Open Pyelolithotomy in the Presence of a Retro-Renal Colon: A Safe Alternative in Resource-Limited Settings.

A retro-renal colon (RRC) is a rare but important anatomical variant to consider when planning percutaneous stone surgery. CT scanning of the abdomen is critical to detect this and to plan the surgical approach to avoid injury to the colon. In this case report, a 38-year-old woman with large obstructing bilateral symptomatic renal stones was found to have a left retro-renal colon on image review prior to left percutaneous nephrolithotomy. An open pyelolithotomy was performed to surgically remove the stone and to prevent any injury to the colon. An RRC can occur in up to 16% of patients undergoing percutaneous renal access. A CT scan is important to rule out this anatomical variant and to allow for surgical planning to avoid injury to the colon. The modern era of endourology has brought a significant reduction in open stone surgery. An open pyelolithotomy is still a safe option for stone removal if an RRC is detected preoperatively. Injury to the colon during percutaneous access can most commonly be managed conservatively. Occasionally open intervention may be required. An RRC detected on a preoperative CT scan may influence surgical planning and an open pyelolithotomy can be performed to safely remove renal stones and prevent colonic injury, especially in resource-limited settings.