Serum Interleukin 17 as An Early Prognostic Biomarker of Severe Acute Pancreatitis Receiving Continuous Blood Purification

Abstract

Background

Severe acute pancreatitis (SAP) is associated with systemic inflammation, immunoparalysis, and sepsis, and may lead to vital organ failure and death. We evaluated the efficacy of serum interleukin 17 (IL-17) concentration for predicting eventual SAP severity and the clinical benefits of removing IL-17 by continuous veno-venous hemofiltration (CVVH).

Methods

Patients were divided into 2 groups according to severity: Grade 1 (n = 18, SAP without organ dysfunction) and Grade 2 (n = 18, SAP with organ dysfunction). 20 healthy volunteers served as controls. All patients underwent 24-h CVVH and blood samples were taken at 0, 6, 12, and 24 h for measurement of bacterial load and serum IL-17, IL-6, and endotoxin. Clinical condition was graded by the sequential organ failure assessment (SOFA) score.

Results

Baseline IL-17, IL-6, endotoxin, and bacterial load were higher in Grade 2 patients. SOFA scores improved significantly, and serum IL-17, IL-6, endotoxin, and bacterial load decreased significantly in all patients after CVVH. Serum IL-17 was significantly and positively correlated with IL-6, bacterial load, and endotoxin during CVVH treatment. In addition, post-CVVH serum IL-17 was directly correlated with SOFA scores on days 1 and 7, and with duration of hospital stay. Non-survivors showed both higher SOFA scores on day 1 and higher baseline IL-17 than survivors.

Conclusions

Earlier and higher serum IL-17 elevation predicted prolonged hospitalization, organ failure, and death, possibly by disrupting gut barrier function. CVVH can remove inflammatory cytokines from serum, including IL-17 and IL-6, thereby attenuating the inflammatory response and diminishing associated systemic complications.