A 59-year-old woman suffering from dry cough and dyspnea was admitted to our hospital. She had undergone concurrent chemo-radiotherapy five months earlier. Chest computed tomography revealed bilateral ground-glass opacities extending outside the irradiated lung field. Her eosinophil numbers were increased in both the peripheral blood and the bronchoalveolar lavage fluid; therefore, she was diagnosed with radiation pneumonitis accompanied by eosinophilic alveolitis. Steroid therapy promptly improved the pneumonitis. Radiation pneumonitis accompanied by eosinophilic alveolitis extending outside the irradiated field is rare. Bronchoalveolar lavage is useful for a diagnosis, and steroid therapy is effective for treatment.
Keywords: bronchoalveolar lavage; eosinophilia; lung cancer; radiation pneumonitis; steroid.