Pseudoaneurysm in the abdominal wall as a rare complication following surgery of a chronically superinfected urachal malformation - An exceptional case in congenital malformation surgery.

INTRODUCTION: A pseudoaneurysm, or aneurysma spurium, occurs due to a paravasal hematoma following a vascular injury. Pseudoaneurysms are extremely rare in children and adolescents. Because of the persistent blood flow through the supplying vessel, a potential rupture can cause life-threatening bleeding. Accurate diagnosis and treatment are therefore essential.

PRESENTATION OF CASE: We present the case of an 11-month-old female infant with a congenital, exophytically growing, secreting tumor in the umbilical area. Surgical excision revealed a persistent urachus with a urachal cyst and a malformation on the bladder wall. Postoperatively, severe wound healing disorder developed, along with an intra-abdominal abscess. A pseudoaneurysm in the abdominal wall was incidentally detected with sonography, and CT confirmed perfusion from a branch of the right iliac artery. Initial catheter-based endovascular coiling was unsuccessful, and re-laparotomy for ligation, resection of the pseudoaneurysm, and debridement of the abscess was performed. The further course was complication-free.

DISCUSSION: Pseudoaneurysms, especially post-traumatic ones, can easily be misdiagnosed as a rare differential diagnosis in children and adolescents. Early diagnosis and interdisciplinary treatment are crucial for a successful outcome.

CONCLUSION: In this particular case, it is assumed that the pseudoaneurysm developed as a result of chronic superinfection of the atypical urachal malformation.