A 70-year-old woman undergoing long-term treatment for systemic scleroderma and secondary Sjögren syndrome developed fever during tapering of steroids. Chest CT showed centrilobular granular shadow and ground glass opacities. The pathology of transbronchial lung biopsy and the findings of bronchoalveolar lavage fluid were consistent with hypersensitivity pneumonitis and positive for anti-Trichosporon asahii antibody. Because her symptoms and imaging findings improved after house cleaning, she was diagnosed with summertype hypersensitivity pneumonitis. When lung lesions are found in patients with collagen disease, it is necessary to distinguish various diseases. In particular, allergic diseases can be difficult to diagnose by steroid therapy. In order to make an accurate diagnosis, medical history and image interpretation should be performed carefully and histologically searched as much as possible.
Keywords: steroid; summer-type hypersensitivity pneumonitis; systemic sclerosis.