Comparison of the Amplisure HBV Quantitative Kit with the Qiagen Artus HBV QS-RGQ Assay for Quantifying Viral DNA in Plasma Samples of Monitoring Cases

Background: Monitoring of hepatitis B virus (HBV) viral load has become an essential phase in the treatment of HBV. There are many commercial assays available for HBV viral load quantification. In this study, we have evaluated the performance characteristics of Amplisure® HBV Kit in comparison with the Qiagen artus HBV QS-RGQ kit for HBV DNA quantitation. Methods: Comparison of 2 methods was carried out on 200 clinical samples, 150 HBV DNA positive and 50 HBV DNA negative, by a reference method. Results obtained with Amplisure® HBV Kit (Amplisure HBV) were compared using the Qiagen artus HBV QS-RGQ assay results as the comparator method. Result: The overall performance of the Amplisure HBV compared with the comparator method shows positive and negative clinical agreement of 100 and 76%, respectively. Among the 12 qualitative discrepant samples, all positive with Amplisure HBV were sequenced and 10 were below comparator method’s LOD. For 5 weak positives (−0.22 to 0.98 log IU/mL), the sequencing failed. The 7 other positives (0.48 to 1.89 log IU/mL) were confirmed positive by sequencing. Quantitative comparison gave an r2 of 0.967 with a mean log difference of 0.09 log10 IU/mL. Conclusion: This study shows that Amplisure® HBV Quantitative Kit shows comparable performance with artus HBV QS-RGQ assays and can be useful in management and therapeutic monitoring of HBV in a clinical practice

Whole-Genome Sequence of Drug-Resistant Mycobacterium tuberculosis Strain S7, Isolated from a Patient with Pulmonary Tuberculosis

Over the past decades, drug-resistant Mycobacterium tuberculosis strains have presented a significant challenge, with inadequate diagnosis of tuberculosis (TB) cases. Here, we report the draft whole-genome sequence of drug-resistant M. tuberculosis strain S7, which was isolated from a patient from Tripura, India, who was diagnosed with pulmonary TB

Is a composite reference standard (CRS) an alternative to culture in assessment and validation of a single tube nested in-house PCR for TB diagnosis?

Introduction: Delay in diagnosis of paucibacillary extra pulmonary tuberculosis (TB) and of smear negative TB has hampered the efforts taken by Control Programs to curb its spread. Better efforts to control spread of TB require more accurate and rapid diagnostic test. Aims: To facilitate early diagnosis of TB directly from clinical specimens, we have standardized and validated the use of a single tube in-house nested PCR in comparison against culture and composite reference standard (CRS). Methods: Single tube nested PCR was performed using primers targeting Insertion Sequence (IS) 6110 of Mycobacterium tuberculosis complex. Microbiological techniques includes AFB smear microscopy, and cultivation on solid egg-based medium (Löwenstein–Jensen [LJ]) and on liquid culture medium using BACTEC MGIT 960 system, BD Microbiology Systems. Results: The sensitivity and specificity of PCR against culture was observed to be 89.7% [95% CI: 84.1–93.5] and 73.1% [95% CI: 67.4–78.1] respectively and that against CRS criteria was 80.2% [95% CI: 75.1–84.5] and 97.1% [95% CI: 92.9–98.9] respectively. PCR showed 100% [111/111, 95% CI: 97–100] sensitivity for smear positive specimens. For smear negative specimens sensitivity and specificity of PCR against culture was observed to be 78.4% [69/88, 95% CI: 68.4–86.5] and 77.3% [204/264, 95% CI: 71.7–82.2] respectively and that against CRS was 68.1% [124/182, 95% CI: 60.8–74.8] and 97.1% [165/170, 95% CI: 93.3–99] respectively. Conclusion: CRS criteria were observed to be better than culture for assessing the diagnostic accuracy of PCR test

Yes, we have the power to end TB!

Robust efforts are essential to sustain and increase the advancements made in battling TB, as well as to tackle persistent issues that have caused the fight against the disease to be uneven. The End TB Strategy proposes that new technologies are to be developed by 2025 to encourage a quick growth in TB occurrence diminishment. This calls for a cross-sectoral focus on creating and distributing suitable medical and programmatic modernizations in a fair manner. However, many difficulties and differences still exist in the realms of research and development regarding vaccines, drugs, technical advances, and services related to TB. Therefore, priority needs to be given to overcoming these difficulties and discrepancies for a better future. On World TB Day 2023, SEAR Union, TB Alliance, the National Institute of Advanced Studies (NIAS) and Open Source Pharma Foundation (OSPF) gathered to discuss an important topic under the heading: “YES, WE HAVE THE POWER TO END TB!” With a commitment to putting the patient first and increasing their collective efforts, the organizations recognized that it is possible to make this goal a reality. The organizations involved in the discussion have declared their commitment to engaging in collaborative efforts to end TB globally. They advocate for strengthening access to TB services, controlling and preventing TB, improving surveillance and drug resistance management, and investing in research and development. Furthermore, they recognize the importance of reducing stigma and integrating patient voices in this endeavour. This Round Table serves as a framework to build on and ensure that the goal of ending TB is achievable

Evaluation of genotype MTBDRsl assay to detect drug resistance associated with fluoroquinolones, aminoglycosides and ethambutol on clinical sediments.

