Multidrug-resistant Tuberculosis Cases Research Articles

Genetic diversity and transmission pattern of multidrug-resistant tuberculosis based on whole-genome sequencing in Wuhan, China

BackgroundInvestigating the molecular epidemiological characteristics of multidrug-resistant tuberculosis (MDR-TB) in China’s moderate-burden regions, such as Wuhan, is crucial for understanding and controlling disease transmission.Materials and methodsThis study analyzed MDR-TB isolates from pulmonary tuberculosis cases registered at Wuhan Pulmonary Hospital in 2017. Whole genome sequencing (WGS) was used to identify resistance-conferring mutations, examine their associations with specific Mycobacterium tuberculosis lineages or sublineages, and assess clustering profiles.ResultsAmong the 149 analyzed strains, the most prevalent mutations associated with resistance to 11 anti-tuberculosis drugs were identified as follows: rpoB Ser450Leu (59.73%, rifampicin), katG Ser315Thr (62.42%, isoniazid), embB Met306Val (42.86%, ethambutol), rpsL Lys43Arg (68.13%, streptomycin), pncA Trp68Arg (10.53%, pyrazinamide), gyrA Asp94Gly (22.50%, fluoroquinolones), and rrs 1401A > G (50.00–100.00%, second-line injectable aminoglycosides). Additional mutations were detected in fabG1 c-15C > T (42.86%, ethionamide) and thyX c-16C > T (21.43%, p-aminosalicylic acid). Notably, rare mutations absent from the WHO mutation catalog, such as ahpC c-52C > T and rpsL Lys43Thr, were also observed. The mutation frequency of embB Met306Ile was significantly higher in Lineage 4 (L4) strains than in Lineage 2 (L2) strains (p = 0.0150), while the rpsL Lys43Arg mutation frequency was lower in L4 compared to L2 (p = 0.0333). A total of 31 MDR MTB Mycobacterium tuberculosis isolates formed clusters, resulting in a clustering rate of 20.81% and a recent transmission rate of 11.41%. The clustering rates between L4 and L2 strains were not significantly different (χ2 = 0.0017, p > 0.05).ConclusionThe genetic diversity of MDR-TB in Wuhan demonstrates unique characteristics, with evidence of localized transmission. These findings highlight the urgent need to strengthen measures to detect early cases of MDR-TB and control transmission of MDR-TB in the region.

Effect of COVID-19 restriction measures on multidrug resistant tuberculosis case notifications and treatment outcomes at treatment centres in Uganda

BackgroundMultidrug resistant tuberculosis (MDR-TB) is a global public health threat. In 2021, an incidence of 3.6% was reported among new TB patients, and 18% was reported among previously treated patients. The emergence of the COVID-19 pandemic impacted the health sector, although little is known about the effect of restrictive COVID-19 measures on MDR-TB case notifications and treatment outcomes in Uganda. This study aimed to assess the effect of COVID-19 restriction measures on MDR-TB case notifications and treatment outcomes at treatment centres in Uganda.MethodsThis was a retrospective cohort study in which a total of 483 participants were enrolled—238 before (March 2018-February 2020) and 245 during (March 2020-February 2022) COVID-19 restrictions. The data were extracted from the Drug-Resistant Tuberculosis (DR-TB) Health Management Information System (HMIS), and patient charts, and census sampling was employed. Interrupted time series (ITSA) was used to compare MDR-TB case notifications and treatment outcomes.ResultsBefore the COVID-19 restrictions, the majority 58.0% were aged less than or equal to 38 years whereas during the restrictions, the majority 51.8% were aged greater than 38 years. A total of 238 cases of MDRTB were reported before, and 245 cases were reported during the restrictions. There was no immediate (β2; 0.134) or sustained (β3; 0.494) impact of COVID-19 restriction measures on monthly MDR-TB case notifications. The mean number of monthly MDR-TB notifications was similar for the 3-month period before (11.0 cases per month) and during (10.0 cases per month) the COVID-19 restrictions (p-value 0.661). The proportions of patients who achieved successful MDR-TB treatment before (81.5%) and during (81.7%) COVID-19 restriction was not significantly different (p- value < 0.001). During the COVID-19 restrictions, not being married (aPR 0.85, 95% CI: 0.74—0.97) and treatment delay greater than 7 days (aPR 0.87, 95% CI 0.78—0.96) were negatively associated with successful treatment outcomes.ConclusionRestrictive COVID-19 measures did not affect MDR-TB case notifications or treatment outcomes. Not being married and having a treatment delay greater than 7 days reduced the chances of a successful treatment outcome during COVID-19. The WHO and MoH should continue strengthening active case finding, contact screening and community engagement to consolidate MDR-TB control and management in preparation for similar future pandemics.

