Background: The role of circulating immunoglobulin D is still unclear. There are many data treating about serum IgD levels in different immunological diseases, but they give no answer for the question about the mechanisms of regulation of this isotype synthesis.
Methods: Serum of 18 IgA-deficient children was investigated to asses immunoglobulin D levels. As a controls, serum of 18 nonimmunodeficient females was used.
Results: There was a big disparity of serum IgD levels in the control group. Serum IgD levels in IgA-deficient children were found above 4 times below the levels observed in controls (p < 0.05). No correlation between serum IgD levels and the levels of IgM, IgG and the age in this group of patients was observed.
Conclusion: Decreased serum IgD levels in children with Immunoglobulin A-deficiency may suggest the existence of similar regulatory mechanism of these isotypes.