Optimal imaging conditions for the diagnosis of pleuroperitoneal communication.

A 70-year-old woman with end-stage renal disease caused by a polycystic kidney disease developed massive right-sided pleural effusion 10 days after the initiation of peritoneal dialysis (PD). Although pleuroperitoneal communication (PPC) was suspected, computed tomographic peritoneography on usual breath holding did not show leakage. Therefore, we instructed her to strain with maximal breathing, which caused a jet of contrast material to stream from the peritoneal cavity into the right pleural cavity and allowed the identification of the exact site of the diaphragm defect. Following the thoracoscopic closure of the defect, she was discharged without recurrence of hydrothorax on PD. Hydrothorax due to PPC is a rare complication of PD. Notably, numerous previous modalities used to diagnose PPC lack sufficient sensitivity. Thus, an approach to spread the pressure gradient between the peritoneal cavity and the pleural cavity on imaging may improve this insufficient sensitivity.