Pulmonary nocardiosis: Ct findings

Objective: To evaluate CT findings of pulmonary nocardiosis in immunocompromised patients. Materials and Methods: Five patients with bacteriologically confirmed pulmonary nocardiosis were evaluated. Four patients were receiving corticosteroids with or without other immunosuppressive drugs for lupus nephritis (two patients), idiopathic thrombocytopenic purpura (one patient), and renal transplantation (one patient), and one patient had long-standing diabetes. Nocardia asteroides was isolated from blood culture, bronchial washing, pleuropulmo- nary aspirates, or open lung biopsy. Plain chest radiography and CT were performed on all patients, and follow-up CT was performed on one patient. Results: On CT there were pleural effusion (four patients), air-space consolidation with internal low attenuation with or without cavities (four patients), multiple noncavitating pulmonary nodules and subpleural pulmonary nodules (three patients), and chest wall extension (three patients). Follow-up CT after treatment showed marked improvement of the pleural and pulmonary lesions. Conclusion: In the immunocompromised and chronically debilitated host, pulmonary nocardiosis should be included in differential diagnosis if chest CT shows consolidation with low attenuation areas with or without cavitation, multiple pulmonary nodules, pleural effusion, and chest wall extension.