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Objectives: Numerous studies investigate the advantages of rapid molecular drug susceptibility testing (DST) in comparison to phenotypic DST, but the clinical impact on treating multi/extensively drug resistant TB(M/XDR-TB) is less studied. Therefore, we examined how molecular DST testing may improve MDR-TB treatment management and outcome in Chinese settings. Methods: We performed a comparative study of patient cohorts before and after the implementation of molecular DST diagnosis with Genotype MTBDRsl/MTBDRplus assay in two Chinese hospitals. We collected clinical information including time to sputum culture conversion and final treatment outcome. Results: In total, 242 MDR-TB patients were studied including 114 before (pre-implementation group) and 128 after the implementation (post-implementation group) of molecular DST. Time to MDR-TB diagnosis was significantly reduced for patients in the post-implementation group, as compared to the pre-implementation group (median,16 vs 62 days; P < 0.001). Patients with early available molecular DST results had a more rapid culture conversion (aHR1.94 95% CI: 1.37-2.73; median,12 vs 24 months, respectively; P < 0.001) and higher rate of treatment success (68% vs 47%, P < 0.01). Conclusions: The use of molecular DST in routine care for MDR-TB diagnosis as compared to phenotypic DST was associated with a decreased time to culture conversion and improved treatment outcome, highlighting its important clinical value.

Uzbekistan has a high burden of drug-resistant tuberculosis (TB). Although conventional treatment for multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) has been available since 2013, there has been no systematic documentation about its use and effectiveness. We therefore documented at national level the trends, characteristics, and outcomes of patients with drug-resistant TB enrolled for treatment from 2013–2018 and assessed risk factors for unfavorable treatment outcomes (death, failure, loss to follow-up, treatment continuation, change to XDR-TB regimen) in patients treated in Tashkent city from 2016–2017. This was a cohort study using secondary aggregate and individual patient data. Between 2013 and 2018, MDR-TB numbers were stable between 2347 and 2653 per annum, while XDR-TB numbers increased from 33 to 433 per annum. At national level, treatment success (cured and treatment completed) for MDR-TB decreased annually from 63% to 57%, while treatment success for XDR-TB increased annually from 24% to 57%. On multivariable analysis, risk factors for unfavorable outcomes, death, and loss to follow-up in drug-resistant TB patients treated in Tashkent city included XDR-TB, male sex, increasing age, previous TB treatment, alcohol abuse, and associated comorbidities (cardiovascular and liver disease, diabetes, and HIV/AIDS). Reasons for these findings and programmatic implications are discussed.

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.

Tuberculosis is a severe, infectious disease caused by Mycobacterium tuberculosis. The aim of this review was to present the efficacy of linezolid as an agent against multidrug and extensively drug-resistant tuberculosis as gathered from many recent research studies. Linezolid seems to have strongly the potential of being used as an anti-tuberculosis agent because it blocks bacterial ribosomal protein synthesis. Nevertheless caution is required because of the adverse effects it causes, especially when the linezolid daily dosage exceeds 600 mg. The most severe adverse effects include anemia, peripheral neuropathy, optic neuropathy and thrombocytopenia. Still, more trials and research need to be done in order to gather more information and value the cost-benefit dosage of the treatment.

Background & Objectives: Emergence of drug resistant Tuberculosis (TB) is a major obstacle in the TB control programme of Bangladesh. This study was carried out to detect pre-extensively drug resistant TB (pre-XDR-TB) cases among the multidrug resistant TB (MDR-TB) patients in Bangladesh, as the early detection of pre-XDR-TB can guide clinicians in the appropriate modification of MDR-TB treatment regimen with effective drugs to prevent treatment failure. Methodology: A total of 68 MDR-TB cases were enrolled in this study. Multiplex Real-time PCR was done to detect pre-XDR-TB cases directly from sputum samples of MDR-TB patients. Results: Out of 68 MDR-TB cases 11 (16.18%) cases were detected as pre-XDR-TB. The resistant profile of the 11 pre-XDR-TB revealed 9 (81.82%) cases of fluoroquinolone (FLQ) resistant pre-XDR-TB and 2 (18.18%) cases of injectable second line (ISL) agent resistant pre-XDR-TB. Out of 11 pre-XDR-TB cases 7 (63.64%) cases had history of taking treatment for MDR-TB regularly, 1 (9.09%) case had history of taking treatment for MDR-TB irregularly and 3 (27.27%) cases had no history of taking treatment for MDR-TB. Conclusion: This study encountered a high rate of pre-XDR-TB cases along with a significant number of primarily resistant bacilli which is of concern in the management of MDR-TB. It is evident that Bangladesh is in urgent need to device strategies for rapid and early detection of pre-XDR-TB in order to prevent treatment failure of MDR-TB cases and also to halt the progression of MDR-TB cases to extensively drug resistant TB (XDR-TB), which is not only difficult but also very expensive to treat.

