#701 Occult hepatitis B infection in kidney transplant recipients and their donors

Abstract

Abstract Background and Aims Occult hepatitis B infection (occult HBV infection—OBI) in kidney transplant recipients (KTRs) poses a potential risk of transforming into an overt process during immunosuppressive therapy. We aimed to evaluate the frequency of OBI occurrence in KTRs population and in the corresponding cohort of kidney donors. Method We analyzed 1222 consecutive KTRs transplanted between Jan 2012 and Jun 2023 and their 670 deceased donors. The diagnosis of seropositive OBI was based on the presence of anti-HBc antibodies without detectable HBs antigen. In eligible KTRs with pre-transplant OBI, the status of HBV infection was examined including the HBV-DNA and calculated aspartate aminotransferase to platelet ratio index (APRI) and Fibrosis-4 (FIB-4) indexes to assess the degree of liver fibrosis. Results Prior to transplantation, OBI was diagnosed in 178 (14.9%) KTRs [median age 49 (IQR, 38-59) years] and in 72 (10.7%) donors [median age 49 (38-58)]. OBI was significantly more frequent in KTRs than in general population (χ2=6.4, p<0.05). In a long-term follow-up period [median 84 (47-117) months], 5 out of 85 pre-transplant OBI patients (5.9%) presented the negative HBc status, whereas HBV viremia and HBs antigen, as determined using the high-sensitive method, were absent in all subjects. Among 85 pre-transplant OBI subjects, anti-HBs antibodies >10 mIU/ml were present in 84.7% and no liver fibrosis was found by APRI and FIB-4 indexes calculation. Conclusion 1. OBI is still a significant clinical problem not only in KTRs, but also in the general population, despite the widespread access to preventive vaccinations against HBV. 2. A separate analysis is necessary to evaluate the influence of OBI on kidney graft and liver function in KTRs.