CIRCULATING IMMUNE-COMPLEXES IN IGA DEFICIENCY

  • 1 January 1979
    • journal article
    • research article
    • Vol. 38  (1) , 45-51
Abstract
Circulating immune complexes (IC) were demonstrated in patients with serum Ig[immunoglobulin]A deficiency. Of 31 IgA-deficient patients, 16 had serum IC detected by solid phase Clq, [q fragment of complement component 1] radio-immunoassay for IgG class complexes. Presence of cryoglobulins (13 of 31 patients) and increased polyethylene glycol precipitation (10 of 30 patients) provided additional evidence for the presence of IC. Fourteen patients were asymptomatic but 7 had clinical evidence of disease which possibly was IC mediated: 2 with glomerulonephritis, 3 with polyarthritis, 1 with vasculitis and 1 with thyroiditis. Serum IC remained detectable in multiple samples over several months but this correlated poorly with the presence or absence of disease. Serum antibody [Ab] to IgA was detected in 15 of 31 patients. There was no direct relationship between the presence of IC and level of serum anti-IgA Ab; this Ab was present in the IC isolate in 8 patients. A considerable portion of the IC load in IgA deficiency may result from defective antigen exclusion at the level of the mucosa.