TB is an underappreciated public health threat in developed nations. In 2014, an estimated 9.6 million TB cases and 1.5 million deaths occurred worldwide; 3.3% of these cases resulted from multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) strains. These figures underestimate the economic burden associated with MDR-TB and XDR-TB, as the cost of treating disease caused by these strains can be 9-25 times higher than treating drug-susceptible TB. Developing new drugs, improved diagnostics and new TB vaccines are critical components of a strategy to combat TB in general, and drug-resistant TB in particular. Because Mycobacterium tuberculosis (MTB) has demonstrated a capacity to develop resistance to drugs developed to combat it, it is unlikely that drug-resistant MTB would be 'resistant' to vaccines capable of preventing disease or established infection with drug-sensitive MTB strains. Accordingly, the development of TB vaccines represents an important long-term investment in preventing the spread of drug-resistant TB and achieving WHO's goal of ending the global TB epidemic by 2035. Our current understanding of the epidemiology of drug-resistant TB and the interventions needed to limit its spread, reviewed in this article, illustrates the need for increased financial support for developing new TB drugs, diagnostics and vaccines to meet the WHO goal of TB elimination by 2035.

Introduction In India, almost half of all patients with tuberculosis (TB) seek care in the private sector as the first point of care. The national programme is unable to support such TB patients and facilitate effective treatment, as there is no information on TB and Multi or Extensively Drug Resistant TB (M/XDR-TB) diagnosis and treatment in private sector. Objective To improve this situation, Government of India declared TB a notifiable disease for establishing TB surveillance system, to extend supportive mechanism for TB treatment adherence and standardised practices in the private sector. But TB notification from the private sector is a challenge and still a lot needs to be done to accelerate TB notification. Methods Delhi State TB Control Programme had taken initiatives for improving notification of TB cases from the private sector in 2014. Key steps taken were to constitute a state level TB notification committee to oversee the progress of TB notification efforts in the state and direct ‘one to one’ sensitisation of private practitioners (PPs) (in single PP's clinic, corporate hospitals and laboratories) by the state notification teams with the help of available tools for sensitising the PP on TB notification – TB Notification Government Order, Guidance Tool for TB Notification and Standards of TB Care in India. Results As a result of focussed state level interventions, without much external support, there was an accelerated notification of TB cases from the private sector. TB notification cases from the private sector rose from 341 (in 2013) to 4049 (by the end of March 2015). Conclusion Active state level initiatives have led to increase in TB case notification.

Rationale: Multidrug-resistant tuberculosis (MDR-TB) is a major burden to public health in Europe. Reported treatment success rates are around 50% or less, and cure rates are even lower.Objectives: To document the management and treatment outcome in patients with MDR-TB in Europe.Methods: We performed a prospective cohort study, analyzing management and treatment outcomes stratified by incidence of patients with MDR-TB in Europe. Treatment outcomes were compared by World Health Organization and alternative simplified definitions by the Tuberculosis Network European Trialsgroup (TBNET).Measurements and Main Results: A total of 380 patients with MDR-TB were recruited and followed up between 2010 and 2014 in 16 European countries. Patients in high-incidence countries compared with low-incidence countries were treated more frequently with standardized regimen (83.2% vs. 9.9%), had delayed treatment initiation (median, 111 vs. 28 d), developed more additional drug resistance (23% vs. 5.8%), and had increased mortality (9.4% vs. 1.9%). Only 20.1% of patients using pyrazinamide had proven susceptibility to the drug. Applying World Health Organization outcome definitions, frequency of cure (38.7% vs. 9.7%) was higher in high-incidence countries. Simplified outcome definitions that include 1 year of follow-up after the end of treatment showed similar frequency of relapse-free cure in low-(58.3%), intermediate-(55.8%), and high-incidence (57.1%) countries, but highest frequency of failure in high-incidence countries (24.1% vs. 14.6%).Conclusions: Conventional standard MDR-TB treatment regimens resulted in a higher frequency of failure compared with individualized treatments. Overall, cure from MDR-TB is substantially more frequent than previously anticipated, and poorly reflected by World Health Organization outcome definitions.

