Detection Of Multidrug-resistant Tuberculosis Research Articles

Evaluation of GeneNAT Real-Time Polymerase Chain Reaction Analyzer and Pre-loaded Chip-Based Mycobacterium tuberculosis and Multidrug-Resistant Tuberculosis Detection in the Diagnosis of Pulmonary Tuberculosis.

Tuberculosis (TB) is still the second causative agent of death worldwide after COVID-19. It is caused by Mycobacterium tuberculosis (MTB) infection. The aim of the current study was to compare the performance of GeneNAT real-time polymerase chain reaction analyzer and pre-loaded chip-based MTB screening and multidrug-resistant tuberculosis (MDR-TB) detection kit (Smart SureTM MTB & MDR-TB, Genetix Biotech Asia Pvt. Ltd., New Delhi, India) against the established WHO-approved GeneXpert Ultra (MTB/rifampicin (RIF)), line probe assay (LPA), and mycobacteriagrowthindicatortube(MGIT) culture at point of care (POC) level. A total of 450 pulmonary TB (PTB) suspect patients were enrolled from October 2023 to March 2024 at the Intermediate Reference Laboratory, Department of Medicine, All India Instituteof Medical Sciences, New Delhi, India. GeneXpert and GeneNAT tests were done directly from sputum specimens. However, processed sputum specimens were used for both LPA (GenoType MTBDRplus) and liquid culture and drug susceptibility testing (MGIT culture and drug susceptibility testing (DST)). On comparing with GeneXpert, for the detection of MTB and rifampicin (RIF), Smart SureTM showed a sensitivity of 98.18% and 97.5% with a specificity of 100% and 98.92%, respectively. While comparing mutations in therpoB gene with LPA, the Smart SureTM MDR-TB kit exhibited sensitivity and specificity of 96.77% and 99.12%, respectively. For katG and inhA genes, sensitivity and specificity were 97.6% & 85.71% and 98.66% & 98.01%, respectively, for both genes. Smart SureTM MDR-TB showed comparable results with MGIT-DST with sensitivity and specificity of 96.88% & 96.15% and 98.99%& 99.02%, respectively, for both RIF and isoniazid (INH) drugs. The GeneNAT system test may provide the status of RIF and INH resistance in PTB cases in a short time with the use of minimal specimens. It required very little infrastructurewith less skilled laboratory staffin comparison with other WHO-approved diagnostics used in resource-limited countries with TB and drug-resistant TB burdens.

Regional differences of Mycobacterium tuberculosis complex infection and multidrug resistance epidemic in Luoyang

BackgroundTuberculosis (TB) remains a global public health event of great concern, however epidemic data on TB covering entire areas during the special period of the COVID-19 epidemic have rarely been reported. We compared the dissemination and multidrug-resistance patterns of Mycobacterium tuberculosis complex (MTBC) in the main urban area of Luoyang City, China (including six municipal jurisdictions) and nine county and township areas under its jurisdiction, aimed to establish the epidemiology of TB in this region and to provide reference for precision anti-TB in places with similar settings.MethodsFrom 2020 to 2022, sputum samples were collected from 18,504 patients with confirmed, suspected and unexcluded TB in 10 designated TB medical institutions. Insertion sequence 6110 was amplified by PCR (rpoB gene detection if necessary) to confirm the presence of MTBC. PCR-positive specimens were analyzed by multicolor melting curve analysis to detect multidrug resistance.ResultsAmong the 18,504 specimens, 2675 (14.5%) were MTBC positive. The positive rate was higher in the main urban area than in the county and township areas (29.8% vs. 10.9%, p < 0.001). Male, re-treated and smear-positive groups were high-burden carriers of MTBC. Individuals aged > 60 years were the largest group infected with MTBC in the main urban area, compared with individuals aged < 61 years in the county and township areas. The detection of multidrug-resistant TB (MDR-TB) was higher in the main urban area than in the county and township areas (13.9% vs. 7.8%, p < 0.001). In all areas, MDR-TB groups were dominated by males, patients with a history of TB treatment, and patients aged < 61 years. Stratified analysis of MDR-TB epidemiology showed that MDR4 (INH þ RIF þ EMB þ SM) was predominant in the main urban area, while MDR3 (INH þ RIF þ SM) was predominant in the county and township areas. MDR-TB detection rate and epidemiology differed among the county and township areas.ConclusionsFor local TB control, it is necessary to plan more appropriate and accurate prevention and control strategies according to the regional distribution of MTBC infection.

