Mode of Action of Kanglemycin A, an Ansamycin Natural Product that Is Active against Rifampicin-Resistant Mycobacterium tuberculosis.

Antibiotic-resistant bacterial pathogens pose an urgent healthcare threat, prompting a demand for new medicines. We report the mode of action of the natural ansamycin antibiotic kanglemycin A (KglA). KglA binds bacterial RNA polymerase at the rifampicin-binding pocket but maintains potency against RNA polymerases containing rifampicin-resistant mutations. KglA has antibiotic activity against rifampicin-resistant Gram-positive bacteria and multidrug-resistant Mycobacterium tuberculosis (MDR-M. tuberculosis). The X-ray crystal structures of KglA with the Escherichia coli RNA polymerase holoenzyme and Thermus thermophilus RNA polymerase-promoter complex reveal an altered-compared with rifampicin-conformation of KglA within the rifampicin-binding pocket. Unique deoxysugar and succinate ansa bridge substituents make additional contacts with a separate, hydrophobic pocket of RNA polymerase and preclude the formation of initial dinucleotides, respectively. Previous ansa-chain modifications in the rifamycin series have proven unsuccessful. Thus, KglA represents a key starting point for the development of a new class of ansa-chain derivatized ansamycins to tackle rifampicin resistance.

Estimating Post-treatment Recurrence After Multidrug-Resistant Tuberculosis Treatment Among Patients With and Without Human Immunodeficiency Virus: The Impact of Assumptions About Death and Missing Follow-up.

BACKGROUND: Quantification of recurrence risk following successful treatment is crucial to evaluating regimens for multidrug- or rifampicin-resistant (MDR/RR) tuberculosis (TB). However, such analyses are complicated when some patients die or become lost during post-treatment follow-up. METHODS: We analyzed data on 1991 patients who successfully completed a longer MDR/RR-TB regimen containing bedaquiline and/or delamanid between 2015 and 2018 in 16 countries. Using 5 approaches for handling post-treatment deaths, we estimated 6-month post-treatment TB recurrence risk overall and by HIV status. We used inverse-probability weighting to account for patients with missing follow-up and investigated the impact of potential bias from excluding these patients without applying inverse-probability weights. RESULTS: The estimated TB recurrence risk was 7.4/1000 (95% credible interval: 3.3-12.8) when deaths were handled as non-recurrences and 7.6/1000 (3.3-13.0) when deaths were censored and inverse-probability weights were applied to account for the excluded deaths. The estimated risks of composite recurrence outcomes were 25.5 (15.3-38.1), 11.7 (6.4-18.2), and 8.6 (4.1-14.4) per 1000 for recurrence or (1) any death, (2) death with unknown or TB-related cause, or (3) TB-related death, respectively. Corresponding relative risks for HIV status varied in direction and magnitude. Exclusion of patients with missing follow-up without inverse-probability weighting had a small impact on estimates. CONCLUSIONS: The estimated 6-month TB recurrence risk was low, and the association with HIV status was inconclusive due to few recurrence events. Estimation of post-treatment recurrence will be enhanced by explicit assumptions about deaths and appropriate adjustment for missing follow-up data.

Bedaquiline Resistance after Effective Treatment of Multidrug-Resistant Tuberculosis, Namibia.

Bedaquiline is currently a key drug for treating multidrug-resistant or rifampin-resistant tuberculosis. We report and discuss the unusual development of resistance to bedaquiline in a teenager in Namibia, despite an optimal background regimen and adherence. The report highlights the risk for bedaquiline resistance development and the need for rapid drug-resistance testing.

Omadacycline pharmacokinetics/pharmacodynamics and efficacy against multidrug-resistant Mycobacterium tuberculosis in the hollow fiber system model.

