Latent tuberculosis infection (LTBI) is characterised by the presence of immune responses to previously acquired Mycobacterium tuberculosis infection without clinical evidence of active tuberculosis (TB). Here we report evidence based guidelines from the World Health Organization for a public health approach to the management of LTBI in high risk individuals in countries with high or middle upper income and TB incidence of <100 per 100 000 per year. The guidelines strongly recommend systematic testing and treatment of LTBI in people living with HIV, adult and child contacts of pulmonary TB cases, patients initiating anti-tumour necrosis factor treatment, patients receiving dialysis, patients preparing for organ or haematological transplantation, and patients with silicosis. In prisoners, healthcare workers, immigrants from high TB burden countries, homeless persons and illicit drug users, systematic testing and treatment of LTBI is conditionally recommended, according to TB epidemiology and resource availability. Either commercial interferon gamma release assays or Mantoux tuberculin skin testing could be used to test for LTBI. Chest radiography should be performed before LTBI treatment to rule out active TB disease. Recommended treatment regimens for LTBI include: 6 or 9 month isoniazid; 12 week rifapentine plus isoniazid; 3–4 month isoniazid plus rifampicin; or 3–4 month rifampicin alone.

Background-Tuberculosis is a common complication and leading cause of death in HIV infection. Antiretroviral therapy (ART) lowers the risk of tuberculosis, but may not be sufficient to control HIV-related tuberculosis. Isoniazid preventive therapy (IPT) reduces tuberculosis incidence significantly, but is not widely used.

New scientific articles about tuberculosis (TB) are published daily worldwide. However, it is difficult for health care workers, overloaded with work, to stay abreast of the latest research findings and to discern which information can and should be used in their daily practice on assisting TB patients. The purpose of the III Brazilian Thoracic Association (BTA) Guidelines on TB is to critically review the most recent national and international scientific information on TB, presenting an updated text with the most current and useful tools against TB to health care workers in our country. The III BTA Guidelines on TB have been developed by the BTA Committee on TB and the TB Work Group, based on the text of the II BTA Guidelines on TB (2004). We reviewed the following databases: LILACS (SciELO) and PubMed (Medline). The level of evidence of the cited articles was determined, and 24 recommendations on TB have been evaluated, discussed by all of the members of the BTA Committee on TB and of the TB Work Group, and highlighted. The first version of the present Guidelines was posted on the BTA website and was available for public consultation for three weeks. Comments and critiques were evaluated. The level of scientific evidence of each reference was evaluated before its acceptance for use in the final text.Keywords: Tuberculosis; Mycobacterium infections; Diagnosis; Tuberculosis, multidrug-resistant. ResumoDiariamente novos artigos científicos sobre tuberculose (TB) são publicados em todo mundo. No entanto, é difícil para o profissional sobrecarregado na rotina de trabalho acompanhar a literatura e discernir o que pode e deve ser aplicado na prática diária juntos aos pacientes com TB. A proposta das "III Diretrizes para TB da Sociedade Brasileira de Pneumologia e Tisiologia (SBPT)" é revisar de forma crítica o que existe de mais recente na literatura científica nacional e internacional sobre TB e apresentar aos profissionais da área de saúde as ferramentas mais atuais e úteis para o enfrentamento da TB no nosso país. As atuais "III Diretrizes para TB da SBPT" foram desenvolvidas pela Comissão de TB da SBPT e pelo Grupo de Trabalho para TB a partir do texto das "II Diretrizes para TB da SBPT" (2004). As bases de dados consultadas foram LILACS (SciELO) e PubMed (Medline). Os artigos citados foram avaliados para determinação do nível de evidência científica, e 24 recomendações sobre TB foram avaliadas, discutidas por todo grupo e colocadas em destaque. A primeira versão das "III Diretrizes para TB da SBPT" foi colocada no website da SBPT para consulta pública durante três semanas, e as sugestões, críticas e o nível de evidência da referência científica que as embasavam foram avaliados e discutidos antes de serem incorporadas ou não ao texto final.Descritores: Tuberculose; Infecções por Mycobacterium; Diagnóstico; Tuberculose resistente a múltiplos medicamentos.

Betina Durovni and colleagues evaluated whether implementation of Xpert MTB/RIF increased the notification rate of laboratory-confirmed pulmonary tuberculosis and reduced the time to tuberculosis treatment initiation in 14 Brazilian primary care laboratories. Please see later in the article for the Editors' Summary

