Publication:

Post-vaccination hepatitis B seroprotection among kidney transplant recipients in Saudi Arabia: a retrospective cohort study

Background Evidence regarding post-vaccination hepatitis B virus (HBV) seroprotection among kidney transplant recipients in Saudi Arabia remains limited. This study estimated the prevalence of seroprotection and evaluated factors associated with vaccine nonresponse.

Methods This single-center retrospective cohort study included adult kidney transplant recipients followed at Prince Sultan Military Medical City, Riyadh, Saudi Arabia, who had documented hepatitis B vaccination and subsequent quantitative measurement of antibodies to hepatitis B surface antigen (anti-HBs). Seroprotection was defined as an anti-HBs concentration of at least 10 mIU/ml. Participant characteristics were compared according to seroprotection status. Multivariable logistic regression was used to evaluate associations between non-seroprotection and total number of hepatitis B vaccine doses.

Results Among 100 kidney transplant recipients, the mean (SD) age was 41.4 (15.2) years, and 66 participants (66.0%) were male. Overall, 69 recipients achieved seroprotection (69.0%; 95% CI, 59.4-77.2%), whereas 31 (31.0%) remained non-seroprotected. Vaccine dose category differed significantly by seroprotection status (p=0.014); 80.6% of non-seroprotected recipients had received only 1 to 2 doses compared with 50.7% of seroprotected recipients. In the adjusted model, no variable was independently associated with non-seroprotection. Each 10-year increase in age was associated with higher, but not statistically significant, odds of non-seroprotection (aOR, 1.44; 95% CI, 0.96-2.16; p=0.079).

Conclusions Nearly one-third of vaccinated kidney transplant recipients lacked serological protection against HBV. Routine post-vaccination anti-HBs testing and individualized booster or revaccination strategies should be considered, particularly for older recipients and those who have received fewer vaccine doses.