Splenectomy for refractory thrombocytopenia in the antiphospholipid syndrome.

OBJECTIVE: Thrombocytopenia, usually mild, is one of the clinical criteria of the antiphospholipid syndrome (APS). Rarely, this disorder requires treatment and, due to the shared characteristics with idiopathic thrombocytopenic purpura (ITP), similar rules are followed. We report our experience in patients who required splenectomy after being refractory to steroids and immunosuppressive therapy.
METHODS: Fifty-five APS patients with a platelet count of < 100 x 10(9)/l at least twice were analysed retrospectively. Therapeutic response or remission was considered when the platelet count was > 100 x 10(9)/l after 1 month and with no relapse on stopping or tapering the steroid dose. No response or refractory disease was defined as an absence of increase in platelet count, a total count that never exceeded 50 x 10(9)/l during treatment or when the dose requirements were such that the patient developed serious side-effects.
RESULTS: Fifty patients were classified as having secondary APS associated with systemic lupus erythematosus (SLE) and five were identified as primary APS (PAPS). Splenectomy was performed in 11 cases (20%), two PAPS and nine SLE-APS, with an average time of 28 +/- 9 months after the development of thrombocytopenia. Eight patients were initially characterized as ITP (six SLE-APS, two PAPS) with an average time of 4.4 +/- 1.1 yr until the APS diagnosis. All but two were responsive to splenectomy.
CONCLUSION: Splenectomy was required in 11 (20%) of the patients with APS-associated thrombocytopenia. There was a high rate of good and long-term response.