TNF-α, IL-6, and IL-8 cytokines and their association with TNF-α-308 G/A polymorphism and postoperative sepsis.

Introduction: Early prediction of postoperative sepsis remains an enormous clinical challenge. Association of TNF-α-308 G/A polymorphism with sepsis remains controversial. We, therefore, investigated this polymorphism with serum levels of cytokines TNF-α, IL-6, and IL-8 in relation to development of sepsis following major gastrointestinal surgery.

Methods: Two hundred and thirty-nine patients undergoing major gastrointestinal surgery were enrolled. Polymorphism was studied through the analysis of restriction fragments of Nco1-digested DNA with the polymerase chain reaction. All patients were followed for 1 month following surgery for evidence of sepsis. Levels of serum cytokines TNF-α, IL-6, and IL-8 were measured preoperatively and postoperatively by enzyme-linked immunosorbent assay (ELISA).

Results: Forty-seven (19.66 %) patients developed postoperative sepsis. Patients with postoperative sepsis were significantly (p = 0.002) more likely to possess AA homozygous genotype with higher capacity to produce cytokines TNF-α (p < 0.0001), IL-6 (p < 0.0001), and IL-8 (p < 0.0001) as compared to other genotypes. When compared with patients carrying at least one G allele, the AA genotype was associated with a significantly higher probability (odds ratio (OR) = 4.17; p = 0.003; 95 % confidence interval (CI) = 1.5-11.48) of developing sepsis. Compared with the GG genotype, AA was associated with a significantly higher probability (OR = 5.18; p = 0.0008; 95 % CI = 1.82-14.76) of sepsis development.

Conclusion: TNF-α-308 G/A polymorphism is significantly associated with the development of postoperative sepsis and with increased expression of cytokines TNF-α, IL-6, and IL-8.