OBJECTIVES: To clarify the clinical and pathophysiological characteristics of autoimmune pancreatitis (AIP) in Asia.
METHODS: A retrospective, actual situation survey of AIP diagnosed by Asian criteria was conducted in 10 centers of Japan, Korea, Taiwan, China, and India.
RESULTS: A total of 327 AIP cases (258 male and 69 female subjects; average age, 60.0 years) were enrolled. Obstructive jaundice was the most frequent initial symptom (46%-74%), followed by weight loss (4%-51%) and abdominal pain (19%-44%). Diffuse swelling of the pancreas was frequent in Japan (64%) and Korea (81%), but segmental swelling of the pancreas was more frequent in Taiwan (70%) and China (72%) (P < 0.01). Serum immunoglobulin G4 levels were elevated in 58%-100% of cases in Japan, Korea, and Taiwan. Pathologically, almost all AIPs in Asia were lymphoplasmacytic sclerosing pancreatitis. Sclerosing cholangitis was the most frequent extrapancreatic lesion (60%-81%). Steroid therapy was a major and effective therapeutic strategy in Japan, Korea, and Taiwan. However, the rate of resection or bypass operation was higher in Taiwan (40%) and China (72%) (P < 0.01).
CONCLUSIONS: Features of AIP are fundamentally similar in Japan, Korea, Taiwan, and China. Knowledge of emerging AIP should be more widespread in Asia to avoid unnecessary operation.