Drug-resistant tuberculosis (TB) has increased at an alarming rate in the WHO European Region. Of the 27 countries worldwide with a high burden of multidrug resistant-TB (MDR-TB), 15 are in the European Region. An estimated 78,000 new cases of MDR-TB occur annually in the Region, of which approximately 10% are extensively drug-resistant (XDR)-TB. In response, the WHO Regional Office for Europe developed a Consolidated Action Plan to Prevent and Combat Multidrug- and Extensively Drug-resistant Tuberculosis (2011-2015). Our objective was to analyse the cost-effectiveness of implementing the plan, with the expected achievements of diagnosing 85% of estimated MDR-TB cases and treating at least 75% successfully. A transmission model, using epidemiological data reported to WHO was developed to calculate expected achievements. WHO-CHOICE database was used for cost analyses. The highly cost-effective plan is expected to prevent the emergence of 250,000 new MDR-TB and 13,000 XDR-TB patients respectively, saving US$7 billion and 120,000 lives. The plan and accompanying Resolution were fully endorsed by the sixty-first session of the WHO Regional Committee for Europe in 2011. Member States need to continuously improve health system performance and address TB determinants. Research and development of new medicines, tools and patient-friendly services are also crucial.

Setting: Klerksdorp-Tshepong Hospital Complex MDR-TB Unit, North-West Province, South Africa. Background: To determine the time to sputum culture conversion (TTSCC) and factors predictive of TTSCC in patients with multi-drug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) in the North-West Province. Methods: A retrospective cohort study, abstracting patient demographic and clinical data, laboratory results, dates of sputum testing and sputum culture conversion results, from medical records of 526 MDR-TB and 47 XDR-TB patients started on TB treatment between 01 January 2012 and 31 December 2014. Predictors of TTSCC were determined by Cox proportional hazards regression. Results: The median age was 38 years (interquartile range 31–47) with 64% being male. Overall, 79% (449) were Human Immunodeficiency Virus (HIV)-infected. The median TTSCC was 56.5 days and 162.5 days for MDR-TB and XDR-TB patients, respectively. In the multivariate analysis, age [hazard ratio (HR): 0.89, 95% confidence interval (CI): 0.96–0.99], being underweight (HR: 0.631.61, 95% CI: 0.451.03–0.882.51), Acid Fast Bacilli (AFB) positivity (HR: 0.72, 95% CI: 0.51–1.01) and having XDR-TB (HR: 0.36. 95% CI: 0.19–0.69) were predictive of longer TTSCC. Conclusion: Predictors of TTSC allow for MDR-TB- and XDR-TB-diagnosed patients to be identified early for effective management. Those with risk factors for delayed sputum culture conversion which are being underweight and having XDR-TB should be monitored carefully during treatment so that they can achieve sputum culture conversion early.

The problem of drug resistant Tuberculosis (TB) is looming large in the developing countries. TB of the skeletal system is rare and the primary extensively drug resistant TB (XDR-TB) of the hip joint has never been reported in the medical literature so far. The present case is a very rare case of primary XDR-TB of right hip joint in an immunocompetent Indian female. The present case is an important addition to the medical literature, as it will serve as a valuable source of information to the medical and surgical fraternity.

Approximately one third of the world population is infected by M. tuberculosis, and a greater and continuing factor that is bolstering the ongoing tuberculosis (TB) epidemic is the human immune deficiency virus (HIV). Further complicating the issue, multidrug resistance (MDR) has arisen worldwide, and by early 2010, 58 countries had reported at least one case of extensively drug resistant TB [1]. For all these reasons, TB prevention through vaccination is a key global health priority [2].

With almost 30% of the world population suffering from tuberculosis (TB) including its resurgence in the developed world, better management of this global threat is highly desired. The emergence of multidrug-resistant TB (MDR-TB) against first-line drugs and extensively drug resistant TB (XDR-TB) due to misuse of second-line antitubercular drugs (ATDs) is a further concern. Recommended treatment involves long term and multiple drug therapy with severe side effects. In this context, nanostructured systems efficiently encapsulating considerable amounts of ATDs, eliciting controlled, sustained and more profound effect to overcome the need to administer ATDs at high and frequent doses, would assist in improving patient compliance and circumvent hepatotoxicity and/or nephrotoxicity/ocular toxicity/ototoxicity associated with the prevalent first-line chemotherapy. Nanostructured delivery systems constitute a wide range of systems varying from liposomes, micelles, micro- and nanoemulsions, to polymeric nanoparticles (PNPs) and solid lipid nanoparticles (SLNs). Improved bioavailability, solubility, stability and biocompatibility make them an ideal choice for delivery of ATDs. Present review comprehensively covers research carried out on first-line antitubercular drug therapy using these nanostructured systems.