Seventy-five years ago, first-generation tetracyclines demonstrated limited efficacy in the treatment of tuberculosis but were more toxic than efficacious. We performed a series of pharmacokinetic/pharmacodynamic (PK/PD) experiments with a potentially safer third-generation tetracycline, omadacycline, for the treatment of multidrug-resistant tuberculosis (MDR-TB). Mycobacterium tuberculosis (Mtb) H37Rv and an MDR-TB clinical strain (16D) were used in the minimum inhibitory concentration (MIC) and static concentration-response studies in test tubes, followed by a PK/PD study using the hollow fiber system model of TB (HFS-TB) that examined six human-like omadacycline doses. The inhibitory sigmoid maximal effect (Emax) model and Monte Carlo experiments (MCEs) were used for data analysis and clinical dose-finding, respectively. The omadacycline MIC for both Mtb H37Rv and MDR-TB clinical strain was 16 mg/L but dropped to 4 mg/L with daily drug supplementation to account for omadacycline degradation. The Mycobacteria Growth Indicator Tube MIC was 2 mg/L. In the test tubes, omadacycline killed 4.39 log10 CFU/mL in 7 days. On Day 28 of the HFS-TB study, the Emax was 4.64 log10 CFU/mL, while exposure mediating 50% of Emax (EC50) was an area under the concentration-time curve to MIC (AUC0-24/MIC) ratio of 22.86. This translates to PK/PD optimal exposure or EC80 as AUC0-24/MIC of 26.93. The target attainment probability of the 300-mg daily oral dose was 90% but fell at MIC ≧4 mg/L. Omadacycline demonstrated efficacy and potency against both drug-susceptible and MDR-TB. Further studies are needed to identify the omadacycline effect in combination therapy for the treatment of both drug-susceptible and MDR-TB.

Global burden of MDR-TB and XDR-TB attributable to high fasting plasma glucose from 1990 to 2019: a retrospective analysis based on the global burden of disease study 2019.

PURPOSE: High fasting plasma glucose (HFPG) has been identified as a risk factor for drug-resistant tuberculosis incidence and mortality. However, the epidemic characteristics of HFPG-attributable multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) remain unclear. We aimed to analyze the global spatial patterns and temporal trends of HFPG-attributable MDR-TB and XDR-TB from 1990 to 2019. METHODS: Utilizing data from the Global Burden of Disease 2019 project, annual deaths and disability-adjusted life years (DALYs) of HFPG-attributable MDR-TB and XDR-TB were conducted from 1990 to 2019. Joinpoint regression was employed to quantify trends over time. RESULTS: From 1990 to 2019, the deaths and DALYs due to HFPG-attributable MDR-TB and XDR-TB globally showed an overall increasing trend, with a significant increase until 2003 to 2004, followed by a gradual decline or stability thereafter. The low sociodemographic index (SDI) region experienced the most significant increase over the past 30 years. Regionally, Sub-Saharan Africa, Central Asia and Oceania remained the highest burden. Furthermore, there was a sex and age disparity in the burden of HFPG-attributable MDR-TB and XDR-TB, with young males in the 25-34 age group experiencing higher mortality, DALYs burden and a faster increasing trend than females. Interestingly, an increasing trend followed by a stable or decreasing pattern was observed in the ASMR and ASDR of HFPG-attributable MDR-TB and XDR-TB with SDI increasing. CONCLUSION: The burden of HFPG-attributable MDR-TB and XDR-TB rose worldwide from 1990 to 2019. These findings emphasize the importance of routine bi-directional screening and integrated management for drug-resistant TB and diabetes.

Understanding the role of video direct observed therapy for patients on an oral short-course regimen for multi-drug resistant tuberculosis: findings from a qualitative study in Eswatini.

BACKGROUND: Improving treatment success rates among multi drug-resistant tuberculosis (MDR-TB) patients is critical to reducing its incidence and mortality, but adherence poses an important challenge. Video-based direct observed therapy (vDOT) may provide adherence benefits, while addressing the time and cost burden associated with community treatment supporter (CTS)-DOT. This study explored experiences of patients, family members and healthcare workers with different DOT modalities for adherence support in Eswatini. METHODS: Between April 2021 and May 2022, thirteen men and five women with MDR-TB, ten healthcare workers, and nine caregivers were purposively sampled to include a range of characteristics and experiences with DOT modalities. Data were generated through individual in-depth interviews and a smartphone messaging application (WhatsApp). Data coding was undertaken iteratively, and thematic analysis undertaken, supported by Nvivo. RESULTS: Four themes emerged that reflected participants' experiences with different DOT modalities, including stigma, efficiency, perceived risks of TB acquisition, and patient autonomy. vDOT was appreciated by patients for providing them with privacy and shielding them from stigmatisation associated with being seen in TB clinics or with community treatment supporters. vDOT was also seen as more efficient than CTS-DOT. Health workers acknowledged that it saved time, allowing them to attend to more patients, while many patients found vDOT more convenient and less expensive by removing the need to travel for in-person consultations. Health workers also appreciated vDOT because it reduced risks of TB acquisition by minimising exposure through virtual patient monitoring. Although many patients appreciated greater autonomy in managing their illness through vDOT, others preferred human contact or struggled with making video recordings. Most family members appreciated vDOT, although some resented feeling removed from the process of supporting loved ones. CONCLUSIONS: vDOT was generally appreciated by MDR-TB patients, their family members and health workers as it addressed barriers to adherence which could contribute to improved treatment completion rates and reduced workplace exposure. However, patients should be offered an alternative to vDOT such as CTS-DOT if this modality does not suit their circumstances or preferences.