Epidemiological characteristics and risk factors of multidrug-resistant tuberculosis in Luoyang, China.

We aimed to examine the prevalence of multidrug-resistant tuberculosis (MDR-TB) in Luoyang, China, identify related risk factors, inform clinical practices, and establish standardized anti-tubercular treatment regimens. We conducted a retrospective analysis of high-resolution melting curve (HRM) data from 17,773 cases (2,748 of which were positive) between June 2019 and May 2022 to assess the prevalence of MDR-TB and to identify its associated risk factors. Between June 2019 and May 2022, out of the 17,773 HRM results, 2,748 were HRM-positive, and 312 were MDR-TB cases. The detection rates for HRM-positive and MDR-TB were 17.0 and 12.1% for males, and 12.4 and 8.2% for females, respectively. The MDR-TB detection rate was higher in the urban areas (14.6%) than in the rural areas (10.6%) and more common among individuals under 51 years of age (14.1%) than those over 50 years of age (9.3%). Notably, the rate of detecting MDR-TB was 18.3% higher in new male patients than in new female patients, which was at 10.6%, and this difference was statistically significant (p < 0.001). Moreover, the rate of MDR detection in females who had received anti-tuberculosis treatment (21.3%) was higher than that in males (16.9%). In the multivariate model that considered the results of the sputum smear and detection time, MDR-TB was positively correlated with a history of tuberculosis (TB) treatment, being male, being younger than 51 years, and living in urban areas. Local TB infections are complex and diverse; therefore, more comprehensive monitoring methods are needed to curb the spread of MDR-TB.

Multi Drug Resistant Tuberculosis Detection by Phenotypic Method inTreatment Naïve Pulmonary Tuberculosis Patients

Background and Aims The emergence of multi drug-resistant tuberculosis MDR-TB in treatment naiumlve Pulmonary Tuberculosis PTB is an epidemiological indicator indicating transmission of drug-resistant strains in the community. This study aimed to assess the patterns of drug resistance to any first-line anti-TB drugs and MDR-TB in culture-positive TB isolates obtained from treatment naiumlve PTB in a tertiary care hospital.Methods A total of 240 culture-positive TB isolates obtained from newly diagnosed pulmonary TB patients during the study period September 2018- June 2021 were enrolled in this study. All culture-positive isolates were subjected to phenotypic drug susceptibility testing DST by the conventional 1 proportion method against all the five first-line anti-tubercular antibiotics.Results Of the 240 isolates 127 52.9 were susceptible to all the first-line anti-tubercular drugs. Mono resistance to Rifampicin Isoniazid Streptomycin and Pyrazinamide was observed in 11 4.6 8 3.3 15 6.3 and 14 5.8 of the isolates respectively. Resistance to Ethambutol was not exhibited by any of the isolates. The proportion of MDR-TB in the study was 12.5.Conclusions The study has identified a high rate of MDR-TB in the study area indicating the need to strengthen and expand the National level TB eradication programmes for early identification and proper treatment to interrupt the chain of transmission of MDR-TB in the community

ПОРІВНЯННЯ СИСТЕМ GENEXPERT MTB/RIF І GENOTYPE ЗІ СТРИПАМИ MTBDRPLUS ДЛЯ ВИЯВЛЕННЯ МУТАЦІЙ, ПОВ’ЯЗАНИХ З РЕЗИСТЕНТНІСТЮ M. TUBERCULOSIS ДО РИФАМПІЦИНУ ПРИ ТУБЕРКУЛЬОЗІ

