Great challenges face the global community, including the United States, with the worldwide re-emergence of TB and increased number of multi-drug resistant. GeneXpert for TB diagnosis: planned and purposeful implementation .. for many countries because the software is currently only in English. Diagnosing Pulmonary Tuberculosis with the Xpert MTB/RIF Test . Note: Before starting the test, ensure that the GeneXpert Dx System is.
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Tuberculosis TB continues to be one of the greatest killers in the world due to infectious disease, claiming over 1. Many people die from TB because their diagnosis is delayed, and the epidemic continues to endure because we are unable to significantly reduce transmission with current diagnostics. Sputum smear microscopy remains the most common way to diagnose pulmonary TB.
A more sensitive approach to diagnosis is to culture sputum samples, which can include testing for drug resistance. However, such techniques require expensive and sophisticated laboratory infrastructure and staff, and it can take weeks or months to obtain results.
Realistically, most people who need culture tests to diagnose their TB will not have access to the test results in time to save their lives or to prevent transmission to others. However, a key question looms large: Do resource-constrained countries have the technical and financial resources to appropriately and adequately implement this new test?
If so, how should they proceed? Xpert is more sensitive than sputum smear microscopy in detecting TB, and it has similar accuracy as culture.
Conventional culture and drug-susceptibility testing [DST] are still required to complete the drug-resistance profile and to monitor treatment. It also has operational limitations, such as the need for a sustained power supply. However, Xpert is intended to be used at facilities close to the patient to reduce the time to diagnosis and TB treatment initiation. Performing the Xpert assay is relatively simple and involves minimal specimen manipulation.
Diagnosing Pulmonary Tuberculosis with the Xpert MTB/RIF Test
However, the numerous operational and programmatic requirements associated with the assay and its results cause implementation to be less easy than expected. Priority requirements include both operational and programmatic considerations. To maximize the impact, these projects support not only machine and cartridge procurement but also the MOHs, by providing tuherculosis technical assistance toward operational and programmatic requirements.
Additionally, the USG supports research studying different implementation models and their potential impact on TB care genexprt management programs, including transmission and mortality. Planning and carrying out activities according to the operational and technical requirements mentioned above is necessary but can be challenging and potentially demanding on countries with limited resources. Cost and infrastructure requirements are key challenges to Xpert implementation.
Efforts to date have identified many other challenges and lessons learned. The actual cost per test will vary by country because of differences in shipping fees, procurement agent and other clearance fees, and the use of required distributers. A reduced pricing scheme for the machine and cartridges for the public sector was negotiated with Cepheid in high TB-burden countries.
The price of Xpert equipment and cartridges is a barrier for scaling up Xpert in many countries.
GeneXpert MTB/RIF – Wikipedia
In countries that already have Xpert machines, we fear that the machines will sit unused after the initial investment unless due attention is given to identifying sustained resources for commodities and recurrent costs. Equipment and supply costs are a barrier to scaling up Xpert in many countries. When, where, and how to use Xpert depends on the national commitment to draft policies and implementation strategies; available funds; accessibility, availability, and geographic distribution of adequate diagnostic services; and the epidemiology of TB in the country especially HIV-associated TB and MDR-TB.
Positioning of Xpert machines in the country needs to balance available resources, national capacity building, and accessibility to persons suspected of having TB that would most benefit from the diagnostic test.
Because it is a new and expensive technology, many countries are placing their first machines in central- and regional-level labs to gain knowledge, build a cadre of staff who can provide technical assistance on the assay, and most importantly, test as many people suspected of having TB as possible. In addition, many countries continue to do parallel diagnostic smear microscopy to preselect persons suspected of having TB and build the local evidence base, but also because their national policies to treat and monitor TB patients rely on smear microscopy status.
Xpert should be incorporated into a diagnostic and treatment algorithm that includes all diagnostic tests needed to place a patient on an adequate drug regimen. Many countries currently have limited ability to address drug-resistant TB.
Lack of TB culture and DST facilities and referral systems continues to delay diagnosis and treatment. Drugs for MDR-TB are available, but they are expensive and often require injections and up to 2 years of treatment. Similarly, weak MDR-TB treatment capacity, including facilities and staff, means that confirmed drug-resistant cases may go untreated until these systems are strengthened.
This poses a substantial dilemma for countries who must weigh the benefits of diagnosing MDR-TB against the ethics of not being able to provide sufficient treatment.
Increased capacity to detect MDR-TB should dictate that countries and their partners significantly ramp up treatment capacity. Training has focused on laboratory staff members who operate the machine and perform the assay. However, clinical staff members need to be sensitized to Xpertso that they properly use the results to inform treatment.
Often, clinicians continue to want smear, culture, and drug-sensitivity test results, even in the presence of an Xpert test result. Clinicians and medical associations need to be included in Xpert stakeholder meetings and trainings. The Xpert assay is a computer-based test. Many facilities have limited technical support to help overcome problems encountered with either the hardware or software. Language is also another barrier for many countries because the software is currently only in English.
Adequate, readily available technical support is needed, in addition to building capacity within the National TB Reference Laboratory system to address potential bottlenecks and technical issues related to implementation. A robust monitoring and evaluation system needs to be put in place, including appropriate indicators and support for data collection, reporting, and analysis. It is especially important to monitor the positive effects that Xpert can have on treatment initiation rates and reduced time to treatment.
