Tuberculosis: Old and new disease

Abstract

M. tuberculosis is a part of the M. tuberculosis complex and is the causative agent of the infectious disease tuberculosis (TB) in humans. Lungs are the most frequently affected organ at about 90% of all the cases, and extrapulmonary localizations are less often and can affect any organ and tissue. Conventional diagnosis of tuberculosis includes: microscopy of ZiehlNeelsen-stained samples, cultivation of mycobacteria on solid Lowenstein medium, first-line antituberculosis (ATL) sensitivity test for M. tuberculosis. It is often a long long-lasting that lasts two to three months. In the last decades, methods for faster diagnosis of tuberculosis are of great importance and have found a place in practical work in equipped laboratories, and the results are obtained quickly, in a day or two. At the National Reference Laboratory, the Xpert MTB/RIF and GenoType MTBDRplus assays (Hain, Lifescience) are used for this purpose. Standard first-line therapy for the treatment of TB sensitive to antituberculosis drugs lasts 6 months and consists of four drugs: isoniazid, rifampicin, ethambutol and pyrazinamide. In the era of biological therapy, which significantly contributed to the successful treatment of many diseases and the extension of the lifespan, tuberculosis is still actual, due to the immunosuppressive effect of biological therapy, which affects the reactivation of latent infection and the development of active disease. A significantly high risk of TB occurs at the beginning of the administration of biological therapy, especially the first 6 to 12 months, and it is necessary to monitor the clinical course for 3-4 months. Compared to the general population, patients on anti-TNF therapy are 4 to 8 times more likely to develop active TB than those who are not receiving biological therapy. In most countries, screening and treatment of latent tuberculosis (LTBI) has been introduced before starting biological therapy, primarily with drugs from the TNF-alpha antagonists group, with the aim of reducing the incidence of active TB in these patients.