COMPARISON OF GENEXPERT MTB/RIF AND GENOTYPE SYSTEMS WITH MTBDRPLUS STRIPS FOR DETECTION OF MUTATIONS, ASSOCIATED WITH M. TUBERCULOSIS RESISTANCE TO RIFAMPICIN IN TUBERCULOSIS A. A. Zhurilo, A. I. Barbova, Yu. A. Cherednik, P. S. Trofi mova, S. V. Mironchenko, O. V. Pavlova, A. V. Chernov, L. M. Sladkova Summary The aim was to analyze the level of compliance of two molecular genetic methods GeneXpert MTB/RIF and GenoTypeDRplus in determining the drug resistance of M. tuberculosis to rifampicin when detecting mutations in the RRDR region associated with drug resistance. Object and methods. We studied strains of M. tuberculosis with resistance to rifampicin, which was detected by any of the studied molecular genetic methods. 96 sputum samples were taken. Sputum smears were examined for the presence of acid-fast bacteria by microscopy after staining with the Ziehl-Neelsen method. The material was inoculated into Middlebrook 7H9 broth and on Lowenstein-Jensen medium. The liquid medium was incubated in the BACTEC MGIT system. An immunochromatographic test was used to identify the strains. The drug susceptibility test of M. tuberculosis to rifampicin was performed using the BACTEC MGIT system. The GeneXpert MTB/RIF test was performed according to the manufacturer’s instructions. The GenoTypeDRplus assay was performed on decontaminated and concentrated sputum samples. The process was carried out in three stages: DNA extraction from the processed sputum sample; amplification of the RRDR region by PCR; hybridization of the PCR product to specific oligonucleotide probes immobilized on the test strip. For sequencing, M. tuberculosis DNA isolation was performed using the QIAamp® DNA Mini Kit. The DNA concentration was measured on a Denovix Quantus spectrophotometer. Targeted panel amplification was performed using the Deeplex Myc-TB kit. Amplicon purification was performed using Agencourt AMPure XP magnetic beads. Quantitative analysis of the purified amplification products was performed using a Qubit fluorometer. The M. tuberculosis DNA library was prepared for sample sequencing using the Nextera XT DNA library preparation kit. The library used 5.0 μl of input DNA at a concentration of 0.2 ng/μl. Sequencing was performed on MiSeq equipment with the library normalization and denaturation protocol. Results and discussion. The GeneXpert MTB/RIF and MTBDRplus systems target the same 81 bp rifampicin resistance domain. (RRDR) subunits of bacterial RNA polymerase (rpoB) for mutation detection using DNA probes, i.e. there is a correspondence of probes to each other and an expected similarity of probe binding. We analyzed all sputum samples using GeneXpert MTB/RIF and GenoType MTBDRplus and phenotypic BACCTEC MGIT methods. The level of agreement between two molecular genetic methods for the detection of rifampicin-associated mutations in the RRDR region has been established. The RRDR 81bp region of the rpoB gene of mismatched cases was studied by sequencing. GeneXpert MTB/RIF and GenoType DRplus matched the phenotypic method in 92.7% and 89.6% of cases of M. tuberculosis resistance, respectively. Complete agreement between the results of GeneXpert MTB/RIF and GenoTypeMTBDRplus was observed in 92.7% of cases. GeneXpert MTB/RIF and GenoType DRplus showed a similar pattern of binding failure of wild type probes (WT-probes) when scanning the 81 bp region (RRDRdomain), which leads to stability diagnostics through probe failure software. Sequencing of the RRDR region of “mismatched” strains showed that GeneXpert probes detected seven “mismatched” cases correctly, and GenoTypeDRplus was erroneous in all cases. GeneXpert has demonstrated greater accuracy in R-resistance detection for mismatched isolates compared to GenoTypeDRplus. GeneXpert MTB/RIF has a number of other benefits over GenoTypeDRplus. GeneXpert MTB/RIF is relatively easier to implement, biosafety requirements are minimal, study times are shorter, and the study process is more automated, resulting in less human error and more reproducible results. Given these facts and the results of GeneXpert MTB/RIF found in the study, it is recommended that GeneXpert MTB/RIF be used to detect MDR-TB. Conclusions. Sequencing of the 81bp RRDR region of mismatched M. tuberculosis strains showed that GeneXpert MTB/RIF performed more accurately than GenoTypeDRplus in detecting mutations associated with rifampicin resistance. GeneXpert MTB/RIF is relatively easier to perform, biosafety requirements are minimal, time to study is shorter, and the study process is more automated, resulting in less human error and greater reproducibility of results, so it is reasonable to use it for the detection of multidrug-resistant tuberculosis. The Deeplex Myc-TB analytical solution delivers a wealth of insightful information from antimycobacterial drug resistance markers and speeds up data analysis with easy-to-use software. Key words: tuberculosis, Mycobacterium tuberculosis, drug resistance, GeneXpert MTB/RIF and GenoTypeDRplus molecular genetic systems, BACTEC MGIT phenotypic system, sequencing. Ukr. Pulmonol. J

The pncA gene mutations of Mycobacterium tuberculosis in multidrug-resistant tuberculosis.

