The causes of acute pancreatitis in Finland are alcohol overuse (60%), cholecystolithiasis (20%) and idiopathic (i.e. etiology unknown)(20%). Acute pancreatitis may recur in over half of cases and may be fatal in severe cases in 30%. Majority of idiopathic pancreatitis are caused by microlithiasis in gall bladder. The purpose of this randomized study is to prevent recurrence of idiopathic pancreatitis by performing laparoscopic cholecystectomy compared to non-operative group in 2 years follow-up of patients.