IgA deficiency in Czech healthy individuals and selected patient groups.

BACKGROUND

Selective IgA deficiency (IgAD) is the most common immunoglobulin deficiency with a variety of clinical manifestations. The frequency of IgAD differs depending on the ethnic origin and clinical symptoms of investigated persons.

METHODS

The prevalence of IgAD (serum IgA level <0.05 g/l) was determined in 5,310 Czech blood donors, 10,326 patients who had undergone immunological investigation, and 246 first-degree relatives of IgAD and common variable immunodeficiency (CVID) patients.

RESULTS

IgAD was detected in 13 (1/408; 0.24%) of the blood donors. The prevalence of IgAD was increased both in children (48/3,113; 1.5%) and adults (33/3,824; 0.9%) referred for frequent respiratory tract infections (in both cases p<0.001) compared to the healthy population. The frequency of IgAD was 12/189 (6%) in first-degree relatives of IgAD patients and 9/57 (16%) in relatives of CVID patients, with the highest frequency observed in children of CVID patients.

CONCLUSIONS

The prevalence of IgAD in the Czech healthy population is comparable to that in other Caucasians. The frequency is increased in children with recurrent respiratory tract infections and especially in relatives of patients with immunoglobulin deficiencies.