[A case of recurrent bilateral pneumonia with fever. Diagnosis: microscopic polyangiitis].

Microscopic polyangiitis (MPA) is a rare systemic disease that usually presents as a pulmonary-renal syndrome. We describe 35-year-old men who presented with hemoptysis and bilateral alveolar opacities of the upper part of both lungs. The CT scan showed alveolar and round-glass opacities with a "mosaic-like" pattern. Bronchoalveolar lavage confirmed pulmonary hemorrhage. Renal biopsy was indicated because proteinuria revealed extracapillary glomerulonephritis. Laboratory tests showed a high level of serum antimyeloperoxidase-antineutrophil cytoplasmic antibody. We made a diagnosis of MPA. Cyclophosphamide and corticosteroid therapy was instituted and remission achieved. Through this case report, we discuss the diversity of the radio-clinical features of MPA.