Classification criteria for catastrophic APS
| Classification criteria . |
|---|
| 1. Evidence of involvement of 3 or more organs, systems, and/or tissues |
| 2. Development of manifestations simultaneously or in less than a week |
| 3. Confirmation by histopathology of small-vessel occlusion* |
| 4. Laboratory confirmation of aPLs† |
| Definite catastrophic APS |
| i. All 4 criteria present |
| Probable catastrophic APS |
| i. All 4 criteria, except only 2 organs, systems, and/or tissues involved |
| ii. All 4 criteria, except for the absence of laboratory confirmation of aPLs |
| iii. Diagnostic criteria 1, 2, and 4 |
| iv. Diagnostic criteria 1, 3, and 4, with the development of a third event >1week but within 1 mo of presentation, despite anticoagulation |
| Classification criteria . |
|---|
| 1. Evidence of involvement of 3 or more organs, systems, and/or tissues |
| 2. Development of manifestations simultaneously or in less than a week |
| 3. Confirmation by histopathology of small-vessel occlusion* |
| 4. Laboratory confirmation of aPLs† |
| Definite catastrophic APS |
| i. All 4 criteria present |
| Probable catastrophic APS |
| i. All 4 criteria, except only 2 organs, systems, and/or tissues involved |
| ii. All 4 criteria, except for the absence of laboratory confirmation of aPLs |
| iii. Diagnostic criteria 1, 2, and 4 |
| iv. Diagnostic criteria 1, 3, and 4, with the development of a third event >1week but within 1 mo of presentation, despite anticoagulation |
From Cervera et al.79
Vasculitis may coexist, but significant thrombosis must be present as well.
Laboratory detection requires evidence of a lupus anticoagulant, medium-high titer anti-cardiolipin antibodies, or medium-high titer anti–β2-glycoprotein I antibodies on 2 occasions at least 12 weeks apart (our recommendation for medium-to-high titer is >40 units/L).