SPINK1/PSTI Mutations Are Associated with Tropical Pancreatitis in Bangladesh

Abstract

Background/Aims: Tropical pancreatitis (TP) refers to a severe type of idiopathic chronic pancreatitis that develops in children in tropical regions of Africa and southern Asia. Phenotypically TP is subdivided into fibrocalculous pancreatic diabetes (FCPD) and tropical calcific pancreatitis without diabetes mellitus (TCP). Recently an association was identified between idiopathic pancreatitis in the USA and Europe and mutations in the serine protease inhibitor, Kazal type 1 (SPINK1) gene (previously termed pancreatic secretory trypsin inhibitor, PSTI). Our aim was to determine if either form of TP has a genetic basis. Methods: We studied 8 well-characterized patients from Bangladesh with FCPD, 4 with TCP and 4 controls without pancreatic disease. The entire SPINK1 gene was sequenced in these patients. Results: We detected two disease-associated SPINK1 mutations (N34S/IVS1–37T>C and IVS3 + 2T>C) in 6 of 8 patients from Bangladesh with FCPD but not in 4 patients with TCP (p < 0.03) or 4 controls (p < 0.03). Conclusions: We conclude that SPINK1 mutations are associated with FCPD in Bangladesh. Since SPINK1 mutations in Europeans and North Americans are associated with idiopathic chronic pancreatitis that is phenotypically different from FCPD, we further conclude that mutated SPINK1 markedly increases the risk of developing a variety of pancreatic diseases possibly through a chronic elevation of active trypsin within the pancreas.