scholarly journals Diagnostic accuracy of Truenat Tuberculosis and Rifampicin-Resistance assays in Addis Ababa, Ethiopia

PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0261084
Author(s):  
Abyot Meaza ◽  
Ephrem Tesfaye ◽  
Zemedu Mohamed ◽  
Betselot Zerihun ◽  
Getachew Seid ◽  
...  

Background Rapid and sensitive Tuberculosis (TB) diagnosis closer to patients is a key global TB control priority. Truenat assays (MTB, MTB Plus, and MTB-RIF Dx) are new TB molecular diagnostic tools for the detection of TB and Rifampicin (RIF)-resistance from sputum samples. The diagnostic accuracy of the assays is needed prior to implementation in clinical use in Ethiopia. This study aimed to determine the sensitivity and specificity of Truenat assays; and aimed to compare the assays to the Xpert MTB/RIF assay. Methods A prospective evaluation study was conducted among 200 presumptive TB patients in microscopy centers in Addis Ababa, Ethiopia from May 2019 to December 2020. Culture (Solid and Liquid methods) and phenotypic (liquid method) drug susceptibility testing (DST) were used as a reference standard. Results Of 200 adult participants, culture confirmed TB cases were 25 (12.5%), and only one isolate was resistant to RIF by phenotypic DST. The sensitivity of Truenat MTB was 88.0% [95% CI 70.1, 95.8], while 91.7 [95% CI 74.2, 97.7] for Truenat MTB Plus at the microscopy centers. The specificity of Truenat MTB was 97.2% [95% CI 93.1, 98.9], while for Truenat MTB Plus was 97.2% [95% CI 93.0, 99.0]. The sensitivity of Truenat MTB was 90.5% while for MTB Plus, 100% compared to the Xpert MTB/RIF assay. Conclusion Truenat assays were found to have high diagnostic accuracy. The assays have the potential to be used as a point of care (POC) TB diagnostic tests.

2021 ◽  
pp. 2100526
Author(s):  
Adam Penn-Nicholson ◽  
Sivaramakrishnan N. Gomathi ◽  
Cesar Ugarte-Gil ◽  
Abyot Meaza ◽  
Evelyn Lavu ◽  
...  

BackgroundBringing reliable and accurate tuberculosis (TB) diagnosis closer to patients is a key priority for global TB control. Molbio Diagnostics have developed the Truenat point-of-care molecular assays for detection of TB and rifampicin (RIF) resistance.MethodsWe conducted a prospective multicentre diagnostic accuracy study at 19 primary health care centres and seven reference laboratories in Peru, India, Ethiopia and Papua New Guinea to estimate the diagnostic accuracy of the point-of-care Truenat MTB, MTB Plus and MTB-RIF Dx assays for pulmonary TB using culture and phenotypic drug susceptibility testing as the reference standard, compared to Xpert MTB/RIF or Ultra.ResultsOf 1807 enrolled participants with TB signs/symptoms, 24% were culture positive for Mycobacterium tuberculosis, of which 15% were RIF-resistant. In microscopy centres, the pooled sensitivity of Truenat MTB and Truenat MTB Plus was 73% [95% CI: 67, 78] and 80% [95% CI: 75, 84], respectively. Among smear-negative specimens, sensitivities were 36% [95% CI: 27, 47] and 47% [95% CI: 37, 58], respectively. Sensitivity of Truenat MTB-RIF was 84% [95% CI: 62, 95]. Truenat assays showed high specificity. Head-to-head comparison in the central reference laboratories suggested that the Truenat assays have similar performance to Xpert MTB/RIF.ConclusionWe found performance of Molbio's Truenat MTB, MTB plus and MTB-RIF Dx assays to be comparable to that of the Xpert MTB/RIF assay. Performing the Truenat tests in primary health care centres with very limited infrastructure was feasible. These data supported the development of a WHO policy recommendation of the Molbio assays.


