Diagnostic algorithm of pulmonary vasculitis that correlates diagnostic images with clinical and lab findings (Mahmoud et al. modification) (44). Ab, antibodies; ANCA, antineutrophil cytoplasmic antibody; p-ANCA, perinuclear immunofluorescence ANCA; c-ANCA, cytoplasmic immunofluorescence ANCA; COPD, chronic obstructive pulmonary disease; DAH, diffuse alveolar haemorrhage; GBM, glomerular basement membrane.