Respiratory and allergic disorders in children with severe and partial immunoglobulin A immunodeficiency

Immunoglobulin A deficiency (IgAD) is the most common primary immunodeficiency. Although most people with selective IgAD (sIgAD) are asymptomatic, many patients often suffer from recurrent respiratory infections and different allergic disorders. Our aim was to investigate connection between subtypes of sIgAD and incidence of respiratory and allergic disorders, as well as connection with lung function changes in children.

Children with IgAD where divided into two groups; severe IgAD in patients was defined as serum IgA level <7 mg/dL, while partial IgA deficiency diagnosis was made when serum IgA levels was higher than 7 mg/dL but at least two standard deviations (SD) below mean normal concentrations for their age. All patients were evaluated by their clinical and laboratory investigation parameters and compared to control group of children.

Group of children with IgAD, severe as well as partial, showed higher prevalence of allergic diseases and total number of infections, compared to controls. There was a statistically significant difference in lung function for peak expiratory flow (PEF), the maximal expiratory flow at 50% of the forced vital capacity (MEF50) and fraction of exhaled nitric oxide (FENO) between group of patients with severe as well as partial IgAD and control group, where children with IgAD showed reduced lung function.

Children with sIgAD are at increased risk for higher number of respiratory infections and developing allergic diseases, resulting in significantly lower pulmonary function which is related with the severity of sIgAD.