Human pulmonary nocardiosis.

The involvement of Nocardia species in human pulmonary infections was investigated. Pulmonary nocardiosis mimics pulmonary tuberculosis in both clinical symptoms and radiological characteristics. In third world countries where diagnosis is based solely on such findings, anti-tuberculosis regimens may indicate chronic tuberculosis when in fact pulmonary nocardiosis should have been treated. Differential diagnosis is recommended for efficient health care and cost-effective drug use.