A retrospective review of serological response to the 2.0 ml intramuscular four doses schedule of hepatitis B vaccine in chronic kidney disease patients

Background and Aim: Chronic kidney diseases (CKD) patients, particularly those on hemodialysis, are at high-risk to acquire hepatitis B virus (HBV) infection. They are vaccinated with four doses, 2.0 ml each, of HBV vaccine at 0, 1, 2, and 6 months. However, Indian data are limited on vaccine-induced seroconversion in CKD patients. We retrospectively reviewed the vaccine response and their sustenance with 2.0 ml four-dose schedule in CKD population. Methods: We included unvaccinated adult CKD patients with glomerular filtration rate (GFR) < 60 ml/min. Those with hepatitis C or HIV coinfection, post-organ transplant, presence of malignancy, or immunosuppressive medication were excluded. Anti-HBs antibody titers were measured after one month of the fourth dose followed by once a year thereafter. We used two different types of antibody quantitative assay, depending upon their availability. The limit of detection for antibody assay was 3-500 mIU/mL and 3-1000 mIU/mL. Antibody titers reported as >500 or >1000 mIU/mL were counted as 500 or 1000 respectively. Seroconversion was defined by the presence of detectable anti-HBs antibodies and seroprotection was defined as titer ≥10 mIU/mL. Results: We included 208 patients (71.9% males; age 44 [33-55]; CKD stage II/III/IV/V were 1.4%/7.2%/26.4%/64.9%; 46% on hemodialysis). Antibody titer was 124 (12-500) at 3 (2-8) months after the fourth dose. Seroconversion was seen in 174 (83.7%) and their antibody titer was 328 (28-500) mIU/mL; 161 of them (92.5%) had achieved seroprotection. Overall, 161 of 208 (77.4%) had achieved seroprotection. The median anti-HBs antibody levels at ≤6, 7-12, and 13- 24 months after the fourth doses were 116, 478, 43, and 70 mIU/ml respectively. Age, BMI, stage of CKD, serum albumin, and dialysis status had no impact (p<0.05) on the vaccine response. Conclusion: Indian population with CKD shows good and sustained responses to 4 dose regimens of the hepatitis B vaccine.