ASSOCIATION OF HUMAN FC-GAMMA-RIIA (CD32) POLYMORPHISM WITH SUSCEPTIBILITY TO AND SEVERITY OF MENINGOCOCCAL DISEASE

Phagocytosis of bacteria constitutes an important defense mechanism ag ainst invasive bacterial diseases. Efficacy of phagocytosis by polymor phonuclear neutrophils is known to vary between allotypes of Fc gamma RIIa (a class of Fc receptors for immunoglobulins that is constitutive ly expressed on neutrophils). We compared the distribution of Fc gamma RIIa-R131 and Fc gamma RIIa-H131 allotypes in 98 Slavic complement-su fficient patients with meningococcal disease with that of the allotype s in 107 healthy controls. A strong association was found between the IIa-R/R131 allotype and the development of meningococcal disease after the age of 5 years, compared with IIa-R/H131 and IIa-H/H131 allotypes (P < .03; odds ratio [OR], 2.9), A severe course of meningococcal dis ease was observed in 21 (68%) of 31 episodes in patients with IIa-R/R1 31 genotype and in 22 (54%) of 41 episodes in patients with IIa-R/H131 genotype, in contrast to eight (31%) of 26 episodes in patients with IIa-H/H131 genotype (P < .02; OR, 4.7). Our data show that individuals older than 5 years of age who have the IIa-H/H131 allotype are less s usceptible to severe meningococcal disease than are individuals with t he IIa-R/R131 or IIa-R/H131 genotype.