A child present with recurrent episodes of sinopulmonary infection by bacteria with polysaccharide rich capsule. Deficiency of which of the following immunoglobulin subclasses should be specifically investigated?
IgA
IgG1
IgG2
IgA + IgG2
Ans. is 'd' i.e., IgA+IgG2(Ref: Jawetz, 27th/e, p. 149)* IgG2 immunodeficiency is the most common subclass disorder associated with recurrent infections by polysaccharide encapsulated bacteria. Such infections are more frequent in patients with associated IgA deficiency.
Immunology