Pancreatic pseudocyst with spontaneous cutaneous fistulization: Case report

RATIONALE: Pancreatic fistula occurs as a result of pancreatic duct disruption during acute pancreatitis. An external or pancreatico-cutaneous fistula is defined as a leakage of pancreatic secretion through an abdominal wound or previously inserted drain. If the extravasated pancreatic juice is walled-off by the fibrous or granulation tissue, a pseudocyst is formed. Fistulization of the pancreatic pseudocyst into the different surrounding hollow viscera is reported. However, we present a patient with spontaneous cutaneous fistulization of the pancreatic pseudocyst into the lumbar region successfully treated conservatively. Such an extremely rare presentation is only reported twice and thus highly unexpected during the follow-up of patients after recovery from acute pancreatitis. PATIENT CONCERNS: The patient presented with 5-days intermittent fever and a tender, fluctuant, and erythematous swelling of the left lumbar paravertebral region with black necrotic skin spot on the top of it. DIAGNOSES: Abdominal computed tomography scan revealed retroperitoneal pseudocyst originating from the pancreatic body and tail and extending to the left flank. INTERVENTIONS: Incision of the swelling evacuated dark amylase rich fluid. Colostomy disc and bag were applied to collect further spontaneous outflow of pseudocyst content. OUTCOMES: Symptoms instantly resolved and the patient was managed conservatively with ambulatory follow-up of the daily volume of fistula discharge. Over the next 37 days daily fistula output gradually reduced to nil with the spontaneous closure of the external skin fistula opening. LESSONS: Frequent follow-ups of patients after severe acute pancreatitis are necessary for early detection and timely successful treatment of pancreatic pseudocysts with such unusual and rare presentation.