AB1850 MICROSCOPIC POLYANGIITIS WITH CONCURRENT THROMBOTIC THROMBOCYTOPENIC PURPURA: A CASE REPORT

Background Thrombotic thrombocytopenic purpura (TTP) and Microscopic polyangiitis (MPA) rarely occur in conjunction. Autoimmune TTP is caused by autoantibodies to the ADAMTS13 protein that cleaves von Willebrand factor. MPA a small-vessel vasculitis typically affects small blood vessels of lung kidney [1]. We present case concurrent which we believe could highlight pathogenetic correlation treatment overlap between two diseases. Objectives To report rare educate physicians on optimal strategies. Methods Case literature review. Results A 67-year-old patient with history stroke sickle cell trait presented emergency department due altered mental status fever. Serology admission was notable for marked acute injury anemia requiring transfusions. Urinalysis showed hematuria proteinuria. serology remarkable p-ANCA positivity at 1:80 myeloperoxidase antibody > 30 pmol/L; diagnosis made. Patient’s also thrombocytopenia nadir under 60 evidence thrombotic microangiopathy peripheral smear hemolysis labs. were reduced less than 3% functionality an inhibitor 1/0 BU, confirming TTP. Patient initiated high-dose steroids therapeutic plasma exchange (TPE) resultant normalization platelets improvement renal function. TPE discontinued, transitioned rituximab continuation steroids. The ultimately discharged home steroid taper maintenance dosing. Conclusion Per review, three other cases have been reported [2-4]. Further investigation into may be warranted. Although rare, when occurring together presentation often severe, urgent initiation critical. mainstay but usually only recommended patients anti-GBM antibodies, those high risk progression end stage disease, or unresponsive first-line therapies [1,5,6]. Rituximab, acts decrease B activity overall production, has shown reduce disease both conditions [1,5]. This suggests that, event are concurrently diagnosed, combined use conjunction induce remission more efficiently either alone. References [1] Chung SA, Langford CA, Maz M, et al. 2021 American College Rheumatology/Vasculitis Foundation Guideline Management Antineutrophil Cytoplasmic Antibody-Associated Vasculitis. Arthritis Rheumatol . 2021. doi:10.1002/art.41773 [2] Hirsch DJ, Jindal KK, Trillo AA. cytoplasmic antibody-positive crescentic glomerulonephritis microangiopathy. Am J Kidney Dis 1995. doi:10.1016/0272-6386(95)90663-0 [3] Nagai K, Kotani T, Takeuchi Successful repeated microscopic polyangitis. Mod 2008. doi:10.1007/s10165-008-0107-3 [4] Syed Mujtaba Ali Naqvi, Rachel Whittaker, Arti Saraswat, Nisarfarthi Kazimuddin, Rishi Agarwal; Rare Concurrent New-Onset Polyangiitis Thrombocytopenic Purpura 77-Year-Old Woman. Blood doi: https://doi.org/10.1182/blood-2021-148966 Acknowledgements: NIL. Disclosure Interests None Declared.