Méthodes diagnostiques de l'infection tuberculeuse en 2007: intradermoréaction à la tuberculine ou interféron-γ?

[Primary infection and pulmonary tuberculosis]

Tuberculosis is a major public health problem worldwide. Indeed, a third of the world population is infected with Mycobacterium tuberculosis and more than 8 million new cases of tuberculosis each year. Pulmonary tuberculosis is the most common location. Its diagnosis is difficult and often established with a delay causing a spread of infection. The diagnosis of tuberculosis infection is mainly based on immunological tests represented by the tuberculin skin test and detection of gamma interferon, while the diagnosis of pulmonary tuberculosis is suspected on epidemiological context, lasting general and respiratory symptoms, contrasting usually with normal lung examination, and a chest radiography showing suggestive lesions. The radioclinical feature may be atypical in patients with extreme ages and in case of immunodeficiency. Confirmation of tuberculosis is bacteriological. Conventional bacteriological methods remain the reference. Innovative tests using the technique of molecular biology have improved the diagnosis of tuberculosis in terms of sensitivity and especially speed. However, those techniques are of limited use.

Corticothérapie systémique et risque infectieux

PURPOSE

It was shown that corticosteroids alter the inflammatory and immune responses. Many publications report on serious infections occurring in patients receiving corticosteroids or presenting with Cushing's syndrome. This information is synthesized in this article.

CURRENT KNOWLEDGE AND KEY POINTS

The demonstration of the infectious risk associated with corticosteroids relies on observational data and on biological plausibility. However, this risk remains difficult to quantify, because of many confusing factors such as the patients' associated conditions and immunosuppressive treatments, and the highly variable dose and duration of the corticosteroid treatment. Taking into account the published data, the screening for a chronic infection seems licit among patients receiving a systemic corticosteroid treatment, in particular for those who will receive more than 10 mg of prednisone per day.

FUTURE PROSPECTS

Although no clinical trials of prevention of infections in corticosteroid treated patients has been published, a strategy aiming at minimizing the infectious risk of corticosteroid treated patients is proposed, based on the analysis of the literature presented in this article.

[Empiric antituberculous therapy in patients with unexplained exsudative pleural effusion. Is it valid in Senegal?]

AIM

Pleural biopsy and adenosine deaminase activity are not available at our center and the treatment begins without substantiation diagnosis in patients with tuberculous pleural effusion (PE).

METHODS

In order to evaluate the validity of an empiric antituberculous therapy in exsudative PE with high prevalence of lymphocytes, we conducted a retrospective study during 1 year. Patient was enrolled if no signs of tuberculous infection, pneumonia or cancer were present.

RESULTS

During 1 year, 38 patients were enrolled (23 males, mean age=36 years). PE was major (> 2/3 of the lung) in 14 cases, moderate (between 1/3 and 2/3) In 18 cases and minor (<1/3) in 6 cases. Tuberculous contagion was observed in 10 patients. Tuberculinic test was positive in all patients (12-24 mm). Clinical and radiological cure was obtained in 37 cases, except 1 patient who died from acute heart failure. No recurrence of PE was observed after 1 year follow-up.

CONCLUSION

In our endemic areas, empiric antituberculous treatment seems to be an effective strategy in patients with exsudative PE.