[MPO-ANCA related diffuse alveolar hemorrhage].

The purpose of this study was to elucidate the clinical features characterizing patients with myeloperoxidase specific-antineutrophil cytoplasmic antibody (MPO-ANCA) related diffuse alveolar hemorrhage (DAH). Seventeen MPO-ANCA-positive patients were evaluated. Nine patients (52.9%) had pulmonary involvement; of those, 6 (35.3%) had DAH, and 4 (23.5%) had interstitial pneumonia (1 patient had both pulmonary diseases). Three of the patients with DAH demonstrated only mildly bloody sputum. All patients with DAH had increased peripheral white blood cell counts, high titers of C-reactive protein and MPO-ANCA, and marked microscopic hematuria. DAH was diagnosed in all cases by fiberoptic bronchoscopy with bronchoalveolar lavage. All patients with DAH were treated with three pulses of methylprednisolone, and 5 were treated with cyclophosphamide. Three of the patients with DAH required mechanical ventilation for respiratory insufficiency, but 2 were relieved of that need by immunosuppressive therapy. In spite of intensive care, 1 patient died of respiratory failure and 2 died of complications related to therapy. The prognosis for patients with DAH is poor. We emphasize the importance of prompt and accurate diagnoses and aggressive care, including immunosuppressive therapy, mechanical ventilation, and hemodialysis. In addition, extra precautions should be taken against opportunistic infections such as Pneumocystis carinii pneumonia.