TB and MDR/XDR-TB in European Union and European Economic Area countries: managed or mismanaged?

Computational analysis of RNA methyltransferase Rv3366 as a potential drug target for combating drug-resistant Mycobacterium tuberculosis

Mycobacterium tuberculosis (M.tb) remains a formidable global health threat. The increasing drug resistance among M.tb clinical isolates is exacerbating the current tuberculosis (TB) burden. In this study we focused on identifying novel repurposed drugs that could be further investigated as potential anti-TB drugs. We utilized M.tb RNA methyltransferase Rv3366 (spoU) as a potential drug target due to its imperative activity in RNA modification and no structural homology with human proteins. Using computational modeling approaches the structure of Rv3366 was determined followed by high throughput virtual screening of Food and Drug Administration (FDA) approved drugs to screen potential binders of Rv3366. Molecular dynamics (MD) simulations were performed to assess the drug-protein binding interactions, complex stability and rigidity. Through this multi-step structure-based drug repurposing workflow two promising inhibitors of Rv3366 were identified, namely, Levodopa and Droxidopa. This study highlights the significance of targeting M.tb RNA methyltransferases to combat drug-resistant M.tb. and proposes Levodopa and Droxidopa as promising inhibitors of Rv3366 for future pre-clinical investigations.

Prevalence of Mycobacterium tuberculosis mutations associated with isoniazid and rifampicin resistance: A systematic review and meta-analysis

Tuberculosis (TB) is still one of the leading causes of worldwide death, especially following the emergence of strains resistant to isoniazid (INH) and rifampicin (RIF). This study aimed to systematically review published articles focusing on the prevalence of INH and/or RIF resistance-associated mutations of Mycobacterium tuberculosis isolates in recent years. Literature databases were searched using appropriate keywords. The data of the included studies were extracted and used for a random-effects model meta-analysis. Of the initial 1442 studies, 29 were finally eligible to be included in the review. The overall resistance to INH and RIF was about 17.2% and 7.3%, respectively. There was no difference between the frequency of INH and RIF resistance using different phenotypic or genotypic methods. The INH and/or RIF resistance was higher in Asia. The S315T mutation in KatG (23.7 %), C-15 T in InhA (10.7 %), and S531L in RpoB (13.5 %) were the most prevalent mutations. Altogether, the results showed that due to S531L in RpoB, S315T in KatG, and C-15 T in InhA mutations INH- and RIF-resistant M. tuberculosis isolates were widely distributed. Thus, it would be diagnostically and epidemiologically beneficial to track these gene mutations among resistant isolates.

A five-year review of prevalence and treatment outcomes of pre-extensively drug-resistant plus additional drug-resistant tuberculosis in the Henan Provincial Tuberculosis Clinical Medicine Research Centre

OBJECTIVES

This study investigated the prevalence and significant clinical outcomes of pre-extensively drug-resistant plus additional drug-resistant tuberculosis (pre-XDR-plus) in Henan Provincial Chest Hospital between 2017 and 2021.

METHODS

We analysed and summarized the drug sensitivity test (DST) results of clinical Mycobacterium tuberculosis (MTB) strains in TB patients seeking care in the Tuberculosis Clinical Medical Research Centre of Henan Province between 2017 and 2021. Medical records of pre-extensively drug-resistant plus additional drug-resistant TB patients were statistically analysed, including demographic characteristics, regimens, and outcomes.

RESULTS

Of the 3689 Mycobacterium tuberculosis strains, 639 (17.32%), 353 (9.56%), and 109 (2.95%), multidrug-resistant tuberculosis (MDR-TB), pre-extensively drug-resistant tuberculosis (pre-XDR), and pre-XDR-plus, respectively. The proportion of MDR decreased from 19.1% in 2017 to 17.5% in 2021 (χ² = 0.686, P = 0.407), the proportion of pre-XDR from 11.4% in 2017 to 9.0% in 2021 (χ² = 2.39, P = 0.122), and pre-XDR-plus from 4.7% in 2017 to 1.8% in 2020, with the declining trend was significant (χ² = 9.348, P = 0.002). The most commonly used anti-TB drugs were pyrazinamide (PZA, 37/46, 80.43%) and cycloserine (CS, 32/46, 69.57%), followed by linezolid (LZD, 25/46, 54.35%), protionamide (TH, 25/46, 54.35%), and para-aminosalicylic acid (PAS, 23/46, 50.00%). Patients receiving the LZD regimen were 5 times more likely to have a favourable outcome than those not receiving LZD (OR = 6.421, 95% CI 2.101-19.625, P = 0.001). Patients receiving a regimen containing CS were 4 times more likely to have a favourable outcome compared to those not taking CS (OR = 5.444, 95% CI 1.650-17.926, P = 0.005).

CONCLUSIONS

Our data suggest that the population of pre-XDR-plus had significantly decreased over the past five years in the Henan Provincial Chest Hospital. The COVID-19 and flood disaster affect TB patients' selection of medical services. In addition, the pre-XDR-plus patients whose regimens contain LZD or CS were more likely to have favourable outcomes.

Barriers and enablers to implementing tuberculosis control strategies in EU and European Economic Area countries: a systematic review

Meeting the 2035 WHO targets of reducing tuberculosis incidence by 90% from 2015 levels requires the implementation of country-specific tuberculosis control strategies. This systematic review aims to identify factors that facilitate or impede the implementation of such strategies in EU and European Economic Area (EEA) settings. Focusing on providers of care, health system constraints, and social and political factors, this Review complements available evidence on the accessibility of tuberculosis services to recipients of care. Databases were searched for EU and EEA articles published between Jan 1, 1997, and Nov 6, 2020, that presented empirical data on tuberculosis policies, strategies, guidelines, or interventions. 2061 articles were screened and 65 were included. The most common barrier to tuberculosis control strategies described the divergence of health-care practices from guidelines, often related to inadequate knowledge or perceived usefulness of the guidelines by clinicians. The most commonly identified enabler to tuberculosis control strategies was the documented positive attitudes of health-care workers towards tuberculosis programmes. Divergence between clinical practice and guidelines was described in most EU and EEA settings, indicating the need for a focused review of guideline adherence. Strengths of this study involve its broad inclusion criteria and wide range of tuberculosis control strategies analysed.

