Reflux Pancreatitis: Expect the Unexpected in Urinary Retention

Abstract

Introduction: Pancreatic transplant is a newer modality for treatment of insulin dependent diabetes mellitus (DM). When diabetic nephropathy progresses to end stage renal disease (ESRD), combined pancreas and kidney transplant improves post-transplant survival and outcomes. Patients can often develop unusual complications due to post surgical anatomical changes. We present an unusual case of transplanted pancreatic graft pancreatitis secondary to urinary retention. Case: A 44 year old male with past medical history of type 1 DM, ESRD on HD due to diabetic nephropathy s/p simultaneous kidney and pancreas transplant in 2010 on maintenance immunosuppression therapy, now with CKD II presented with fever, RLQ abdominal pain and urinary complaints of hesitancy, frequency, straining and incomplete evacuation. He denied any nausea, vomiting, changes in bowel movement or abdominal distention. His transplant pancreas has exocrine excretion in urine with no evidence of graft rejection. Lab studies revealed elevated serum lipase, amylase and acute kidney injury. Initial abdominal ultrasound revealed mild hydronephrosis of the transplanted kidney, high post-void residual volume and enlarged prostate. Abdominal CT scan showed pancreatic transplant in the RLQ with peripancreatic fluid and stranding consistent with graft pancreatitis. His urinary amylase was elevated (>7500U/L). He was treated with urinary catheterization to relieve retention, hydration and urology evaluation for management of prostate hypertrophy. Discussion: Graft pancreatitis from urinary reflux is one of the complications of pancreas transplant with urinary exocrine drainage. Chemical cystitis and urethritis, recurrent hematuria and bladder stones are common because alkaline pancreatic enzymes are a source of irritation to the urogenital epithelium. The advantage of exocrine bladder drainage is the ability to use urine amylase to monitor for rejection after pancreatic transplant. Enteric exocrine drainage is superior in terms of complications but survival remains the same in both. A urologic condition like prostatic hypertrophy should be managed promptly due to potential risk of rejection of both kidney and pancreatic grafts.