Phenotypic drug resistance and genetic mutations linked to resistance among extrapulmonary tuberculosis patients in Ethiopia: Insights from Whole Genome Sequencing.

Globally, drug-resistant tuberculosis (DR-TB) is responsible for 13% of mortality attributable to antimicrobial resistance. In Ethiopia, extrapulmonary tuberculosis (EPTB) is a significant public health challenge, and drug resistance (DR) in EPTB is often overlooked. In a cross-sectional study conducted between August 2022 and October 2023, we aimed to explore the magnitude of phenotypic drug resistance and identify genetic mutations linked to resistance using 189 Mycobacterium tuberculosis (MTB) isolates cultured from extrapulmonary clinical specimens. Additionally, we assessed the agreement of the phenotypic and whole genome sequencing (WGS) based genotypic drug resistance detection. We performed phenotypic drug sensitivity testing (pDST) using liquid culture BD BACTECTM MGITTM 960 system and WGS using Illumina NextSeq500/550. The genomic data analysis pipelines MTBSeq and TBProfiler were used to predict drug resistance-conferring mutations. The agreement between the pDST and WGS was analyzed using SPSS version 29.0 software. Our result demonstrated phenotypic resistance to at least one anti-TB drug was detected in 16.9% (32/189) of the study participants. Isoniazid-resistant rifampicin-susceptible-TB (Hr-TB) and multi-drug-resistant TB (MDR-TB) phenotypes accounted for 2.6% (5/189) and 4.2% (8/189) respectively. Prevalence of MDR-TB was 2.4% (4/170) among newly diagnosed and 21.1% (4/19) among previously treated cases. WGS identified more (14/160, 8.75%) rifampicin-resistant genotypes (RR-TB) compared to pDST (8/189, 4.2%). We have identified a putative compensatory mutation for rifampicin (rpoBSer450Leu, rpoCAsp747Ala) for the first time from an EPTB clinical specimen in Ethiopia. Overall, there was a 3.75% rifampicin mono-resistant-TB(RMR-TB) genotype, which remains undetected using the conventional pDST and represented 42.9% (6/14) of the identified RR-TB genotypes. Mutations conferring rifampicin resistance-interim (rpoB.Ser450Ala) represented the majority (83.3%) of RMR-TB. Changes in ethA genes associated with ethionamide resistance were the most common resistance (n=7, 87.5%) in MDR-TB cases. There was a strong agreement between the pDST and WGS-TB Profiler pipeline to detect RR-TB (kappa=0.8) compared to the MTBSeq pipeline (k=0.58). In conclusion, MDR-TB, Hr-TB, and interim-RMR-TB are equally important public health challenges in the realm of EPTB in Ethiopia. The role of WGS is tremendous in detecting borderline/interim RMR-TB, which will help for tailored, personalized treatment strategies.

Multidrug-resistant tuberculosis treatment outcomes and associated factors at Yirgalem General Hospital, Sidama Region, South Ethiopia: a retrospective cohort study

BackgroundThe spread of multidrug-resistant tuberculosis (MDR-TB) poses a significant challenge to TB control efforts. This study evaluated the treatment outcomes and associated factors among patients receiving treatment for MDR-TB in southern Ethiopia.MethodsA retrospective follow-up study covering ten years, from 2014 to 2023, analyzed the records of confirmed cases of pulmonary TB admitted to Yirgalem General Hospital, an MDR-TB treatment initiation center in the Sidama Region. To compare the successful treatment outcomes across the years, a chi-square test of independence was conducted. Bivariate and multivariable logistic regression models were used to identify factors associated with treatment outcomes for MDR-TB.ResultsOut of 276 confirmed MDR-TB cases, 4(1.4%) were diagnosed with resistance to second-line drugs (SLDs). Overall, 138 patients achieved favourable treatment outcomes, resulting in a treatment success rate of 50.0% [95% CI 44.1–55.9%]. Among these 138 patients, 105(76.1%, 95 CI 68.7–83.5%) were cured, while 33(23.9%, 95 CI 16.5–31.3%) completed their treatment. The successful treatment outcomes varied significantly across the years, ranging from 3.6% in 2020 to 90% in 2021. The analysis indicated a statistically significant difference in treatment outcomes when considering data from 2014 to 2023 (χ2 = 44.539, p = 0.001). The proportion of patients with deaths, lost-to-follow-up (LTFU), treatment failures and not evaluated were 7.9% [95% CI 4.8–11.2%], 10.9% [95% CI 7.2–14.6%), 2.2% [95% CI 1.1–3.3%), and 28.9% [95% CI 23.7–34.2%] respectively. Individuals with a positive HIV status had significantly lower odds of a favorable treatment outcome [AOR = 0.628, 95% CI (0.479–0.824), p = 0.018]. Similarly, patients with a BMI of less than 18 are more likely to have unfavorable treatment outcomes compared to those with a BMI of 18 or higher [AOR = 2.353, 95% CI 1.404–3.942, p < 0.001].ConclusionThe study revealed a concerning 1.4% prevalence of additional resistance to SLDs. The 50% rate of unfavorable treatment among MDR-TB cases exceeds the target set by the WHO. A significant number of patients (10.9%) were LTFU, and the 28.9% categorized as ‘not evaluated’ is also concerning. Enhanced strategic interventions are needed to reduce such cases, and factors associated with poor treatment outcomes should receive greater attention. Future prospective studies can further explore the factors influencing improved treatment success.