Treatment outcomes of standardized injectable shorter regimen for multi-drugs resistant tuberculosis in Ethiopia: a retrospective cohort study.

BACKGROUND: The injectable shorter multi-drug resistant tuberculosis (MDR-TB) regimen, has been reported to be less costly and more effective in the treatment of MDR-TB compared to the longer regimen. Ethiopia introduced the injectable shorter regimen (SR) in April 2018 following official recommendation by the World Health Organization (WHO) in 2016. While the WHO recommendation was based on evidence coming from extensive programmatic studies in some Asian and African countries, there is paucity of information on patient outcomes in the Ethiopian context. Thus, we aimed to assess the treatment outcomes and identify factors associated with the outcomes of MDR-TB patients on injectable SR. METHODS: A multi-center facility-based retrospective cohort study was conducted in Ethiopia on 245 MDR-TB patients who were treated between April 2018 and March 2020. Data were collected from patients' medical records and analyzed using SPSS version 25. Descriptive statistics was used to summarize the results while inferential analysis was employed to investigate predictors of treatment outcomes and survival status. RESULTS: A total of 245 patients were included in the study, with 129 (52.7%) of them being female. Median age of the patients was 27 (IQR: 21-33). The overall treatment success rate was 87.8%, with 156 (63.7%) cured and 59 (24.1%) patients who completed treatment. The unfavorable outcomes accounted for 12.2%, with 16 (6.5%) treatment failure, 8 (3.3%) death and 6 (2.4%) lost to follow up. Majority of the unfavorable outcomes occurred during the early phase of therapy, with median time to event of 1.8 months (95% CI: 0.99-2.69). The use of khat (a green leafy shrub abused for its stimulant like effect) and being diagnosed with MDR-TB than rifampicin resistant only, were identified as independent factors associated with unfavorable outcomes. CONCLUSION: The injectable SR for MDR-TB was found to have positive treatment outcomes in the context of programmatic management in Ethiopia.

N-Acyl phenothiazines as mycobacterial ATP synthase inhibitors: Rational design, synthesis and in vitro evaluation against drug sensitive, RR and MDR-TB.

The mycobacterial F-ATP synthase is responsible for the optimal growth, metabolism and viability of Mycobacteria, establishing it as a validated target for the development of anti-TB therapeutics. Herein, we report the discovery of an N-acyl phenothiazine derivative, termed PT6, targeting the mycobacterial F-ATP synthase. PT6 is bactericidal and active against the drug sensitive, Rifampicin-resistant as well as Multidrug-resistant tuberculosis strains. Compound PT6 showed noteworthy inhibition of F-ATP synthesis, exhibiting an IC50 of 0.788 µM in M. smegmatis IMVs and was observed that it could deplete intracellular ATP levels, exhibiting an IC50 of 30 µM. PT6 displayed a high selectivity towards mycobacterial ATP synthase compared to mitochondrial ATP synthase. Compound PT6 showed a minor synergistic effect in combination with Rifampicin and Isoniazid. PT6 demonstrated null cytotoxicity as confirmed by assessing its toxicity against VERO cell lines. Further, the binding mechanism and the activity profile of PT6 were validated by employing in silico techniques such as molecular docking, Prime MM/GBSA, DFT and ADMET analysis. These results suggest that PT6 presents an attractive lead for the discovery of a novel class of mycobacterial F-ATP synthase inhibitors.

