Abstract
The present study was undertaken to find out if the seroconversion rate for hemodialysis (HD) patients was enhanced by intradermal (ID) inoculation of recombinant hepatitis B (HB) vaccine.
Thirtyfive HBs-Ag, -Ab, HBc-Ab negative HD patients were divided into three groups: 14 patients (Group I) received 5μg of HBs Ag ID every two weeks, 13 patients (Group II) were given 2.5μg of HBs vaccine ID every two weeks, 5 times, then every week. The remaining 8 patients (Group III) were injected intramuscularly (IM), with 10μg of HBs Ag every four weeks 5 times then with 5μg ID, every two weeks until complete seroconversion.
Antibody response to IM injection was poor and only 37.5% of the patients had developed anti-HBs antibodies at a titer of 10mIU/ml or more by 16 weeks after the start of immunization. However, this poor response was improved by ID injection. The time of seroconversion was significantly earlier and the rate of response was higher in Group I.
The poor response in Group II was markedly improved by doubling the inoculation rate. Overall 100% seroconversion was finally obtained by multiple ID injections. However, the anti-HBs antibody titers were lower in all patients and declined in some patients after discontinuation of immunization. We feel that the ID route remains a useful and cheaper method of obtaining prophylaxis against HB in high risk HD patients but it would seem to be prudent to monitor these patients serially to assess the persistence of anti-HBs antibody in the serum.
