title: A prospective study demonstrating an association between plasma IgG2 concentrations and susceptibility to otitis media in children.
abstract: Plasma IgG subclass levels of 20 children, 12 and 32 months of age, who were susceptible to acute purulent otitis media, were compared with those of 20 age-matched control children. The IgG2 levels were significantly lower in the otitis-prone group, with a mean of 0.58 +/- 0.30 g/l at 12 months of age (controls 0.85 +/- 0.39) and 0.82 +/- 0.30 at 32 months of age (controls 1.38 +/- 0.49). Otitis-prone children with IgG2 levels less than or equal to 0.58 g/l (at 12 months of age) were found to suffer from Haemophilus influenzae infections 2.6 times as often as those with IgG2 levels greater than 0.58 g/l. On the other hand pneumococci were found 1.9 times as often in the group with IgG2 level greater than 0.58 g/l, as in the group with IgG2 level less than or equal to 0.58 g/l. Otitis proneness seems partly to be due to an immunological incompetence of IgG2, which also influences the bacterial spectrum of the infections.
mesh_terms: D000208:Acute Disease; D004198:Disease Susceptibility; D006192:Haemophilus Infections / Q000276:immunology; D006193:Haemophilus influenzae / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis*; D007223:Infant; D010033:Otitis Media / Q000209:etiology* / Q000276:immunology; D011008:Pneumococcal Infections / Q000276:immunology; D011446:Prospective Studies
chemical_list: D007074:Immunoglobulin G