2017 ◽  
Vol 1 (Special Issue-Supplement) ◽  
pp. 267-267
Author(s):  
Kayzad S. Nilgiriwala ◽  
Louise Pankhurst ◽  
Ali Vaughan ◽  
Zamin Iqbal ◽  
Derrick Crook ◽  
...  

Author(s):  
Anastasiya Kostyusheva ◽  
Sergey Brezgin ◽  
Yurii Babin ◽  
Irina Vasil'eva ◽  
Dmitry Kostyushev ◽  
...  

Infectious diseases are a global health problem affecting billions of people. Developing rapid and sensitive diagnostic tools is key for successful patient management and curbing disease spread. Currently available diagnostics are very specific and sensitive but time-consuming and require expensive laboratory settings and well-trained personnel; thus, they are not available in resource-limited areas, for the purposes of large-scale screenings and in case of outbreaks and epidemics. Developing new, rapid, and affordable point-of-care diagnostic assays is urgently needed. This review focuses on CRISPR-based technologies and their perspectives to become platforms for point-of-care nucleic acid detection methods and as deployable diagnostic platforms that could help to identify and curb outbreaks and emerging epidemics. We describe the mechanisms and function of different classes and types of CRISPR-Cas systems, including pros and cons for developing molecular diagnostic tests and applications of each type to detect a wide range of infectious agents. Many Cas proteins (Cas9, Cas12, Cas13, Cas14) have been leveraged to create highly accurate and sensitive diagnostic tools combined with technologies of signal amplification and fluorescent, potentiometric, colorimetric, or lateral flow assay detection. In particular, the most advanced platforms -- SHERLOCK/v2, DETECTR, or CRISPR-Chip -- enable detection of attomolar amounts of pathogenic nucleic acids with specificity comparable to that of PCR but with minimal technical settings. Further developing CRISPR-based diagnostic tools promises to dramatically transform molecular diagnostics, making them easily affordable and accessible virtually anywhere in the world. The burden of socially significant diseases, frequent outbreaks, recent epidemics (MERS, SARS and the ongoing coronoviral nCov-2019 infection) urgently need the developing of express-diagnostic tools. Recently devised CRISPR-technologies represent the unprecedented opportunity to reshape epidemiological surveillance and molecular diagnostics.


2020 ◽  
Author(s):  
Brett M. Babin ◽  
Gabriela Fernandez-Cuervo ◽  
Jessica Sheng ◽  
Ori Green ◽  
Alvaro A. Ordonez ◽  
...  

AbstractTuberculosis (TB) is a top-ten cause of death worldwide. Successful treatment is often limited by insufficient diagnostic capabilities, especially at the point of care in low-resource settings. The ideal diagnostic must be fast, cheap, and require minimal clinical resources while providing high sensitivity, selectivity, and the ability to differentiate live from dead bacteria. We describe here the development of a Fast, Luminescent, and Affordable Sensor of Hip1 (FLASH) for the diagnosis and monitoring of drug sensitivity of Mycobacterium tuberculosis (Mtb). FLASH is a selective chemiluminescent substrate for the Mtb protease Hip1 that when processed, produces visible light that can be measured with a high signal to noise ratio using inexpensive sensors. FLASH is sensitive to fmol of recombinant Hip1 enzyme in vitro and can detect as few as thousands of Mtb cells in culture or in human sputum samples within minutes. The probe is highly selective for Mtb compared to other non-tuberculous mycobacteria and can distinguish live from dead cells. Importantly, FLASH can be used to measure antibiotic killing of Mtb in culture with greatly accelerated timelines compared to traditional protocols. Overall, FLASH has the potential to enhance both TB diagnostics and drug resistance monitoring in resource-limited settings.One Sentence SummaryA luminescent probe enables sensitive detection of Mycobacterium tuberculosis for diagnostics, treatment monitoring, and drug susceptibility testing.


2021 ◽  
Author(s):  
Adam Penn-Nicholson ◽  
Sophia B Georghiou ◽  
Nelly Ciobanu ◽  
Mubin Kazi ◽  
Manpreet Bhalla ◽  
...  

