Search

The Mycobacterium tuberculosis Beijing genotype raises major concern because of global spreading, hyper-virulence and association with multi-drug resistance (MDR). The aims of the study were to evaluate role of Beijing family in the epidemiological setting of Milan and to identify predictors associated with the spreading of this lineage. Overall 3830. TB cases were included. Beijing family accounted for 100 isolates (2.6%). Prevalence grew from 1.7% to 5.4% in the period 1996-2009. Foreign origin increased significantly the risk of having a Beijing strain: the greatest risk was observed among patients coming either from China [AOR = 57.7, 95%CI (26.3-126.8)] or from Former Soviet countries [AOR = 33.9, 95%CI (12.8-99.6)]. Also MDR was independently associated with Beijing family [AOR = 2.7, 95%CI (1.3-5.8)], whereas male gender and younger age only approximated the statistical significance [. p 0.051 and p 0.099, respectively].However, the percentage of cases attributable to MDR strains decreased over time, both in the Beijing group and in the non-Beijing group.97 isolates were grouped in 37 sub-lineages: MT11, MT33 were predominant. Beijing family is an emerging lineage in Milan. Origin from countries like China and Ukraine and MDR are significantly associated with Beijing. The broad range of the sub-lineages reflects the recent dynamics of the migration flows to our area. This scenario can prelude to a constant increase in the spreading of Beijing strains in the near future. © 2014 Elsevier B.V

Purpose: Recurrence of tuberculosis (TB) can be the consequence of relapse or exogenous reinfection. The study aimed to assess the factors associated with exogenous TB reinfection. Methods: Prospective cohort study based on the TB database, maintained at the Division of Infectious Diseases, Luigi Sacco Hospital (Milan, Italy). Time period: 1995–2010. Inclusion criteria: (1) ≥2 episodes of culture-confirmed TB; (2) cure of the first episode of TB; (3) availability of one Mycobacterium tuberculosis isolate for each episode. Genotyping of the M. tuberculosis strains to differentiate relapse and exogenous reinfection. Logistic regression analysis was used to assess the influence of risk factors on exogenous reinfections. Result: Of the 4682 patients with TB, 83 were included. Of these, exogenous reinfection was diagnosed in 19 (23 %). It was independently associated with absence of multidrug resistance at the first episode [0, 10 (0.01–0.95), p = 0.045] and with prolonged interval between the first TB episode and its recurrence [7.38 (1.92–28.32) p = 0.004]. However, TB relapses occurred until 4 years after the first episode. The risk associated with being foreign born, extrapulmonary site of TB, and HIV infection was not statistically significant. In the relapse and re-infection cohort, one-third of the patients showed a worsened drug resistance profile during the recurrent TB episode. Conclusions: Exogenous TB reinfections have been documented in low endemic areas, such as Italy. A causal association with HIV infection could not be confirmed. Relapses and exogenous reinfections shared an augmented risk of multidrug resistance development, frequently requiring the use of second-line anti-TB regimens.

SETTING: Luigi Sacco Hospital, Milan, Italy, 1 January 2000-31 December 2010. OBJECTIVES: To develop a predictive score for identifying human immunodeficiency virus (HIV) infected patients with pulmonary tuberculosis (PTB). DESIGN: Retrospective study based on the medical charts of HIV-infected patients admitted consecutively on presumption of PTB. Patients with culture-positive TB were included in the TB group. Culture-negative subjects formed the non-TB group. Risk factors for PTB were identified and a predictive model was developed. The diagnostic test accuracy of the derived score and that of previously developed scores were analysed. RESULTS: A total of 65 patients were included in the TB group and 505 subjects in the non-TB group. An eight-variable model (age, origin, alcohol use, respiratory rate, weight loss, haemoglobin, white blood cell count, typical chest X-ray) was derived. When compared with the different scores, this model showed the greatest area under the receiver operating characteristic curve (0.880). This score was the only one to present a negative likelihood ratio of