Multidisciplinary management of difficult-to-treat drug resistant tuberculosis: a review of cases presented to the national consilium in Uganda

BACKGROUND

Patients with drug resistant tuberculosis (DR-TB) with comorbidities and drug toxicities are difficult to treat. Guidelines recommend such patients to be managed in consultation with a multidisciplinary team of experts (the "TB consilium") to optimise treatment regimens. We describe characteristics and treatment outcomes of DR-TB cases presented to the national DR-TB consilium in Uganda between 2013 and 2019.

METHODS

We performed a secondary analysis of data from a nation-wide retrospective cohort of DR-TB patients with poor prognostic indicators in Uganda. Patients had a treatment outcome documented between 2013 and 2019. Characteristics and treatment outcomes were compared between cases reviewed by the consilium with those that were not reviewed.

RESULTS

Of 1,122 DR-TB cases, 189 (16.8%) cases from 16 treatment sites were reviewed by the consilium, of whom 86 (45.5%) were reviewed more than once. The most frequent inquiries (N = 308) from DR-TB treatment sites were construction of a treatment regimen (38.6%) and management of side effects (24.0%) while the most frequent consilium recommendations (N = 408) were a DR-TB regimen (21.7%) and "observation while on current regimen" (16.6%). Among the cases reviewed, 152 (80.4%) were from facilities other than the national referral hospital, 113 (61.1%) were aged ≥ 35 years, 72 (40.9%) were unemployed, and 26 (31.0%) had defaulted antiretroviral therapy. Additionally, 141 (90.4%) had hepatic injury, 55 (91.7%) had bilateral hearing loss, 20 (4.8%) had psychiatric symptoms and 14 (17.7%) had abnormal baseline systolic blood pressure. Resistance to second-line drugs (SLDs) was observed among 9 (4.8%) cases while 13 (6.9%) cases had previous exposure to SLDs. Bedaquiline (13.2%, n = 25), clofazimine (28.6%, n = 54), high-dose isoniazid (22.8%, n = 43) and linezolid (6.7%, n = 13) were more frequently prescribed among cases reviewed by the consilium than those not reviewed. Treatment success was observed among 126 (66.7%) cases reviewed.

CONCLUSION

Cases reviewed by the consilium had several comorbidities, drug toxicities and a low treatment success rate. Consilia are important "gatekeepers" for new and repurposed drugs. There is need to build capacity of lower health facilities to construct DR-TB regimens and manage adverse effects.

TB management in the European Union/European Economic Area: a multi-centre survey

BACKGROUND:

Essential TB care in the European Union/European Economic Area (EU/EEA) comprises 21 standards for the diagnosis, treatment and prevention of TB that constitute the European Union Standards for Tuberculosis Care (ESTC).

METHODS:

In 2017, we conducted an audit on TB management and infection control measures against the ESTC standards. TB reference centres in five EU/EEA countries were purposely selected to represent the heterogeneous European TB burden and examine geographic variability.

RESULTS:

Data from 122 patients, diagnosed between 2012 and 2015 with multidrug-resistant TB (n = 49), extensively drug-resistant TB (XDR-TB) (n = 11), pre-XDR-TB (n = 29) and drug-susceptible TB (n = 33), showed that TB diagnosis and treatment practices were in general in agreement with the ESTC.

CONCLUSION:

Overall, TB management and infection control practices were in agreement with the ESTC in the selected EU/EEA reference centres. Areas for improvement include strengthening of integrated care services and further implementation of patient-centred approaches.

ERS/ECDC Statement: European Union standards for tuberculosis care, 2017 update

The International Standards for Tuberculosis Care define the essential level of care for managing patients who have or are presumed to have tuberculosis, or are at increased risk of developing the disease. The resources and capacity in the European Union (EU) and the European Economic Area permit higher standards of care to secure quality and timely TB diagnosis, prevention and treatment. On this basis, the European Union Standards for Tuberculosis Care (ESTC) were published in 2012 as standards specifically tailored to the EU setting. Since the publication of the ESTC, new scientific evidence has become available and, therefore, the standards were reviewed and updated.A panel of international experts, led by a writing group from the European Respiratory Society (ERS) and the European Centre for Disease Prevention and Control (ECDC), updated the ESTC on the basis of new published evidence. The underlying principles of these patient-centred standards remain unchanged. The second edition of the ESTC includes 21 standards in the areas of diagnosis, treatment, HIV and comorbidities, and public health and prevention.The ESTC target clinicians and public health workers, provide an easy-to-use resource and act as a guide through all the required activities to ensure optimal diagnosis, treatment and prevention of TB.

Extensively drug-resistant tuberculosis in India: Current evidence on diagnosis & management

Emergence of extensively drug-resistant tuberculosis (XDR-TB) has significantly threatened to jeopardize global efforts to control TB, especially in HIV endemic regions. XDR-TB is mainly an iatrogenically created issue, and understanding the epidemiological and risk factors associated with it is of paramount importance in curbing this menace. Emergence of this deadly phenomenon can be prevented by prompt diagnosis and effective treatment with second-line drugs in rifampicin-resistant TB (RR-TB) as well as multidrug-resistant TB (MDR-TB) patients. Optimal treatment of RR-TB, MDR-TB and XDR-TB cases alone will not suffice to reduce the global burden. The TB control programmes need to prioritize on policies focusing on the effective as well as rational use of first-line drugs in every newly diagnosed drug susceptible TB patients so as to prevent the emergence of drug resistance.

Team approach to manage difficult-to-treat TB cases: Experiences in Europe and beyond

As recommended by the World Health Organization (WHO), optimal management of MDR-TB cases can be ensured by a multi-speciality consultation body known as 'TB Consilium'. This body usually includes different medical specialities, competences and perspectives (e.g., clinical expertise both for adults and children; surgical, radiological and public health expertise; psychological background and nursing experience, among others), thus lowering the risk of making mistakes - or managing the patients inappropriately, in order to improve their clinical outcomes. At present, several high MDR-TB burden countries in the different WHO regions (and beyond) have introduced TB Consilium-like bodies at the national or subnational level to reach consensus on the best treatment approach for their patients affected by TB. In addition, in countries/settings where a formal system of consultation does not exist, specialized staff from MDR-TB reference centres or international organizations usually spend a considerable amount of their working time responding to phone or e-mail clinical queries on how to manage M/XDR-TB cases. The aim of this manuscript is to describe the different experiences with the TB Consilia both at the international level (European Respiratory Society - ERS/WHO TB Consilium) and in some of the countries where this experience operates successfully in Europe and beyond. The Consilium experiences are described around the following topics: (1) history, aims and focus; (2) management and funding; (3) technical functioning and structure; (4) results achieved. In addition a comparative analysis of the TB Consilia in the different countries has been performed.

