Maximum FGF21 levels did not correlate with pancreatitis severity; however, the fold increase was greater in severe compared to mild but not moderately severe pancreatitis (4.4 ± 1.0 for mild, 5.5 ± 1.6 for moderately severe, 18.2 ± 11.8 for severe, P = 0.01 mild vs. severe). This evidence concerns the gene FGF21 and pancreatitis.