Haileyesus Getahun

WHO guidelines for the programmatic management of drug-resistant tuberculosis: 2011 update

The production of guidelines for the management of drug-resistant tuberculosis (TB) fits the mandate of the World Health Organization (WHO) to support countries in the reinforcement of patient care. WHO commissioned external reviews to summarise evidence on priority questions regarding case-finding, treatment regimens for multidrug-resistant TB (MDR-TB), monitoring the response to MDR-TB treatment, and models of care. A multidisciplinary expert panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to develop recommendations. The recommendations support the wider use of rapid drug susceptibility testing for isoniazid and rifampicin or rifampicin alone using molecular techniques. Monitoring by sputum culture is important for early detection of failure during treatment. Regimens lasting ≥20 months and containing pyrazinamide, a fluoroquinolone, a second-line injectable drug, ethionamide (or prothionamide), and either cycloserine or p-aminosalicylic acid are recommended. The guidelines promote the early use of antiretroviral agents for TB patients with HIV on second-line drug regimens. Systems that primarily employ ambulatory models of care are recommended over others based mainly on hospitalisation. Scientific and medical associations should promote the recommendations among practitioners and public health decision makers involved in MDR-TB care. Controlled trials are needed to improve the quality of existing evidence, particularly on the optimal composition and duration of MDR-TB treatment regimens.

Diagnosis of smear-negative pulmonary tuberculosis in people with HIV infection or AIDS in resource-constrained settings: informing urgent policy changes

The HIV epidemic has led to large increases in the frequency of smear-negative pulmonary tuberculosis, which has poor treatment outcomes and excessive early mortality compared with smear-positive disease. We used a combination of systematic review, document analysis, and global expert opinion to review the extent of this problem. We also looked at policies of national tuberculosis control programmes for the diagnosis of smear-negative pulmonary tuberculosis to assess their coverage, identify the diagnostic difficulties, and find ways to improve the diagnosis of this type of tuberculosis, with a focus on resource-constrained settings with high HIV infection rates. We propose that the internationally recommended algorithm for the diagnosis of smear-negative pulmonary tuberculosis should be revised to include HIV status, severity of AIDS and tuberculosis, and early use of chest radiography in the decision tree. Increased use of promising methods of diagnosis such as sputum liquefaction and concentration and increased availability of fluorescence microscopy should be explored and encouraged. Culturing of sputum in resource-constrained settings with high HIV infection rates should also be encouraged, existing facilities should be made full use of and upgraded, and effective quality-assurance systems should be used. Innovative ways to address human resources issues involved in addressing the diagnostic difficulties are also needed. The development of rapid, simple, and accurate tuberculosis diagnostic tools with applicability at point of care and remote location is essential. To achieve these goals, greater political commitment, scientific interest, and investment are needed.

HIV Infection—Associated Tuberculosis: The Epidemiology and the Response

Of the 33.2 million persons infected with human immunodeficiency virus (HIV), one-third are estimated to also be infected with Mycobacterium tuberculosis. In 2008, there were an estimated 1.4 million new cases of tuberculosis (TB) among persons with HIV infection, and TB accounted for 26% of AIDS-related deaths. The relative risk of TB among HIV-infected persons, compared with that among HIV-uninfected persons, ranges from 20- and 37-fold, depending on the state of the HIV epidemic. In 2008, 1.4 million patients with TB were tested globally for HIV, and 81 countries tested more than half of their patients with TB for HIV. Only 4% of all persons infected with HIV were screened for TB in the same year. Decentralization of HIV treatment services and strengthening of its integration with TB services are essential. Use of the highly decentralized TB services as an entry point to rapidly expand access to antiretroviral therapy and methods for prevention of HIV infection must be pursued aggressively.

Towards tuberculosis elimination: an action framework for low-incidence countries