Background The WHO End TB Strategy requires universal drug susceptibility testing and treatment of all people with tuberculosis. However, available second-line diagnostic tools are cumbersome and require sophisticated laboratory infrastructure, and ultimately less than half of those with drug-resistant tuberculosis receive appropriate treatment. Xpert MTB/XDR was developed to help overcome these limitations. Methods We assessed the diagnostic accuracy of sputum-based Xpert MTB/XDR for isoniazid, fluoroquinolone, ethionamide and second-line injectable resistance detection in adults with an Xpert MTB/RIF or Ultra Mycobacterium tuberculosis-positive result against a composite reference standard of phenotypic drug-susceptibility testing and whole genome sequencing (NCT03728725). Participants with pulmonary tuberculosis symptoms and ≥1 risk factor for drug resistance were consecutively enrolled between four clinical sites in India, Moldova and South Africa. Findings Between 31 July 2019 and 21 March 2020, we enrolled 710 patients, of which 611 (86.1%) had results from index and composite reference standard tests and were included in analysis. The sensitivity of Xpert MTB/XDR was 94% for isoniazid, 95% for fluoroquinolones, 54% for ethionamide, 73% for amikacin, 86% for kanamycin, and 61% for capreomycin resistance detection. Specificity was 98-100% for all drugs. Performance was equivalent to line-probe assays. The non-determinate rate of Xpert MTB/XDR was 2.96%. Interpretation This first prospective, multicentre clinical study of the Xpert MTB/XDR assay demonstrated high diagnostic test accuracy, meeting target product profile criteria for a next-generation drug susceptibility test. Funding German Federal Ministry of Education and Research through KfW, Dutch Ministry of Foreign Affairs, and Australian Department of Foreign Affairs and Trade.


2020 ◽  
Author(s):  
Leonardo Miscio ◽  
Antonio Olivieri ◽  
Francesco Labonia ◽  
Gianfranco De Feo ◽  
Paolo Chiodini ◽  
...  

Abstract Background: The easy access to a quick diagnosis of coronavirus disease 2019 (COVID-19) is a key point to improve the management of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and to contain its spread. Up to now, laboratory real-time PCR is the standard of care, but requires a fully equipped laboratory and significant infrastructure. Consequently, new diagnostic tools are required. Methods: In the present work, the diagnostic accuracy of the point-of-care rapid test "bKIT Virus Finder COVID-19" (Hyris Ltd) is evaluated by a retrospective and a prospective analysis on SARS CoV-2 samples previously assessed with an FDA “authorized for the emergency use - EUA” reference method. Descriptive statistics were used for the present study.Results: Results obtained with the Hyris Kit are the same as that of standard laboratory-based real time PCR methods for all the analyzed samples. In addition, the Hyris Kit provides the test results in less than 2 hours, a significantly shorter time compared to the reference methods, without the need of a fully equipped laboratory. Conclusions: To conclude, the Hyris kit represents a promising tool to improve the health surveillance and to increase the capacity of SARS-CoV-2 testing.


2019 ◽  
Vol 28 (152) ◽  
pp. 180107
Author(s):  
Simon M. Collin ◽  
Fatima Wurie ◽  
Morris C. Muzyamba ◽  
Gerard de Vries ◽  
Knut Lönnroth ◽  
...  

AimsWhat is the evidence base for the effectiveness of interventions to reduce tuberculosis (TB) incidence in countries which have low TB incidence?MethodsWe conducted a systematic review of interventions for TB control and prevention relevant to low TB incidence settings (<10 cases per 100 000 population). Our analysis was stratified according to “direct” or “indirect” effects on TB incidence. Review quality was assessed using AMSTAR2 criteria. We summarised the strength of review level evidence for interventions as “sufficient”, “tentative”, “insufficient” or “no” using a framework based on the consistency of evidence within and between reviews.ResultsWe found sufficient review level evidence for direct effects on TB incidence/case prevention of vaccination and treatment of latent TB infection. We also found sufficient evidence of beneficial indirect effects attributable to drug susceptibility testing and adverse indirect effects (measured as sub-optimal treatment outcomes) in relation to use of standardised first-line drug regimens for isoniazid-resistant TB and intermittent dosing regimens. We found insufficient review level evidence for direct or indirect effects of interventions in other areas, including screening, adherence, multidrug-resistant TB, and healthcare-associated infection.DiscussionOur review has shown a need for stronger evidence to support expert opinion and country experience when formulating TB control policy.


