Nocardiosis in patients with systemic lupus erythematosus. The Singapore Lupus Study Group.

Nocardia, a gram positive variably acid-fast aerobic bacterium is an opportunistic pathogen in immunocompromised hosts. We present 5 cases of nocardiosis in patients with systemic lupus erythematosus. We emphasize the clinical features, radiologic findings, and antibiotic sensitivity. Lung involvement was the predominant manifestation; others include brain abscess, retinitis, thyroiditis, and diaphragmatic infiltration. We describe the first cases of pulmonary nocardiosis presenting as pneumothorax and the use of fine needle aspiration cytology in diagnosing nocardial thyroiditis.