Table 3.

CAPS classification criteria⁵⁴

Classification	Criteria
Definite CAPS	1. Evidence of involvement of 3 or more organs, systems, and/or tissues
	2. Development of manifestations simultaneously or in <1 wk
	3. Confirmation by histopathology of small vessel occlusion in at least 1 organ or tissue
	4. Laboratory confirmation of persistent aPL
Probable CAPS	All 4 criteria except for only 2 organs, systems, and/or tissues involved
	All 4 criteria except for the absence of laboratory confirmation of aPL
	All 4 criteria except for the absence of histopathologic confirmation of small vessel occlusion
	All 4 criteria except for the development of a third event in >1 wk but <1 mo despite anticoagulation