[Vaccination of splenectomized children. Antibody response to Haemophilus influenzae type b conjugate vaccine]

Twenty splenectomized children and adolescents aged four to 18 years were immunized once with a Haemophilus influenzae type b (Hib) polysaccharide tetanus toxoid conjugate vaccine. Prior to vaccination, ten of 20 patients had anticapsular antibodies below what could be considered the minimum protective level in the splenectomized (0.6 microgram per ml), whereas all obtained high antibody levels after vaccination. In addition, one infant with congenital asplenia was vaccinated at two, four, and six months of age, and was shown to respond well after the second and third injections, obtaining serum antibody concentrations of 0.84 and 10.7 microgram per ml respectively. Because asplenic individuals have an increased risk of invasive Hib infection, these data suggest that vaccination of such individuals against Hib may be justified.