Assessment of these effects requires a system that can link diagnostic and clinical information, which is not yet in place in most high-burden countries. Despite the challenges to implementing Xperta number of opportunities for strengthening many aspects of TB prevention, diagnostic, and treatment programs are emerging. Since use of the machine in HIV-treatment settings to diagnose co-infected TB patients is highly recommended, Xpert scale up in these settings may strengthen the coordination between TB and HIV programs.
Although policies to intensify TB case detection among persons with HIV have long been in place, a significant gap remains in on-the-ground collaborative activities. Xpert has the potential to narrow this gap.
Diagnosing Pulmonary Tuberculosis with the Xpert MTB/RIF Test | Protocol
Additionally, implementation of Xpert can be greatly facilitated by leveraging HIV laboratory, care, and treatment infrastructure.
TB programs can garner other lessons learned from HIV programs, which have witnessed rapid implementation of new technologies and treatments. In addition, Cepheid and other companies are looking into performing TB testing and HIV viral load testing on a common instrument.
Similarly, increased detection of MDR-TB should increase the market for second-line anti-TB drugs and potentially drive the cost of these drugs down. Ttuberculosis is still a need for high-quality microscopy, culture, and DST to espzol treatment and outcomes and to complete the susceptibility profile.
Therefore, Xpert roll out should motivate countries to continue strengthening laboratory networks and specimen-referral networks throughout the country to keep up with this demand.
Currently, there are no point-of-care TB diagnostic tools at the stage of evaluation or demonstration that are sufficiently sensitive and specific for TB detection in both populations with and without HIV infection. However, a variety of nucleic acid amplification, alternative antigen, and volatile organic compound detection assays are in the pipeline tubercluosis are proving to have utility in distinct patient populations.
Coordination of Xpert roll out by MOHs and partner and stakeholder working groups will build gneexpert high level of capacity to prepare for promising upcoming changes in technology and tools. Xpert is the most exciting innovation in TB diagnostics in over a century. However, Xpert is not a panacea. Its implementation presents major challenges, particularly related to cost and infrastructure, which call for a thoughtfully phased and careful introduction.
Strong health systems are required in order to realize the full potential of this new technology. Also, Xpert is not a point-of-care test, which remains an important need in TB diagnostics. Fast and accurate detection of TB and MDR-TB needs to happen at the community level with a point-of-care test and a strong laboratory network and referral system to ensure that patients have access to all the diagnostic and follow-up testing they need.
Countries have to make decisions about where to place the test; clinicians have to learn to trust the test results; program managers must embrace the challenges of implementing a new technology; and policy makers must agree to invest with adequate funding for scale up. The findings and tuberculksis in this paper are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention, the United States Agency for International Development, or the U.
Amy Piatek is among a group of inventors who earn royalties on licensing fees for molecular beacon usage. National Center for Biotechnology InformationU. Glob Health Sci Pract. Published online Mar William L Coggin d U. Author information Article notes Copyright and License information Disclaimer. Correspondence to Amy Piatek vog.
Received Nov 9; Accepted Feb This is an open-access article distributed under the terms tubecrulosis the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly cited. To view a copy of this license, visit http: This article has been cited by other articles genexpedt PMC. Capacity for conventional culture and drug-resistance testing through diagnostic referral networks.
Budget to support initial investment of machines and infrastructure and to support running costs for cartridges and calibration. Coordination mechanisms in country, and epidemiological gebexpert SWOT Strengths, Weaknesses, Opportunities, and Threats analysis of diagnostic and treatment situation to guide implementation. Integrating Xpert into national laboratory strategies for both the public and private sectors and country plans for initial implementation, including identifying target groups, defining diagnostic algorithms, selecting appropriate sites, forecasting commodities, and developing an annual activity plan and budget.
Ensuring infrastructure and operational needs are met to begin Xpert testing at designated sites. Building capacity for Xpert implementation, including training of site staff and clinicians. Prioritizing According to Country Circumstances When, where, and how to use Xpert depends on the national commitment to draft policies and genxepert strategies; available funds; accessibility, availability, and geographic distribution of adequate diagnostic services; and the epidemiology tuberculpsis TB in the country especially HIV-associated TB and MDR-TB.
Testing and Treatment Algorithms Xpert should be incorporated into a diagnostic and treatment algorithm that includes all diagnostic tests needed to place a patient on an adequate drug regimen. Genexpery of Both Laboratory and Clinical Staff Training has focused on laboratory staff members who operate the machine and perform the assay.
Technical Support Needs The Xpert assay is a computer-based test. Monitoring and Evaluation A robust monitoring and evaluation system needs to be put in place, including appropriate indicators and support for data collection, reporting, and analysis. Strengthening Other Laboratory Diagnostics There is still a need for high-quality microscopy, culture, and DST to monitor treatment and outcomes and to complete tuberculsis susceptibility profile.
Creating Strong Platforms for New Innovations Currently, there are no point-of-care TB diagnostic tools at the stage of evaluation or demonstration that are sufficiently sensitive and specific for TB detection in both populations with and gensxpert HIV infection. Global tuberculosis control report Optimizing sputum smear microscopy for the diagnosis of pulmonary tuberculosis. Expert Rev Anti Infect Ther. Tuberculosis in patients with human immunodeficiency virus infection.
N Engl J Med.
Rapid detection of Mycobacterium tuberculosis and rifampin resistance by use of on-demand, near-patient technology.