[Non specific immunity of children with selective IgA deficiency. Aggravating role of abnormal phenotype of alpha-1-antitrypsin (author's transl)].

Among 998 children with recurrent respiratory diseases 26 children with selective IgA deficiency were found. Three groups were considered according to IgA level in serum: group I with IgA under 0.05 g per litre; group II with IgA between 0.05 and 0.3 g per litre; group III with IgA above 0.3 and under 1 g per litre. Non specific immunity was studied in these patients including immunoglobulin levels, alpha-1-antitrypsin (A.A.T.) phenotypes, phagocytosis of staphylococcus aureus by PMN, lysozyme level, complement system. Cellular immunity was evaluated by IDR tests and rosette forming cells (RE). Only non specific immune systems were disturbed in some patients and appeared as aggravating factors in IgA deficient patients. We found: Abnormal phenotypes of ATT in 11 cases; deficiencies of engulfment in 6 cases, of bactericidal activities of PMN in 7 cases out of 16 studied; decrease of lysozyme level in 4 cases out of 17 studied; increase of IgE level in 9 cases with atopic symptoms in 7 patients. In our experience the chief aggravating factor in IgA deficient patients is abnormal phenotype of AAT.