Successful Identification and Closure of an Occult Pleuroperitoneal Communication Using Intraoperative Indocyanine Green Fluorescence in a Patient Undergoing Peritoneal Dialysis: A Case Report.

Pleuroperitoneal communication (PPC) is a rare complication of peritoneal dialysis that often necessitates discontinuation due to recurrent pleural effusion. In some cases, the diaphragmatic defect is not visible under standard thoracoscopic inspection, making intraoperative localization challenging. Indocyanine green (ICG) fluorescence has emerged as a useful method for detecting occult fistulas. We report the case of a 51-year-old man undergoing peritoneal dialysis for end-stage renal disease who developed right pleural effusion and poor dialysate outflow three months after initiation. Radionuclide peritoneal scintigraphy demonstrated tracer accumulation in the right hemithorax, confirming PPC. Thoracoscopic inspection revealed no visible diaphragmatic defects. Following intraperitoneal injection of 1,500 mL of dialysate mixed with 25 mg of ICG, near-infrared imaging identified two focal fluorescence points on the diaphragmatic dome. These sites were closed using pledget-reinforced horizontal mattress sutures and covered with a polyglycolic acid sheet and fibrin glue. Peritoneal dialysis was successfully resumed on postoperative day seven, and the patient has remained free of recurrent effusion for two years. ICG fluorescence imaging enables rapid and minimally invasive identification of subtle diaphragmatic fistulas that may not be detectable under standard thoracoscopy. This technique may improve intraoperative localization and increase the success of surgical repair in PPC.