Detection of multidrug-resistance in Mycobacterium tuberculosis by phenotype- and molecular-based assays.

BACKGROUND: The whole-genome sequencing (WGS) is becoming an increasingly effective tool for rapid and accurate detection of drug resistance in Mycobacterium tuberculosis complex (MTBC). This approach, however, has still been poorly evaluated on strains from Central and Eastern European countries. The purpose of this study was to assess the performance of WGS against conventional drug susceptibility testing (DST) for the detection of multi-drug resistant (MDR) phenotypes among MTBC clinical strains from Poland and Lithuania. METHODS: The study included 208 MTBC strains (130 MDR; 78 drug susceptible), recovered from as many tuberculosis patients in Lithuania and Poland between 2018 and 2021. Resistance to rifampicin (RIF) and isoniazid (INH) was assessed by Critical Concentration (CC) and Minimum Inhibitory Concentration (MIC) DST as well as molecular-based techniques, including line-probe assay (LPA) and WGS. The analysis of WGS results was performed using bioinformatic pipeline- and software-based tools. RESULTS: The results obtained with the CC DST were more congruent with those by LPA compared to pipeline-based WGS. Software-based tools showed excellent concordance with pipeline-based analysis in prediction of RIF/INH resistance. The RIF-resistant strains demonstrated a relatively homogenous MIC distribution with the mode at the highest tested MIC value. The most frequent RIF-resistance conferring mutation was rpoB S450L. The mode MIC for INH was two-fold higher among double katG and inhA mutants than among single katG mutants. The overall rate of discordant results between all methods was calculated at 5.3%. Three strains had discordant results by both genotypic methods (LPA and pipeline-based WGS), one strain by LPA only, three strains by MIC DST, two strains by both MIC DST and pipeline-based WGS, and the remaining two strains showed discordant results with all three methods, compared to CC DST. CONCLUSIONS: Considering MIC DST results, current CCs of the first-line anti-TB drugs might be inappropriately high and may need to be revised. Both molecular methods demonstrated 100% specificity, while pipeline-based WGS had slightly lower sensitivity for RIF and INH than LPA, compared to CC DST.

Exploring health care providers' engagement in prevention and management of multidrug resistant Tuberculosis and its factors in Hadiya Zone health care facilities: qualitative study.

BACKGROUND: Engagement of healthcare providers is one of the World Health Organization strategies devised for prevention and provision of patient centered care for multidrug resistant tuberculosis. The need for current research question rose because of the gaps in evidence on health professional's engagement and its factors in multidrug resistant tuberculosis service delivery as per the protocol in the prevention and management of multidrug resistant tuberculosis. PURPOSE: The purpose of this study was to explore the level of health care providers' engagement in multidrug resistant tuberculosis prevention and management and influencing factors in Hadiya Zone health facilities, Southern Ethiopia. METHODS: Descriptive phenomenological qualitative study design was employed between 02 May and 09 May, 2019. We conducted a key informant interview and focus group discussions using purposely selected healthcare experts working as directly observed treatment short course providers in multidrug resistant tuberculosis treatment initiation centers, program managers, and focal persons. Verbatim transcripts were translated to English and exported to open code 4.02 for line-by-line coding and categorization of meanings into same emergent themes. Thematic analysis was conducted based on predefined themes for multidrug resistant tuberculosis prevention and management and core findings under each theme were supported by domain summaries in our final interpretation of the results. To maintain the rigors, Lincoln and Guba's parallel quality criteria of trustworthiness was used particularly, credibility, dependability, transferability, confirmability and reflexivity. RESULTS: Total of 26 service providers, program managers, and focal persons were participated through four focus group discussion and five key informant interviews. The study explored factors for engagement of health care providers in the prevention and management of multidrug resistant tuberculosis in five emergent themes such as patients' causes, perceived susceptibility, seeking support, professional incompetence and poor linkage of the health care facilities. Our findings also suggest that service providers require additional training, particularly in programmatic management of drug-resistant tuberculosis. CONCLUSION: The study explored five emergent themes: patient's underlying causes, seeking support, perceived susceptibility, professionals' incompetence and health facilities poor linkage. Community awareness creation to avoid fear of discrimination through provision of support for those with multidrug resistant tuberculosis is expected from health care providers using social behavioral change communication strategies. Furthermore, program managers need to follow the recommendations of World Health Organization for engaging healthcare professionals in the prevention and management of multidrug resistant tuberculosis and cascade trainings in clinical programmatic management of the disease for healthcare professionals.

