Renal subcapsular fluid collection caused by penetration of a pancreatic pseudocyst.

A 63-year-old man presented with left flank pain and spiked fever. Computed tomography revealed a pancreatic cyst and left renal subcapsular fluid collection that appeared to be connected to the cyst. High levels of amylase and lipase were observed in a test puncture of renal fluid collection. The cause of the fluid collection was diagnosed as penetration of the pancreatic pseudocyst. Endoscopic nasobiliary drainage was used to drain the pancreatic pseudocyst and renal subcapsular fluid collection. The present case demonstrated that renal subcapsular fluid collection may be caused by penetration of a pancreatic pseudocyst.