Standardised shorter regimens versus individualised longer regimens for rifampin- or multidrug-resistant tuberculosis.

We sought to compare the effectiveness of two World Health Organization (WHO)-recommended regimens for the treatment of rifampin- or multidrug-resistant (RR/MDR) tuberculosis (TB): a standardised regimen of 9-12 months (the "shorter regimen") and individualised regimens of ≥20 months ("longer regimens").We collected individual patient data from observational studies identified through systematic reviews and a public call for data. We included patients meeting WHO eligibility criteria for the shorter regimen: not previously treated with second-line drugs, and with fluoroquinolone- and second-line injectable agent-susceptible RR/MDR-TB. We used propensity score matched, mixed effects meta-regression to calculate adjusted odds ratios and adjusted risk differences (aRDs) for failure or relapse, death within 12 months of treatment initiation and loss to follow-up.We included 2625 out of 3378 (77.7%) individuals from nine studies of shorter regimens and 2717 out of 13 104 (20.7%) individuals from 53 studies of longer regimens. Treatment success was higher with the shorter regimen than with longer regimens (pooled proportions 80.0% versus 75.3%), due to less loss to follow-up with the former (aRD -0.15, 95% CI -0.17- -0.12). The risk difference for failure or relapse was slightly higher with the shorter regimen overall (aRD 0.02, 95% CI 0-0.05) and greater in magnitude with baseline resistance to pyrazinamide (aRD 0.12, 95% CI 0.07-0.16), prothionamide/ethionamide (aRD 0.07, 95% CI -0.01-0.16) or ethambutol (aRD 0.09, 95% CI 0.04-0.13).In patients meeting WHO criteria for its use, the standardised shorter regimen was associated with substantially less loss to follow-up during treatment compared with individualised longer regimens and with more failure or relapse in the presence of resistance to component medications. Our findings support the need to improve access to reliable drug susceptibility testing.

Guidance for the Evaluation of Tuberculosis Diagnostics That Meet the World Health Organization (WHO) Target Product Profiles: An Introduction to WHO Process and Study Design Principles.

Existing high-priority target product profiles (TPPs) of the World Health Organization (WHO) establish important needs for tuberculosis (TB) diagnostic development. Building on this earlier work, this guidance series aims to provide study guidance for performing accuracy studies of novel diagnostic products that may meet the 4 high-priority WHO TPPs and thus enable adequate evidence generation to inform a WHO evidence review process. Diagnostic accuracy studies represent a fundamental step in the validation of all tests. Unfortunately, such studies often have limitations in design, execution, and reporting, leading to low certainty of the evidence about true test performance, which can delay or impede policy and scale-up decisions. This introductory paper outlines the following: (1) the purpose of this series of papers on study guidance; (2) WHO evidence needs and process for the development of policy guidelines for new TB diagnostic tests; and (3) study design considerations, ie, general diagnostic study considerations, intended use of test and role in the clinical pathway, choice of population and setting, index-test specific issues, suitable reference standard and comparators, study flow and specimen issues, and finally key issues beyond accuracy that should be considered. The other 4 papers in this series will provide more detailed guidance for each of the 4 WHO high-priority TPPs. By increasing the clarity around the clinical evaluation needs for tests that have the potential to meet the TPP specifications, we hope to support harmonized evidence generation and enable the WHO review process towards meeting the WHO End TB Strategy targets for reducing the incidence and mortality associated with TB.

Guidance for Studies Evaluating the Accuracy of Sputum-Based Tests to Diagnose Tuberculosis.

Tests that can replace sputum smear microscopy have been identified as a top priority diagnostic need for tuberculosis by the World Health Organization. High-quality evidence on diagnostic accuracy for tests that may meet this need is an essential requirement to inform decisions about policy and scale-up. However, test accuracy studies are often of low and inconsistent quality and poorly reported, leading to uncertainty about true test performance. Here we provide guidance for the design of diagnostic test accuracy studies of sputum smear-replacement tests. Such studies should have a cross-sectional or cohort design, enrolling either a consecutive series or a random sample of patients who require evaluation for tuberculosis. Adults with respiratory symptoms are the target population. The reference standard should at a minimum be a single, automated, liquid culture, but additional cultures, follow-up, clinical case definition, and specific measures to understand discordant results should also be included. Inclusion of smear microscopy and Xpert MTB/RIF (or MTB/RIF Ultra) as comparators is critical to allow broader comparability and generalizability of results, because disease spectrum can vary between studies and affects relative test performance. Given the complex nature of sputum (the primary specimen type used for pulmonary TB), careful design and reporting of the specimen flow is essential. Test characteristics other than accuracy (such as feasibility, implementation considerations, and data on impact on patient, population and health systems outcomes) are also important aspects.

