[Bacterial infections and immunosuppression].

Organ transplantation and the modern treatment of leukemia have created a new situation favouring bacterial infection under immunosuppressive drugs. Exceptionally, due to pathogenic bacteria, these infections are usually due to various germs normally considered as inoffensive saprophytes, which may thus reveal immune deficiency in the patient. This immune failure, which is very pronounced in treated leukemic patients and following transplantation, is on the contrary often localised at a precise level during common infections. Knowledge of these levels is thus essential for the clinician who, in all infected patients, should assess the state of the skin, mucosal and tissue and humoral defences whether specific or non-specific in the light of modern immunological data. Infection in the immunodepressed subject requires urget treatment. Antibiotics are not the only form of treatment, one should supervise, maintain and restore adequate immune levels. Furthermore, antibiotics alone, although they reduce the frequency, do not finally improve the mortality rate from gram-negative septicemia acquired in hospital.