Prevalence and epidemic pattern of ecdemic multidrug-resistant tuberculosis during 2012–2022 in Hangzhou, China: implication for public health strategies

BackgroundTo assess the prevalence and epidemic pattern of multidrug-resistant tuberculosis in Hangzhou City, Zhejiang Province, China during 2012–2022.MethodsAll the tuberculosis cases undergoing drug susceptibility testing during 2012–2022 were included in this study. De-identified information was extracted from the electronic database Tuberculosis Information Management System for analysis of drug resistance prevalence in Hangzhou and ecdemic multidrug-resistant tuberculosis which originated from other regions. Chi-square tests were used to compare drug resistance rates between different groups, while Chi-square tests for trend were used to evaluate the change of drug resistance rates over the years of 2012–2022. The sources and destinations of ecdemic multidrug-resistant tuberculosis were illustrated using a Sankey diagram.ResultsOf 21,127 cases included in this study, 1119 (5.3%) were multidrug-resistant tuberculosis. A significant decline in multidrug-resistant tuberculosis rates was observed during 2012–2022. There was a significant difference in multidrug-resistant tuberculosis rates among immigrant population and local residents in Hangzhou City. Of 1119 multidrug-resistant tuberculosis cases, 515(46%) were ecdemic multidrug-resistant tuberculosis cases, of which 277(53.8%) were from other parts of Zhejiang Province and 238(46.2%) were from other provinces in China. Anhui, Jiangxi and Sichuan were among top three provinces which were the source of ecdemic multidrug-resistant tuberculosis cases. Three districts including Xiaoshan, Shangcheng and Linping districts had the most cases in Hangzhou. The proportion of ecdemic multidrug-resistant tuberculosis cases in Binjiang, Xiaoshan, Qiantang and Linping districtalso exceeded 30% of total cases.ConclusionsMultidrug-resistant tuberculosis prevalence has been declining in Hangzhou. Migrant population contributed to a significant potion of cases in Hangzhou. Interventions should be tailed to local and migrant residents.

MOLECULAR GENETIC CHARACTERISTICS OF MYCOBACTERIUM TUBERCULOSIS ISOLATES CIRCULATING IN ASTANA

According to the World Health Organization, Kazakhstan takes a leading position in the number of cases of multidrug-resistant tuberculosis. This work is aimed at studying clinical isolates of Mycobacterium tuberculosis circulating in Astana in 2021–2022. Among 198 M. tuberculosis isolates collected, 175 (88.38%) belonged to the L2/Beijing family, and the remaining 23 samples (11.62%) belonged to the L4 family. During the research used genotyping aimed at determining the genetic family of M. tuberculosis, as well as whole-genome sequencing of selected 24 L2/Beijing isolates with their subsequent bioinformatics analysis. According to the analysis results, 62.5% of isolates were assigned to the Central Asia Outbreak genotype. The remaining genotypes were represented by Central Asia (20.8%), B0/W148 (12.5%) and Clade A (4.2%). Besides that, phenotypic and genotypic characterization of the resistance of selected isolates to anti-tuberculosis drugs was carried out. One of the possible reasons for the spread of resistant forms of tuberculosis in the country is the predominance of the Central Asia Outbreak genetic cluster associated with MDR-TB.

To investigate the impact of revised diagnostic algorithm on presentation of multidrug-resistant tuberculosis cases at a referral centre in India

ABSTRACT Introduction: A shift in policy has occurred with the introduction of molecular diagnostic tools for the upfront diagnosis of all cases of tuberculosis, including drug-resistant tuberculosis. The impact of this shift in policy on severity of disease was studied, and comparisons were drawn between the year 2015 and 2020. Study Type and Design: This was an observational study conducted between 2020 and 2021. Seventy patients of MDR-TB with or without additional drug resistance, hospitalized in the year 2015 and 2020, were studied. Results: The study reveals a substantial reduction in the median time from the onset of symptoms to diagnosis between 2015 and 2020. Specifically, the median duration decreased from 12 weeks in 2015 to 8 weeks in 2020. Moreover, we found that in 2015, all cases under study had a history of tuberculosis in comparison to 2020. Additionally, there was a higher incidence of anemia in 2015 compared to 2020. In the radiological examination, it was observed that in 2015, a higher frequency of cases exhibited cavitations, bronchiectasis, and fibrosis on chest X-rays compared to the findings in 2020. The mean cavity size in 2015 measured 6.73 cm, while in 2020, it averaged 4.06 cm. Additionally, we noticed a higher occurrence of significantly advanced cases in 2015 in contrast to 2020. Conclusion: The implementation of the new policy of upfront DST was noted to decrease the time required for diagnosis and bacterial load as ascertained from degree of sputum smear positivity, radiological lesions, and severity of anemia.