This paper describes an action framework for countries with low tuberculosis (TB) incidence (<100 TB cases per million population) that are striving for TB elimination. The framework sets out priority interventions required for these countries to progress first towards “pre-elimination” (<10 cases per million) and eventually the elimination of TB as a public health problem (less than one case per million). TB epidemiology in most low-incidence countries is characterised by a low rate of transmission in the general population, occasional outbreaks, a majority of TB cases generated from progression of latent TB infection (LTBI) rather than local transmission, concentration to certain vulnerable and hard-to-reach risk groups, and challenges posed by cross-border migration. Common health system challenges are that political commitment, funding, clinical expertise and general awareness of TB diminishes as TB incidence falls. The framework presents a tailored response to these challenges, grouped into eight priority action areas: 1) ensure political commitment, funding and stewardship for planning and essential services; 2) address the most vulnerable and hard-to-reach groups; 3) address special needs of migrants and cross-border issues; 4) undertake screening for active TB and LTBI in TB contacts and selected high-risk groups, and provide appropriate treatment; 5) optimise the prevention and care of drug-resistant TB; 6) ensure continued surveillance, programme monitoring and evaluation and case-based data management; 7) invest in research and new tools; and 8) support global TB prevention, care and control. The overall approach needs to be multisectorial, focusing on equitable access to high-quality diagnosis and care, and on addressing the social determinants of TB. Because of increasing globalisation and population mobility, the response needs to have both national and global dimensions. Action framework for countries with low tuberculosis incidence: a coherent approach for eliminating tuberculosis http://ow.ly/H03ZZ

Scaling up interventions to achieve global tuberculosis control: progress and new developments

Tuberculosis is still one of the most important causes of death worldwide. The 2010 Lancet tuberculosis series provided a comprehensive overview of global control efforts and challenges. In this update we review recent progress. With improved control efforts, the world and most regions are on track to achieve the Millennium Development Goal of decreasing tuberculosis incidence by 2015, and the Stop TB Partnership target of halving 1990 mortality rates by 2015; the exception is Africa. Despite these advances, full scale-up of tuberculosis and HIV collaborative activities remains challenging and emerging drug-resistant tuberculosis is a major threat. Recognition of the effect that non-communicable diseases--such as smoking-related lung disease, diet-related diabetes mellitus, and alcohol and drug misuse--have on individual vulnerability, as well as the contribution of poor living conditions to community vulnerability, shows the need for multidisciplinary approaches. Several new diagnostic tests are being introduced in endemic countries and for the first time in 40 years a coordinated portfolio of promising new tuberculosis drugs exists. However, none of these advances offer easy solutions. Achievement of international tuberculosis control targets and maintenance of these gains needs optimum national health policies and services, with ongoing investment into new approaches and strategies. Despite growing funding in recent years, a serious shortfall persists. International and national financial uncertainty places gains at serious risk. Perseverance and renewed commitment are needed to achieve global control of tuberculosis, and ultimately, its elimination.

Development of a standardized screening rule for tuberculosis in people living with HIV in resource-constrained settings: individual participant data meta-analysis of observational studies.

Haileyesus Getahun and colleagues report the development of a simple, standardized tuberculosis (TB) screening rule for resource-constrained settings, to identify people living with HIV who need further investigation for TB disease.

WHO's new end TB strategy.

