Soluble triggering receptor expressed on myeloid cells-1 as a marker for early detection of infection in postoperative patients

Abstract

Background Triggering receptor expressed on myeloid cells-1 (TREM-1) is recently identified to be involved in infectious inflammatory responses, and is expressed on the surface of immune cells. TREM-1 acts in synergy with toll-like receptor signaling pathways in amplifying the inflammatory response mediated by several microbial components. TREM-1 is not upregulated with noninfectious inflammatory disorders. Besides its membranous form, a soluble counterpart of TREM-1 (sTREM-1) exists that is released with several infectious processes. Objective Our study aimed to investigate the diagnostic and prognostic value of plasma sTREM-1 levels in postoperative patients with sepsis. Patients and methods Samples were collected from 50 postoperative patients presented with systemic inflammatory response syndrome (SIRS) and a suspected infection to estimate plasma sTREM-1 level within the first 12 h, day 3, and day 7 postoperatively, together with C-reactive protein and lactate. Patients were classified according to absence or presence of infection into SIRS and sepsis groups; the sepsis group was further subdivided according to absence or presence of organ dysfunction into sepsis and septic shock subgroups. Results With high significant difference, sTERM-1 was capable of distinguishing SIRS from sepsis, and also between sepsis and septic shock subgroups, with sensitivity, specificity, and predictive values comparable with other candidate indicators on day 1, day 3, and day 7 (P The best cutoff value of sTREM-1 for differentiating SIRS from sepsis was 95 pg/ml, which yielded a sensitivity of 97.2%, specificity 92.8%, positive predictive value 97.2%, negative predictive value 92.9%, and area under the curve of 0.983, whereas the best cutoff value of sTREM-1 for prediction of death in postoperative patients with sepsis was 400 pg/ml, which yielded a sensitivity of 97.6%, specificity 87.5%, positive predictive value 97.6%, negative predictive value 87.5%, and area under the curve AUC of 0.955,. Conclusion We conclude that sTREM-1 could act as an early detector of infection in postoperative patients and also as a predictor for mortality by an accuracy superior to other sepsis parameters.