Pancreatitis severity was compared between caerulein-induced pancreatitis and caerulein-induced pancreatitis after repetitive microlithiasis ejection.<h4>Results</h4>Significantly higher infiltration of CD45-positive leukocytes and increased NLRP3 expression were observed in papillary biopsies from patients with microlithiasis-induced acute pancreatitis compared with patients with alcohol-induced acute pancreatitis and control subjects. This evidence concerns the gene PTPRC and alcohol drinking.