Extensively drug resistant tuberculosis in Mali: a case report

Background

Drug resistant tuberculosis presents a major public health challenge.

Case presentation

We present here the first two patients diagnosed with extensively drug resistant tuberculosis in Bamako, Mali. Genotypic findings suggest possible nosocomial transmission from the first patient to the second one, resulting in superinfection of the second patient. After being diagnosed with extensively drug resistant tuberculosis in August 2016, the patients only started receiving appropriate treatment 10 months later.

Conclusion

The identification of these patients highlights the need for improved diagnostic and treatment algorithms for better surveillance and management of drug resistance in Mali. In the interest of these as well as future patients suffering from resistant tuberculosis, all steps recommended for programmatic management of drug resistant tuberculosis must be urgently prioritized in order to strengthen the multidrug resistant tuberculosis program.

Monitoring and managing antibiotic resistance in refugee children

INTRODUCTION

The past decade the Middle East and Southeastern Europe have witnessed an enormous movement of refugees due to the Syrian war and conflicts in Asia and Africa. Although carriage of and infections with multi-drug resistant (MDR) pathogens in refugees have been reported, pediatric data are scarce. Areas covered: MDR bacterial carriage and infections, and MDR-tuberculosis (TB) in refugee children from 2010. Expert commentary: High MDR carriage rates in refugee children are attributed to high pre-civil war MDR rates, war-damaged infrastructure and healthcare systems, and poor hygiene conditions. Currently there are no international guidelines about MDR screening in refugee children. Given the medical importance of MDRs, challenging therapeutics and risk of importation in non/low-endemic countries, we recommend routine screening and contact isolation upon hospitalization of refugees. TB, including MDR-TB, is highly-endemic in many Asian and African countries, however, current data in refugee children are lacking. TB Screening in refugees is widely implemented but there is no consensus on methods and target populations. Coordinated TB detection and treatment, use of rapid molecular tests and drug-susceptibility testing, better access to healthcare, cross border TB care collaboration, and protection from deportation while on treatment should be integrated parts of TB control and prevention.

Treating tuberculosis with high doses of anti-TB drugs: mechanisms and outcomes

Tuberculosis (TB) is considered as one of the most serious threats to public health in many parts of the world. The threat is even more severe in the developing countries where there is a lack of advanced medical amenities and contemporary anti-TB drugs. In such situations, dosage optimization of existing medication regimens seems to be the only viable option. Therapeutic drug monitoring study results suggest that high-dose treatment regimens can compensate the low serum concentration of anti-TB drugs and shorten the therapy duration. The article presents a critical review on the possible changes that occur in the host and the pathogen upon the administration of standard and high-dose regimens. Some of the most common factors that are responsible for low anti-TB drug concentrations in the serum are differences in hosts' body weight, metabolic processing of the drug, malabsorption and/or drug-drug interaction. Furthermore, failure to reach the cavitary pulmonary and extrapulmonary tissues also contributes to the therapeutic inefficiency of the drugs. In such conditions, administration of higher doses can help in compensating the pathogenic outcomes of enhancement of the pathogen's physical barriers, efflux pumps and genetic mutations. The present article also presents a summary of the recorded treatment outcomes of clinical trials that were conducted to test the efficacy of administration of high dose of anti-tuberculosis drugs. This review will help physicians across the globe to understand the underlying pathophysiological changes (including side effects) that dictate the clinical outcomes in patients administered with standard and/or high dose anti-TB drugs.

Infection control, genetic assessment of drug resistance and drug susceptibility testing in the current management of multidrug/extensively-resistant tuberculosis (M/XDR-TB) in Europe: A tuberculosis network European Trialsgroup (TBNET) study

AIM

Europe has the highest documented caseload and greatest increase in multidrug and extensively drug-resistant tuberculosis (M/XDR-TB) of all World Health Organization (WHO) regions. This survey examines how recommendations for M/XDR-TB management are being implemented.

METHODS

TBNET is a pan-European clinical research collaboration for tuberculosis. An email survey of TBNET members collected data in relation to infection control, access to molecular tests and basic microbiology with drug sensitivity testing.

RESULTS

68/105 responses gave valid information and were from countries within the WHO European Region. Inpatient beds matched demand, but single rooms with negative pressure were only available in low incidence countries; ultraviolet decontamination was used in 5 sites, all with >10 patients with M/XDR-TB per year. Molecular tests for mutations associated with rifampicin resistance were widely available (88%), even in lower income and especially in high incidence countries. Molecular tests for other first line and second line drugs were less accessible (76 and 52% respectively). A third of physicians considered that drug susceptibility results were delayed by > 2 months.

CONCLUSION

Infection control for inpatients with M/XDR-TB remains a problem in high incidence countries. Rifampicin resistance is readily detected, but tests to plan regimens tailored to the drug susceptibilities of the strain of Mycobacterium tuberculosis are significantly delayed, allowing for further drug resistance to develop.

Prevalence and treatment outcome of extensively drug-resistant tuberculosis plus additional drug resistance from the National Clinical Center for Tuberculosis in China: A five-year review

OBJECTIVES

The objective of this study was to explore the prevalence and primary clinical outcomes of extensively drug-resistant tuberculosis plus addition resistance to all drug tested (XDR-TB-Plus) between 2011 and 2015 in Beijing Chest Hospital.

METHODS

We retrospectively reviewed the drug susceptibility testing (DST) results of clinical Mycobacterium tuberculosis (MTB) strains from TB patients seeking health care in the National Clinical Center for Tuberculosis, between 2011 and 2015. The medical records of patients classified as XDR-TB-Plus were reviewed, including demographic characteristics, treatment regimen, and treatment outcome.