BACKGROUND: The emergence of resistant tuberculosis (TB) is a major setback to the global control of the disease as the treatment of such resistance is complex and expensive. Use of direct detection of mutations by molecular methods could facilitate rapid diagnosis of resistance to offset diagnostic delays. We evaluated the performance of the Genotype MTBDRsl (Hain Life Sciences) for the detection of second line resistant TB directly from stored smear positive sputum sediments. METHODOLOGY/PRINCIPAL FINDINGS: The assay showed a diverse range of sensitivity and specificity, 91.26% [95% CI, 84-96] and 95.5% [95% CI, 87-99] for FQ (PPV ∼97% & NPV ∼ 87.67%), 56.19% [95%CI, 46-66] and 81% [95%CI, 66-91] for EMB (PPV ∼ 88.06% & NPV ∼ 43.21%) and 100% for SLD. Diagnostic accuracy for FQ, SLD and EMB was 94%, 100% and 63.51%, respectively. 1.17% (2/170) were heteroresistance strains, where the heteroresistance was linked to rrs gene. A varying rate of validity was observed 100% (170/170) for FQ, 94.11% (160/170) for EMB, 88.23% (150/170) for SLD. CONCLUSIONS/SIGNIFICANCE: Genotype MTBDRsl is simple, rapid, economical assay that can be used to detect commonly known resistance associated with Fluoroquinolone, second line injectable drugs and ethambutol. The assay detects the targeted resistance in less time as compared to phenotypic DST. But due to low NPV to FQ (88%) and EMB (43.21%), the assay results must be interpreted in coordination with the phenotypic DST

Evaluation of the Indian TrueNAT micro RT-PCR device with GeneXpert for case detection of pulmonary tuberculosis

To evaluate the performance of TrueNAT (RT Micro PCR device) assay in comparison with GeneXpert on sputum samples from pulmonary cases of tuberculosis. 274 samples were processed to detect MTB by ZN smear examination, MGIT culture and molecular methods that included RT-PCR (ABI 7500 & TrueNAT) and GeneXpert for case detection of TB. The overall performance of the test with MGIT(Mycobacterium Growth Indicator Tube) culture as gold standard, sensitivity of smear, RT PCR/TrueNAT and Genexpert was 61.5% (CI:53.3–69.3%), 94.7% (CI:89.8–97.6%) & 96.0% (CI: 91.5–98.5%), respectively. Amongst the S+ (108) samples, RT-PCR/TrueNAT and GeneXpert showed a sensitivity of 99% (CI:94.9%–99.8%) and 100% (98.6%–100.0%), respectively. High concordance was observed between GeneXpert and TrueNAT for case detection of TB. The GeneXpert MTB/RIF test was independent on the user's skills. It has a short turn-around time and simultaneously detects RIF resistance with M. tuberculosis in less than 3 h. The TrueNAT MTB has good sensitivity and specificity in case detection with hands on time of less than 3 h as well as fits the requirements in resourcelimited health care settings. Larger, multi-site studies are required to obtain better estimates of the performance of TrueNAT MTB

Correlating rrs and eis promoter mutations in clinical isolates of Mycobacterium tuberculosis with phenotypic susceptibility levels to the second-line injectables

Objective/background: The in vitro drug-susceptibility testing of Mycobacterium tuberculosis reports isolates as resistant or susceptible on the basis of single critical concentrations. It is evident that drug resistance in M. tuberculosis is quite heterogeneous, and involves low level, moderate level, and high level of drug-resistant phenotypes. Thus, the aim of our study was to correlate rrs (X52917) and eis (AF144099) promoter mutations, found in M. tuberculosis isolates, with corresponding minimum inhibitory concentrations of amikacin, kanamycin, and capreomycin. Methods: Ninety M. tuberculosis clinical isolates were analyzed in this study. The minimum inhibitory concentrations were determined by MGIT 960 for 59 isolates with resistance-associated mutations in the rrs and eis promoter gene regions, and 31 isolates with wild-type sequences, as determined by the GenoType MTBDRsl (version 1) assay. Results: The rrs A1401G mutation was identified in 48 isolates resistant to the second-line injectables. The eis promoter mutations C-14T (n=3), G-10C (n=3), G-10A (n=3), and C-12T (n=2) were found within 11 isolates with various resistance profiles to the second-line injectables. Thirty-one isolates had wild-type sequences for the rrs and eis promoter gene regions of interest, one of which was amikacin, kanamycin, and capreomycin resistant. The isolates with the rrs A1401G mutation had amikacin, kanamycin, and capreomycin minimum inhibitory concentrations of >40 mg/L, >20 mg/L, and 5–15 mg/L, respectively. The isolates with eis promoter mutations had amikacin, kanamycin, and capreomycin minimum inhibitory concentrations of 0.25–1.0 mg/L, 0.625–10 mg/L, and 0.625–2.5 mg/L, respectively. Conclusion: This study provides a preliminary basis for the prediction of phenotypic-resistance levels to the second-line injectables based upon the presence of genetic mutations associated with amikacin, kanamycin, and capreomycin resistance. The results suggest that isolates with eis promoter mutations have consistently lower resistance levels to amikacin, kanamycin, and capreomycin than isolates with the rrs A1401G mutation

Enlistment and outcome of study.

<p>Enlistment and outcome of study.</p