Collaboration for implementation of decentralisation policy of multi drug-resistant tuberculosis services in Zambia.

BACKGROUND: Multi-drug-resistant tuberculosis (MDR-TB) infections are a public health concern. Since 2017, the Ministry of Health (MoH) in Zambia, in collaboration with its partners, has been implementing decentralised MDR-TB services to address the limited community access to treatment. This study sought to explore the role of collaboration in the implementation of decentralised multi drug-resistant tuberculosis services in Zambia. METHODS: A qualitative case study design was conducted in selected provinces in Zambia using in-depth and key informant interviews as data collection methods. We conducted a total of 112 interviews involving 18 healthcare workers, 17 community health workers, 32 patients and 21 caregivers in healthcare facilities located in 10 selected districts. Additionally, 24 key informant interviews were conducted with healthcare workers managers at facility, district, provincial, and national-levels. Thematic analysis was employed guided by the Integrative Framework for Collaborative Governance. FINDINGS: The principled engagement was shaped by the global health agenda/summit meeting influence on the decentralisation of TB, engagement of stakeholders to initiate decentralisation, a supportive policy environment for the decentralisation process and guidelines and quarterly clinical expert committee meetings. The factors that influenced the shared motivation for the introduction of MDR-TB decentralisation included actors having a common understanding, limited access to health facilities and emergency transport services, a shared understanding of challenges in providing optimal patient monitoring and review and their appreciation of the value of evidence-based decision-making in the implementation of MDR- TB decentralisation. The capacity for joint action strategies included MoH initiating strategic partnerships in enhancing MDR-TB decentralisation, the role of leadership in organising training of healthcare workers and of multidisciplinary teams, inadequate coordination, supervision and monitoring of laboratory services and joint action in health infrastructural rehabilitation. CONCLUSIONS: Principled engagement facilitated the involvement of various stakeholders, the dissemination of relevant policies and guidelines and regular quarterly meetings of clinical expert committees to ensure ongoing support and guidance. A shared motivation among actors was underpinned by a common understanding of the barriers faced while implementing decentralisation efforts. The capacity for joint action was demonstrated through several key strategies, however, challenges such as inadequate coordination, supervision and monitoring of laboratory services, as well as the need for collaborative efforts in health infrastructural rehabilitation were observed. Overall, collaboration has facilitated the creation of a more responsive and comprehensive TB care system, addressing the critical needs of patients and improving health outcomes.

Characteristic SNPs defining the major multidrug-resistant Mycobacterium tuberculosis clusters identified by EuSeqMyTB to support routine surveillance, EU/EEA, 2017 to 2019.

BackgroundThe EUSeqMyTB project, conducted in 2020, used whole genome sequencing (WGS) for surveillance of drug-resistant Mycobacterium tuberculosis in the European Union/European Economic Area (EU/EEA) and identified 56 internationally clustered multidrug-resistant (MDR) tuberculosis (TB) clones.AimWe aimed to define and establish a rapid and computationally simple screening method to identify probable members of the main cross-border MDR-TB clusters in WGS data to facilitate their identification and track their future spread.MethodsWe screened 34 of the larger cross-border clusters identified in the EuSeqMyTB pilot study (2017-19) for characteristic single nucleotide polymorphism (SNP) signatures that could identify and define members of each cluster. We also linked this analysis with published clusters identified in previous studies and identified more distant genetic relationships between some of the current clusters.ResultsA panel of 30 characteristic SNPs is presented that can be used as an initial (routine) screen for members of each cluster. For four of the clusters, no unique defining SNP could be identified; three of these are closely related (within approximately 20 SNPs) to one or more other clusters and likely represent a single established MDR-TB clade composed of multiple recent subclusters derived from the previously described ECDC0002 cluster.ConclusionThe identified SNP signatures can be integrated into routine pipelines and contribute to the more effective monitoring, rapid and widespread screening for TB. This SNP panel will also support accurate communication between laboratories about previously identified internationally transmitted MDR-TB genotypes.