Clinical Profiles of Multidrug-Resistant and Rifampicin-Monoresistant Tuberculosis in Korea, 2018-2021: A Nationwide Cross-Sectional Study.

This study aimed to identify the clinical characteristics of multidrug-resistant/ rifampicin-resistant tuberculosis (MDR/RR-TB) in the Republic of Korea. Data of notified people with tuberculosis between July 2018 and December 2021 were retrieved from the Korea Tuberculosis Cohort database. MDR/RR-TB was further categorized according to isoniazid susceptibility as follows: multidrug-resistant tuberculosis (MDR-TB), rifampicin-monoresistant tuberculosis (RMR-TB), and RR-TB if susceptibility to isoniazid was unknown. Multivariable logistic regression analysis was conducted to identify the factors associated with MDR/RR-TB. Between 2018 and 2021, the proportion of MDR/RR-TB cases among all TB cases and TB cases with known drug susceptibility test results was 2.1% (502/24,447). The proportions of MDR/RR-TB and MDR-TB cases among TB cases with known drug susceptibility test results were 3.3% (502/15,071) and 1.9% (292/15,071), respectively. Among all cases of rifampicin resistance, 31.7% (159/502) were RMR-TB and 10.2% (51/502) were RR-TB. Multivariable logistic regression analyses revealed that younger age, foreigners, and prior tuberculosis history were significantly associated with MDR/ RR-TB. Rapid identification of rifampicin resistance targeting the high-risk populations, such as younger generations, foreign-born individuals, and previously treated patients are necessary for patient-centered care.

Multidrug-resistant tuberculosis clusters and transmission in Taiwan: a population-based cohort study.

Multidrug-resistant tuberculosis (MDR-TB) remains a challenge in the TB program of Taiwan, where 0.5% of new cases and 2.1% of previously treated cases were resistant to at least rifampin (RIF) and isoniazid (INH). Since >80% of our MDR-TB are new cases, genotyping of MDR Mycobacterium tuberculosis is implemented to facilitate contact investigation, cluster identification, and outbreak delineation. This is a population-based retrospective cohort study analyzing MDR-TB cases from 2019 to 2022. Whole genome sequencing (WGS) was performed using the Illumina MiSeq and analyzed using the TB Profiler. A single nucleotide polymorphism (SNP) threshold of ≤ 12 and phylogenetic methods were used to identify putative transmission clusters. An outbreak was confirmed using genomic data and epidemiologic links. Of the 297 MDR-TB cases, 246 (82.8%), 45 (15.2%), and 6 (2.0%) were simple MDR, extensively drug-resistant tuberculosis (pre-XDR-TB) and extensively drug-resistant tuberculosis (XDR-TB), respectively. The sublineage 2.2 modern Beijing was the predominant (48.8%) MDR-TB strain in Taiwan. Phylogenetic analysis identified 25.3% isolates in 20 clusters, with cluster sizes ranging from 2 to 13 isolates. Nevertheless, only 2 clusters, one household and one community, were confirmed as outbreaks. In this study, we found that males had a higher risk of MDR-TB transmission compared to females, and those infected with the sublineage 2.1-proto-Beijing genotype isolates were at a higher risk of transmission. Furthermore, 161 (54.2%) isolates harbored compensatory mutations in the rpoC and non-rifampicin resistant determinant region (non-RRDR) of the rpoB gene. MDR-TB strains containing rpoB S450L and other compensatory mutations concurrently were significantly associated with clusters, especially the proto-Beijing genotype strains with the compensatory mutation rpoC E750D or the modern Beijing genotype strains with rpoC D485Y/rpoC E1140D. Routine and continuous surveillance using WGS-based analysis is recommended to warn of risks and delineate transmission clusters of MDR-TB. We proposed the use of compensatory mutations as epidemiological markers of M. tuberculosis to interrupt putative MDR-TB transmission.

