The classification criteria for CAPS
| Classification criteria for CAPS: 1. Rapid onset, usually in less than one weeka 2. Involvement of 3 or more tissues, organs, or organ systems 3. Presence of antiphospholipid antibodies (aPL), otherwise meeting criteria for the diagnosis of APSb 4. Histopathological confirmation of microvascular ischemia |
| Definite CAPS: All 4 criteria |
| Probable CAPS: • All 4 criteria with 2 site involvementc • All 4 criteria without confirmation of serial aPL positivity • All criteria except for criteria number 4 • Progression over more than a week, particularly in the face of anticoagulation therapy |
| Classification criteria for CAPS: 1. Rapid onset, usually in less than one weeka 2. Involvement of 3 or more tissues, organs, or organ systems 3. Presence of antiphospholipid antibodies (aPL), otherwise meeting criteria for the diagnosis of APSb 4. Histopathological confirmation of microvascular ischemia |
| Definite CAPS: All 4 criteria |
| Probable CAPS: • All 4 criteria with 2 site involvementc • All 4 criteria without confirmation of serial aPL positivity • All criteria except for criteria number 4 • Progression over more than a week, particularly in the face of anticoagulation therapy |
The diagnosis of CAPS is frequently delayed, and as such the diagnosis itself may occur more than 1 week after onset; however, a review of the medical record should demonstrate the initial presentation with a rapid crescendo of new clinical manifestations.
Given the necessity to institute therapy promptly, serial positivity, as required by APS classification criteria,14 will not be available at the initial diagnosis, but if the patient survives, it should be confirmed more than 12 weeks after the initial test. Note that interruption of anticoagulant therapy is problematic in many patients and may negate the ability to repeat the LAC testing.
An imaging review with a radiologist experienced in this area is warranted as subtle evidence of multiple tissue involvement is often found on secondary imaging reviews. For example, many patients have involvement of the adrenal glands, which is frequently overlooked on initial review.