Serine Protease Inhibitor Kazal type 1 (SPINK1) protects against premature intracellular activation of trypsinogen and development of acute pancreatitis. Our aim was to determine the prevalence of SPINK1 mutations (a) in unselected patients with first-time acute pancreatitis and (b) in the Danish background population (c) in a meta-analysis to combine the results with findings in similar investigations worldwide and (d) to evaluate whether patients with SPINK1 mutations had a more severe clinical course.