A case of acute obstructive suppurative pancreatic ductitis complicated with acute cholangitis diagnosed only after the removal of a pancreatic duct stent.

Acute obstructive suppurative pancreatic ductitis (AOSPD) is a rare complication of chronic pancreatitis that presents with high fever and abdominal pain. A 63-year-old man underwent plastic bile duct stent and plastic pancreatic duct stent (PDS) placement for benign stricture in the intrapancreatic bile and pancreatic ducts associated with chronic pancreatitis; the stents were routinely replaced. Seven months after the last replacement, the patient presented to our hospital with dark urine but without fever or abdominal pain. Subsequent blood tests revealed elevated levels of hepatobiliary enzymes, white blood cells, and C-reactive protein. However, the pancreatic enzyme levels remained unchanged, and abdominal computed tomography showed the absence of inflammation around the pancreas. He was initially diagnosed with acute cholangitis (AC) due to bile duct stent dysfunction and subsequently underwent emergency endoscopic retrograde cholangiopancreatography. As obstruction of the PDS was suspected, both bile duct stent and PDS were replaced. Although the collected bile did not exhibit purulence, a white purulent fluid was released after replacing the PDS. Cultures from the bile and pancreatic exudates revealed the presence of . Consequently, the patient was diagnosed with AOSPD and AC. In this patient, endoscopic retrograde cholangiopancreatography was performed after the diagnosis of AC alone; however, relying solely on AC treatment might not have ameliorated the patient's condition. The patient did not complain of any abdominal pain and was diagnosed with AOSPD only after the replacement of his PDS. Our case suggests that AOSPD may be a pitfall in the identification of the source of inflammation in patients with chronic pancreatitis.