Summary Background Preventive therapy for tuberculosis among HIV-infected patients is effective but has not been widely implemented in moderate/high-burden settings. Objectives To determine the impact of widespread use of isoniazid preventive therapy on rates of tuberculosis and death in HIV-infected individuals in Brazil. Design Stepped wedge, cluster randomized trial Participants Patients actively enrolled in 29 HIV clinics in Rio de Janeiro, Brazil Control period Standard of care Intervention period Staff training in tuberculosis screening, performance of tuberculin skin tests and use of isoniazid preventive therapy. Randomization Clinics were randomly allocated a date to begin the intervention period with two clinics beginning the intervention every 2 months starting September 1 2005. Main outcome measures Tuberculosis incidence alone or combined with death in the control versus intervention periods through August 31 2009. Results Among 17,413 patients in the THRio cohort, 12,816 were eligible for the intervention. Overall, there were 475 tuberculosis cases and 838 deaths. The intervention increased the rate of patients receiving skin tests from 19/100 person-years to 59/100 person-years, and from 36/100 person-years to 144/100 person-years for those eligible for isoniazid preventive therapy. In the control period, 221 tuberculosis cases were diagnosed (1·31/100 person-years) compared to 254 (1·10/100 person-years) in the intervention (unadjusted hazard ratio (HR)=0·87;95%CI:0·69–1·10). Rates of tuberculosis incidence or death were 3·64 and 3·04/100 person-years, respectively (HR=0·76; 95%CI:0·66–0·87). When adjusted for age, sex, entry CD4 count and use of antiretroviral therapy, the HR for tuberculosis was 0·73 (95%CI:0·54–0·99) and for tuberculosis or death was 0·69 (95%CI:0·57–0·83). Among 12,196 patients remaining in care (secondary analyses, 399 tuberculosis cases and 656 deaths), the adjusted HR of tuberculosis alone and combined with death were 0·42 (95%CI:0·29–0·60) and 0·45 (95%CI:0·35–0·56), respectively, Conclusions Operational training aimed at increasing tuberculosis screening, provision of tuberculin skin tests and use of isoniazid preventive therapy in Brazilian HIV clinics significantly reduced incident tuberculosis and death. Thus, scale-up of preventive therapy for HIV-infected patients in moderate tuberculosis incident settings is achievable and should be strongly considered in Brazil and elsewhere. Trial registration This trial is registered at clinicaltrials.gov (NCT00107887) Funding Bill & Melinda Gates Foundation; National Institutes of Health

The billions of people with latent tuberculosis infection serve as the seedbeds for future cases of active tuberculosis. Virtually all episodes of tuberculosis disease are preceded by a period of asymptomatic Mycobacterium tuberculosis infection; therefore, identifying infected individuals most likely to progress to disease and treating such subclinical infections to prevent future disease provides a critical opportunity to interrupt tuberculosis transmission and reduce the global burden of tuberculosis disease. Programs focusing on single strategies rather than comprehensive programs that deliver an integrated arsenal for tuberculosis control may continue to struggle. Tuberculosis preventive therapy is a poorly utilized tool that is essential for controlling the reservoirs of disease that drive the current epidemic. Comprehensive control strategies that combine preventive therapy for the most high-risk populations and communities with improved case-finding and treatment, control of transmission and health systems strengthening could ultimately lead to worldwide tuberculosis elimination. This paper outlines challenges to implementation of preventive therapy and provides pragmatic suggestions for overcoming them. It further advocates for tuberculosis preventive therapy as the core of a renewed global focus to implement a comprehensive epidemic control strategy that would reduce new tuberculosis cases to elimination targets. This strategy would be underpinned by accelerated research to further understand the biology of subclinical tuberculosis infections, develop novel diagnostics, and drug regimens specifically for subclinical tuberculosis infection, strengthen health systems, community engagement, and enhance sustainable large scale implementation of preventive therapy programs.

Objective The TB/HIV in Rio (THRio) study was launched in September 2005 to assess the impact of integrated tuberculosis (TB) and HIV treatment strategies in 29 HIV clinics in Rio de Janeiro, Brazil. Design THRio is a cluster-randomized trial (CRT) to determine whether routine screening for and treatment of latent TB in HIV clinic patients with access to antiretroviral therapy will reduce TB incidence at the clinic level. THRio is part of the Consortium to Respond Effectively to AIDS/TB Epidemic that is implementing research studies to assess the impact of bold, new public health paradigms for controlling the AIDS/TB epidemic. Methods Twenty-nine public primary HIV clinics were randomly assigned a date to begin implementing TB screening procedures and provision of isoniazid preventive therapy (IPT) for TB/HIV coinfected patients. Final analysis of the CRT is expected in 2011. Results Starting at date of tuberculin skin test (TST)/IPT implementation at each clinic through August 2010, 1670 HIV-infected patients initiated IPT, of which 215 are still receiving treatment. Of the remaining 1455 patients, 1230 (85%) completed therapy and only 20 (1.2%) patients initiating IPT reported adverse reactions leading to discontinuation of therapy. IPT completion was higher among HIV-infected patients receiving HAART (87%) than those not yet receiving HAART (79%, P < 0.01). Times to TST and IPT have markedly decreased postintervention, but remain considerably long. The richness of the THRio database has resulted in several analyses of this expansive cohort of HIV-infected patients that are reviewed here. Conclusions The national implementation of TST and IPT for HIV-positive patients in Brazil has been invigorated partly due to THRio’s baseline results. Expanded use of IPT in HIV patients in Rio de Janeiro is achievable with high adherence and low adverse events, although this effort requires a package of activities including training, advocacy and reorganization of services.

Studies with cluster-randomized order of intervention introduction can provide useful information on intervention effects. Their design and analysis are more complicated than for individually randomized parallel design trials. The methods we describe represent practical approaches to the challenges raised in the course of designing this study.