Hepatitis B infection reactivation profilacy results in patients receiving immunesupressive treatment and comparison of entecavir and tenofovir

Hepatitis B virus (HBV) is a double stranded DNA virus which belongs to the hepadnavirus family with antigenic structures such as Hepatitis B surface antigen (HBsAg), Hepatitis B e antigen (HBeAg) and Hepatitis B core antigen (HBcAg). Clinical forms such as acute hepatitis, fulminant hepatitis, chronic hepatitis, liver cirrhosis and hepatocellular carcinoma (HCC), developing in consequence of this virus are among the disease proups that have an important place among the health problems of our country (1). The contamination comes true with parenteral, vertical, sexual and horizontal ways fundamentally. The virus is not cytopathic by itself and causes cellular damage by activation of the immune system (3). The vaccine has been present since 1981, and was placed in the routine vaccination program in our country in 1997. Various vaccines and antiviral drugs have been developed to prevent and treat HBV related infection. The main purpose of antiviral drugs is HBsAg loss. However, absolute success is not possible until the 'covalently closed circular DNA' (cccDNA) is completely cleared from the hepatocyte nucleus. Unfortunately, there is currently no cure that provides cccDNA loss. Patients who have a history of contact with HBV, develop natural immunity, or have HBsAg positive and no indication for antiviral therapy are at risk for HBV reactivation and acute exacerbation when receiving immunosuppressive therapy. In this study, we aimed to present the efficacy of preemptive antiviral therapy and the data of patients who developed reactivation in patients living in Tokat region, who were initiated by various clinics at Gaziosmanpaşa University Hospital and who were referred to the Gastroenterology outpatient clinic for the necessity of antiviral treatment. Patients who applied to the Gastroenterology outpatient clinic between 2016 and 2018 were retrospectively screened. 177 of 425 patients who were referred for evaluation of preemptive antiviral treatment were included in the study. The patients were divided into risk groups according to their serological status and immunosuppressive treatments. Demographic features, relevant liver tests, preemptive treatment type, duration of treatment, transaminase levels and HBV serology and clinical conditions were recorded. Patients who developed in our study during reactivation in our study during their follow-up according to the reactivation criteria were additionally examined. Of the 177 patients included in the study, 94 (53.1%) were male and 83 (46.9%) were female. 99 (55.94%) patients were in the low-risk group, 76 (42.94%) patients were in the medium-risk group, and 2 (1.12%) patients were in the high-risk group. The number of patients with hepatosteatosis on ultrasonography was 47 (26.6%). The mean age was 61.12 ± 10.99 years. The youngest age was 27, the oldest was 84. The mean antiviral treatment duration was 19.73 months. The number of patients using Entecavir was 115 (65.0%), and the number of patients using Tenofovir Disoproxil Fumarate was 59 (33.3%). Apart from these patients, 1 patient was switched from Tenofovir Disoproxil Fumarat to Entecavir due to side effects. 1 patient was switched from Lamivudine to Entecavir due to drug resistance. Initially, one patient using Lamivudine switched to Entecavir for drug resistance and then to Tenofovir Disoproxil Fumarate for reactivation. When the patients who developed reactivation were evaluated, their average age was 54.82 / year. The average age of patients who did not develop reactivation was 61.54 / year. The mean age of patients who developed reactivation was statistically significantly lower than who did not develop reactivation (p=0.049). Three (27.3%) of the patients who developed reactivation were male and 8 (72.7%) were female. There was no difference between the sexes in terms of reactivation (p=0.66). According to the measurement results made at the beginning of treatment, while 8 (36.36%) of 22 HBsAg positive patients developed reactivation, 3 (155%) of 155 HBsAg negative patients developed reactivation. HBsAg positivity was determined as a risk factor for reactivation (p<0.001). The patients were divided into two groups according to the immunosuppressive treatment they received. here was no significant difference in reactivation development between both groups (p=0.735). When evaluated according to risk groups, it was found that patients who developed reactivation in the medium risk group were significantly higher than other groups (p=0.003). When evaluated in terms of preemptive antiviral treatments, there was no significant difference in reactivation (p=0.2). When evaluated according to anti-HBs serology, there was no difference between negative and positive patients (p=0,366). Considering baseline HBV DNA titers, the risk of reactivation was found to be higher in patients who were positive (p<0.001). As a result; low age, baseline HBsAg positivity, moderate risk group, baseline HBV DNA positivity were associated with reactivation. Gender, immunosuppressive therapy type, preemptive antiviral therapy type, and anti-HBs titers were not associated with reactivation.