Perirenal pancreatic pseudocysts: diagnostic management.

Three cases of pancreatic pseudocysts involving the kidney are presented in which clinical findings or diagnostic imaging favored intrinsic renal disease. Correct diagnosis was established in all cases by sonographically guided cyst aspiration with amylase determinations on the cyst fluid. In addition, laboratory studies ruled out infection, a well known complication of pancreatic pseudocysts. The findings were instrumental in guiding clinical management and insuring correctly timed and properly guided surgical intervention. It is concluded that any patient with a fluid collection in the kidney region may have a pancreatic pseudocyst even without a clear-cut history of pancreatitis or trauma. Fine-needle aspiration is safe and efficacious, and laboratory analysis of cyst fluid should always include amylase determination, in addition to bacteriologic and cytologic evaluation, even if serum amylase is normal.