Burden of drug-resistant tuberculosis by the GeneXpert MTB/RIF assay and its clinico-epidemiological aspects at a tertiary care hospital in West Bengal

Multidrug -resistant tuberculosis (MDRTB) is a serious threat to mankind. India has the highest number of MDRTB cases, although majority remain undiagnosed due to inadequate diagnostic infrastructure, leading to increased community transmission and mortality. This one-year observational retrospective study highlighted the effectiveness of the National Tuberculosis Elimination Program (NTEP) for prompt detection of drug-resistant TB by GeneXpert MTB/RIF assay and revealed its associated clinico-epidemiological factors. The overall detection rates of MTB and RRTB were 20.70 % and 20.86 % respectively. The pediatric population had 7.69 % rifampicin resistance, and HIV was strongly associated with the development of TB and RRTB (P < 0.01).

An Overview of the Management of Drug-Resistant Tuberculosis in Six French-Speaking African Countries from 2018 to 2022.

Drug-resistant tuberculosis (DR-TB) poses a significant public health challenge, particularly in resource-limited settings. The prevalence and management of DR-TB in African countries require comprehensive strategies to improve patient outcomes and control the spread of the disease. Aggregated routine data (from 2018 to 2022) on multidrug-resistant TB (MDR-TB) were collected from the National TB Programs (NTPs) from all six countries. The diagnostic capacity for MDR-TB was globally insufficient. The system for collecting and transporting samples was sometimes inoperative. A total of 2353 cases of MDR-TB were reported, with 86.4% receiving treatment. The gap between the expected number of MDR-TB cases and the number reported per country varied from 51.5% to 88.0%, depending on the year. Fifty-two extensively drug-resistant (XDR) TB cases received treatment regimens over five years, with variations across countries. All patients received free follow-up examinations, nutritional and financial support for travel expenses to the outpatient care and treatment centers. The MDR-TB treatment success rates for all regimens between 2018 and 2021 ranged from 44.4 to 90.9%, varying by country and year. The information system relied on primary tools, reporting tools, and digital solutions. Progress has been made in MDR-TB management; however, challenges persist, necessitating resources to enhance access to rapid molecular screening tests.

Changes in the incidence, clinical features and outcomes of tuberculosis during COVID-19 pandemic

BackgroundCOVID-19 pandemic has disrupted tuberculosis (TB) services in many countries, but the impacts on sites of involvement, drug susceptibility, smear positivity and clinical outcomes, and clinical outcomes of co-infection with influenza and COVID-19 remain unclear. MethodsDescriptive epidemiological study using episode-based and patient unique data of tuberculosis from Hospital Authority’s territory-wide electronic medical record database, comparing baseline (January 2015-December 2019) and COVID-19 period (January 2020-December 2022), followed by univariate and multivariate analyses. Effects of co-infection with influenza and COVID-19 were investigated. ResultsThe study included 10,473 episodes of laboratory-confirmed TB, with 6818 in baseline period and 3655 during COVID-19 period. During COVID-19 period, TB patients had a lower proportion of smear positivity (49.2 % vs 54.7 %, P < 0.001), and fewer cases of extrapulmonary TB (7.0 % vs 8.0 %, P = 0.078) and multidrug resistant TB (1.0 % vs 1.6 %, P = 0.020). Mortality was higher in TB patients with COVID-19 coinfection (OR 1.7, P = 0.003) and influenza coinfection (OR 2.6, P = 0.004). During COVID-19 period, there were higher rates of treatment delay (20.5 % vs 15.5 %, P < 0.001) and episodic death (15.1 % vs 13.3 %, P = 0.006). Factors associated with higher mortality included age ≥ 70 years (OR 7.24), treatment delay (OR 2.16), extrapulmonary TB (OR 2.13). smear positivity (OR 1.71) and Charlson comorbidity index score ≥ 3 (OR 1.37). Higher mortality was observed with co-infection by influenza (OR 1.18) and COVID-19 (OR 1.7). ConclusionsThe epidemiology and outcomes of TB were changed during COVID-19 period. Mortality was higher during COVID-19 period and with co-infection by influenza and COVID-19.

Accurate and affordable detection of rifampicin and isoniazid resistance in Tuberculosis sputum specimens by multiplex PCR-multiple probes melting analysis

BackgroundEscalating cases of multidrug-resistant tuberculosis (MDR-TB) pose a major challenge to global TB control efforts, necessitating innovative diagnostics to empower decentralized detection of gene mutations associated with resistance to rifampicin (RIF) and isoniazid (INH) in Mycobacterium tuberculosis (M. tuberculosis) in resource-constrained settings.MethodsCombining multiplex fluorescent PCR and Multiple Probes Melting Analysis, we identified mutations in the rpoB, katG, ahpC and inhA genes from sputum specimens. We first constructed a reference plasmid library comprising 40 prevalent mutations in the target genes’ resistance determining regions and promoters, serving as positive controls. Our assay utilizes a four-tube asymmetric PCR method with specifically designed molecular beacon probes, enabling simultaneous detection of all 40 mutations. We evaluated the assay’s effectiveness using DNA isolated from 50 clinically confirmed M. tuberculosis sputum specimens, comparing our results with those obtained from Sanger sequencing and retrospective validation involving bacteriological culture and phenotypic drug susceptibility testing (pDST). We also included the commercial Xpert MTB/RIF assay for accuracy comparison.ResultsOur data demonstrated remarkable sensitivity in detecting resistance to RIF and INH, achieving values of 93.33% and 95.24%, respectively, with a specificity of 100%. The concordance between our assay and pDST was 98.00%. Furthermore, the accuracy of our assay was comparable to both Sanger sequencing and the Xpert assay. Importantly, our assay boasts a 4.2-h turnaround time and costs only $10 per test, making it an optimal choice for peripheral healthcare settings.ConclusionThese findings highlight our assay’s potential as a promising tool for rapidly, accurately, and affordably detecting MDR-TB.

