Asian chronic pancreatitis: the common and the unique

Chronic pancreatitis (CP) is a disabling condition worldwide that presents as pain, maldigestion, and diabetes. It is usually perceived as alcohol related, or classified as idiopathic otherwise. However, this is true only for Western countries. Asian CP comprises not only alcohol-related CP but also tropical pancreatitis (TP). Tropical pancreatitis is a unique entity commonly found in South Asia. It shares similar presentations with other CPs for pain and maldigestion. However, its diabetes is more ketosis resistant. Non-surgical approach like endoscopic therapy plus extracoporeal shock wave lithotripsy provides better outcome for TP than other CPs, because of its less strictured pancreatic duct that is more amenable to endoscopic stone clearance. Diagnosis of CP in Asia mainly relies on image studies such as ultrasonography ± computed tomography (CT) scan, and non-invasive tests on fecal chymotrypsin, serum trypsin, and serum pancreatic isoamylase. Endoscopic ultrasonography and intestinal tubing tests are used mainly in some research centers. Autoimmune pancreatitis (AIP) is another CP originated from Asia in large series and subsequently being recognized in the West. AIP patients seldom present with maldigestion until the disease progresses to a very late stage and this occurs in less than one third of patients. In contrast, AIP is usually presented as pseudotumor of the pancreatic head, causing obstructive jaundice. Immunoglobulin G4 level is typically elevated in AIP and can be used as a marker for responsiveness. Without a need of surgery, steroids are the standard treatment. Those who relapse and are resistant to steroids should be placed on long-term immunosuppressive agents.