Multi Drug and Extensive Drug Resistant Tuberculosis (M/XDR-TB) has been an area of growing concern among clinicians, epidemiologists and public health workers worldwide. Lack of controlled trials in M/XDR-TB patients retard the optimal management of such patients, and guidelines that have been developed largely on expert opinion are crowed with controversies. Lack of effective drugs, improper regimens prescribed by poorly trained doctors and unreliable Drug Susceptibility Test (DST) reports add to the magnimity of the situation. Quality-assured culture and DST are indispensable for the diagnosis of M/XDR-TB. M/XDT-TB must be managed very effectively with careful use of Second-Line Drugs (SLDs) to reduce the morbidity and mortality and transmission of M/XDR-TB. M/XDR-TB is a man made problem and its emergence can be prevented by prompt diagnosis and effective use of first-line drugs in every new patient. The Programmatic Management of Drug Resistance Tuberculosis (PMDT-TB) proposed by the WHO has highlighted the comprehensive management strategy to control MDR-TB. Laboratory services for adequate and timely diagnosis of M/XDR-TB must be strengthened and programmatic management of M.XDR-TB must be scaled up as per target set by global plan. The proper use of second-line drugs must be ensured to cure existing MDR-TB, to reduce its transmission and to prevent XDR-TB. Sound infection control measures to avoid further transmission of M/XDR-TB and research towards the development of new diagnostics, drugs and vaccines should be promoted for proper control of M/XDR-TB.

Tuberculosis (TB) remains a global emergency and is responsible for 1.7 million deaths annually. Widespread global misuse of isoniazid and rifampicin over three decades has resulted in emergence of the ominous spread of multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) globally. These difficult to treat resistant forms of TB are increasingly seen in Asia, Eastern Europe, South America and sub-Saharan Africa, disrupting TB and HIV control programmes. We review the latest available global epidemiological and clinical evidence on drug-resistant TB in HIV-infected and uninfected populations, with focus on Africa where data are scanty because of poor diagnostic and reporting facilities. The difficult management and infection control problems posed by drug-resistant TB in HIV-infected patients are discussed. Given the increasing current global trends in MDR-TB, aggressive preventive and management strategies are urgently required to avoid disruption of global TB control efforts. The data suggest that existing interventions, public health systems and TB and HIV programmes must be strengthened significantly. Political and funder commitment is essential to curb the spread of drug-resistant TB.

Improved infection control, rapid diagnostic tools, enhanced screening strategies, and pharmacokinetic studies are needed., We investigated the emergence and evolution of drug-resistant tuberculosis (TB) in an HIV co-infected population at a South African gold mine with a well-functioning TB control program. Of 128 patients with drug-resistant TB diagnosed during January 2003–November 2005, a total of 77 had multidrug-resistant (MDR) TB, 26 had pre–extensively drug-resistant TB (XDR TB), and 5 had XDR TB. Genotyping suggested ongoing transmission of drug-resistant TB, and contact tracing among case-patients in the largest cluster demonstrated multiple possible points of contact. Phylogenetic analysis demonstrated stepwise evolution of drug resistance, despite stringent treatment adherence. These findings suggested that existing TB control measures were inadequate to control the spread of drug-resistant TB in this HIV co-infected population. Diagnosis delay and inappropriate therapy facilitated disease transmission and drug-resistance. These data call for improved infection control measures, implementation of rapid diagnostics, enhanced active screening strategies, and pharmacokinetic studies to determine optimal dosages and treatment regimens.

Udgivelsesdato: 2008-Sep Global rates of pulmonary tuberculosis (TB) continue to increase. Moreover, resistance of the causative organism Mycobacterium tuberculosis to the two most effective anti-TB medications continue to rise. Now, multi-drug resistant TB (MDR-TB) has progressed to extensively drug resistant TB (XDR-TB) - a M. tuberculosis organism that is resistant to the most effective second line drugs available for the treatment of TB. This review provides detailed, significant evidence that supports the use of an old neuroleptic compound, thioridazine (TZ), for the management of MDR-TB and XDR-TB infections and which has been shown to inhibit efflux pumps of bacteria. The argument has been previously presented but no one seems to be listening - and the disease continues unabated when there is a very good probability that the suggested drug will prove to be effective. When the prognosis is poor, available therapy predictably ineffective and death is inevitable, compassionate therapy with TZ should be contemplated. The risks are small and the rewards great.

