[Vaccination against hepatitis B virus. Value of intradermal administration in dialysed patients non responsive to intramuscular approach].

Objectives: Approximately 16-27% of dialysis patients (DP) have no detectable antibodies after 5 intramuscular injections of hepatitis B vaccine and represent a group at high risk to contract hepatitis B virus. We report the efficacy of the intradermal route of a recombinant hepatitis B vaccine (r-HBV) in non-responsive dialysis patients in our dialysis unit.

Methods: Intradermal vaccinations were performed in 20 dialysis patients (mean age 62 years) non-responsive to the intramuscular injections (mean 6.8). Five micrograms of r-HBV (Engerix B, SK and F) were administered intradermally every two weeks (maximum 70 micrograms) until a level of anti-HBV antibodies (anti-HBs) arbitrarily choosen of > or = 230 mUI/ml was attained. Anti-HBs was determined after the fourth and subsequent intradermal injections (IMX, Abbott).

Results: Fourteen dialysis patients (70%) developed anti-HBs > 10 mUI/ml (geometric mean titers of 330 mIU/ml). Among these, 9 developed seroprotective levels before the fifth injection. Five patients developed anti-HBs > or = 1000 mUI/ml and 6 others developed anti-HBs > or = 230 mUI/ml. After the intradermal injections were discontinued, 11 patients were monthly monitored for at least 3 months, and 6 for one year. The geometric mean antibody level was at 3 months: 157 (n = 11), at 6 months: 122 (n = 8), at nine months: 117 (n = 6), and at 12 months: 66 mIU/ml (n = 6). The age and the sex, haemodialysis duration, albumin levels or treatment by erythropoietin did not seem to play a role in appearance of anti-HBs.

Conclusions: Our experience in 20 dialysis patients shows that repeated low-dose intradermal injections resulted in long-term seroprotection in a substantial number of dialysis patients non-responsive to the intramuscular vaccinations.