Intradermal vs intramuscular vaccine against hepatitis B infection in dialysis patients: a meta-analysis of randomized trials

Chronic dialysis patients are at risk of contracting hepatitis B virus infection and have a diminished immune response to hepatitis B virus vaccine. Recent reports support intradermal administration of hepatitis B virus vaccine in patients on regular dialysis but the efficacy and safety of this approach remain unclear. We conducted a meta-analysis of randomized, controlled clinical trials to compare seroprotection achieved by intradermal vs intramuscular hepatitis B vaccine, in patients on maintenance dialysis. Meta-analysis of data from 718 adults (14 trials) on long-term dialysis demonstrated that intramuscular hepatitis B vaccination was less likely to achieve seroprotection than intradermal vaccination, the pooled odds ratio was 0.454 (95% CI, 0.3; 0.67), P = 0.001. The test of study heterogeneity was not significant. This difference did not persist during follow-up (6-60 months after completing vaccine schedule), the pooled odds ratio being 0.718 (95% CI, 0.36; 1.47), NS. Some evidence of significant heterogeneity including publication bias was present but stratified analysis in various subgroups showed that this issue did not meaningfully change our results. Intradermal hepatitis B vaccine was safe and well tolerated. We conclude that intradermal hepatitis B vaccine induces a superior response rate compared to intramuscular route at completion of vaccine cycle, despite a lower vaccine dose. No significant advantage was found over longer follow-up. It remains unclear whether the higher seroprotection rate achieved with intradermal route translates into a lower frequency of de novo hepatitis B among patients on maintenance dialysis.