The pncA gene encodes pyrazinamidase enzyme which converts drug pyrazinamide to active form pyrazinoic acid, but mutations in this gene can prevent enzyme activity which leads to pyrazinamide resistance. The cross-sectional study was carried out during 2016-2017 for 12 months. The purpose of the study was to detect mutation at codon 12 and codon 85 in the pncA gene in local multidrug-resistant tuberculosis (MDR-TB) patients by developing a simple molecular test so that disease could be detected timely in the local population. DNA extracted from sputum-cultured samples from MDR-TB patients and subjected to semi-multiplex allele-specific PCR by using self-designed primers against the pncA gene. Among 75 samples, 53 samples were subjected to molecular analysis based on purified DNA quantity and quality. The primers produced 250 and 480 bp fragments, indicating the mutations at codon 12 (aspartate to alanine) and codon 85 (leucine to proline) respectively. MDR-TB was more common in the age group 21-40 years. Fifty-seven percent of samples (n = 30) were found positive for pncA mutations, whereas 43% of samples (n = 23) showed negative results. Thirteen percent of samples (n = 4) had mutations at codon 12 in which aspartate was converted to alanine, and they produced an amplified product of 480 bp. Eighty-seven percent of samples (n = 26) had mutations at codon 85 in which leucine was converted to proline and amplified product size was 250 bp. The mutations were simple nucleotide substitutions. The prevalence of mutations in which leucine was substituted by proline was higher than the mutations in which aspartate was substituted by alanine. A high prevalence of substitution mutation (CTG → CCG; leucine to proline) was detected in MDR-TB cases. Earlier detection of MDR-TB via an effective molecular diagnostic method can control the MDR tuberculosis spread in the population.

English

The control of tuberculosis (TB) has become a global health challenge due to the emergence of multidrug-resistant tuberculosis (MDR-TB) in Mycobacterium tuberculosis (MTB). This highlights the need for faster and more accurate detection of tuberculosis cases. The study aims to detect MDR-TB strains of pulmonary tuberculosis using resistance ratio method and to compare the diagnostic value of drug susceptibility testing (DST) with line probe assay (LPA) using Genotype MTBDRplus. All the sputum samples were tested for Acid Fast Bacilli (AFB) by Ziehl-Neelsen&rsquo;s staining method and were cultured on Lowenstein-Jensen (L-J) media. The identification and confirmation of M. tuberculosis were done using various biochemical tests. DST was carried against the first line of anti-TB drugs. MTB positive samples were subjected to LPA. A total of 57 samples were subjected to DST and LPA for the detection of drug resistance of MTB to RIF and INH after conventional detection methods were applied to all the samples. Among these 57 MTB samples, 11 (19.29%) were resistant to INH, 4 (7.14%) were resistant to RIF; eleven (19.29%) isolates were identified as MDR-TB. LPA revealed 54 MTB positive among 57 MTB culture-positive samples and 3 showed invalid results. In LPA, MDR-TB was found in10 samples (17.54%) in which one was RIF-resistant. The study concludes risk factors that resulted in the development of TB are biomedical, socio-cultural, and behavioral interactions. LPA can be used as a rapid diagnostic technique for the detection of MDR-TB. Key words: Tuberculosis (TB), multidrug resistance (MDR-TB), drug susceptibility testing (DST), line probe assay (LPA). &nbsp

Rapid detection of multidrug-resistant tuberculosis based on allele-specific recombinase polymerase amplification and colorimetric detection.

Multidrug-resistant tuberculosis (MDR-TB) poses a serious threat to TB control. Early diagnosis and proper treatment are essential factors to limit the spread of the disease. The existing molecular tests for MDR-TB usually require specific instruments, steady power supply, and routine maintenance, which might be obstacles for low-resource settings. This study aimed to develop allele-specific isothermal recombinase polymerase amplification (allele-specific RPA) to simultaneously detect the most common mutations in the rpoB gene at codons 516, 526, and 531, which are associated with rifampicin resistance, and in the katG gene at codon 315, which is related to isoniazid resistance. Allele-specific primers targeting four major mutations, rpoB516, rpoB526, rpoB531, and katG315, were constructed and used in individual RPA reactions. The RPA amplicons were endpoints detected by the naked eye immediately after applying SYBR Green I. The optimised RPA assay was evaluated with the Mycobacterium tuberculosis wild-type strain H37Rv and 141 clinical M. tuberculosis isolates. The results revealed that allele-specific RPA combined with SYBR Green I detection (AS-RPA/SYBR) detected these four major mutations with 100% sensitivity and specificity relative to DNA sequencing. The limits of detection for these particular mutations with AS-RPA/SYBR were 5 ng. As a result of the outstanding performance of AS-RPA/SYBR, including its easy setup, speed, lack of a specific instrument requirement, and lack of cross-reaction with other bacteria, this technique may be integrated for the molecular diagnosis of MDR-TB, especially in low-resource settings.

