Treatment outcomes among multidrug-resistant tuberculosis (MDR-TB) cases at a referral hospital of infectious diseases in Italy

Background: MDR-TB is emerging as a major challenge for tuberculosis control programs.In Italy the proportion of MDR-TB reported during 2013 was 3.3%; unfortunately, treatment outcomes in MDR-TB patients are poorly documented. Aim: To evaluate the outcomes of MDR-TB patients treated at the National Institute of Infectious Disease (INMI), a referral hospital for Infectious Diseases in Italy. Methods: 74 MDR-TB patients diagnosed between 2008 and 2015 were consecutively enrolled in an observational retrospective cohort study. All patients were treated according WHO guidelines. Results: The patients (median age 35.8 yr) were mainly male (63.5%) and foreign born (87.2%). Among 74 patients, 2 were extensively drug-resistant (XDR) cases, 2 patients were HIV-coinfected,and 45 (61.0%) were newly diagnosed. Fifty-eight (78.4%) cases were pulmonary sputum smear-positive. 51% of patients were transferred in from units of other regions of central and southern Italy. Among 57 patients who completed treatment in the study period, 68.4 % achieved treatment success, 22.8% were lost to follow up, 3% were transferred out and 1.8% died. Conclusion: Monitoring the treatment outcome of MDR-TB is essential to evaluate the effectiveness of interventions and to identify potential barriers for TB control. In our cohort MDR-TB is mainly related to the immigration of patients from countries with a high TB prevalence with a high proportion of new cases. Data show that, in a referral center for the treatment of MDR-TB, success rates close to the target defined by WHO can be achieved, even if actions are required to reduce the high proportion of patients lost to follow-up.