Diffuse alveolar hemorrhage associated with proteinase 3-specific anti-neutrophil cytoplasmic antibodies

A 31-year-old man was referred to our hospital for the management of progressive diffuse alveolar hemorrhage associated with renal dysfunction. Leukocytoclastic vasculitis was shown by skin biopsy and crescentic glomerulonephritis was also detected, in addition to positivity for proteinase 3-specific anti-neutrophil cytoplasmic antibodies (PR3-ANCA). The patient was diagnosed as a rare case of PR3-ANCA-positive pulmonary-renal vasculitic syndrome without granulomatous lesions. There was a good response to combination therapy with steroids and cyclophosphamide.