[Incidence of humoral immunodeficiency in children with recurrent infections].

The screening of humoral immunity was performed in 6280 children with recurrent infections. The low level of immunoglobulins was detected in 287 children. The most frequently were: the decreased level of IgA (142 children), and selective IgA deficiency (78 children). The decreased level of all classes of immunoglobulins was rare. Within this group of children severe immunodeficiency diseases (Omenn syndrome, Seemanov syndrome, SCID with NK predominance or MHC class II deficiency) were diagnosed.