Guidance for Studies Evaluating the Accuracy of Biomarker-Based Nonsputum Tests to Diagnose Tuberculosis.

The World Health Organization's (WHO) "End TB" strategy calls for development and implementation of novel tuberculosis (TB) diagnostics. Sputum-based diagnostics are challenging to implement and often less sensitive in high-priority populations. Nonsputum, biomarker-based tests may facilitate TB testing at lower levels of the healthcare system, accelerate treatment initiation, and improve outcomes. We provide guidance on the design of diagnostic accuracy studies evaluating nonsputum, biomarker-based tests within the context of WHO's target product profile for such tests. Study designs should account for the intended use when choosing the study population, setting, and reference standards. Although adults with respiratory symptoms may be an initial target population, other high-priority populations regardless of symptoms-including people living with human immunodeficiency virus, those unable to produce sputum samples or with extrapulmonary TB, household contacts, and children-should be considered. Studies beyond diagnostic accuracy that evaluate feasibility and population-level impacts are also needed. A biomarker-based diagnostic may be critical to ending the TB epidemic, but requires appropriate validation before implementation.

Guidance for Studies Evaluating the Accuracy of Rapid Tuberculosis Drug-Susceptibility Tests.

The development and implementation of rapid molecular diagnostics for tuberculosis (TB) drug-susceptibility testing is critical to inform treatment of patients and to prevent the emergence and spread of resistance. Optimal trial planning for existing tests and those in development will be critical to rapidly gather the evidence necessary to inform World Health Organization review and to support potential policy recommendations. The evidence necessary includes an assessment of the performance for TB and resistance detection as well as an assessment of the operational characteristics of these platforms. The performance assessment should include analytical studies to confirm the limit of detection and assay ability to detect mutations conferring resistance across globally representative strains. The analytical evaluation is typically followed by multisite clinical evaluation studies to confirm diagnostic performance in sites and populations of intended use. This paper summarizes the considerations for the design of these analytical and clinical studies.

Fungaemia caused by obstructive renal candida bezoars leads to bilateral chorioretinitis: a case report.

BACKGROUND: Renal fungal bezoars are remarkably rare and mostly occur in immunodeficient patients. Only a small number of cases with immunocompetent patients have been published so far. The published treatment approaches comprised systemic antimycotic therapy and surgical or minimal invasive removal of the fungal balls. In some cases irrigation of the renal duct system with amphotericin B was performed. By obstruction of the urinary tract bezoars can lead to infected hydronephrosis and severe urosepsis with high lethality. Fungaemia can cause fungal colonization in different distant organs. Fulminant chorioretinitis and irreversible visual impairment can be the consequence of ocular fundus colonization. The following report highlights that a co-operation between urologists and ophthalmologists is absolutely indispensible in case of fungaemia. CASE PRESENTATION: Hereinafter we describe a case of an immunocompetent 56 years old woman, presenting with flank pain and shivering. The diagnosis turned out to be difficult due to initially negative urine culture. The fungaemia caused by obstructive nephropathy led to bilateral candida chorioretinitis. The patient was treated with intravenous amphotericin b and the bezoar was removed by percutaneous "nephrolitholapaxy". After two months, a follow up revealed the patient felt well, chorioretinal lesions regressed and urine culture did not show any fungal growth. CONCLUSION: To the best of our knowledge, this is the first case reporting on obstructive renal bezoars, which lead to haematogenous fungus spread and bilateral chorioretinitis. It points out that extensive ophthalmologic examination should be performed in case of fungaemia even if the patient is not suffering from any visual impairment.

World Health Organization treatment guidelines for drug-resistant tuberculosis, 2016 update.

Antimicrobial resistance is a major global concern. Tuberculosis (TB) strains resistant to rifampicin and other TB medicines challenge patient survival and public health. The World Health Organization (WHO) has published treatment guidelines for drug-resistant TB since 1997 and last updated them in 2016 based on reviews of aggregated and individual patient data from published and unpublished studies. An international expert panel formulated recommendations following the GRADE approach. The new WHO guidelines recommend a standardised 9-12 months shorter treatment regimen as first choice in patients with multidrug- or rifampicin-resistant TB (MDR/RR-TB) strains not resistant to fluoroquinolones or second-line injectable agents; resistance to these two classes of core second-line medicines is rapidly detectable with molecular diagnostics also approved by WHO in 2016. The composition of longer regimens for patients ineligible for the shorter regimen was modified. A first-ever meta-analysis of individual paediatric patient data allowed treatment recommendations for childhood MDR/RR-TB to be made. Delamanid is now also recommended in patients aged 6-17 years. Partial lung resection is a recommended option in MDR/RR-TB care. The 2016 revision highlighted the continued shortage of high-quality evidence and implementation research, and reiterated the need for clinical trials and best-practice studies to improve MDR/RR-TB patient treatment outcomes and strengthen policy.

