PULMONARY CAPILLARITIS AND DIFFUSE ALVEOLAR HEMORRHAGE - A PRIMARY MANIFESTATION OF POLYMYOSITIS

Polymyositis is of ten complicated by either usual interstitial pneumo nitis, diffuse alveolar damage, cellular interstitial pneumonitis, or bronchiolitis obliterans-organizing pneumonia. Pulmonary capillaritis, a distinct interstitial reaction associated with diffuse alveolar hem orrhage, occurs with the systemic vasculitides and some collagen vascu lar diseases. It has not been described in patients with polymyositis. We describe two patients who developed a relatively acute onset of po lymyositis based on the appearance of a severe proximal myopathy, elev ated serum creatine phosphokinase levels, compatible electromyographic abnormalities, inflammatory muscle biopsies, and in one case, the pre sence of serum anti-Jo-1 antibodies. Concomitant with their muscle dis ease, they developed respiratory failure that proved to be pulmonary c apillaritis with varying degrees of diffuse alveolar hemorrhage as wel l as bronchiolitis obliterans-organizing pneumonia. Although those rea ctions are reported to occur with other collagen vascular diseases, th ese two cases are the first reports of pulmonary capillaritis and diff use alveolar hemorrhage complicating polymyositis.