Molecular analysis of bedaquiline resistance and genetic variations in clinical isolates of multidrug and fluoroquinolones-resistant Mycobacterium tuberculosis

BackgroundMycobacterium tuberculosis developing resistance to anti-tubercular therapy leads to pioneering innovative treatment protocols featuring carefully curated combinations of potent medications. The aim of this study was to analyze the frequency and pattern of fluoroquinolone (FQ) resistant mutations among the first-line drug-resistant specimens. By employing an elective sampling strategy, we deliberately focused our investigation on a targeted subset of multidrug resistant (MDR) and FQ resistant (FQR) TB cases. MethodSputum samples from first-line drug-resistant patients were subjected to a GenoType MTBDRsl VER 2.0 assay to determine FQR. To investigate the effect of bedaquiline (BDQ) on these mutation-conferring genes (Rv0678, pepQ, and atpE), sanger sequencing was carried out on the MDR + FQR subset that was obtained. We have also conducted a computational analysis of the gene products of Rv0678 and pepQ with BDQ using molecular docking methods. ResultsEighty-three samples were observed to have FQR, and the majority of these specimens were associated with naïve and treatment failure cases. Among them, 64 isolates exhibited mutations in gyrA gene, while 19 isolates showed mutations in gyrB gene. The predominant occurrence of genetic variations, particularly in D94G and A90V, was observed within the specimens displaying resistance in gyrA gene, and the same has been confirmed by PCR-based detection. And the sequence analysis of BDQ genes among MDR + FQR subset indicated that the majority of the samples did not exhibit mutations in pepQ and atpE genes. However, only 2 samples were found to have the genetic variant G337A, which involves replacing the amino acid glutamic acid (E) at codon position 113 of Rv0678 gene with lysine (K). ConclusionsMost of the mutations were harbored in rpoB + katG + gyrA gene pattern. These findings pave the way for the development of databases and rapid diagnostic probes.

War related disruption of clinical tuberculosis services in Tigray, Ethiopia during the recent regional conflict: a mixed sequential method study

BackgroundMore than 70% of the health facilities in Tigray, northern Ethiopia, have been totally or partially destroyed by the recent war in the region. Diagnosis and management of tuberculosis were among many health services that suffered. In this study we assess the status of tuberculosis care in health facilities of Tigray during the recent war and compare it with the immediate pre-war state.MethodsUsing sequential mixed method, we analyzed and compared the availability of diagnostic services in 69 health facilities and the utilization of tuberculosis care in 50 of them immediately before the war (September-October 2020) and during the war (November-July 2021). TB focal persons in each selected health facility were interviewed to evaluate the status of diagnostic services. Patient service utilization was assessed using health facility registrations. We also compared the average monthly case detection rate of multidrug resistant tuberculosis in the region before and during the war. We computed summary statistics and performed comparisons using t-tests. Finally, existing challenges related to tuberculosis care in the region were explored via in-depth interviews. Two investigators openly coded and analyzed the qualitative data independently via thematic analysis.ResultsAmong the 69 health facilities randomly selected, the registers of 19 facilities were destroyed by the war; data from the remaining 50 facilities were included in the TB service utilization analysis. In the first month of the war (November 2021) the number of tuberculosis patients visiting health facilities fell 34%. Subsequently the visitation rate improved steadily, but not to pre-war rates. This reduction was significant in northwest, central and eastern zones. Tuberculosis care in rural areas was hit hardest. Prior to the war 60% of tuberculosis patients were served in rural clinics; this number dropped to an average of 17% during the war. Health facilities were systematically looted. Of the 69 institutions assessed, over 69% of the microscopes in health centers, 87.5% of the microscopes in primary hospitals, and 68% of the microscopes in general hospitals were stolen or damaged. Two GeneXpert nucleic acid amplification machines were also taken from general hospitals. Regarding drug resistant TB, the average number of multidrug resistant tuberculosis (MDR TB) cases detected per month was reduced by 41% during the war with p-value < 0.001. In-depth interviews with eight health care workers indicated that the main factors affecting tuberculosis care in the area were lack of security, health facility destruction, theft of essential equipment, and drug supply disruption.Conclusion and recommendationMany tuberculosis patients failed to visit health facilities during the war. There was substantial physical damage to health care facilities and systematic looting of diagnostic equipment. Restoring basic public services and revitalizing clinical care for tuberculosis need urgent consideration.

