Relapsing catastrophic antiphospholipid syndrome potential role of microangiopathic hemolytic anemia in disease relapses

Objective: To analyze the clinical and laboratory characteristics of patients with catastrophic antiphospholipid syndrome (APS) who suffer relapses.

Methods: We analyzed the Web site--based international registry of patients with catastrophic APS ("CAPS Registry") http://infmed.fcrb.es/es/web/caps and selected those cases that relapsed.

Results: Relapses were reported in 9 of 282 (3.2%) patients with catastrophic APS. A total of 35 episodes of catastrophic APS were found: 6 patients presented 2 relapses, 2 patients suffered 3 relapses, and 1 patient developed 17 relapses. However, the last patient was not included in the statistical analysis because his clinical and immunologic characteristics were not fully described. Therefore, a total of 18 episodes were analyzed. In 9 (50%) episodes, a precipitating factor was identified. The most frequent precipitating factor, found in 5 (28%) episodes, was infection. Brain, kidney, heart, and lung were the most common organs involved. Laboratory features of microangiopathic hemolytic anemia (MHA) were present in 13 of 18 (72%) episodes (definitive in 9, corresponding to 4 patients, and probable in 4, corresponding to 2 patients). Three relapses did not present with features of MHA and in the remaining 2 these data were not reported. The mortality rate was 38%.

Conclusions: Although relapses are rare in patients with catastrophic APS, these results support the hypothesis that an association between MHA and relapsing of catastrophic APS could be present.