Pulmonary nocardiosis in human immunodeficiency virus infection: a tuberculosis mimic.

Patients with human immunodeficiency virus (HIV) infection are prone to develop pulmonary infections like nocardiosis. It is often misdiagnosed as pulmonary tuberculosis since the manifestations are similar. A twenty-seven years old male presented with fever, cough with expectoration and weight loss for two months. Chest radiograph showed opacity in the right mid zones. Sputum smears were negative for acid fast bacilli (AFB) and revealed gram positive branching filamentous organisms resembling Nocardia species. Subsequently, Nocardia was grown on sputum culture. HIV antibody was positive by ELISA test. He was treated with co-trimoxazole. If sputum is repeatedly tested negative for AFB in the setting of radiological suspicion of tuberculosis, testing for Nocardia species should be considered in the HIV-infected patients.