Hypersensitivity pneumonitis: bagassosis.

Pneumoconiosis from inorganic dusts is very common worldwide and has been studied by many experts in Taiwan. However, pneumoconiosis due to organic dusts, i.e. hypersensitivity pneumonitis, seems rather uncommon in Taiwan, and to our best knowledge there has been no related report so far. In this study, we shall report five cases of bagassosis. These five patients all were men, ranging in age from 29 to 52 years. One of them worked at a sugarcane factory, and the remaining four all worked at the paper mills. The exposure history to organic dusts ranged from 2 days to 15 years. Their chief complaints were cough, dyspnea, and fever. The chest roentgenographic manifestations in our patients could mainly be subdivided into three patterns; i.e. reticulonodular infiltrates (three cases), reticular infiltrates (one case), and miliary nodular infiltrates (one case). These lesions were located diffusely with predilection for both lower lung fields. Three patients received bronchoalveolar lavage (BAL), which revealed a predominantly lymphocytic population. Arterial blood gas determinations in room air showed hypoxemia in most of them, but none of them were hypercapnic. Pulmonary function testing typically showed a restrictive ventilatory pattern in all of our cases, and the most sensitive diffusion capacity of carbon monoxide (DLco) ranged from 43% to 78% of the normal value. All of our patients received corticosteroid therapy after establishment of the diagnosis and had rather satisfactory responses. In addition, we also present possible preventive measures in the field of industrial hygiene.