Increased percentages of autoantibodies in immunoglobulin A-deficient children do not correlate with clinical manifestations.

摘要

IgA deficiency (IgAD) is frequently associated with autoimmune phenomena. The aim of this study is to evaluate the frequency of 22 different autoantibodies in 60 patients with IgAD and to examine the physical and other laboratory findings of the suspected cases for autoimmune diseases. The evaluated autoantibodies were Anti-nuclear antibody (ANA) profile (autoantibodies against RNP/Sm, SS-A, Ro-52, SS-B, Scl-70, Pm-Scl, Jo-1, centromere B, PCNA, dsDNA, nucleosomes, histones, ribozomal P-protein, AMA-M2), anti-cardiolipin IgG and IgM, anti-neutrophilic cytoplasmic antibodies (ANCA), rheumatoid factor (RF), anti-thyroglobulin (anti-T) and anti-thyroid microsomal antigen (anti-M) and direct cooms test. Forty-one healthy children were included as a control group. ANA titers < or = 1:80 were accepted as normal and titers > or = 1:80 are accepted as positive. In ANA screening, 14 patients showed positivity in different titres. Seven of them were equal to or below 1:80. The other seven patients (11.6%) had positive ANA titers (>1:160) whereas three of them had anti-dsDNA, anti-histon and anti-centromer antibodies. These patients did not have any clinical and laboratory signs of autoimmune diseases. ANA positivity was found higher in IgA deficient children (p < 0.05) compared to controls. RF and pANCA were found positive during follow-up of two different selective IgAD patients. IgG and IgM antibodies against cardiolipin, direct coombs, anti-T and anti-M tests were not found positive in any subjects. In conclusion, increased frequency of autoantibodies in IgAD patients may often be observed. However, the detection of autoantibodies do not show or predict whether this patient will develop an autoimmune disease.