A rapid and low-cost microscopic observation drug susceptibility assay for detecting TB and MDR-TB among individuals infected by HIV in South India

Background: The converging epidemics of HIV and tuberculosis (TB) pose one of the greatest public health challenges of our time. Rapid diagnosis of TB is essential in view of its infectious nature, high burden of cases, and emergence of drug resistance. Objective: The purpose of this present study was to evaluate the feasibility of implementing the microscopic observation drug susceptibility (MODS) assay, a novel assay for the diagnosis of TB and multi-drug-resistant tuberculosis (MDR-TB) directly from sputum specimens, in the Indian setting. Materials and Methods: This study involved a cross-sectional, blinded assessment of the MODS assay on 1036 suspected cases of pulmonary TB in HIV-positive and HIV-negative patients against the radiometric method, BD-BACTEC TB 460 system. Results: Overall, the sensitivity, specificity, positive predictive value, and negative predictive value of the MODS assay in detecting MTB among TB suspected patients were 89.1%, 99.1%, 94.2%, 95.8%, respectively. In addition, in the diagnosis of drug-resistant TB, the MODS assay was 84.2% sensitive for those specimens reporting MDR, 87% sensitivity for those specimens reporting INH mono-resistance, and 100% sensitive for specimens reporting RIF mono-resistance. The median time to detection of TB in the MODS assay versus BACTEC was 9 versus 21 days (P < 0.001). Conclusion: Costing 5 to 10 times lesser than the automated culture methods, the MODS assay has the potential clinical utility as a simple and rapid method. It could be effectively used as an alternative method for diagnosing TB and detection of MDR-TB in a timely and affordable way in resource-limited settings.

Evaluation of the frequency of mutation genes in multidrug-resistant tuberculosis (MDR-TB) strains in Beijing, China

The aim of this study was to explore the frequency and distribution of gene mutations that are related to isoniazid (INH) and rifampin (RIF)-resistance in the strains of the multidrug-resistant tuberculosis (MDR-TB) Mycobacterium tuberculosis (M.tb) in Beijing, China. In this retrospective study, the genotypes of 173 MDR-TB strains were analysed by spoligotyping. The katG, inhA genes and the promoter region of inhA, in which genetic mutations confer INH resistance; and the rpoB gene, in which genetic mutations confer RIF resistance, were sequenced. The percentage of resistance-associated nucleotide alterations among the strains of different genotypes was also analysed. In total, 90.8% (157/173) of the MDR strains belonged to the Beijing genotype. Population characteristics were not significantly different among the strains of different genotypes. In total, 50.3% (87/173) strains had mutations at codon S315T of katG; 16.8% (29/173) of strains had mutations in the inhA promoter region; of them, 5.5% (15/173) had point mutations at -15 base (C→T) of the inhA promoter region. In total, 86.7% (150/173) strains had mutations at rpoB gene; of them, 40% (69/173) strains had mutations at codon S531L of rpoB. The frequency of mutations was not significantly higher in Beijing genotypic MDR strains than in non-Beijing genotypes. Beijing genotypic MDR-TB strains were spreading in Beijing and present a major challenge to TB control in this region. A high prevalence of katG Ser315Thr, inhA promoter region (-15C→T) and rpoB (S531L) mutations was observed. Molecular diagnostics based on gene mutations was a useful method for rapid detection of MDR-TB in Beijing, China.

Drug-resistance of MDR-TB in Xi'an between 2018 and 2020 and the impact of COVID-19 epidemic prevention and control on it

