The classification criteria for definite antiphospholipid syndrome (APS) - the so-called Sapporo criteria - have been revised by an expert workshop preceding the 11th International Congress on Antiphospholipid Antibodies (Miyakis et al. 2006). The traditional defined and maintained laboratory criteria have been lupus anticoagulant (1st criterion) and anticardiolipin antibodies (aCL, IgG and IgM isotype; 2nd criterion). Now anti-β2-glycoprotein I autoantibodies of IgG and IgM isotype have been added in the revised criteria:

3rd laboratory criterion: Anti-β2-Glycoprotein I antibody of IgG and/or IgM isotype in serum or plasma (in titer > the 99th percentile), present on two or more occasions, at least 12 weeks apart, measured by a standardized ELISA, according to recommended procedures (Reber et al 2004).

The anti-β2GPI assay shows higher specificity than aCL for APS diagnosis. Furthermore, in some 3-10 % of APS patients, anti-β2-glycoprotein I may be the only test found positive. Laboratories measuring anti-β2GPI are encouraged to standardize the type of plates, purity, concentration and source of the antigen.

DIARECT antigen Cat.No. 14900 β2-Glycoprotein I (Apolipoprotein H) accomplishes those high specifications and has been successfully implemented in diagnostic devices since many years. Contact now for your f.o.c. evaluation sample: orders@diarect.com !

Ref.:
Miyakis, S. et al. (2006) International consensus statement on an update of the classification criteria for definite antiphospholipid syndrome (APS). J Thromb Haemost 4, 295-306.
Reber, G. et al. (2004) Proposals for the measurement of anti-beta2-glycoprotein I antibodies. Standardization group of the European Forum on Antiphospholipid Antibodies. J Thromb Haemost 2, 1860-2