Changing of the etiology of acute pancreatitis after using a systematic search

Alcohol and gallstone are the 2 most common etiologies of acute pancreatitis (AP). In Thailand, alcohol has been believed to be the leading etiology of AP. However, a thorough and systematic search may discover real etiology of AP.

During 2006 to 2007, seventy-eight patients with AP were prospectively searched for the etiology by: 1. Performing liver chemistry tests and transabdominal ultrasonography (US) for gallstone in every case; 2. Measuring serum triglyceride and calcium in every case; 3. Investigating definite drugs use or other identified etiology; 4. Asking about the amount of alcohol ingestion (amount > 80 g/day for > 5 years was required for alcoholic AP; 5. Performing CT scan (if age > 40 years) and EUS if no etiology was identified. Results were compared with the retrospective data from medical records of 66 AP patients during 2003-2005.

Of the 78 patients, the etiologies were alcohol in 32 (41%), gallstones in 29 (37%), miscellaneous in 13 (17%) and idiopathic AP in 4 patients (5%). When compared with the retrospective data of the 66 patients over the past 3 years, the etiologies were alcohol 53%, gallstone 22%, miscellaneous 11% and idiopathic 14%. Among the 45 patients of the study period (58%) who consumed alcohol more than the defined threshold for alcoholic AP, 13 (29%) were found to have other explainable causes of AP, i.e gallstones in 10, hypertriglyceridemia in 2 and AIDS cholangiopathy in 1 patient.

Alcohol was probably over-diagnosed as a leading etiology of AP in the past. A systematic search of the etiologies lowered the frequency of alcoholic and idiopathic AP but discovered more patients with gallstone pancreatitis. One-fourth of AP patients who were heavy drinkers had other explainable etiologies of AP.