Objective: To understand the epidemic status of drug-resistant Mycobacteriun tuberculosis in Xi'an in the past three years, and the impact of COVID-19 epidemic during 2020 so as to provide basic information for local multidrug-resistant tuberculosis (MDR-TB) prevention and treatment. Methods: Tuberculosis (TB) detected by sputum culture, the corresponding drug susceptibility tests data, and basic clinical information of TB patients diagnosed in Xi'an from January 2018 to October 2020 were collected from the management system;then the epidemic status and the drug resistance status were analyzed. Multinomial logistic regression was used to analyze the relationship between the patients' treatment history and the drug resistance of TB strains, and the trend of changes in the drug resistance rate in retreated patients. Results: In the past three years, there was a total drug resistance rate of 25.3% in 5 146 strains of MTB, and 24.8% in treatment initiation and 38.22% in retreatment, respectively. The treatment initiation patients showed a decreased MDR-TB detection rate, and the retreated patients had an increased MDR-TB detection rate. The spectrum of MDR-TB in the retreated patients gradually became more complicated, and the resistance rate of second-line drugs such as Kanamycin and Ofloxacin gradually increased. There were 10 drug-resistant combinations mainly in H+R+S and H+R+S+E. During the year 2020 of COVID-19 epidemic, the number of initial and retreated patients decreased significantly compared with that in 2018 and 2019, but with no difference in the drug-resistance rate. There was an increasing detection rate of PDR and MDR-TB strains in the retreated patients. Multinomial logistic regression results showed that in 2020 the retreated patients had 4.28 times of developing PDR-TB (P=0.001, 95% CI=1.417-12.930), and 5.378 times of developing MDR-TB (P< 0.001, 95% CI=2.641-10.952) than patients of treatment initiation. Conclusion: In the past three years, the prevention and control of drug-resistant TB in Xi'an has achieved some progress, but drug resistance in retreated patients is still serious. To avoid and reduce the development of drug-resistant TB, precise and active intervention measures should be taken, and health management of TB patients should be strengthened, especially during the current period of COVID-19 epidemic prevention and control. © 2021, Editorial Board of Journal of Xi'an Jiaotong University (Medical Sciences). All right reserved.

Rapid molecular assay gene Xpert in detection of multi-drug resistant tuberculosis (MTB/Rif)

Background: Tuberculosis (TB) is one of the deadliest threats today; TB due to Mycobacterium tuberculosis (MTB) remains a major public health issue: the infection affects up to one third of the world population, and almost two million people are killed by TB each year. However, in many areas of the world, TB diagnosis still relies on insensitive, poorly standardized sputum microscopy methods. Antibiotic resistance is a growing problem with increasing rate of drug-resistant tuberculosis (MDRTB) which is a serious public health problem in many developing countries. Treatment of MDTB takes longer and requires more expensive drugs. GeneXpert assay is a molecular technique that simultaneously detects (MTB) and Rifampicin resistant Tuberculosis (RR-TB) in approximately 2 h. Methods and materials: A retrospective cross sectional review of patients screened for TB with GeneXpert assay at TB Reference Laboratory,Khartoum State,Sudan from 20th June 2017 and 30th November 2017 (n = 583). Data analysis was done using Epi-Info Software, version 7.2 and Microsoft Office Excel 2007. Results: The total number of specimens collected from patients with symptoms of pulmonary TB was 583 (Males 402/Females 181). One hundred and fifty nine (159) (27.3%) of the screened samples had positive results for MTB, (Males 123/Females 36) of which 63 has history of past TB treatment, 71 New and 25 has un known past history of TB treatment. Among the positive MTB there is one case positive for HIV. Out of 159 there were 26 (4.4%) had rifampicin resistant MDR TB (22 males/4 females), all of MDR TB were more than 14 years, 16 has previous treatment of TB, 9 new and 1 has un known history of TB treatment. The male patients were more resistant to rifampicin when compared to the female patients.MTB was not detected in 424 (279 males 145 females). These despite the usefulness of GeneXpert assay method in early MTB/MDRTB diagnosis. Conclusion: Its simplicity, high sensitivity and specificity for RIF resistance detection make this technique a attractive tool for diagnostic of MTB and RIF resistance in MDR suspects.

The Role of IL-6 Gene Polymorphism in Multidrug-Resistant Tuberculosis Patients in Iraq

