Multidrug and extensively drug-resistant tuberculosis in Lisbon and Vale do Tejo, Portugal, from 2008 to 2010

Tuberculosis (TB) was explicitly recognized as a major global public health problem in the early 1990s and, if it is to be eliminated, it is essential that every country organize control activities in line with its own epidemiological situation. Portugal still remains among the countries with intermediate incidence, with 2756 cases of TB diagnosed in 2009. The incidence of multidrug-resistant (MDR) TB has been decreasing, representing an average of 1.7% of the total number of TB cases, with about 25% of extensively drug-resistant (XDR) TB, and with more than two thirds residing in the region of Lisbon and Vale do Tejo (LVT). The aim of this study is to evaluate risk factors and treatment outcomes associated with MDR and XDR-TB in LVT during the time period of 2008-2010. In 50 (2.4%) out of 2093 culture-positive TB cases from patients diagnosed in the LVT region, Mycobacterium tuberculosis (MTB) isolates were identified as MDR-TB; 12 (24%) met the criteria for XDR-TB. It was noted that HIV-positive status and retreatment cases are still closely associated with drug-resistant TB. Although the WHO target of about 75% treatment success rates for MDR-TB was not yet achieved, extensive drug susceptibility testing and the availability of second- and third-line drugs under strictly supervised treatment conditions permitted relatively good treatment success rates in MDR and XDR-TB cases in Lisbon.