Extensive drug resistance in TB is not a new phenomenon. It is created when patients with multidrug-resistant TB (MDR-TB) are treated with second-line anti-TB drugs but fail to be cured. The first principle in managing the risk of extensively drug-resistant TB (XDR-TB) is 'do not generate XDR-TB'. Once it is created, every effort must be made to prevent it from spreading. Health workers and care givers in long-term care facilities and prisons may have a considerable risk of exposure to TB, including XDR-TB. The principles in the control of TB transmission in healthcare settings, long-term care facilities and prisons include early identification and isolation of infectious TB patients, effective treatment of TB as soon as possible, environmental control with proper ventilation and personal protection of healthcare workers and others. Patients with the highest risk of developing XDR-TB are those MDR-TB patients who failed treatment using a second-line regimen and TB patients who have a history of contact with XDR-TB patients. The core principles in managing the risk of XDR-TB for health workers and care givers are reducing the risks of exposure to XDR-TB, becoming infected and developing XDR-TB. If TB has developed, the principles include promptly diagnosing XDR-TB and starting proper treatment.

Background: The treatment of patients with extensively drug resistant TB (XDR-TB) is a major issue due to high level of morbidity and mortality. The objective of this study was to evaluate the efficacy of using linezolid via intravenous infusion versus oral administration until the smear conversion and to compare the main cost of these two regimens. Methods: In the randomized controlled open-label clinical trial 70 individuals with XDR-TB received not less than 5 effective anti-TB drugs, including linezolid during intensive phase of treatment (240 doses) in TB hospital. All patients had centralized model of treatment: hospitalization – until the smear conversion, after this – ambulatory phase. The patients of the main group (n=35) received linezolid 1200 mg daily intravenously until the smear conversion, turning after this to the oral linezolid 600 mg daily before the end of the intensive phase; the patients of the control group (n=35) received oral linezolid 600 mg daily throughout the all intensive phase. Results: In patients of main group sputum conversion achieved in 97.1% vs. 94.3% of control (p>0,05). The time to sputum conversion in the main group was 46 ± 6.0days vs 109 ± 9.2 days, respectively (p Conclusions: Intravenous administration of linezolid in XDR-TB patients resulted to reduction of terms of smear conversion which makes possible to shorten hospital stay on 63 days.

Resistance to anti-tuberculosis (TB) drugs continues to present a major challenge to global public health. Resistance usually develops due to inadequate TB management, including improper use of medications, improper treatment regimens and failure to complete the treatment course. This may be due to an erratic supply or a lack of access to treatment, as well as to patient noncompliance. However, the emergence and transmission of drug-resistant TB, including the recently detected extensively drug resistant TB (XDR-TB), is driven, in part, by the synergistic relationship between TB and HIV (TB/HIV coinfection). There is evidence that persons infected with HIV are more likely to experience XDR-TB. XDR-TB is virtually untreatable with available TB medications. XDR-TB presents a grave global public health threat, particularly in high HIV prevalence settings. The present commentary discusses the current status of XDR-TB and draws attention to the urgency in addressing this problem, for both the global and Canadian public health networks. XDR-TB and the apparent XDR-TB and HIV association warrants further study.

Tuberculosis is the topic of discussion for researchers due to the indocile nature of its causative micro-organism, Mycobacterium tuberculosis H37Rv (MTB). MTB escapes the human immune system by employing different strategies to render the drugs used for treatment ineffective, due to ultimate alterations in genes such as gyr 90, 91 and 94 which make it resistant to different drugs. Different techniques and methodologies are being developed and used to diagnose, treat and prevent the spread of the disease caused due to drug-resistant MTB. Drug resistance is reported from all over the world. Although very less treatment options are available in case of MDR and XDR-TB but still they are curable. HIV co-infection is also a big hurdle in the way of successful treatment of drug resistant TB as drug-drug interaction is an issue. It is better to improve the community medicine system to battle the TB in a better way. Highest percent of people is showing the resistant against INH so one should be careful about this fact while using the INH in regimen.

Multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) represent an emerging public health problem worldwide. The collision of the HIV epidemic with MDR- and XDR-TB has produced disastrous consequences for individual patients, with very high mortality rates reported in outbreaks among HIV-infected individuals. There is evidence of the importance of primary resistance among HIV-infected persons with XDR-TB, while the relevance of acquired resistance during inappropriate treatment among HIV-infected persons is uncertain, and TB case management of HIV-infected and -uninfected persons is based on similar standard practices to ensure treatment adherence. Current data show a limited geographical overlap of the XDR-TB and HIV epidemics: such data must be interpreted cautiously owing to the lack of adequate testing for both conditions. In fact, there are signs of an evolving epidemiological situation characterized by increased outbreak risk in concentrated areas owing to the extension of the HIV epidemic into areas of high MDR-TB prevalence and of the MDR-TB epidemic into areas of high HIV prevalence. There is a paucity of studies on treatment outcome among HIV-infected XDR-TB patients, and the only available report shows extremely high mortality rate and very short survival. Rapid diagnosis of TB and MDR-TB will be pivotal to reduce mortality among persons co-infected with HIV. However, while rapid diagnosis of MDR-TB is feasible with molecular assays on direct specimens, molecular approaches are still insensitive for XDR-TB diagnosis. There is speculative evidence that effective strategies for early HIV diagnosis and treatment will play a role in limiting the spread, and possibly improving the outcome of XDR-TB. Prevention is currently the mainstay of XDR-TB control in HIV communities. Strategies for infection control based on administrative procedures, environmental control and respiratory protection should be a priority for countries where both XDR-TB and HIV are prevalent. However, only the comprehensive implementation of the full Stop TB Strategy may be expected to curb the devastating impact of XDR-TB on HIV-infected persons.

Multidrug-resistant tuberculosis (TB) strains resistant to the fluoroquinolones and streptomycin but susceptible to second-line injection treatment would not be defined as extensively drug-resistant TB. In a cohort of 174 patients with multidrug-resistant TB, we demonstrated that 12 patients with multidrug-resistant TB strains resistant to the fluoroquinolones and streptomycin had significantly better initial and long-term outcomes, compared with 10 patients with extensively drug-resistant TB.

There is an urgent need for new, rapid diagnostics to stem the tide of multidrug-resistant (MDR) and extensively drug-resistant (XDR) TB. Current identification and detection of resistance for the majority of Mycobacteria, including Mycobacterium tuberculosis, require weeks and multiple methodologies to complete. The sheer number and variety of tests required often exceeds the capacity of many laboratories. Current strategies center on improvement of existing tests and development of novel ones. Ultimately, what is needed is a single, rapid, diagnostic for identification and determination of drug resistance in M. tuberculosis. Such a method should be capable of detecting antibiotic resistance for all first- and second-line agents irrespective of the genetic mechanism of resistance. Detection should be achievable directly from clinical specimens. Yet, improved diagnostics are only part of a larger solution. Such a solution must include a comprehensive approach in which careful consideration is given to each particular setting relative to local resources and overall burden of disease. Such an approach is essential for the future of TB control and stemming the tide of MDR-TB and XDR-TB.

The emergence of multidrug-resistant (MDR)-TB and, more recently, of extensively drug-resistant (XDR)-TB is a real threat to achieve TB control and elimination. Over 400,000 new cases of MDR-TB occur each year and, although their number is currently unknown, XDR cases are recognized in every setting where there has been the capacity to detect them. The long-term vision for the full control of MDR-TB requires the scaling-up of culture and drug-susceptibility testing capacity, which is very limited in disease-endemic countries, and the expanded use of high-technology assays for rapid determination of resistance. MDR cases are treatable and well designed regimens, largely based on second-line anti-TB drugs, can considerably improve cure rates. However, treatment regimens need to be markedly improved through the introduction of less toxic and more powerful drugs, thus reducing duration of treatment and tolerability. This is of utmost importance for XDR-TB cases. The prevalence of MDR-TB and XDR-TB are inversely correlated with the quality of TB control and the proper use of second-line anti-TB drugs. Adherence to proper standards of care and control is imperative and a top priority of all TB control efforts. However, the risk of an uncontrollable epidemic of MDR- and XDR-TB is real considering current levels of financing and commitment to care.

Following the urgent call for a response to the extensively drug resistant tuberculosis (XDR-TB) outbreak in Kwazulu-Natal

INFECTIOUS DISEASEAn outbreak of what's called "extensively drug-resistant tuberculosis," or XDR TB, in KwaZulu-Natal Province, South Africa, appears to be nearly twice as large as originally reported. ([Read more][1].) [1]: http://www.sciencemag.org/cgi/content/full/313/5793/1554a