RESULTS

Of 9544 MTB isolates, there were 3376 (35.4%), 842 (8.8%) and 61 (0.64%) isolates identified as multidrug resistant tuberculosis (MDR-TB), extensively drug resistant tuberculosis (XDR-TB) and XDR-TB-Plus, respectively. The proportion of XDR-TB showed significant increase from 6.3% in 2011 to 9.1% in 2015 (Chi-square trend 5.94, P = 0.015). Similarly, the proportion of XDR-TB-Plus seemed to increase from 0.46% in 2011 to 0.74% in 2015, while the increasing trend was not significant (Chi-square trend 1.50, P = 0.221). The most frequently prescribed anti-TB drug was moxifloxacin (18/29, 62.1%), followed by protionamide (16/29, 55.2%), clofazimine (15/29, 51.7%), and pyrazinamide (15/29, 51.7%). Patients receiving regimens containing linezolid (LZD) were almost 27 times more likely to have favorable treatment outcome compared with those receiving regimens without LZD [odds ratios = 27.00; 95% CI = 2.50-291.19; P = 0.003].

CONCLUSIONS

In conclusion, our data have demonstrated that the proportion of XDR-TB has significantly increased over the past five years in Beijing Chest Hospital. In addition, the XDR-TB-Plus patients were more likely to reach favorable clinical outcome under the treatment of regimen containing LZD.

Investigation of pre-XDR Beijing Mycobacterium tuberculosis transmission to a healthcare worker in France, 2016

A case of occupational contamination of a healthcare worker by a pre-extensively drug-resistant (pre-XDR) Beijing strain of Mycobacterium tuberculosis at the University Hospital of Montpellier, France is reported. The index case was identified using genetic fingerprinting of isolates. This report underscores the risk of healthcare-associated contamination by pre-XDR tuberculosis (TB) in low-incidence countries and the importance of molecular tools for TB care. It also calls for increased vigilance in the management of multi-drug-resistant/XDR TB patients.

Health system factors influencing management of multidrug-resistant tuberculosis in four European Union countries - learning from country experiences

BACKGROUND

In the European Union and European Economic Area only 38% of multidrug-resistant tuberculosis patients notified in 2011 completed treatment successfully at 24 months' evaluation. Socio-economic factors and patient factors such as demographic characteristics, behaviour and attitudes are associated with treatment outcomes. Characteristics of healthcare systems also affect health outcomes. This study was conducted to identify and better understand the contribution of health system components to successful treatment of multidrug-resistant tuberculosis.

METHODS

We selected four European Union countries to provide for a broad range of geographical locations and levels of treatment success rates of the multidrug-resistant tuberculosis cohort in 2009. We conducted semi-structured interviews following a conceptual framework with representatives from policy and planning authorities, healthcare providers and civil society organisations. Responses were organised according to the six building blocks of the World Health Organization health systems framework.

RESULTS

In the four included countries, Austria, Bulgaria, Spain, and the United Kingdom, the following healthcare system factors were perceived as key to achieving good treatment results for patients with multidrug-resistant tuberculosis: timely diagnosis of drug-resistant tuberculosis; financial systems that ensure access to a full course of treatment and support for multidrug-resistant tuberculosis patients; patient-centred approaches with strong intersectoral collaboration that address patients' emotional and social needs; motivated and dedicated healthcare workers with sufficient mandate and means to support patients; and cross-border management of multidrug-resistant tuberculosis to secure continuum of care between countries.

CONCLUSION

We suggest that the following actions may improve the success of treatment for multidrug-resistant tuberculosis patients: deployment of rapid molecular diagnostic tests; development of context-specific treatment guidance and criteria for hospital admission and discharge in the European context; strengthening patient-centred approaches; development of collaborative mechanisms to ensure cross-border care, and development of long-term sustainable financing strategies.

Agents of change: The role of healthcare workers in the prevention of nosocomial and occupational tuberculosis

Healthcare workers (HCWs) play a central role in global tuberculosis (TB) elimination efforts but their contributions are undermined by occupational TB. HCWs have higher rates of latent and active TB than the general population due to persistent occupational TB exposure, particularly in settings where there is a high prevalence of undiagnosed TB in healthcare facilities and TB infection control (TB-IC) programmes are absent or poorly implemented. Occupational health programmes in high TB burden settings are often weak or non-existent and thus data that record the extent of the increased risk of occupational TB globally are scarce. HCWs represent a limited resource in high TB burden settings and occupational TB can lead to workforce attrition. Stigma plays a role in delayed diagnosis, poor treatment outcomes and impaired well-being in HCWs who develop TB. Ensuring the prioritization and implementation of TB-IC interventions and occupational health programmes, which include robust monitoring and evaluation, is critical to reduce nosocomial TB transmission to patients and HCWs. The provision of preventive therapy for HCWs with latent TB infection (LTBI) can also prevent progression to active TB. Unlike other patient groups, HCWs are in a unique position to serve as agents of change to raise awareness, advocate for necessary resource allocation and implement TB-IC interventions, with appropriate support from dedicated TB-IC officers at the facility and national TB programme level. Students and community health workers (CHWs) must be engaged and involved in these efforts. Nosocomial TB transmission is an urgent public health problem and adopting rights-based approaches can be helpful. However, these efforts cannot succeed without increased political will, supportive legal frameworks and financial investments to support HCWs in efforts to decrease TB transmission.

Breaking the barriers: Migrants and tuberculosis

Tuberculosis (TB) can represent an important clinical and public health in developing and developed countries. Low- and middle-income countries are facing an epidemic which is difficult to address because of the drug-resistance spread and the association of TB with HIV/AIDS. High-income countries, whose TB incidence has decreased in the last decades, can be involved in new TB epidemic waves owing to social, healthcare, and economic hurdles and challenges. In particular, migrants coming from high TB incidence countries can represent a new epidemiological issue in the TB care and control in geographical areas where primary care and specialized centres are not equipped to face the clinical and public health issues associated with the TB disease. The healthcare management of individuals with a latent TB infection or the TB disease is heterogeneous and different policies are in place in Europe, and, specifically, in EU countries. Scientific evidence on how to early and efficiently detect TB cases is missing, as well as diagnostic tools to diagnose those who have latent TB infection do not show adequate accuracy. Countries like Greece and Italy have political difficulties in the management of migrants and the poor living conditions in the migration centres can increase the probability of Mycobacterium tuberculosis transmission. A clear advocacy and political commitment are urgently required. The current migration trends represent a threat from a human and a healthcare perspective. New homogeneous and target-oriented policies and strategies are needed to improve the health of the migrant and of the autochthonous populations.

