4710 CYCLOPHOSPHAMIDE INDUCTION TREATMENT IN ANCA-ASSOCIATED VASCULITIS WITH RENAL AND PULMONARY INVOLVEMENT: OUTCOMES AND SIDE EFFECTS

Abstract Background and Aims ANCA associated vasculitis are necrotaizing vasculitis of small and medium vassels - which cause organ damage. They are relatively rare diseases with an estimated prevalence of 200–400 cases per million people [1]. Pauci-immune necrotizing and crescentic glomerulonephritis (GN) is a frequent component of ANCA-associated vasculitis that can cause rapidly progressive Acute Kidney Injury (AKI). Less frequently, it can cause low progressive Chronic Kidney Disease (CKD) [2]. Combination therapy of steroids and cyclophosphamide has improved 5-years survival up to 70-90% but it can cause serious side effects including infectious episodes [3], bone marrow suppression and myelodysplasia. We present a case highlighting treatment modalities and our decision making. Method Our retrospective study analyzes the case of a 63-year-old male presenting with progressive dyspnea and hemoptysis. A chest CT suggested diffuse alveolar hemorrhage. The blood tests showed onset of AKI with 7.68 mg/dl serum creatinine (normal values 0.72-1.25), mild proteinuria and hematuria. A kidney and pulmonary vasculitis was suspected and the c-ANCA serum value was elevated at >500 IU/ml. Three cycles of Plasma Exchange (PEX) were performed and methylprednisolone was given (500 mg for 3 days, 1 g on the 4th day) followed by cyclophosphamide boluses of 1 g/week for 4 weeks. Broad-spectrum antibiotics and antifungal therapy was administered to prevent secondary infections. Due to the further worsening of the renal function, three hemodialysis treatments and a cascade filtration were performed continuing with cyclophoshamide 1 g/day orally and methylprednisolone 60 mg/day. Cyclophosphamide therapy was discontinued due to thrombocytopenia and progressive leukopenia. Filgastrim 30MU/0.5 ml was administered for five days until the resolution of the pancytopenia when cyclophosphamide 50 mg 2cp+1cp was resumed. Results A one-month follow-up CT showed reduction in hemorrhagic opacities and the c-ANCA level was significantly reduced. Steroid dosing was progressively reduced and the patient was discharged with methylprednisolone 16mg 2cp+1/2cp tapering over 6 months and cyclophosphamide 50 mg 2cp+1cp. Serum creatinine levels improved from 2.64 mg% at discharge to 1.6 mg% at follow up. Conclusion When treating c-ANCA vasculitis with corticosteroids and cyclophosphamide, routine evaluation of complete blood count parameters is necessary to prevent bone marrow toxicity. We contin