On May 19, 2014, the 67th World Health Assembly (WHA) adopted WHO’s “Global strategy and targets for tuberculosis prevention, care and control after 2015”. This post-2015 global tuberculosis strategy, labelled the End TB Strategy, was shaped during the past 2 years. A wide range of stakeholders—from ministries of health and national tuberculosis programmes to technical and scientifi c institutions, fi nancial and development partners, civil society and health activists, non-governmental organisations, and the private sector—contributed to its development. The strategy has a vision of making the world free of tuberculosis, with zero deaths, disease, and suff ering due to the disease (see appendix p 1 for summary of the End TB Strategy). In 2013, 9 million people fell ill with tuberculosis and 1·5 million died; about a quarter of them were HIV positive. Poor and deprived groups also bore the brunt of the enormous socioeconomic burden imposed by the disease and deaths. Concerned by this persistent human suff ering due to tuberculosis, but encouraged by the progress achieved during the past two decades and recognising the need to mount a multisectoral response to eff ectively address the problem, the health ministers at the WHA approved WHO’s proposal to push the limit of ambition to “end the global tuberculosis epidemic” by 2035, marked by well defi ned milestones and targets set along the way. Ending the tuberculosis epidemic implies bringing the levels of tuberculosis in the whole world down to converge with those already attained by many rich countries: fewer than ten new tuberculosis cases occurring per 100 000 population per year amounting to 90% reduction in tuberculosis incidence and tuberculosis deaths reduced by 95%. The rich countries achieved remarkable reductions in the tuberculosis burden not only by delivering adequate tuberculosis services, but also by pursuing universal access to health care and social protection while rapidly improving nutrition and economic conditions. Ending the tuberculosis epidemic in high-incidence countries needs a similar approach that guarantees access to high-quality tuberculosis care and prevention to all while simul taneously addressing the social determinants of tuberculosis. To this eff ect, elimination of catastrophic costs that tuberculosis-aff ected families face is an important milestone to be achieved under the End TB Strategy well within the next decade. Importantly, though, achievement of universal access to currently available methods of tuberculosis care and prevention will not be enough to end the epidemic within two decades. Global investments and eff orts are also essential to develop improved methods to diagnose, treat, and prevent tuberculosis. Equal emphasis on achievement of universal access to tuberculosis care and prevention, addressing of weaknesses in health systems and social determinants of tuberculosis, and pursuing of research and innovation for improved approaches and strategies constitute the core of the End TB Strategy. The achievements of the past two decades provide the basis for further progress. The DOTS (directly observed treatment, short-course) strategy of 1995 expanded access to high-quality tuberculosis care. The Stop TB Strategy of 2006 widened its scope to address management of all forms of tuberculosis including HIV-associated and drug-resistant tuberculosis, through engagement of communities, involvement of all care providers, strengthening of health systems, and fostering of research. Subsequently, the tuberculosis-related Millennium Development Goal to “halt and begin to reverse the incidence of tuberculosis” was achieved; 37 million lives were saved between 2000 and 2013; and a new rapid molecular test to simultaneously diagnose tuberculosis and rifampicin resistance was developed and two novel drugs were introduced. These achievements notwithstanding, the enormity of the task ahead cannot be overemphasised. Overall, the current 2% annual reduction in the global tuberculosis incidence is too slow to achieve an end to the epidemic in the foreseeable future. Tuberculosis remains a top infectious killer of men and women. A third of estimated incident tuberculosis cases go un-notifi ed or undiagnosed and close to half a million multidrug-resistant cases emerge each year. HIV-associated tuberculosis aff ects more than a million people a year. An estimated 2 billion people with latent tuberculosis infection form a reservoir that sustains the global epidemic. Analyses of constraints to global tuberculosis control bring four major persisting barriers to the fore. First, weak health systems including the unregulated non-state sector prevent reaching the currently available methods of diagnosis and treatment to all sections of the populations and a lack of universal health coverage and social protection inhibit provision of comprehensive tuberculosis care and prevention without further impoverishment to those who need it most. Second, determinants such as poverty, under nutrition, migration, and ageing populations enhance vulnerability and maintain the cycle of infection and disease. The risk of tuberculosis is further enhanced by non-communicable health problems such as diabetes, harmful use of alcohol, and tobacco smoking. Third, the lack of optimum methods—a point-of-care test for rapid diagnosis of disease and latent infection; better and safer drug regimens to shorten treatment; and a vaccine to prevent Lancet 2015; 385: 1799–801

Antiretroviral Therapy for Prevention of Tuberculosis in Adults with HIV: A Systematic Review and Meta-Analysis

In a systematic review and meta-analysis, Amitabh Suthar and colleagues investigate the association between antiretroviral therapy and the reduction in the incidence of tuberculosis in adults with HIV infection.

Latent Mycobacterium tuberculosis Infection

The natural history of tuberculosis begins with the inhalation of Mycobacterium tuberculosis organisms; a period of bacterial replication and dissemination ensues, followed by immunologic containment of viable bacilli. The result of this process is asymptomatic latent tuberculosis infection, which is defined as a state of persistent bacterial viability, immune control, and no evidence of clinically manifested active tuberculosis. 1 Currently, it is not possible to directly diagnose M. tuberculosis infection in humans; therefore, latent tuberculosis infection is diagnosed by response to in vivo or in vitro stimulation by M. tuberculosis antigens with the use of the tuberculin skin test or interferon-γ release assays (IGRAs). Studies suggest that active tuberculosis will develop in 5 to 15% of persons with latent infection during their lifetimes 2 (and a higher percentage if the persons are immunocompromised); thus, persons with latent infection serve, according to Osler, as the “seedbeds” of tuberculosis in the community. 3 This article will review the pathogenesis, epidemiology, diagnosis, and treatment of latent tuberculosis infection. It will address critical gaps in the understanding of this complex condition and propose the necessary research agenda.

Management of latent Mycobacterium tuberculosis infection: WHO guidelines for low tuberculosis burden countries

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. Guidelines on LTBI for low TB incidence countries – essential element of the @WHO #EndTB strategy and TB elimination http://ow.ly/RW8xn