2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Mariusz Dyląg ◽  
Ewa Leniak ◽  
Sebastian Gnat ◽  
Jacek C. Szepietowski ◽  
Lukasz Kozubowski

Abstract Background The impact of Malassezia yeasts on skin mycobiome and health has received considerable attention recently. Pityriasis versicolor (PV), a common dermatosis caused by Malassezia genus worldwide, is a manifestation of dysbiosis. PV can be associated with hyper- and/or hypopigmented skin lesions. This disease entity is characterized by high percentage of relapses, which demands a proper antifungal therapy that is based on unambiguous species identification and drug susceptibility testing. Case presentation Comprehensive analysis of PV case in man presenting simultaneously hyper- and hypopigmented skin lesions was performed. Conventional and molecular diagnostic procedures revealed Malassezia furfur and Malassezia sympodialis, respectively as etiological agents of skin lesions observed. Susceptibility tests showed significantly lowered sensitivity of M. furfur cells to fluconazole. Based on susceptibility profiles local antifungal therapy with drugs characterized by entirely different mechanism of action was included. Conclusions Our study indicates that cases of PV represented by two types of skin lesions in one patient may be associated with distinct Malassezia species. Moreover, as observed in this case, each of the isolated etiological agents of PV may differ significantly in susceptibility to antifungals. This can significantly complicate the treatment of dermatosis, which by definition is associated with a significant percentage of relapses. In the presented case localized topical treatment was sufficient and successful while allowing maintaining the physiological mycobiome.


2018 ◽  
Vol 56 (6) ◽  
pp. e00072-18 ◽  
Author(s):  
Doris Hillemann ◽  
Carsten Haasis ◽  
Sönke Andres ◽  
Tobias Behn ◽  
Katharina Kranzer

ABSTRACT For Mycobacterium tuberculosis complex (MTBC), the rapid and accurate diagnosis of drug resistance is crucial to ensure early initiation of appropriate therapy. Recently, a new molecular diagnostic test, the FluoroType MTBDR, aimed at detecting rifampin and isoniazid resistance has become available. This study aimed to evaluate the FluoroType MTBDR in comparison to phenotypic drug susceptibility testing (DST) using M. tuberculosis complex isolates. MTBC isolates underwent phenotypic DST and were tested using the FluoroType MTBDR and Genotype MTBDRplus. Sanger sequencing of the key regions of rpoB, katG, inhA, and aphC was performed for isolates with discordant phenotypic and molecular results. Furthermore, isolates with specific wild-type bands missing in the Genotype MTBDRplus, indicating the presence of a mutation, were investigated by Sanger sequencing. Specificity and sensitivity, defined as the proportions of isolates correctly determined as susceptible and resistant by the FluoroType MTBDR compared to phenotypic DST, were calculated. A total of 180 culture isolates were included; phenotypic DST showed 85 isolates susceptible to isoniazid and rifampin, 7 with isoniazid monoresistance, 7 with rifampin monoresistance, and 81 with multidrug resistance. The specificity of the FluoroType MTBDR was 100% (95% confidence interval [CI], 96.0 to 100%) for both rifampin and isoniazid. The sensitivity was 91.7% (95% CI, 83.6 to 96.6%) for isoniazid and 98.9% (95% CI, 93.8 to 100.0%) for rifampin. The FluoroType MTBDR has a high sensitivity and specificity for the detection of rifampin and isoniazid resistance when using culture isolates.


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