IgG2/IgG4 subclass deficiency in a patient with chronic mucocutaneous candidiasis and bronchiectases

Abstract
A 22-year-old man with chronic mucocutaneous candidiasis (CMC) and hypothyroidism developed severe bronchiectases following recurrent bronchopneumonia. Immunological investigations revealed IgG2/IgG4 subclass deficiency and absence of antibodies against pneumococcal and Haemophilus polysaccharides. Under regular immunoglobulin substitution every 3 weeks pulmonary symptoms improved markedly.