Background: Tuberculosis (TB) remains to be a leading cause of morbidity and mortality in developing countries, and the incidence of the disease is increasing in developed. One-third of the world’s population is infected by Mycobacterium tuberculosis (Mtb). Still, only about 5% of infected individuals develop the disease within the first year of infection, and another 5% develop the disease later in life. Aim of the study: Is to investigate the relationship between the levels of Interleukin 6 (IL-6) and detection of multidrug-resistant tuberculosis (MDR-TB) in Al-Diwaniyah population. Patients and methods: The current study included 120 patients with tuberculosis who were classified into two groups. The first group included 60 TB patients who were sensitive to anti TB drugs and 60 patients with multi-drug resistance (MDR) based on gene Xpert. The study also included 60 healthy individuals serving as a control group. Demographic characteristics of study and control groups were retrieved. IL-6 (-572G/C) genotype polymorphism was carried out using polymerase chain reaction (PCR) and according to the instruction of the providing company. Serum level of IL-6 was also measured by ELISA according to the instruction of the providing company. Results: It has been observed that genotype CC was more frequent in sensitive TB patients than both MDR TB patients and control subjects, 73.3 % versus 60 % and 61.7 %, respectively. Serum IL-6 level was significantly higher in MDR TB patients than in control group (p = 0.007), and there was no significant difference in its level between sensitive and MDR TB patients (p = 0.284). Conclusion: IL-6 gene polymorphism is not associated with multidrug resistance in TB patients; however, Serum IL-6 level was significantly higher in MDR TB patients than in the control group.

A pilot study: VereMTB detection kit for rapid detection of multidrug-resistant mycobcterium tuberculosis in clinical sputum samples.

The performance of VereMTBTM Detection Kit for detection of multidrug-resistant tuberculosis (MDR-TB) was validated by using 124 sputum samples. Comparing with MGIT culture, the sensitivity and specificity of VereMTB Detection Kit for MTBC detection were 97.0% and 98.3%, respectively. Compared with MGIT DST, the sensitivity and specificity of VereMTB Detection Kit for RIF resistance detection were 85.7% and 93.9%, respectively, and the sensitivity and specificity of VereMTB Detection Kit for INH resistance detection were 75.0% and 95.7%, respectively. 6 NTM samples were also detected and identified correctly. The VereMTB Detection Kit can detect MDR-TB rapidly and accurately in sputum samples from TB suspects.

Challenge of the Rising Multidrug-Resistant Tuberculosis in China: A Predictive Study Using Markov Modeling

Background: Multidrug-resistant tuberculosis (MDR-TB) is emerging in China. We used a dynamic Markov model to predict the longitudinal trends of MDR-TB in China by 2050, and assess the effects of alternative control measures. Methods Eight states of TB transmission were set up in the Markov model using a hypothetical cohort of 100,000 people. Prevalence of MDR-TB and bacteriological confirmed drug-susceptible TB (DS-TB+) were simulated. MDR-TB was stratified into being treated with the recommended regimen or not. Findings: Under the current China’s TB control conditions, by 2050, prevalence of DS-TB+ could be estimated to decrease to 39 per 100,000 people, a 37·1% reduction from 2019 , whereas MDR-TB would increase by three times to 58/100,000. Furthermore, by the year of 2050, 86·2% of the MDR-TB cases would be left untreated. If the detection rate of MDR-TB could reach 50% or 70% at 5% per year, the decline of MDR-TB prevalence would be 25·9% and 36·2% respectively. If treatment coverage was improved to 70% or 100% by 5% yearly , MDR-TB prevalence in 2050 would gain a reduction of 13·8% and 24·1%, respectively. If both detection rate and treatment coverage could reach 70%, the prevalence of MDR-TB would be reduced to 28/100, 000, a 51·7% reduction by 2050. Interpretation: MDR-TB, especially untreated MDR-TB, would rise rapidly under current MDR-TB control strategies in China. Interventions on promoting effective detection and treatment of MDR-TB are imperative in the fights against MDR-TB epidemics. Funding Statement: The Sweden-China (VR-NSFC) joint project (PI, Biao Xu, 81361138019 and Sven Hoffner, 540-2013-8797). Declaration of Interests: The authors stated: None declared. Ethics Approval Statement: Not required.

Prevalence of Multidrug-Resistant Tuberculosis at a Regional Drug-Resistant Tuberculosis Center of Maharashtra

Introduction: Multidrug-resistant tuberculosis (MDR-TB) has created a significant health problem in most of the countries, and it is an obstacle to effective TB control. Aims and Objectives: The study aims to study the prevalence of MDR-TB among new cases, retreatment cases and to study the rate of MDR-TB detection among suspected cases of Category I (CAT I) failure, CAT II failure and at the start of CAT II. Patients and Methods: The present retrolective study was conducted by reviewing the records of diagnosed MDR-TB patients at a drug-resistant TB center from January 2012 to December 2013. The data of new and retreatment pulmonary TB (PTB) cases diagnosed during that period were collected. The data were analyzed to find out the prevalence of MDR-TB, and the rate of MDR-TB detected among each CAT. Results: The prevalence of MDR-TB in new cases was 0.10% and that of retreatment cases was 4.3%. The rate of MDR-TB detection among suspected cases of CAT I failure was 16.8%, 52.4% in CAT II failure, 11.6% at the start of CAT II, 11.7% among sputum positive during any month follow-up, 6.6% among MDR-TB contacts. Conclusion: Timely suspicion and diagnosis of MDR-TB and treatment are important in new and retreatment cases. All relapse or defaulter patients should be screened for MDR-TB at the start of CAT II treatment. MDR-TB should be suspected in any sputum-positive TB patient during treatment/sputum positive relapse/defaulter PTB.

