Selective IgA Deficiency

This chapter discusses the background, diagnosis, treatment, and prognosis for selective IgA deficiency. Selective IgA deficiency is a primary antibody immunodeficiency characterized by significantly decreased (less than 7 mg/dL) or lack of serum IgA in the absence of any other immunodeficiency disorder in an individual older than 4 years of age. Serum levels of IgG and IgM are normal in patients with selective IgA deficiency. The majority of patients with IgA deficiency is asymptomatic and requires routine follow-up and education regarding their disease. Symptomatic patients typically present with recurrent sinopulmonary infections, autoimmune disease, or gastrointestinal disorders (e.g. celiac disease, inflammatory bowel disease, nodular lymphoid hyperplasia). Symptomatic patients with recurrent sinopulmonary disease are aggressively treated according to the underlying condition (e.g. allergy, asthma, chronic rhinosinusitis). Patient with severe symptoms or coexisting antibody deficiency may require treatment with antibiotics and/or immunoglobulin replacement.