The Association of Antibodies to P2 Glycoprotein I with the Antiphospholipid Syndrome: A Meta-analysis*f

The precise target of marker autoantibodies in the antiphospholipid syndrome (APS) has been controversial. Recently, the theory that surface-bound (32 glycopro tein I ((32GPI) presents a normally encrypted autoepitope and that antibodies to 02GPI (anti-(32GPI) are associated with APS, has been prominent. The literature has been searched from 1990 to 1995 (inclusive) to find studies in which: (1) anti-p2CPI antibodies were measured and, (2) adequate clinical data describing the patients were included. These conditions were met in four studies, from August 1992 to December 1995, in which patient samples ranged from 15 to 39 cases, the total of the four studies being 90 cases. Applying the diagnostic criteria of 5=2 clinical manifes tations of APS, 65 cases had APS while 25 did not. For the group with APS, 58/65 (89 percent) were anti-(32GPI (+); among those who did not meet the criteria, 11/25 (44 percent) were anti-(32GPI (+) (p < 0.0001). The presence of either the primary (1°) or secondary (2°) form of APS made no difference in association with anti-P2GPI; 13/16 (81 percent) patients with 1 ° APS and 45/49 (92 percent) with 2 ° AP