A case of glucocorticoid-refractory IgA vasculitis with diffuse alveolar hemorrhage: a therapeutic strategy for aberrant immunoglobulin depletion.

Diffuse alveolar hemorrhage (DAH) is a rare and severe complication of IgA vasculitis (IgAV). Although glucocorticoids and immunosuppressive agents are used for its treatment, there is no consensus on the optimal form of treatment. We herein report the case of a 53-year-old, female patient with IgAV. She was initially resistant to glucocorticoid therapy and experienced acute respiratory failure due to DAH but responded well to rituximab (RTX) and plasma exchange (PLEX). While some previous case reports have suggested that RTX or PLEX can be effective for severe IgAV, there are no reports of a combination of RTX and PLEX being used successfully to treat IgAV-associated DAH. In the model of IgAV pathogenesis proposed herein, aberrant IgA1 and IgA-specific IgG autoantibodies play a pivotal role. PLEX may facilitate the prompt removal of these circulating, aberrant immunoglobulins while RTX inhibits their further production. Consequently, a combination of RTX and PLEX may represent an effective treatment approach for severe glucocorticoid-refractory cases of IgAV.