European policies in the management of tuberculosis among migrants

Globally 10.4 million new tuberculosis (TB) incident cases were estimated to have occurred in 2015, of which 3% were reported in the World Health Organization European Region. Importantly, about 25% of the global multidrug-resistant TB (MDR-TB) cases are reported in the European Region, representing one of the greatest challenges to TB control; these are reported particularly in the countries of the Former Soviet Union. Over a quarter of TB cases in the European Union and European Economic Area (EU/EEA) are reported among foreign-born individuals. In line with the recent increase of migration flows towards Europe, TB among migrant populations is also on the rise, emphasizing the need for a better understanding of the TB trends at the regional and sub-regional levels, and of the existing policies on migrants and refugees. The present article is aimed at describing the policies and practices of European countries with a low and intermediate TB incidence with regard to the detection and management of TB and latent TB infection (LTBI) among refugees in Europe.

Recent developments in the diagnosis and management of tuberculosis

Tuberculosis (TB) is a major public health issue worldwide, with ~9.6 million new incident cases and 1.5 million deaths in 2014. The End-TB Strategy launched by the World Health Organization in the context of the post-2015 agenda aims to markedly abate the scourge of TB towards global elimination, by improving current diagnostic and therapeutic practices, promoting preventative interventions, stimulating government commitment and increased financing, and intensifying research and innovation. The emergence and spread of multidrug-resistant strains is currently among the greatest concerns, which may hinder the achievement of future goals. It is crucial that primary healthcare providers are sufficiently familiar with the basic principles of TB diagnosis and care, to ensure early case detection and prompt referral to specialised centres for treatment initiation and follow-up. Given their special relationship with patients, they are in the best position to promote educational interventions and identify at-risk individuals as well as to improve adherence to treatment.

Performance of a lateral flow immunochromatography test for the rapid diagnosis of active tuberculosis in a large multicentre study in areas with different clinical settings and tuberculosis exposure levels

BACKGROUND

Tuberculosis (TB) continues to cause an outsized burden of morbidity and mortality worldwide, still missing efficient and largely accessible diagnostic tools determining an appropriate control of the disease. Serological tests have the potentially to impact TB diagnosis, in particular in extreme clinical settings.

METHODS

The diagnostic performances of the TB-XT HEMA EXPRESS (HEMA-EXPRESS) immunochromatographic rapid test for active TB diagnosis, based on use of multiple Mycobacterium tuberculosis (MTB) specific antigens, have been evaluated in a large study multicentre TB case-finding study, in populations with different exposure level to TB. A total of 1,386 subjects were enrolled in the six participating centres in Peru: 290 active-TB and 1,096 unaffected subjects.

RESULTS

The TB prevalence (overall 20.5%) varied between 4.0% and 41.1% in the different study groups. Overall, the HEMA-EXPRESS test had 30.6% sensitivity (range 3.9-77.9%) and 84.6% specificity (range 51.6-97.3%). A significant inverse correlation between test accuracy (overall 73.5%, range 40.4-96.4%) and TB prevalence in the various study populations was observed (Pearson's r=-0.7985; P=0.05).

CONCLUSIONS

HEMA-EXPRESS, is rapid and relatively inexpensive test suitable for routine use in TB diagnosis. In low TB prevalence conditions, test performance appears in line with WHO Target Product Profile for TB diagnostics. Performances appear suboptimal in high TB prevalence settings. Appropriate set-up in operative clinical settings has to be considered for novel serological tests for TB diagnosis, particularly for formats suitable for point-of-care use.

Epidemiology of multidrug-resistant, extensively drug resistant, and totally drug resistant tuberculosis in Middle East countries

The 2015 represent the deadline for the global tuberculosis (TB) targets set through the Millennium Development Goals (MDG). From 2016 and onward, new goals were set to end the global TB epidemic via implementing new campaign entitled "the End TB Strategy". The major hurdle to end TB epidemic in several parts of the world is the emergence and spread of drug resistant Mycobacterium tuberculosis (MTB) strains. The better understanding of the actual global burden of drug resistant tuberculosis would feed into better implementing the End TB Strategy. In this article we summarize the current knowledge on the patterns of drug resistance tuberculosis cases in the Middle East countries. These countries are served by the Eastern Mediterranean Regional Office (EMRO), one out of six regional offices of World Health Organization. Middle East countries are characterized by geographic vicinity and population's interaction. However, they are dissimilar in several aspects such as economy and health infrastructures. Regarding economy, countries in this region are ranging from wealthy to very poor. Prevalence of tuberculosis and patterns drug resistance tuberculosis cases are also following variable trends within countries of this region. In almost all Middle East countries, there is under-reporting of drug-resistance tuberculosis cases. There are shortages in the infrastructures and facilities for detecting the pattern of drug-resistance tuberculosis. For instance, sixout of 14 countries have neither in-country capacity nor a linkage with a partner laboratory for second-line drug susceptibility testing and only 4 countries have registered site performing Xpert MTB/RIF.

WHO strategies for the programmatic management of drug-resistant tuberculosis

INTRODUCTION

Adequate management of drug-resistant tuberculosis (TB), including multidrug- (MDR) and extensively drug-resistant (XDR-) TB are within the priorities of the newly launched World Health Organization's End TB and Elimination Strategies.

AREAS COVERED

This manuscript presents the evidence on the MDR- /XDR-TB epidemiology and discusses how the five recommended priority actions can be applied at the programmatic level to tackle the epidemic: 1) prevent development of MDR-TB thorough high quality treatment of drug- susceptible TB; 2) expand rapid testing and detection of drug-resistant TB; 3) provide immediate access to effective treatment and proper care; 4) prevent transmission through infection control; 5) increase political commitment and financing. A non-systematic review using Pubmed was carried out in addition to additional relevant information taken from the abstracts of international scientific conferences. Expert commentary: Current and future control of MDR-TB significantly relies on the correct use of new diagnostics and new drugs from one side, and on the consistent application of the five core interventions at the programmatic level. In addition, it is mandatory to tackle the social determinants and socio-economic barriers favouring the MDR-TB, otherwise it will not be possible to reach the planned goals as well as TB Elimination.