Tuberculosis in Poland in 2021.

To evaluate the main features of epidemiology of tuberculosis (TB) in 2021 in Poland and to compare with the situation in the European Union and European Economic Area (EU/EEA) countries. Analysis of case-based data on TB patients from National TB Register, data on anti-TB drug susceptibility in cases notified in 2021, data from Statistics Poland on deaths from tuberculosis in 2020, data from National Institute of Public Health NIH - National Research Institute (NIPH NIH - NRI) on HIV-positive subjects for whom TB was an AIDS-defining disease, data from the report "European Centre for Disease Prevention and Control, WHO Regional Office for Europe. Tuberculosis surveillance and monitoring in Europe 2022 - 2021 data. Copenhagen: WHO Regional Office for Europe and Stockholm: European Centre for Disease Prevention and Control; 2022." In 2021, 3704 TB cases were reported in Poland. The incidence rate was 9.7 cases per 100,000 with large variability between voivodeships from 5.4 to 12.6 per 100,000. A decrease in the incidence with respect to 2020 was found in 8 voivodeships, the most significant in lubuskie voivodship (42.6%). The number of all pulmonary tuberculosis cases was 3,553 i.e. 9.3 per 100,000. Pulmonary cases represented 95.9% of all TB cases. In 2021, 151 extrapulmonary TB cases were notified (4.1% of all TB cases). Pulmonary tuberculosis was bacteriologically confirmed in 2,970 cases (83.6% of all pulmonary TB cases, the incidence rate 7.8 per 100,000). The number of smear-positive pulmonary TB cases was 2,085 i.e. 5.5 per 100,000 (58.7% of all pulmonary TB cases). In 2021, there were 54 cases (25 of foreign origin) with multidrug resistant TB (MDR-TB) representing 1.9% of cases with known drug sensitivity. The incidence rates of tuberculosis were growing along with the age group from 0.6 per 100,000 among children (0-14 years) to 15.8 per 100,000 among subjects in the age group 45-64 years, the incidence rate in the age group ≥65 years was 11.7 per 100,000. There were 37 cases in children up to 14 years of age (1.0% of the total) and 51 cases in adolescents between 15 and 19 years of age - rates 0.6 and 2.8 per 100,000 respectively. In 2021, there were 2,690 cases of tuberculosis in men and 1,014 in women. The TB incidence in men - 14.6 per 100,000 was almost 3.0 times higher than among women - 5.1. The biggest difference in the TB incidence between the two sex groups occurred in persons aged 55-59 years, 30.5 vs. 6.6 and in age group 60 to 64 years, 26.0 vs. 5.7. In 2021, there were 132 patients of foreign origin among all cases of tuberculosis in Poland (3.6%). In 2020, TB was the cause of death for 474 people (mortality rate - 1.2 per 100,000). The incidence of tuberculosis in Poland in 2021 was 10.2% higher than in 2020. The percentage of tuberculosis cases with bacteriological confirmation was 82.6%, higher than the average in EU/EEA countries (72.0%). The percentage of MDR-TB cases was lower than the average in EU/EEA countries (1.9% vs. 3.8%). The highest incidence rates are found in Poland in the older age groups (in EU/EEA countries in people aged 25 to 44). The percentage of children up to 14 years of age among the total number of TB patients was 1.0%, the average in the EU/EEA countries was 3.5%. The incidence of tuberculosis in men was nearly three times higher than in women in Poland. The impact of migration on the epidemiological situation of tuberculosis in Poland in 2021 was smaller than in the EU/EEA countries (in Poland, the percentage of foreigners among all TB patients was 3.6 vs. 33.8% in the EU/EEA).

A Case of Multidrug-Resistant Tuberculosis in an Active Duty Military Health Care Worker.

Cases of active tuberculosis (TB) in the U.S. Military have fallen over the last century in large part due to improved screening and treatment options. The subset of multidrug-resistant TB (MDR-TB) is almost nonexistent within the U.S. Military. We present a case of MDR-TB in an active duty U.S. Military health care worker and discuss several considerations for treatment that may present challenges for U.S. Military medical practitioners. A 30-year-old active duty Soldier was referred to Army public health services after a bronchoscopy sample was positive for Mycobacterium tuberculosis complex. Sputum smears were negative for acid-fast bacilli, suggesting lower risk for community spread. One month after initiation of the standard 4-drug regimen for active TB, genetic susceptibility testing found the patient's M. tuberculosis isolate to be resistant to rifampin, isoniazid, and pyrazinamide. Contact investigation efforts among co-workers and family members fortunately found no new interferon-gamma release assay conversions. Coordination of public health assets to ensure a successful treatment regimen occurred across varied local, state, and federal agencies. Atypical medications required coordination with the FDA for procurement. An extensive surveillance plan for medication adverse effects was required. Finally, questions of public health authority versus patient autonomy arose requiring multidisciplinary input and ethical discussions.

