Variations of serum IL-33 and sST2 levels in patients with acute pancreatitis and its clinical significance

Objective To study changes and clinical significance of serum interleukin- 33( IL- 33) and its soluble receptor s ST2 levels in patients with mild or severe acute pancreatitis( AP). Methods Totally,36 AP patients were selected and divided into mild acute pancreatitis group( MAP,n = 16) and severe acute pancreatitis group( SAP,n = 20). Fasting venous blood samples were drawn on the day of admission and were repeated at 3,7 and 14 days later. Venous blood samples from 18 healthy volunteers were drawn one time as controls. Serum IL- 33 and s ST2 levels were measured by enzymelinked immunosorbent assays and were correlated with the severity of acute pancreatitis. Results( 1) Serum IL- 33 level in the SAP group was significantly higher than that in the control group on the 1st day( P 0. 05). Serum s ST2 levels in the MAP and SAP groups were both significantly lower than that of the control group on the 1st day( P 0. 01).( 2) Compared to those in the MAP group,serum IL- 33 levels in the SAP group were significantly increased on the 1st,3rd,7th and14 th day after admission( P 0. 01).( 3) Serum IL- 33 level in the AP patients showed a positive correlation with Serum s ST2 level on the 3rd day( r = 0. 337,P 0. 05) and on the 1st and the 3rd day in the SAP group( SAP 1d: r = 0. 490,P 0. 05; SAP 3d: r = 0. 574,P 0. 01).( 4) Serum IL- 33 level in the AP patients showed a good positive correlation with Ranson's 11 criteria on the 1st day( r = 0. 436,P 0. 01). Conclusion IL- 33 may have proinflammatory effects in the early phase of SAP and its serum level reflects the severity and prognosis of SAP. s ST2 is a participant of early- phase reaction and in AP and plays a protection role. These two cytokines interact and regulate each other during AP.