Alveolar Hemorrhage, a Rare and Life-Threatening Complication of Catastrophic Antiphospholipid Syndrome

Table 1

Preliminary criteria for the classification of catastrophic antiphospholipid syndrome (CAPS) [3].

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(1) Evidence of involvement of three or more organs, systems, and/or tissues^a

(2) Development of manifestations simultaneously or in less than one week

(3) Confirmation by histopathology of small vessel occlusion in at least one organ or tissue^b

(4) Laboratory confirmation of the presence of anti-phospholipid antibodies (lupus anti-coagulant and/or anti-cardiolipin antibodies)^c

Definite CAPS:

 (i) All four criteria

Probable CAPS

 (i) All four criteria, except for only two organs, systems, and/or tissues involved

 (ii) All four criteria, except for the absence of laboratory confirmation owing to the early death of a patient never tested for anti-phospholipid antibodies before the CAPS

 (iii) Criteria (1), (2), and (4)

 (iv) Criteria (1), (3), and (4) and the development of a third event between one week and one month after presentation, despite anticoagulation

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Note: given that many times biopsy and histological confirmation of small vessel occlusion cannot be obtained due to the critical condition of the patients, a proposal has been made to substitute the “histopathology criteria” by the exclusion of other diagnoses. ^aUsually clinical evidence of vessel occlusions, confirmed by imaging techniques when appropriate; renal involvement is defined by a 50% rise in serum creatinine, severe systemic hypertension (>180/100 mm Hg), and/or proteinuria (>500 mg/24 h). ^bFor histopathological confirmation, significant evidence of thrombosis must be present, although vasculitis may coexist occasionally. ^cIf the patient had not previously been diagnosed as having an APS, the laboratory confirmation requires that the presence of anti-phospholipid antibodies must be detected on two or more occasions at least 12 weeks apart (not necessarily at the time of the event), according to the proposed preliminary criteria for the classification of definite APS.