A 19-year-old woman with chronic kidney disease (stage 5D, secondary to C3 glomerulopathy), under peritoneal dialysis since May 2019, presented with retrosternal pain and dyspnea during a Nephrology appointment. Chest radiography revealed right pleural effusion of moderate/ large volume.

The patient had been recently submitted to thoracocentesis.

The pleural fluid was a transudate with a glucose concentration of 200 mg/dL, which raised the suspicion of pleuroperitoneal communication. To confirm the diagnosis a peritoneal scintigraphy was requested.

An intraperitoneal injection of 185 MBq of (99mTc) Tc-macroaggregated albumin was performed via the Tenckhoff catheter, along with the instillation of dialytic solution (2.3% glucose). Thoracic and abdominal static images were acquired 5 hours after the administration of the radiopharmaceutical in anterior (A), posterior (B) and lateral right (C) and left (D) views. In our department there are no SPECT-CT facilities, so a (99mTc) Tc-pertechnetate mark was placed at xiphoid process to help anatomy location (black arrow)(Fig. 1).

Peritoneal scintigraphy demonstrated leakage of peritoneal fluid into the right pleural cavity, with no abnormal tracer accumulation detected in the left hemithorax, thereby confirming a right pleuroperitoneal communication. The patient was transferred to hemodialysis. ^1,2,3,4