The changes in the levels of fatty acid binding proteins in donors and recipients in living donor liver transplantation: Prospective case control study evaluating markers of ischemia and reperfusion injury

Aim: The aim of the present study is to evaluate the levels of A-FABP, I-FABP, and L-FABP in donors and recipients of living donor liver transplantation (LDLT) in order to elucidate possible biomarkers for ischemia/reperfusion injury and related complications such as graft dysfunction, postoperative early complications leading to re-laparotomy and mortality. Materials and Methods: Fifty-five recipients who underwent LDLT and 33 donors who received living donor hepatectomy were included for analysis to this prospective case control study from a cohort of 307 patients (recipients [n=158] and donors [n=149]) who were operated between June 2020 and February 2021 in Inonu University Liver Transplant Institute. 46 of the recipients had Clavien-Dindo grade 3 and 4 complications and 9 had normal postoperative course. The donors had uneventful postoperative course. The demographic, clinical, laboratory and operative characteristics of the patients were prospectively recorded. Specific laboratory parameters including A-FABP, I-FABP, L-FABP, IL-6 and MDA were analyzed using enzyme linked immunosorbent assay (ELISA) in our institute's hepatology research laboratories. The routine laboratory work-up and serum samples for the specific laboratory parameters were collected in the preoperative, postoperative 1st, 8th and 30th days. Results: The serum I-FABP, A-FABP, L-FAP, and IL-6 did not show significant difference between the donors and recipients at designated time periods (p>0.05). However, MDA was significantly higher in the recipients in all designated time periods (p<0.05). The evaluation of the course of I-FABP, A-FABP, L-FAP, MDA and IL-6 in the designated time periods showed that the changes in the levels of these parameters at the designated time points were significant (all, p<0.05). Specific laboratory parameters did not show significant change at designated time period in the recipients (all, p>0.05). Preoperative A-FABP, L-FABP was significantly higher in recipients with complications (p<0.05). Preoperative I-FABP, A-FABP, and L-FAP was significantly higher in recipients who required re-laparotomy (p<0.05). Conclusions: Preoperative FABP, A-FABP, and L-FABP levels were significantly higher in patients with complicatons. They may be a useful toll for prediction of complications. They are higher than any other laboratory parameter and do not depend on the demographic, clinical an operative data of the patients. Further studies are required for evaluation of the efficacy of these new biomarkers. Key Words: Ischemia and reperfusion injury, liver transplantation, fatty acid binding proteins