Detection of Multi-Drug Resistance Tuberculosis by Line Probe Assay Method

Detection of Multi-Drug Resistance Tuberculosis by Line Probe Assay Method

Early Detection of Multi-drug Resistant Tuberculosis and Mutations in Mycobacterium tuberculosis Isolates using Line Probe Assay from a Tertiary Care Centre in Northern India

Early Detection of Multi-drug Resistant Tuberculosis and Mutations in Mycobacterium tuberculosis Isolates using Line Probe Assay from a Tertiary Care Centre in Northern India

Mycobacterium tuberculosis burden, multidrug resistance pattern, and associated risk factors among presumptive extrapulmonary tuberculosis cases at Dessie Referral Hospital, Northeast Ethiopia

Background Tuberculosis (TB) represents one of the major challenges to global health. TB is usually classified based on the disease symptoms and the site of infection. Two types of clinical manifestation of TB are pulmonary tuberculosis (PTB) and extrapulmonary tuberculosis (EPTB). Objective This study aimed at determining Mycobacterium tuberculosis and multidrug-resistant tuberculosis (MDR-TB) burden among presumptive EPTB cases and associated risk factors at Dessie Referral Hospital, North West Ethiopia. Methods A cross-sectional study was conducted from February to April, 2018. A total of 337 presumptive EPTB cases in Dessie Referral Hospital were included using convenient sampling. Data were collected using a prestructured questionnaire. Body fluid specimens were collected and processed. Cytology, GeneXpert, and GenoType MTBDR plus Line Probe Assays were used for the detection of MTB and MDR-TB. Data were entered and cleared by Epi data version 3.1 and analyzed using SPSS, version 21. Multivariate analysis was done. P value less than 0.05 at 95% confidence interval was considered as statistically significant. Results The overall prevalence of EBTB using GeneXpert and cytopathological technique was 23.4, 27.3%, respectively. TB lymphadenitis (48 and 53.3%, respectively) was the dominant type followed by pleural (27 and 25%, respectively) and peritoneal (24% and 21.7%, respectively) by GeneXpert and cytology. The prevalence of MDR-TB was one (1.3%). Previous history of PTB (P Conclusion High prevalence of EPTB (27.3%) was reported, and 1.3% of them were MDR-TB. TB lymphadenitis was dominant. History of previous PTB and HIV was significantly associated with EPTB. Therefore, clinicians, public health professionals, and health programmers should give attention to EPTB case finding, treatment as well as prevention and control of EPTB by adhering guidelines of the ministry of health and WHO recommendations.

Line probe assay, a rapid and efficient test for the diagnosis of multidrug-resistant tuberculosis in Egypt

Background Earlier detection of tuberculosis (TB) and multidrug-resistant tuberculosis (MDR-TB) is crucial to preclude TB. We examined a genotypic drug sensitivity testing method for drug-resistant TB diagnosis using the line probe method as a rapid and technically simple method. The test used mutation-specific probes to determine isoniazid (INH) and rifampin resistance (RIF). Patients and methods The study was carried out on 82 Mycobacterium tuberculosis isolates that were identified phenotypically as MDR-TB isolates. The GenoBlot assay was assessed for fast detection of both rifampicin (RIF) and INH resistance against conventional phenotypic anti-TB drug sensitivity testing. The results were contrasted with the phenotypic drug susceptibility testing (DST) results of targeted samples; the turnaround time for both methods was evaluated. Results Compared with classical DST on solid media (Lowenstein Jensen), the line probe assay (LPA) technique had a relatively high concordance rate. The sensitivity to rifampicin was 94 and 91.5% for INH, and both showed 100% specificity. The consumed time for results by LPA was 24–48 h, while required 26 days for phenotypic culture on solid media and a supplemental 44 days for phenotypic DST. Conclusion LPA is a rapid, sensitive, easy to use, and efficient genotypic DST for MDR-TB detection.