by urological scan.

A defect involving partial or total obliteration of the urachal canal after the fifth month of gestation can result in four types of benign abnormalities. Patent urachus (50%) is diagnosed during the neonatal period, while in adults, the most frequent form is a urachal cyst (30%), with sinuses (15%) and the diverticula (5%) being very rare. The urachus and its implantation base on the bladder must be removed surgically. Laparoscopic surgery offers a valuable alternative to open-surgery and probably leads to less morbidity and shorter convalescence in active young subjects.