[Etanercept and infection - latent tuberculosis].

Drugs that block the tumor necrosis factor alpha (TNFalpha) increase the risk of reactivation of latent tuberculosis infection (LTI). The risk is greater with monoclonal antibodies than with etanercept. In order to reduce this risk, screening of latent tuberculosis infection should be performed prior to the initiation of the treatment. Screening includes a complete clinical history, physical examination, tuberculin test, in vitro detection of interferon-gamma (INF-gamma) production and a chest x-ray. The limitations of the different tests should be taken into consideration by the physician. After the diagnosis of latent tuberculosis infection, the patient must receive treatment with isoniacide for 9 months. In spite of screening and adequate treatment of latent tuberculosis treatment, the patients receiving treatment with anti-TNFalpha drugs may develop active tuberculosis. Thus, the patient should undergo clinical follow-up to detect signs of active tuberculosis with atypical and disseminated pictures.