Diffuse Type Autoimmune Pancreatitis: The First Case Report in Thailand
Varayu Prachayakul MD*, Pitulak Aswakul MD*, Piyaporn Apisarnthanarak MD**, Supot Pongprasobchai MD*
Affiliation : * Division of Gastroenterology, Department of Internal Medicine, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand ** Department of Radiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand
Background : Autoimmune pancreatitis (AIP) is a recently-recognized form of pancreatitis mimicking pancreatic cancer
(PaC) but treatable with corticosteroid. There is one report of focal-type AIP in Thailand. Here we presented the first case
report of diffuse-type AIP.
Case Report : A 76-year-old man presented with 10-day obstructive jaundice. Computed tomography (CT) showed obstructive
jaundice from diffusely swollen pancreas, which had a characteristic capsule-like rim non-enhancement pattern of AIP. Serum
immunoglobulin G4 (IgG4) was elevated of 468 mg/dL. Endoscopic ultrasound-guided fine needle aspiration demonstrated
no PaC. Prednisolone 40 mg/day was started. Jaundice disappeared in 2 weeks and follow-up CT demonstrated normalization
of swollen pancreas.
Conclusion : Diffuse-type AIP does exist in Thailand. Recognition of this condition is critical to avoid misdiagnosis of PaC or
unnecessary surgery.
Keywords : Autoimmune pancreatitis, Diffuse type, IgG4
