#271 The nexus between TMA/TTP, MIS-C, and SLE

Abstract

Abstract Background and Aims The long-term complications of COVID-19 infection & Multisystem inflammatory syndrome in children (MIS-C) on immune system are still unknown, however there're reports on development of autoimmune disease, highlighting their immune-related nature. MIS-C can induce Thrombotic Microangiopathy (TMA), by inducing endothelial dysfunction, platelet activation, & microthrombi formation, whereas SLE induces TMA/Thrombotic thrombocytopenic purpura (TTP), with ADAMTS13 activity < 10%, or 2ry TMA with ADAMTS13 activity ≥ 10%, where SLE/TTP carries a bad prognosis. Method Our case is one of its kind, where a 12-year- old girl, who was previously infected with SARS-CoV-2, presented with new-onset SLE, associated MIS-C & 2ry TMA/TTP. She presented with convulsions, oliguria, heart failure, impaired kidney function, microangiopathic hemolytic anemia, pancytopenia, highly elevated LDH, & was diagnosed as TMA. Results COVID serology was +ve for IgG, & -ve for IgM, & -ve SARS-CoV-2 PCR, a diagnosis of MIS-C was postulated. Further investigations revealed low C3, C4, +ve ANA, anti-ds DNA & anti-phospholipid Antibodies. Brain imaging showed left cerebellar calcification. Echocardiography showed biventricular dysfunction with EF 30%, where the diagnosis of SLE according to Euler/ACR criteria was confirmed, with 2ry TMA. Emergency hemodialysis, PRBCs transfusion, pulse steroid with total plasma exchange (TPE), were initiated without marked improvement. Rituximab was started on 4th day, but she had generalized convulsion, arrythmia & sudden death occurred. Results of ADAMTS13 activity was < 1%, with +ve autoantibodies, so diagnosis of TMA/TTP was confirmed. Conclusion TMA are a diverse group of disorders that causes microvasculature thrombosis, which is inherited, or acquired 2ry to SLE or COVID-19 infection, where high index of suspicions should be raised for early diagnosis and prompt management, meanwhile COVID-19 infection can induce the development of autoimmune diseases. Herein we raise the question of cause of TMA/TTP, was it 2ry only SLE, or to the previous COVID-19 infection & MIS-C, and if this SLE itself was 2ry also to the previous COVID infection, or all it was by chance?