The Significance of Interleukin-6 in the Early Detection of Surgical Site Infections after Definitive Operation for Gastrointestinal Fistulae.

BACKGROUND: Surgical site infections (SSIs) are among the most common complications after definitive treatment for intestinal fistulae. Serum inflammatory markers including white blood cell count (WBC), C-reactive protein (CRP), interleukin-6 (IL-6), as well as procalcitonin (PCT) have been used to help diagnosis post-operative complications.

OBJECTIVE: The goal of this study was to assess the clinical value of inflammatory markers, specifically IL-6, in predicting SSIs after intestinal fistulae resection.

METHODS: A total of 184 consecutive patients who underwent elective intestinal fistula resection were enrolled prospectively. All patients were screened to exclude patients with existing clinical infection. Plasma IL-6 concentrations, serum PCT, and CRP concentrations were measured pre-operatively and on post-operative days one, three, and seven. The predictive value of each laboratory marker for SSI was calculated.

RESULTS: The incidence of SSI after elective intestinal fistula resection was 26.7%. Interleukin-6, PCT, and CRP concentrations were higher in patients with SSIs compared with patients without. In contrast, there was no statistical difference for WBC counts between the two groups. Receiver operating characteristic curves demonstrated that IL-6 had the highest diagnostic effectiveness for post-operative SSI on post-operative day one, with an area under the curve of 0.77, and a sensitivity of 85.7% and specificity of 63.9%.

CONCLUSION: A concentration of IL-6 above 95.6 ng/L on post-operative day one and 52.5 ng/L on post-operative day three, and a concentration of PCT exceeding 0.61 mcg/L predict the occurrence of SSI after definitive operations for gastrointestinal fistulae.