A Case of Diffuse Alveolar Hemorrhage Accompanied by Pneumococcal-positive Bronchial Casts

Background. Infectious diseases rarely cause diffuse alveolar hemorrhage (DAH). There have been no reports of DAH complicated by bloody bronchial casts and Streptococcus pneumoniae. Case. A 33-year-old man was referred to our hospital with bloody sputum. Computed tomography (CT) showed diffuse ground glass opacity and thickened interlobular septa in both lungs. The CT findings worsened over a week, with findings suggestive of occlusion of the left lower lobe bronchi. Bronchoscopy showed bloody bronchial casts occluding the left lower lobe bronchi. The bloody bronchial casts were removed using a bronchoscope. A histopathological analysis of the bronchial alveolar lavage fluid (BALF) and lung biopsy specimen confirmed DAH. A pathological study of the lung specimen showed a normal alveolar structure. Furthermore, S. pneumoniae was cultured from the bloody bronchial casts and BALF. The patient's symptoms and CT findings gradually improved after a bronchoscopic examination, without antibiotics or steroids. Conclusion. DAH can accompany bloody bronchial casts, and S. pneumoniae can be cultured from the casts and BALF. In such cases, removal of the bronchial casts can help prevent the development of subsequent pneumonia.