Preventing the spread of multidrug-resistant tuberculosis and protecting contacts of infectious cases

Prevention of multidrug-resistant and extensively drug-resistant tuberculosis (MDR/XDR-TB) is a top priority for global TB control, given the need to limit epidemic spread and considering the high cost, toxicity and poor treatment outcomes with available therapies. We performed a systematic literature review to evaluate the evidence for strategies to reduce MDR/XDR-TB transmission and disease progression. Rapid detection and timely initiation of effective treatment is critical to rendering MDR/XDR-TB cases non-infectious. The scale-up of rapid molecular testing has transformed the capacity of high-incidence settings to identify and treat patients with MDR/XDR-TB. Optimized infection control measures in hospitals and clinics are critical to protect other patients and healthcare workers, whereas creative measures to reduce transmission within community hotspots require consideration. Targeted screening of high-risk communities may enhance early case-detection and limit the spread of MDR/XDR-TB. Among infected contacts, preventive therapy promises to reduce the risk of disease progression. This is supported by observational cohort studies, but randomized trials are urgently needed to confirm these observations and guide policy formulation. Substantial investment in MDR/XDR-TB prevention and care will be critical if the ambitious global goal of TB elimination is to be realized.

Tuberculosis care among refugees arriving in Europe: a ERS/WHO Europe Region survey of current practices

No evidence exists on tuberculosis (TB) and latent TB infection (LTBI) management policies among refugees in European countries.A questionnaire investigating screening and management practices among refugees was sent to 38 national TB programme representatives of low and intermediate TB incidence European countries/territories of the WHO European Region.Out of 36 responding countries, 31 (86.1%) reported screening for active TB, 19 for LTBI, and eight (22.2%) reporting outcomes of LTBI treatment. Screening for TB is based on algorithms including different combinations of symptom-based questionnaires, bacteriology and chest radiography and LTBI screening on different combinations of tuberculin skin test and interferon-γ release assays. In 22 (61.1%) countries, TB and LTBI screening are performed in refugee centres. In 22 (61.1%) countries, TB services are organised in collaboration with the private sector. 27 (75%) countries answered that screening for TB is performed as per national and international guidelines, while 19 (52.7%) gave the same answer with regards to LTBI screening. Infection control measures are inadequate in several of the countries surveyed.There is need for improved coordination of TB screening in Europe to implement the End TB Strategy and achieve TB elimination.

Supporting clinical management of the difficult-to-treat TB cases: the ERS-WHO TB Consilium

Multi-drug and extensively drug-resistant tuberculosis (MDR/XDR-TB) are considered a serious threat for TB control and elimination. The outcome of these patients is still largely unsatisfactory as of today, with treatment success rates being consistently below 50% at global level. The World Health Organization (WHO) recommends that management of MDR-TB cases is supported by a specialized team, including complementary medical professionals able to cover several perspectives (clinical, both for adults and children; surgical; radiological; public health; psychological; nursing, among others). Implementation of such a body (known as Consilium in most of the former Soviet Union countries) is often a pre-requisite to apply for international TB control funding and concessionally priced medicines to treat M/XDR-TB cases. The primary objective of the ERS/WHO TB Consilium is to provide clinical consultation for drug-resistant TB and other difficult-to-treat TB cases, including co-infection with HIV and paediatric cases. Through technical guidance to clinicians managing complex TB cases, the main contribution and outcome of the initiative will be a public health response aimed at achieving correct treatment of affected patients and preventing further development of drug resistance. The Consilum's secondary objective is to ensure monitoring and evaluation of clinical practices on the ground (diagnosis, treatment and prevention).

Therapeutic drug monitoring: how to improve drug dosage and patient safety in tuberculosis treatment

In this article we describe the key role of tuberculosis (TB) treatment, the challenges (mainly the emergence of drug resistance), and the opportunities represented by the correct approach to drug dosage, based on the existing control and elimination strategies. In this context, the role and contribution of therapeutic drug monitoring (TDM) is discussed in detail. Treatment success in multidrug-resistant (MDR) TB cases is low (62%, with 7% failing or relapsing and 9% dying) and in extensively drug-resistant (XDR) TB cases is even lower (40%, with 22% failing or relapsing and 15% dying). The treatment of drug-resistant TB is also more expensive (exceeding €50,000 for MDR-TB and €160,000 for XDR-TB) and more toxic if compared to that prescribed for drug-susceptible TB. Appropriate dosing of first- and second-line anti-TB drugs can improve the patient's prognosis and lower treatment costs. TDM is based on the measurement of drug concentrations in blood samples collected at appropriate times and subsequent dose adjustment according to the target concentration. The 'dried blood spot' technique offers additional advantages, providing the rationale for discussions regarding a possible future network of selected, quality-controlled reference laboratories for the processing of dried blood spots of difficult-to-treat patients from reference TB clinics around the world.

New anti-tuberculosis drugs and regimens: 2015 update

Over 480 000 cases of multidrug-resistant (MDR) tuberculosis (TB) occur every year globally, 9% of them being affected by extensively drug-resistant (XDR) strains of Mycobacterium tuberculosis. The treatment of MDR/XDR-TB is unfortunately long, toxic and expensive, and the success rate largely unsatisfactory (<20% among cases with resistance patterns beyond XDR).

The aim of this review is to summarise the available evidence-based updated international recommendations to manage MDR/XDR-TB, and to update the reader on the role of newly developed drugs (delamanid, bedaquiline and pretomanid) as well as repurposed drugs (linezolid and meropenem clavulanate, among others) used to treat these conditions within new regimens.

A nonsystematic review based on historical trials results as well as on recent literature and World Health Organization (WHO) guidelines has been performed, with special focus on the approach to managing MDR/XDR-TB.

The new, innovative global public health interventions, recently approved by WHO and known as the “End TB Strategy”, support the vision of a TB-free world with zero death, disease and suffering due to TB. Adequate, universally accessed treatment is a pre-requisite to reach TB elimination. New shorter, cheap, safe and effective anti-TB regimens are necessary to boost TB elimination.

The new WHO post-2015 End TB Strategy will support the efforts that research on new drugs and regimens requireshttp://ow.ly/LnJER

Tuberculosis among migrant populations in the European Union and the European Economic Area

Background: Although tuberculosis (TB) incidence has been decreasing in the European Union/European Economic Area (EU/EEA) in the last decades, specific subgroups of the population, such as migrants, remain at high risk of TB. This study is based on the report ‘Key Infectious Diseases in Migrant Populations in the EU/EEA’ commissioned by The European Centre for Disease Prevention and Control. Methods: We collected, critically appraised and summarized the available evidence on the TB burden in migrants in the EU/EEA. Data were collected through: (i) a comprehensive literature review; (ii) analysis of data from The European Surveillance System (TESSy) and (iii) evidence provided by TB experts during an infectious disease workshop in 2012. Results: In 2010, of the 73 996 TB cases notified in the EU/EEA, 25% were of foreign origin. The overall decrease of TB cases observed in recent years has not been reflected in migrant populations. Foreign-born people with TB exhibit different socioeconomic and clinical characteristics than native sufferers. Conclusion: This is one of the first studies to use multiple data sources, including the largest available European database on infectious disease notifications, to assess the burden and provide a comprehensive description and analysis of specific TB features in migrants in the EU/EEA. Strengthened information about health determinants and factors for migrants’ vulnerability is needed to plan, implement and evaluate targeted TB care and control interventions for migrants in the EU/EEA.

