[The unusual case: a foreign body in the urachus].

INTRODUCTION: In literature cystic tumours and carcinomas of the urachus are commonly described, also the secondary infection of a urachal cyst leading to an abscess is not unusual. But a foreign body penetrating after spontaneous perforation into an existing bland urachal cyst leading to an abscess is extremely rare and not described in literature. Although we made a thorough and extensive literature search we were not able to find a similar case.

CASE REPORT: This report concerns a 38-year-old female patient suffering from diffuse pain in the lower abdomen as well as temperatures up to 39 degrees C referred for further diagnostics and treatment. Further examinations showed an infra-umbilical 6 x 6 cm cystic formation. A CT scan confirmed our suspicion of an inflammatory cystic finding in this area. A subsequent laparoscopic transabdominal excision of this region was -performed. The histological analysis showed a central abscess-forming urachal cyst. Centrally located and causal for the inflammatory process we found a 4-cm fishbone. Even after closer question-ing there was no anamnestic evidence of how this foreign body could have got there. A self-manipulation was resolutely and believably denied by the patient.

CONCLUSION: In our opinion this case is an absolute rarity due to the constellation of two extremely seldom components: a urachal cyst and a probable intestinal perforated foreign body.