D-dimer Level Is Non-Specifically Elevated Post-Living-Related Liver Transplantation in Children

Background/Objective: D-dimer, a soluble fibrin degradation product, is used to be a marker of vascular thrombosis. However, it has been reported to be elevated in different pathological conditions other than thrombosis. Moreover, its pattern post-liver transplantation (LT) in children is not known. So, we aimed to report its pattern within the first-month post-LT in children and its level in different early post-LT complications. Methods: It is a retrospective observational cohort study in which 52 children who underwent living-related liver transplantation (LRLT) were included. All the available clinical, imaging, and laboratory data including D-dimer level were collected from the patients' files. Those who developed complications within the first post-LT month were assigned to the complication group (n=41), and others were assigned to the non-complication group (n=11). Results: D-dimer level pre-LT ranged from 0.12-16.41 mg/l, with no significant difference between the complication and non-complication groups. Postoperatively, the D-dimer levels were elevated and did not normalize till the postoperative day (POD) 30. The minimum reported level was 1.2 mg/l on POD0 while the maximum one was 33.12 mg/l on POD12. There were no significant differences between the complication and non-complication groups about the D-dimer level from the pre-LT day till the POD30 (p>0.05). The D-dimer level at the onset of the different complications showed no significant difference among the thrombotic, ACR, and the other complication subgroups (p=0.748). Moreover, the vascular thrombosis subgroup didn’t show a significant difference between the D-dimer level before- and at the onset of thrombosis (p=0.480). Conclusion: D-dimer is non-specifically elevated within the 1^st-month post-LRLT in children with no clear trend. Moreover, it doesn’t normalize till the end of the 1^st post-LT month. Being high early postoperatively doesn't necessarily indicate vascular thrombosis or other complications but rather the nature of the transplantation circumstances.