Postoperative Interleukin-6 Predicts Intra-abdominal Septic Complications at an Early Stage After Elective Intestinal Operation for Crohn's Disease Patients

Abstract

Background: The role of interleukin-6 (IL-6) in the prediction of intra-abdominal septic complications (IASCs) in patients with Crohn's disease (CD) remains unclear. We assessed the serum IL-6 time course and its association with postoperative IASCs in patients undergoing elective intestinal operations for CD.

Methods: In total, 118 patients who underwent intestinal operations for CD were prospectively evaluated. They were divided into an IASC group and non-IASC group. Multivariate analyses were used to identify risk factors, and receiver operating characteristic curve analysis was performed.

Results: Multivariate analysis showed that a high IL-6 concentration of >137.25 pg/mL on postoperative day (POD) 1 was independently associated with IASCs (odds ratio, 5.74; 95% confidence interval [CI], 1.46-22.67; P = 0.012) and a longer postoperative length of hospitalization (6 vs 9 days, P < 0.001). The median interval between surgery and IASCs (interquartile range) was 6 (4-22) days, and the IL-6 concentration was significantly different between patients with and without IASCs on PODs 1, 3, and 5. The ideal IL-6 cutoff value on POD 1 for the prediction of postoperative IASCs was 137.25 pg/mL, yielding a sensitivity of 81%, specificity of 58%, and area under the curve of 0.71 (95% CI, 0.59-0.83), with a negative predictive value of 0.93.

Conclusions: A high IL-6 concentration on POD 1 is independently associated with the occurrence of postoperative IASCs in patients undergoing elective surgery for CD and could allow for earlier diagnosis and earlier intervention for IASCs compared with C-reactive protein.

Keywords: Crohn’s disease; interleukin-6; intestinal operation; intra-abdominal septic complications; postoperative.