Digital health for the End TB Strategy: developing priority products and making them work.

In 2014, the World Health Organization (WHO) developed the End TB Strategy in response to a World Health Assembly Resolution requesting Member States to end the worldwide epidemic of tuberculosis (TB) by 2035. For the strategy's objectives to be realised, the next 20 years will need novel solutions to address the challenges posed by TB to health professionals, and to affected people and communities. Information and communication technology presents opportunities for innovative approaches to support TB efforts in patient care, surveillance, programme management and electronic learning. The effective application of digital health products at a large scale and their continued development need the engagement of TB patients and their caregivers, innovators, funders, policy-makers, advocacy groups, and affected communities.In April 2015, WHO established its Global Task Force on Digital Health for TB to advocate and support the development of digital health innovations in global efforts to improve TB care and prevention. We outline the group's approach to stewarding this process in alignment with the three pillars of the End TB Strategy. The supplementary material of this article includes target product profiles, as developed by early 2016, defining nine priority digital health concepts and products that are strategically positioned to enhance TB action at the country level.

Institutional Tuberculosis Transmission. Controlled Trial of Upper Room Ultraviolet Air Disinfection: A Basis for New Dosing Guidelines.

RATIONALE: Transmission is driving the global tuberculosis epidemic, especially in congregate settings. Worldwide, natural ventilation is the most common means of air disinfection, but it is inherently unreliable and of limited use in cold climates. Upper room germicidal ultraviolet (UV) air disinfection with air mixing has been shown to be highly effective, but improved evidence-based dosing guidelines are needed. OBJECTIVES: To test the efficacy of upper room germicidal air disinfection with air mixing to reduce tuberculosis transmission under real hospital conditions, and to define the application parameters responsible as a basis for proposed new dosing guidelines. METHODS: Over an exposure period of 7 months, 90 guinea pigs breathed only untreated exhaust ward air, and another 90 guinea pigs breathed only air from the same six-bed tuberculosis ward on alternate days when upper room germicidal air disinfection was turned on throughout the ward. MEASUREMENTS AND MAIN RESULTS: The tuberculin skin test conversion rates (>6 mm) of the two chambers were compared. The hazard ratio for guinea pigs in the control chamber converting their skin test to positive was 4.9 (95% confidence interval, 2.8-8.6), with an efficacy of approximately 80%. CONCLUSIONS: Upper room germicidal UV air disinfection with air mixing was highly effective in reducing tuberculosis transmission under hospital conditions. These data support using either a total fixture output (rather than electrical or UV lamp wattage) of 15-20 mW/m(3) total room volume, or an average whole-room UV irradiance (fluence rate) of 5-7 µW/cm(2), calculated by a lighting computer-assisted design program modified for UV use.

Defining the needs for next generation assays for tuberculosis.

To accelerate the fight against tuberculosis, major diagnostic challenges need to be addressed urgently. Post-2015 targets are unlikely to be met without the use of novel diagnostics that are more accurate and can be used closer to where patients first seek care in affordable diagnostic algorithms. This article describes the efforts by the stakeholder community that led to the identification of the high-priority diagnostic needs in tuberculosis. Subsequently target product profiles for the high-priority diagnostic needs were developed and reviewed in a World Health Organization (WHO)-led consensus meeting. The high-priority diagnostic needs included (1) a sputum-based replacement test for smear-microscopy; (2) a non-sputum-based biomarker test for all forms of tuberculosis, ideally suitable for use at levels below microscopy centers; (3) a simple, low cost triage test for use by first-contact care providers as a rule-out test, ideally suitable for use by community health workers; and (4) a rapid drug susceptibility test for use at the microscopy center level. The developed target product profiles, along with complimentary work presented in this supplement, will help to facilitate the interaction between the tuberculosis community and the diagnostics industry with the goal to lead the way toward the post-2015 global tuberculosis targets.

Multidrug-resistant tuberculosis around the world: what progress has been made?

Multidrug-resistant tuberculosis (MDR-TB) (resistance to at least isoniazid and rifampicin) will influence the future of global TB control. 88% of estimated MDR-TB cases occur in middle- or high-income countries, and 60% occur in Brazil, China, India, the Russian Federation and South Africa. The World Health Organization collects country data annually to monitor the response to MDR-TB. Notification, treatment enrolment and outcome data were summarised for 30 countries, accounting for >90% of the estimated MDR-TB cases among notified TB cases worldwide. In 2012, a median of 14% (interquartile range 6-50%) of estimated MDR-TB cases were notified in the 30 countries studied. In 15 of the 30 countries, the number of patients treated for MDR-TB in 2012 (71 681) was >50% higher than in 2011. Median treatment success was 53% (interquartile range 40-70%) in the 25 countries reporting data for 30 021 MDR-TB cases who started treatment in 2010. Although progress has been noted in the expansion of MDR-TB care, urgent efforts are required in order to provide wider access to diagnosis and treatment in most countries with the highest burden of MDR-TB.

