Delayed Presentation of Urinoma Following Renal Transplant Biopsy: A Case Report.

A urinoma is an unusual complication following renal transplant biopsy that can easily be missed or mistaken for a hematoma. In addition to trauma to the renal collecting system, a degree of urinary tract obstruction is required for urine to leak into the surrounding tissues and form a urinoma, which can in turn cause pressure on surrounding structures. This case report describes a patient who developed ipsilateral leg swelling several months after a renal transplant biopsy. Imaging demonstrated a perirenal transplant fluid collection, which biochemical analysis confirmed to be urine. This was successfully managed with percutaneous nephrostomy and antegrade ureteric stent insertion. The fluid collection persisted as a seroma however, and the patient proceeded to have peritoneal fenestration and marsupialization surgery. To our knowledge, this is the first reported case of urinoma complicating a renal transplant biopsy. This case highlights a diagnosis that can be easily missed and is therefore a potential pitfall for clinicians.