Facing multi-drug resistant tuberculosis

Multi-drug resistant tuberculosis (MDR-TB) is caused by Mycobacterium tuberculosis strains resistant to at least two of the most effective anti-tuberculosis drugs (i.e., isoniazid and rifampicin). Therapeutic regimens based on second- and third-line anti-tuberculosis medicines showed poor efficacy, safety, and tolerability profiles. It was estimated that in 2012 the multi-drug resistant tuberculosis incidence ranged from 300,000 to 600,000 cases, mainly diagnosed in the Eastern European and Central Asian countries. The highest proportion of cases is among individuals previously exposed to anti-tuberculosis drugs. Three main conditions can favour the emergence and spread of multi-drug resistant tuberculosis: the poor implementation of the DOTS strategy, the shortage or the poor quality of the anti-tuberculosis drugs, and the poor therapeutic adherence of the patients to the prescribed regimens. Consultation with tuberculosis experts (e.g., consilium) is crucial to tailor the best anti-tuberculosis therapy. New therapeutic options are necessary: bedaquiline and delamanid seem promising drugs; in particular, during the development phase they demonstrated a protective effect against the emergence of further resistances towards the backbone drugs. In the recent past, other antibiotics have been administered off-label: the most relevant efficacy, safety, and tolerability profile was proved in linezolid-, meropenem/clavulanate-, cotrimoxazole-containing regimens. New research and development activities are needed in the diagnostic, therapeutic, preventive fields.

Extensively drug-resistant tuberculosis: epidemiology and management

The advent of antibiotics for the treatment of tuberculosis (TB) represented a major breakthrough in the fight against the disease. However, since its first use, antibiotic therapy has been associated with the emergence of resistance to drugs. The incorrect use of anti-TB drugs, either due to prescription errors, low patient compliance, or poor quality of drugs, led to the widespread emergence of Mycobacterium tuberculosis strains with an expanding spectrum of resistance. The spread of multidrug-resistant (MDR) strains (ie, strains resistant to both isoniazid and rifampicin) has represented a major threat to TB control since the 1990s. In 2006, the first cases of MDR strains with further resistance to fluoroquinolone and injectable drugs were described and named extensively drug-resistant TB (XDR-TB). The emergence of XDR-TB strains is a result of mismanagement of MDR cases, and treatment relies on drugs that are less potent and more toxic than those used to treat drug-susceptible or MDR strains. Furthermore, treatment success is lower and mortality higher than achieved in MDR-TB cases, and the number of drugs necessary in the intensive phase of treatment may be higher than the four drugs recommended for MDR-TB. Linezolid may represent a valuable drug to treat cases of XDR-TB. Delamanid, bedaquiline, and PA-824 are new anti-TB agents in the development pipeline that have the potential to enhance the cure rate of XDR-TB. The best measures to prevent new cases of XDR-TB are the correct management of MDR-TB patients, early detection, and proper treatment of existing patients with XDR-TB.

Are we missing opportunities to confirm the diagnosis of tuberculosis by microbial culture?

SETTING

Tuberculosis (TB) incidence is rising globally, with drug resistance becoming increasingly problematic. Microbiological confirmation ensures correct anti-tuberculous chemotherapy.

OBJECTIVE/DESIGN

We retrospectively analysed all TB cases diagnosed in Central Manchester in 2009 investigating how often we are not achieving microbiological diagnosis, factors influencing this and whether opportunities to obtain microbiological samples are missed.

RESULTS

128/156 (82%) cases had samples sent for microbiology. Factors affecting this included disease site, with ocular disease least likely to be sampled (p < 0.0001), and patient age (with children less likely to be sampled p = 0.002). Ethnicity did not affect sampling (n.s.). Overall, 92/156 (59%) cases were culture positive. Negative culture was related to specimen type (p < 0.0001) and patient age (p = 0.019), with children significantly less likely to have a positive culture. Ethnicity and disease site did not affect culture results. There was a trend towards culture positivity being more common in pulmonary (75%) than non-pulmonary (46%) disease (n.s.). In only 7 (4%), could samples have been sent where they were originally absent (3) or further samples obtained where the cultures proved to be negative (4).

CONCLUSION

Despite an overall culture positive rate of 59%, opportunities to achieve microbiological confirmation are seldom missed. In our centre, which is typical of UK practice, this lack of capacity to increase microbiological confirmation, particularly in an era of increasing importance of extra-pulmonary TB, is concerning. Improvements in sample acquisition and laboratory methods are urgently required.

Drug resistance beyond extensively drug-resistant tuberculosis: individual patient data meta-analysis

The broadest pattern of tuberculosis (TB) drug resistance for which a consensus definition exists is extensively drug-resistant (XDR)-TB. It is not known if additional drug resistance portends worsened patient outcomes. This study compares treatment outcomes of XDR-TB patients with and without additional resistance in order to explore the need for a new definition. Individual patient data on XDR-TB outcomes were included in a meta-analysis comparing outcomes between XDR alone and three nonmutually exclusive XDR-TB patient groups: XDR plus resistance to all the second-line injectables (sli) and capreomycin and kanamycin/amikacin (XDR+2sli) XDR plus resistance to second-line injectables and to more than one group 4 drug, i.e. ethionamide/protionamide, cycloserine/terizidone or para-aminosalicylic acid (XDR+sliG4) and XDR+sliG4 plus resistance to ethambutol and/or pyrazinamide (XDR+sliG4EZ). Of 405 XDR-TB cases, 301 were XDR alone, 68 XDR+2sli, 48 XDR+sliG4 and 42 XDR+sliG4EZ. In multivariate analysis, the odds of cure were significantly lower in XDR+2sli (adjusted OR 0.4, 95% CI 0.2-0.8) compared to XDR alone, while odds of failure and death were higher in all XDR patients with additional resistance (adjusted OR 2.6-2.8). Patients with additional resistance beyond XDR-TB showed poorer outcomes. Limitations in availability, accuracy and reproducibility of current drug susceptibility testing methods preclude the adoption of a useful definition beyond the one currently used for XDR-TB.

