Protection against meningococcal serogroup ACYW disease in complement-deficient individuals vaccinated with the tetravalent meningococcal capsular polysaccharide vaccine

Individuals with properdin, C3 or late complement component deficiency (LCC D) frequently develop meningococcal disease. Vaccination of these persons h as been recommended, although reports on efficacy are scarce and not conclu sive. We immunized 53 complement-deficient persons, of whom 19 had properdi n deficiency, seven a C3 deficiency syndrome and 27 had LCCD with the tetra valent (ACYW) meningococcal capsular polysaccharide vaccine. Serological st udies were performed in 43 of them. As controls 25 non-complement-deficient relatives of the complement-deficient vaccinees and 21 healthy non-related controls were vaccinated. Post-vaccination, complement-deficient individua ls and controls developed a significant immunoglobulin-specific antibody re sponse to capsular polysaccharides group A, C, Y, W135, but a great individ ual variation was noticed. Also, the proportion of vaccinees of the various vaccinated groups with a significant increase in bactericidal titre (assay ed with heterologous complement) was similar. Opsonization of meningococci A and W135 with sera of the 20 LCCD individuals yielded in Il (55%) and eig ht (40%) sera a significant increase of phagocytic activity after vaccinati on, respectively. Despite vaccination, four complement-deficient patients e xperienced six episodes of meningococcal disease in the 6 years post-vaccin ation. Four episodes were due to serogroup B, not included in the vaccine. Despite good response to serogroup Y upon vaccination, disease due to serog roup Y occurred in two C8 beta-deficient patients, 3.5 and 5 years post-vac cination. These results support the recommendation to vaccinate complement- deficient individuals and to revaccinate them every 3 years.