Procalcitonin in early allograft dysfunction after orthotopic liver transplantation: a retrospective single centre study

Background Ischemia-reperfusion injury (IRI) is the pathophysiological hallmark of hepatic dysfunction after orthotopic liver transplantation (OLT). Related to IRI, early allograft dysfunction (EAD) after OLT affects short- and long-term outcome. During inflammatory states, the liver seems to be the main source of procalcitonin (PCT), which has been shown to increase independently of bacterial infection. This study investigates the association of PCT, IRI and EAD as well as the predictive value of PCT during the first postoperative week in terms of short- and long-term outcome after OLT. Methods Patients >= 18 years undergoing OLT between January 2016 and April 2020 at the University Hospital of Zurich were eligible for this retrospective study. Patients with incomplete PCT data on postoperative days (POD) 1 + 2 or combined liver-kidney transplantation were excluded. The PCT course during the first postoperative week, its association with EAD, defined by the criteria of Olthoff, and IRI, defined as aminotransferase level > 2000 IU/L within 2 PODs, were analysed. Finally, 90-day as well as 12-month graft and patient survival were assessed. Results Of 234 patients undergoing OLT, 110 patients were included. Overall, EAD and IRI patients had significantly higher median PCT values on POD 2 [31.3 (9.7-53.8) mcg/l vs. 11.1 (5.3-25.0) mcg/l; p < 0.001 and 27.7 (9.7-51.9) mcg/l vs. 11.5 (5.5-25.2) mcg/l; p < 0.001] and impaired 90-day graft survival (79.2% vs. 95.2%; p = 0.01 and 80.4% vs. 93.8%; p = 0.033). IRI patients with PCT < 15 mcg/l on POD 2 had reduced 90-day graft and patient survival (57.9% vs. 93.8%; p = 0.001 and 68.4% vs. 93.8%; p = 0.008) as well as impaired 12-month graft and patient survival (57.9% vs. 96.3%; p = 0.001 and 68.4% vs. 96.3%; p = 0.008), while the outcome of IRI patients with PCT > 15 mcg/l on POD 2 was comparable to that of patients without IRI/EAD. Conclusion Generally, PCT is increased in the early postoperative phase after OLT. Patients with EAD and IRI have a significantly increased PCT maximum on POD 2, and impaired 90-day graft survival. PCT measurement may have potential as an additional outcome predictor in the early phase after OLT, as in our subanalysis of IRI patients, PCT values < 15 mcg/l were associated with impaired outcome.