[Nocardiosis].

Nocardiasis is a usually pulmonary infection caused by Nocardia asteroides in most cases. It may present with signs of acute or chronic manifestations suggesting lung tuberculosis, mycosis or cancer. Its blood-borne dissemination from the primary pulmonary focus occurs preferentially in immunocompromised patients, which accounts for the ever increasing number of systemic nocardiasis observed nowadays. The infection predominantly affects the central nervous system and the subcutaneous tissue, but all organs may be involved. With sulphonamides, which are the first choice but non exclusive treatment, therapeutic success can be obtained. However, the systemic and neurological forms of nocardiasis have a poor prognosis which can be improved by a rapid diagnosis and an early treatment.