IgA anti-ß2 glycoprotein I antibodies: Experience from a large center.

ABSTRACT

OBJECTIVE: IgG and IgM antibodies directed at ß2-glycoprotein I are included in the classification criteria for the antiphospholipid syndrome (APS) while the IgA antibodies against ß2-glycoprotein I (IgA aß2GPI) are not. Conflicting data about the significance of IgA aß2GPI and APS manifestation can be found and more studies are necessary in order to define the diagnostic value of IgA aß2GPI. In the present article, we investigated the possible role of IgA aß2GPI as marker of APS. METHODS: A cohort of 314 patients with APS and systemic autoimmune disease was investigated for the presence of IgA aß2GPI and its association with clinical manifestation of APS. RESULTS: Eighty-nine patients presented IgA aß2GPI, 68 cases associated with others antiphospholipid antibodies (aPL) and in 21 cases being the only aPL present. In primary APS IgA aß2GPI are highly coincidental with other aPL (92,2%) while most of the isolated IgA aß2GPI were present in the SLE group (16/21). No association between IgA aß2GPI and APS manifestations thrombosis and pregnancy morbidity was found, while a positive association between IgA aß2GPI and the presence of anti-nDNA, anti-RNP, anti-Sm, anti-SSA, anti-SSB antibodies was encountered. CONCLUSION: Our study does not show association between IgA aß2GPI and APS manifestations and does not support the inclusion of IgA aß2GPI as a classification criteria for APS.