OUTCOME OF PATIENTS WITH NON-CRITERIA MANIFESTATIONS OF PRIMARY ANTIPHOSPHOLIPID SYNDROME TREATED WITH IMMUNOSUPPRESSANTS -A SINGLE-CENTER STUDY

PV022 / #697 Poster Topic: AS03 - Antiphospholipid Syndrome Background/Purpose Background: The frequency of non-criteria manifestations in Primary antiphospholipid syndrome (PAPS) is 24%. The efficacy of immunosuppressants in patients with above condition is not certain due to paucity of evidence. Objectives: To evaluate the outcome of patients who have been treated with immunosuppressive drugs for treatment of non-criteria manifestations of PAPS. Methods Patients with the diagnosis of APS or probable APS, attending our clinics between 2010 to 2024 were screened. Among these, those satisfying the APL domain of ACR/EULAR 2023 criteria and had at least 1 non criteria manifestation not attributable to any other defined CTD or disease and have been treated with immunosuppressive therapy were included. The non-criteria manifestations included all the ones mentioned in ACR/EULAR criteria or autoimmune haemolytic anemia (AIHA) and catastrophic APS (CAPS). Data regarding clinical presentation, laboratory abnormality, treatment and response were included. The primary outcome was the clinical improvement or resolution of the presenting manifestation after initiation of therapy. The results are depicted descriptively. Results A total of 44 patients 28 females, mean age 38±13 (SD) years satisfied the inclusion criteria. The most common non-criteria manifestation was thrombocytopenia (24, 54 %) followed by AIHA (12,27%) (Table 1). Rituximab was the most common immunosuppressant used in 19(43%) followed by mycophenolate (18 (40%). 90% received antiplatelet and anticoagulants. During a median follow-up of 32 months (IQR: 20-63), 80% patients responded to treatment. The response was sustained in 59% at the last follow-up. The best response was noted among patients with thrombocytopenia. n=20(83%) of thrombocytopenia responded to immunosuppressive treatment including rituximab (n=9, 81%), mycophenolate (n=5,85%) and Azathioprine (n=6, 66%). Response rates of all manifestations is depicted in Table 2. Major adverse events included death in 2 patients due to sepsis and pneumocystis carinii pneumonia in patients receiving rituximab and 1 death due to sepsis, disseminated TB, Ca breast in patients receiving MMF. Table 1. Table 2: Comparison of response to therapy in patients receiving Rtx and mycophenolate/azathioprine Conclusions Among the patients with PAPS with non-criteria manifestation, the best response to immunosuppression was observed in those presenting with AIHA and thrombocytopenia. All manifestations except LAHPS and skin ulcers showed similar response with rituximab as well as mycophenolate/azathioprine.