Abstract Introduction Diffuse alveolar hemorrhage (DAH) involves alveolar damage and bleeding from immune or non-immune causes1. Approximately 30-40% of DAH cases are immune-mediated, including ANCA-associated vasculitis and systemic lupus erythematosus (SLE)2. We present two cases of immune-mediated DAH with refractory hypoxemia requiring V-V ECMO and combination immunosuppression with corticosteroids, rituximab, cyclophosphamide, and plasma exchange (PLEX). Both patients received anakinra for suspected hemophagocytic lymphohistiocytosis (HLH)/macrophage activation syndrome (MAS). These cases illustrate a multimodal regimen for immune DAH requiring V-V ECMO for oxygenation support. Cases The first patient was a 38-year-old man without medical history who presented to an outside hospital with arthralgias, weight loss, hemoptysis, and dyspnea. He was found to have multiple venous thromboembolisms (VTE) and was transferred to our quaternary center for V-V ECMO support. Bronchoscopy confirmed DAH, and serology confirmed granulomatosis with polyangiitis (GPA) vasculitis. The second patient was a 33-year-old man with known SLE and recently diagnosed lupus nephritis. He presented with dyspnea, chest pain, and pulmonary infiltrates. Bronchoscopy confirmed DAH. His course was complicated by VTE and refractory hypoxemia requiring V-V ECMO. Both patients started rituximab and pulse-dose steroids, followed by cyclophosphamide. After their inability to wean from V-V ECMO, they received PLEX. Complications for both included renal failure requiring renal replacement therapy and concern for HLH/MAS which was treated with anakinra. The patient with GPA vasculitis was successfully decannulated from V-V ECMO but later died from ongoing non-pulmonary hemorrhage. The patient with SLE continued to require V-V ECMO which was complicated by right heart failure, and he was ultimately palliatively decannulated and died. Discussion These cases illustrate multimodal immunosuppression with corticosteroids, rituximab, cyclophosphamide, and PLEX, along with V-V ECMO support in the setting of refractory immune-mediated DAH1,3-5. Few descriptions of this combination regimen exist in the literature, and these are rarely described in adult non-vasculitis patients2,5-8. Mortality remains high in immune DAH, and the timing and efficacy of this combination regimen (including PLEX) deserve further investigation6,7. Additionally, the use of V-V ECMO in patients with immune-mediated DAH remains a challenge given the need to balance bleeding and clotting risk as illustrated by these two cases3,4,9,10. The presence of HLH/MAS in the setting of immune-mediated DAH is rare. To our knowledge, there have been no previously described cases detailing the addition of anakinra for treatment of HLH/MAS to our patients’ aggressive combination immunosuppression, PLEX, and V-V ECMO treatment regimen11. This abstract is funded by: None
Deng et al. (Fri,) studied this question.