[Diagnosis of IgA deficiency--a simple semiquantitative method]

Defective IgA production resulting in decreased or deficient levels is one of the most commonly occurring derangements of the immune system. Therapy consisting in the administration of gammaglobulin preparations is strictly contraindicated in cases of zero or virtually zero values of IgA as there is a high probability of anti-IgA autoantibody formation. The authors present a simple yet very sensitive method based on the principle of ELISA by which patients with a deficit can be differentiated from those with a reduced IgA level. The level is determined on microdisks and no measuring equipment is required for reading the results.