Tuberculosis prophylaxis in the immunosuppressed subject.

Immunosuppressed patients have an increased risk of developing active tuberculosis, either br reactivation of an old infection, or by horizontal acquisition during a contact with a contageous tuberculous patient. The diagnosis or tuberculosis requires a clinical examination and the realization of a PPD skin test and a pulmonary radiograph. Symptomatic tuberculosis is a contra-indication to chemoprophylaxis and requires a full curative treatment. The decision to undertake chemoprophylaxis should be individual, When indicated, it relies classically on a 6-month regimen of isoniazid. Short term chemoprophylactic regimens, such as rifampicin-isoniazid during 3 months or rifampicin-pyrazinamide during 2 months, have shown some efficacy. The interaction of rifampicin with corticosteroids or ciclosporin often impedes the use of this antibiotic. Apart from HIV infection, no clinical study of chemoprophylaxis is available in immunosuppressed patients.