Treatment outcomes of patients with multidrug-resistant and extensively drug-resistant tuberculosis according to drug susceptibility testing to first- and second-line drugs: an individual patient data meta-analysis.

BACKGROUND: Individualized treatment for multidrug-resistant (MDR) tuberculosis and extensively drug-resistant (XDR) tuberculosis depends upon reliable and valid drug susceptibility testing (DST) for pyrazinamide, ethambutol, and second-line tuberculosis drugs. However, the reliability of these tests is uncertain, due to unresolved methodological issues. We estimated the association of DST results for pyrazinamide, ethambutol, and second-line drugs with treatment outcomes in patients with MDR tuberculosis and XDR tuberculosis. METHODS: We conducted an analysis of individual patient data assembled from 31 previously published cohort studies of patients with MDR and XDR tuberculosis. We used data on patients' clinical characteristics including DST results, treatment received, outcomes, and laboratory methods in each center. RESULTS: DST methods and treatment regimens used in different centers varied considerably. Among 8955 analyzed patients, in vitro susceptibility to individual drugs was consistently and significantly associated with higher odds of treatment success (compared with resistance to the drug), if that drug was used in the treatment regimen. Various adjusted and sensitivity analyses suggest that this was not explained by confounding. The adjusted odds of treatment success for ethambutol, pyrazinamide, and the group 4 drugs ranged from 1.7 to 2.3, whereas for second-line injectables and fluoroquinolones, odds ranged from 2.4 to 4.6. CONCLUSIONS: DST for ethambutol, pyrazinamide, and second-line tuberculosis drugs appears to provide clinically useful information to guide selection of treatment regimens for MDR and XDR tuberculosis.

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.

Xpert MTB/RIF for diagnosis of tuberculosis and drug-resistant tuberculosis: a cost and affordability analysis.

Xpert MTB/RIF is a rapid test to diagnose tuberculosis (TB) and rifampicin-resistant TB. Cost and affordability will influence its uptake. We assessed the cost, globally and in 36 high-burden countries, of two strategies for diagnosing TB and multidrug-resistant (MDR)-TB: Xpert with follow-on diagnostics, and conventional diagnostics. Costs were compared with funding available for TB care and control, and donor investments in HIV prevention and care. Using Xpert to diagnose MDR-TB would cost US$70-90 million per year globally and be lower cost than conventional diagnostics globally and in all high-burden countries. Diagnosing TB in HIV-positive people using Xpert would also cost US$90-101 million per year and be lower cost than conventional diagnostics globally and in 33 out of 36 high-burden countries. Testing everyone with TB signs and symptoms would cost US$434-468 million per year globally, much more than conventional diagnostics. However, in European countries, Brazil and South Africa, the cost would represent <10% of TB funding. Introducing Xpert to diagnose MDR-TB and to diagnose TB in HIV-positive people is warranted in many countries. Using it to test everyone with TB signs and symptoms is affordable in several middle-income countries, but financial viability in low-income countries requires large increases in TB funding and/or further price reductions.

Rapid molecular TB diagnosis: evidence, policy making and global implementation of Xpert MTB/RIF.

If tuberculosis (TB) is to be eliminated as a global health problem in the foreseeable future, improved detection of patients, earlier diagnosis and timely identification of rifampicin resistance will be critical. New diagnostics released in recent years have improved this perspective but they require investments in laboratory infrastructure, biosafety and staff specialisation beyond the means of many resource-constrained settings where most patients live. Xpert MTB/RIF, a new assay employing automated nucleic acid amplification to detect Mycobacterium tuberculosis, as well as mutations that confer rifampicin resistance, holds the promise to largely overcome these operational challenges. In this article we position Xpert MTB/RIF in today's TB diagnostic landscape and describe its additional potential as an adjunct to surveillance and surveys, taking into account considerations of pricing and ethics. In what could serve as a model for the future formulation of new policy on diagnostics, we trace the unique process by which the World Health Organization consulted international expertise and systematically assessed published evidence and freshly emerging experience from the field ahead of its endorsement of the Xpert MTB/RIF technology in 2010, summarise subsequent research findings and guidance on who to test and how, and provide perspectives on scaling up the new technology.