Prolonged postoperative urine leakage due to a calyceal diverticulum mimicking a renal cyst: A case report and literature review

BACKGROUND: The calyceal diverticulum is a rare cystic cavity that communicates with the collecting system via a narrow neck or infundibulum. In clinical practice, part of the calyceal diverticula is difficult to differentiate from simple renal cysts even after contrast-enhanced CT. To date, there have been few kinds of literature works on the diagnosis and treatment of calyceal diverticulum combined with renal pelvis dilatation, especially concerning the treatment of prolonged postoperative urine leakage. CASE DESCRIPTION: A 53-year-old woman with calyceal diverticulum and renal pelvis dilatation mimicking a simple renal cyst suffered urine leakage after receiving laparoscopic unroofing of the renal cyst. A persistent urine leakage was observed immediately after surgery, with about 200 ml of drainage fluid per day. We first attempted to place a double-J ureteral stent and indwell a catheter. After failing that, conservative treatment was performed. The core idea of the conservative treatment is retaining the drainage tube for more than 1 month, then clamping the drainage tube for 1 week, and finally removing the drainage tube. By 3 weeks of follow-up, the urine leakage disappeared, and the CT scan showed hydronephrosis of the right kidney without perirenal exudation and the lower pole cyst of the right kidney shrank significantly. CONCLUSION: This case, we reported here, is to attract the attention of clinicians. Renal cysts should exclude the possibility of the calyceal diverticulum. If urine leakage is inevitable after surgical treatment, our conservative treatment strategy is also an alternative method.