MPO and granulomatosis with polyangiitis: The second patient was MPO positive with a clinical phenotypic presentation compatible with GPA (rhinosinusitis, finding of granulomatous inflammation on lung biopsy) after 19 months presented worsening of sinusitis, bilateral pulmonary thickening and urinary abnormalities; on renal biopsy, florid crescents were found on 27% of non-sclerotic glomeruli.