Assessment of linezolid efficacy, safety and tolerability in the treatment of tuberculosis: A retrospective case review.

Linezolid is a potentially effective drug for the treatment of patients with drug-resistant tuberculosis. Among 13 patients treated for tuberculosis with linezolid in the present study, nine had treatment success and four remain on treatment. Adverse effects occurred in 11 (85%) patients, of whom three discontinued treatment because of adverse effects. The present study adds to the growing evidence supporting the efficacy of linezolid for tuberculosis, although treatment remains complicated by adverse effects.

Le linézolide est un médicament qui peut être efficace dans le traitement de patients atteints d'une tuberculose résistant aux médicaments. Dans la présente étude, chez 13 patients traités au linézolide contre la tuberculose, neuf ont vu leur traitement réussir et quatre sont toujours en traitement. Des effets indésirables se sont manifestés chez 11 (85 %) patients, dont trois ont arrêté le traitement pour cette raison. La présente étude s'ajoute aux données croissantes étayant l'efficacité du linézolide pour soigner la tuberculose, même si le traitement demeure compliqué par des effets indésirables.

Factors associated with reduced antituberculous serum drug concentrations in patients with HIV-TB coinfection.

We describe correlates of reduced antituberculous serum drug concentrations (SDCs) in HIV-infected patients receiving treatment for active tuberculosis (TB). Cross-sectional analysis of individuals diagnosed with HIV and active TB in Northern Alberta, Canada, was performed. Of the 30 HIV-TB cases, 27 underwent measurement of SDCs. Rates of low SDCs were 9 of 26 (34%) for isoniazid (INH) and 16 of 25 (64%) for rifamycins. Increased weight and elevated body mass index (BMI) correlated with low SDCs for rifampin (P < .05) and increased weight also correlated with reduced SDCs for INH (P < .05). This suggests that conventional antituberculous dosing may be too low and consideration should be given to increase the maximum initial weight-based doses in HIV-infected patients.

A shelter-associated tuberculosis outbreak: a novel strain introduced through foreign-born populations.

OBJECTIVE: An outbreak of tuberculosis (TB) in a large urban apartment building and three homeless shelters within a one-block radius in Edmonton, Alberta occurred between 2008 and 2009. The purpose of this report is to describe the transmission dynamics of this multiethnic, multicentre inner-city TB outbreak. METHODS: A retrospective chart review was conducted through the Integrated Public Health Information Systems (iPHIS) to extract demographic, clinical and treatment data as well as data for contacts for all 19 cases involved in the outbreak. TB isolates were genotyped using molecular IS6110 restriction fragment-length polymorphism (RFLP). Categorical variables were compared using Fisher's exact test and continuous variables were analyzed using the Kruskal Wallis test. RESULTS: Two groups were identified through genotyping. One group consisted of 9 cases with a newly identified TB genotype circulating in Alberta. All of the cases in this group were among males and two thirds were among individuals from northeast Africa, with subsequent transmission into Canadian-born populations through exposure during shelter stays. The second group (n=3) identified were infected by a previously circulating strain of TB in Alberta and consisted of Canadian-born Aboriginal people. CONCLUSION: This study demonstrates the transmission of a novel TB strain from foreign-born populations to Canadian-born populations through location-based settings serving vulnerable populations. This study highlights the changing demographic and emerging health concerns for under-housed populations in Canada.

Sustained intra- and inter-jurisdictional transmission of tuberculosis within a mobile, multi-ethnic social network: lessons for tuberculosis elimination.

BACKGROUND: A context-specific, spatial-temporal understanding of a chain of tuberculosis (TB) transmission can inform TB elimination strategy. METHODS: Clinical, public health and molecular epidemiologic data were used to: 1) identify and describe a complex cluster of TB cases in Alberta, 2) elucidate transmission sequences, and 3) assess case-patient mobility. Socio-economic indicators in loci of transmission and the province at large were described. Factors seen to be fostering or hampering TB elimination were identified. RESULTS: Over a 15-year period, 18 TB cases in Alberta and multiple cases in the Northwest Territories were determined to be due to the same strain. One patient was diagnosed at death; all others completed directly-observed therapy (DOT). Case-level analysis revealed that patients were highly mobile with transmission of the strain over 26,569 km2, an average of 2.8 different places of residence per patient during treatment, and contacts of sputum smear-positive cases spanning 9 of 17 regional health authorities. The majority of the contacts (57%) were attached to a single infectious case living in a homeless shelter. The three loci of transmission in Alberta were separated geographically but similar in terms of median incomes, rates of unemployment, levels of post-secondary education, and rates of population mobility (p < 0.0001). CONCLUSION: Upon review of the experience, central oversight, intra- and inter-jurisdictional coordination and DOT were seen as fostering, and the absence of 'real-time' DNA fingerprinting, social network analysis, engineering controls in shelters and better determinants of health in loci of transmission were seen as hampering TB elimination.