Toll-like receptor polymorphisms (TLR2 and TLR4) association with the risk of infectious complications in cardiac surgery patients

Background. Postoperative infection is a common healthcare-associated problem, and unfortunately, a serious complication in cardiac surgery patients. Toll-like receptors (TLRs) are crucial in activating non-specific immunity mechanisms and integrating elements of the immune system, due to interactions between specific and non-specific responses. Objectives. In this study, the association of TLR2 or TLR4 with the risk of postoperative infections in cardiac surgery patients undergoing a coronary artery bypass grafting (CABG) procedures was investigated. Materials and methods. Our research was carried out on a cohort of 299 consecutive adult patients with ischemic heart disease (IHD) who underwent a planned CABG procedure. These patients were monitored for the presence of a postoperative infection over a 30-day observation period. All patients were investi-gated for 2 TLR2 gene mutations - R753Q (rs5743708) and T16934A (rs4696482), and 2 polymorphisms of the TLR4 gene - D299G (rs4986790) and T399I (rs4986791). The final stage of the study was an evalu-ation of the hypothetical association between TLR2 and TLR4 gene variances and postoperative infections in patients undergoing CAGB procedures. Results. The prevalence of infections in the final cohort was 15.3% (46/299). The most common infections were surgical site infections, which were diagnosed in 21 patients (45.6%), bloodstream infections in 15 pa-tients (32.6%) and pneumonia in 10 patients (21.8%). Logistic regression demonstrated that the presence of the AG+GG of D299G (rs4986790) and CT+TT of T399I (rs4986791) variants was related to a higher incidence of infection in patients undergoing CAGB procedures. Conclusions. To our knowledge, this is the first study of its kind to demonstrate that TLR2 and TLR4 muta-tions affect the risk of post-CABG infections. Being a carrier of the AG+GG of D299G (rs4986790) or CT+TT of T399I (rs4986791), TLR4 variants constitute a postoperative risk factor for infection in patients undergoing CAGB procedures.