Microscopic polyangiitis associated with pleuropericarditis, pulmonary embolism and pulmonary hemorrhage as a complication of silicosis.

Silica (silicon dioxide) occupational exposure has been linked to both pulmonary and extra-pulmonary toxicity. Silicosis is the major pulmonary toxicity, which has also been associated with the development of collagen-vascular disease and with anti-neutrophil cytoplasmic antibody (ANCA)-positive vasculitis, especially perinuclear anti-neutrophil cytoplasmic antibodies (P-ANCA). The most common pulmonary manifestations of microscopic polyangitis (MPA) are interstitial fibrosis and alveolar hemorrhage.