SFTPD and necrotizing vasculitis: The main findings of the present study were: 1) in both SAL and PA, VV improved EL and oxygenation compared to VCV; 2) in SAL, VV was associated with lower IL-6 expression in lung tissue than VCV and increased surfactant protein-D expression compared to NV; 3) in PA, VV reduced perivascular edema, septum neutrophils, necrotizing vasculitis, and ultrastructural lung damage, with no significant difference in blood CFU counts, compared to VCV.