Delamanid improves outcomes and reduces mortality in multidrug-resistant tuberculosis

Multidrug-resistant and extensively drug-resistant tuberculosis (TB) are associated with worse treatment outcomes for patients, including higher mortality, than for drug-sensitive tuberculosis. Delamanid (OPC-67683) is a novel anti-TB medication with demonstrated activity against multidrug-resistant disease. Patients who participated in the previously reported randomised, placebo-controlled trial of delamanid and the subsequent open-label extension trial were eligible to participate in a 24-month observational study designed to capture treatment outcomes. Treatment outcomes, as assessed by clinicians and defined by the World Health Organization, were categorised as favourable and unfavourable. Delamanid treatment groups were combined for analysis, based on their duration of treatment. In total, for 421 (87.5%) out of 481 patients from the original randomised controlled trial, consent was granted for follow-up assessments. Favourable outcomes were observed in 143 (74.5%) out of 192 patients who received delamanid for ≥6 months, compared to 126 (55%) out of 229 patients who received delamanid for ≤2 months. Mortality was reduced to 1.0% among those receiving long-term delamanid versus short-term/no delamanid (8.3%; p<0.001). Treatment benefit was also seen among patients with extensively drug-resistant TB. This analysis suggests that treatment with delamanid for 6 months in combination with an optimised background regimen can improve outcomes and reduce mortality among patients with both multidrug-resistant and extensively drug-resistant TB.

TBNET - Collaborative research on tuberculosis in Europe

Networking is a key feature of scientific success. The Tuberculosis Network European Trialsgroup (TBNET) was founded in 2006 as a non-profit, non-governmental peer-initiated scientific organization to collaboratively address research priorities in the area of tuberculosis in Europe. Today, TBNET is the largest tuberculosis research organization in Europe with nearly 500 members from 22 EU countries and 49 countries worldwide (www.tb-net.org). Apart from small multicenter basic research studies, a particular strength of TBNET is the performance of large collaborative projects, pan-European multicenter studies and database projects. In recent years, research from TBNET has substantially contributed to the understanding of the management, risk and prognosis of patients with multidrug (MDR) and extensively drug-resistant (XDR) tuberculosis and led to a better understanding of the clinical value of novel tests for the identification of adults and children with tuberculosis and latent infection with Mycobacterium tuberculosis. In 2009, two branches of TBNET were founded to specifically address tuberculosis in the pediatric population (ptbnet) and non-tuberculous mycobacterial diseases (NTM-NET). In addition to the research activities, TBNET is developing expert consensus documents for clinical management and provides training and capacity building especially for members from Eastern European countries, where tuberculosis is still a prevalent health problem.

Minimum package for cross-border TB control and care in the WHO European region: a Wolfheze consensus statement

The World Health Organization (WHO) European region estimates that more than 400,000 tuberculosis (TB) cases occur in Europe, a large proportion of them among migrants. A coordinated public health mechanism to guarantee TB prevention, diagnosis, treatment and care across borders is not in place. A consensus paper describing the minimum package of cross-border TB control and care was prepared by a task force following a literature review, and with input from the national TB control programme managers of the WHO European region and the Wolfheze 2011 conference. A literature review focused on the subject of TB in migrants was carried out, selecting documents published during the 11-yr period 2001-2011. Several issues were identified in cross-border TB control and care, varying from the limited access to early TB diagnosis, to the lack of continuity of care and information during migration, and the availability of, and access to, health services in the new country. The recommended minimum package addresses the current shortcomings and intends to improve the situation by covering several areas: political commitment (including the implementation of a legal framework for TB cross-border collaboration), financial mechanisms and adequate health service delivery (prevention, infection control, contact management, diagnosis and treatment, and psychosocial support).

Protecting the tuberculosis drug pipeline: stating the case for the rational use of fluoroquinolones

The use of fluoroquinolones (FQs) to treat lower respiratory tract infections (LTRI) other than tuberculosis (TB) allows selection of FQ-resistant TB when TB is misdiagnosed. This study maps national guidelines on the use of FQs for LRTI in Europe and determines the risk of FQ-resistant TB upon FQ treatment before TB diagnosis. A questionnaire was developed to map existing national LRTI and community-acquired pneumonia (CAP) guidelines. A systematic review and meta-analysis were performed to determine the risk of FQ-resistant TB if prescribed FQs prior to TB diagnosis. 15 (80%) out of 24 responding European Respiratory Society national delegates reported having national LRTI management guidelines, seven including recommendations on FQ use and one recommending FQs as the first-choice drug. 18 out of 24 countries had national CAP management guidelines, two recommending FQ as the drug of choice. Six studies investigating FQ exposure and the risk of FQ-resistant TB were analysed. TB patients had a three-fold higher risk of having FQ-resistant TB when prescribed FQs before TB diagnosis, compared to non FQ-exposed patients (OR 2.81, 95% CI 1.47-5.39). Although the majority of European countries hold national LRTI/CAP guidelines, our results suggest that a risk of developing FQ resistance exists. Further strengthening of, and adherence to, guidelines is needed to ensure rational use of FQs.

European union standards for tuberculosis care

The European Centre for Disease Prevention and Control (ECDC) and the European Respiratory Society (ERS) jointly developed European Union Standards for Tuberculosis Care (ESTC) aimed at providing European Union (EU)-tailored standards for the diagnosis, treatment and prevention of tuberculosis (TB). The International Standards for TB Care (ISTC) were developed in the global context and are not always adapted to the EU setting and practices. The majority of EU countries have the resources and capacity to implement higher standards to further secure quality TB diagnosis, treatment and prevention. On this basis, the ESTC were developed as standards specifically tailored to the EU setting. A panel of 30 international experts, led by a writing group and the ERS and ECDC, identified and developed the 21 ESTC in the areas of diagnosis, treatment, HIV and comorbid conditions, and public health and prevention. The ISTCs formed the basis for the 21 standards, upon which additional EU adaptations and supplements were developed. These patient-centred standards are targeted to clinicians and public health workers, providing an easy-to-use resource, guiding through all required activities to ensure optimal diagnosis, treatment and prevention of TB. These will support EU health programmes to identify and develop optimal procedures for TB care, control and elimination.