[Manifestations, diagnosis and treatment of non-tuberculous mycobacterial infections in patients with HIV infection].

The most frequent bacterial infections in patients infected with HIV and suffering from AIDS are non-tuberculous mycobacterial infections. Their incidence is increasing all the more as the survival of profoundly immunocompromised patients is prolonged. There are unknown factors as regards the precise origin of these infections and as to the exact epidemiology of atypical mycobacteria. It is known that 95 per cent of atypical mycobacterial infections are due to M. avium. If the pathophysiology of the infection (involving the intervention of cytokines and also factors in relation to the virulence of the germ) is imperfectly understood, the atypical mycobacteria are an independent cause of mortality in advanced stages of the disease. The clinical picture is that of a low grade fever with weight loss and a deterioration in the general physical state. There are subtle physical signs such as a fall in the functional capacity accompanied by weight loss and an unexplained anaemia these should also suggest a diagnosis. More rarely the infection will be localised. The clinical diagnosis will be confirmed by bacteriology which has been aided by recent progress in molecular biology. With the arrival of the newer macrolides it has been shown that treatment prolongs survival in a significant manner. Current recommendations consist of a treatment with a combined regime including a minimum of Clarithyromycin and Ethambutol. The place for polychemotherapy remains to be determined in particular the role for Rifabutine and Amikacine. Immunomodulation by interferon-gamma or GCSF are also under review. The duration of treatment and the necessity of long term suppressive treatment is the object of randomised studies. Prophylaxis is currently recommended for patients with CD4 < 75/mm3. The role of Rifabutine and the new macrolides remains to be determined. Finally, in a large European study the objective is to compare prophylaxis to systematic bacteriological surveillance both as regards efficacy, tolerance, and in terms of pharmaco-economics.