In vitro and ex vivo activity of the fluoroquinolone DC-159a against mycobacteria.

Antimicrobial resistance is a global health problem. In 2021, it was estimated almost half a million of multidrug-resistant tuberculosis (MDR-TB) cases. Besides, non-tuberculous mycobacteria (NTM) are highly resistant to several drugs and the emergence of fluoroquinolone (FQ) resistant M. tuberculosis (Mtb) is also a global concern making treatments difficult and with variable outcome. The aim of this study was to evaluate the activity of the FQ, DC-159a, against Mtb and NTM and to explore the cross-resistance with the currently used FQs.A total of 12 pre-extensively drug-resistant (XDR) Mtb, 2 XDR, 36 fully drug susceptible strains and 41 NTM isolates were included to estimate the in vitro activity of DC-159a, moxifloxacin (MOX) and levofloxacin (LX), using minimal inhibitory and bactericidal concentration (MIC and MBC). The activity inside the human macrophages and pulmonary epithelial cells were also determined.DC-159a was active in vitro and ex vivo against mycobacteria. Besides, it was more active than MOX/LX. Moreover, no cross-resistance was evidenced between DC-159a and LX/MOX as DC-159a could inhibit Mtb and MAC strains that were already resistant to LX/MOX.DC-159a could be a possible candidate in new therapeutic regimens for MDR/ XDR-TB and mycobacterioses cases.

Trends of Drug-Resistant Tuberculosis in an Urban and a Rural Area in China: A 10-Year Population-Based Molecular Epidemiological Study.

Drug resistance is the critical determinant for appropriate tuberculosis (TB) treatment regimens and an important indicator of the local TB burden. We aimed to investigate and compare trends in TB drug resistance in the urban Songjiang District of Shanghai from 2011 to 2020, and the rural Wusheng County of Sichuan Province from 2009 to 2020, to assess the effectiveness of local TB control and treatment programs. Whole-genome sequencing data of Mycobacterium tuberculosis were used to predict drug-resistance profiles and identify genomic clusters. Clustered, retreated cases of drug-resistant TB with identical resistance mutations, as well as all new resistant cases, were defined as transmitted resistance. The Cochran-Armitage trend test was used to identify trends in the proportions. Differences between groups were tested using the Wilcoxon rank sum or chi-square tests. The annual proportions of rifampicin-resistant (RR), isoniazid-resistant (INH-R) and multidrug-resistant (MDR) TB cases did not change significantly in Songjiang. In Wusheng, however, the percentage of total TB cases that were RR decreased from 13.2% in 2009 to 3.7% in 2020, the INH-R cases decreased from 16.5% to 7.3%, and the MDR cases decreased from 10.7% to 3.7%. In retreated cases, the percentage of drug resistance decreased in both Songjiang and Wusheng, suggesting improved treatment programs. Transmitted resistance accounted for more than two thirds of drug-resistant cases over the entire study periods, and in recent years this proportion has increased significantly in Songjiang. In both urban Songjiang and rural Wusheng, drug-resistant TB is mostly the result of transmission of drug resistant strains and the percentage of transmitted resistance will likely increase with on-going improvements in the TB treatment programs. Reducing the prevalence of drug resistance depends principally upon decreasing transmission through the prompt diagnosis and effective treatment of drug-resistant TB cases.

Spatial Analysis of Drug-Susceptible and Multidrug-Resistant Cases of Tuberculosis, Ho Chi Minh City, Vietnam, 2020-2023.

We characterized the spatial distribution of drug-susceptible (DS) and multidrug-resistant (MDR) tuberculosis (TB) cases in Ho Chi Minh City, Vietnam, a major metropolis in southeastern Asia, and explored demographic and socioeconomic factors associated with local TB burden. Hot spots of DS and MDR TB incidence were observed in the central parts of Ho Chi Minh City, and substantial heterogeneity was observed across wards. Positive spatial autocorrelation was observed for both DS TB and MDR TB. Ward-level TB incidence was associated with HIV prevalence and the male proportion of the population. No ward-level demographic and socioeconomic indicators were associated with MDR TB case count relative to total TB case count. Our findings might inform spatially targeted TB control strategies and provide insights for generating hypotheses about the nature of the relationship between DS and MDR TB in Ho Chi Minh City and the wider southeastern region of Asia.