Revised classification criteria for definite APS
| Definite APS is present if at least 1 clinical criterion and 1 laboratory criterion are met: . |
|---|
| Clinical criteria |
| Vascular thrombosis |
| One or more objectively confirmed episodes of arterial, venous, or small vessel thrombosis occurring in any tissue or organ. Thrombosis must be confirmed by objectively validated criteria. For histopathologic confirmation, thrombosis must be present without significant inflammation of the vessel wall |
| Pregnancy morbidity |
| One or more unexplained deaths of a morphologically normal fetus at or beyond the 10th week of gestation with normal fetal morphology documented by ultrasonography or direct examination of the fetus; or |
| One or more premature births of a morphologically normal neonate before the 34th week of gestation because of eclampsia, pre-eclampsia, or placental insufficiency; or |
| Three or more unexplained consecutive spontaneous abortions before the 10th week of gestation with maternal anatomical or hormonal causes excluded, and paternal and maternal chromosomal causes excluded |
| Laboratory criteria |
| All laboratory criteria should be present on 2 or more occasions, at least 12 weeks apart using recommended procedures. |
| LA, detected according to the guidelines of the International Society on Thrombosis and Haemostasis (scientific subcommittee on LAs/phospholipid-dependent antibodies), or |
| aCL antibody of IgG and/or IgM isotype, present in medium or high titer (>40 GPL or MPL, or greater than the 99th percentile), measured by standardized ELISA, or |
| anti–β2-GPI antibody of IgG and/or IgM isotype, present in titer greater than the 99th percentile, measured by a standardized ELISA according to recommended procedures |
| Definite APS is present if at least 1 clinical criterion and 1 laboratory criterion are met: . |
|---|
| Clinical criteria |
| Vascular thrombosis |
| One or more objectively confirmed episodes of arterial, venous, or small vessel thrombosis occurring in any tissue or organ. Thrombosis must be confirmed by objectively validated criteria. For histopathologic confirmation, thrombosis must be present without significant inflammation of the vessel wall |
| Pregnancy morbidity |
| One or more unexplained deaths of a morphologically normal fetus at or beyond the 10th week of gestation with normal fetal morphology documented by ultrasonography or direct examination of the fetus; or |
| One or more premature births of a morphologically normal neonate before the 34th week of gestation because of eclampsia, pre-eclampsia, or placental insufficiency; or |
| Three or more unexplained consecutive spontaneous abortions before the 10th week of gestation with maternal anatomical or hormonal causes excluded, and paternal and maternal chromosomal causes excluded |
| Laboratory criteria |
| All laboratory criteria should be present on 2 or more occasions, at least 12 weeks apart using recommended procedures. |
| LA, detected according to the guidelines of the International Society on Thrombosis and Haemostasis (scientific subcommittee on LAs/phospholipid-dependent antibodies), or |
| aCL antibody of IgG and/or IgM isotype, present in medium or high titer (>40 GPL or MPL, or greater than the 99th percentile), measured by standardized ELISA, or |
| anti–β2-GPI antibody of IgG and/or IgM isotype, present in titer greater than the 99th percentile, measured by a standardized ELISA according to recommended procedures |
Adapted from Miyakis et al.1
GPL, immunoglobulin G (IgG) phospholipid units; MPL, IgM phospholipid units. (1 phospholipid unit = 1 microgram of antibody.)