First detection of a Mycobacterium tuberculosis XDR clinical isolate harbouring an RpoB I491F mutation in a Ukrainian patient treated in Germany, October 2023.

This report documents the case of a Ukrainian patient infected with an extensively drug-resistant (XDR) lineage 2 Mycobacterium tuberculosis strain harbouring the rifampicin resistance mutation RpoB I491F. This mutation is not detected by routine molecular WHO-recommended rapid diagnostics, complicating the detection and treatment of these strains. The occurrence of such mutations underscores the need for enhanced diagnostic techniques and tailored treatment regimens, especially in eastern Europe where lineage 2 strains and XDR-tuberculosis are prevalent.

Distribution of tuberculosis in migrant children and young people in Europe: a retrospective database analysis of European data.

OBJECTIVE: The burden of tuberculosis (TB) in migrant children and young people (CYP) is commonly overlooked, despite the increasing incidence of TB in migrant populations in the European region. This study aimed to examine the distribution and disease characteristics of TB among migrant and native-born CYP through analysis of data from the European Centre for Disease Prevention and Control (ECDC) surveillance system (TESSy). STUDY DESIGN: Retrospective database analysis. METHODS: A retrospective database analysis was conducted on all CYP TB cases (0-17 years) reported to TESSy (1995-2017), exploring distribution, site of TB, and presence of MDR-TB using multivariate analysis in R statistical software. RESULTS: Of the 73,176 CYP TB cases reported in the EU/EFTA (1995-2017), 24.4% (n = 17,879) occurred in migrant CYP and 75.6% (n = 55,297) occurred in native-born CYP. Migrant CYP were more likely (P < 0.001) to have pulmonary TB (OR: 1.90; 95% CI: 1.74-2.09) and unsuccessful treatment outcomes (OR: 2.05; 95% CI: 1.74-2.40) compared to native-born CYP. The proportion of extrapulmonary TB, compared to pulmonary TB across total CYP cases was higher than the existing evidence base. CONCLUSIONS: Overall, there were significant differences in the site of TB and treatment outcomes between migrant and native-born CYP. To improve outcomes, TB screening and detection practices should focus on facilitating care in migrant CYP. However, to better understand the implications of these findings on broader TB control, TB among CYP should be addressed more frequently in reports and research.

Pangenomic analyses of tuberculosis strains to identify resistomes using computational approaches.

Objective: To locate resistomes in tuberculosis strains, to determine the severity of drug resistance, and to infer its implications with respect to high tuberculosis prevalence in a Third World setting. METHODS: The pangenomic study was conducted from October 2022 to January 2023 in Sir Syed University of Engineering and Technology, Karachi, and comprised 2012-22 data on multiple sequence alignment to assess the genetic evolution of tuberculosis strains. Antibiotic resistance drug classes were identified using the Canadian Antibiotic Resistance Database, which entailed multidrug-resistant and extremely drug-resistant strains. Also, GenBank was used for tuberculosis genome FASTA (fast-all; nucleotide and protein sequence representation) files, prediction of resistome sequences on the basis of Canadian Antibiotic Resistance Database, and multiple sequence alignment was done in Mauve. RESULTS: Evolutionarily, the 6 strains identified were structurally similar with polymorphisms in their core chromosomal regions. Their resistome genes showed perfect hits for isoniazid, rifamycin, cephalosporin, fluoroquinolone, aminoglycosides, penem, penam and cephamycin. Conclusion: Drugs discovered in antibiotic resistance genes are now less effective in treatment, and have the potential to develop into more dangerous bacteria, if not monitored. For treatment, staying long durations in hospitals for quality healthcare and supervision in third world countries is unaffordable.

Tuberculosis in Poland in 2021. / Gruzlica w Polsce w 2021 r.

AIM OF THE STUDY: 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. MATERIAL AND METHODS: 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." RESULTS: 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). CONCLUSIONS: 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).

Molecular epidemiology and transmission dynamics of multi-drug resistant tuberculosis strains using whole genome sequencing in the Amhara region, Ethiopia.

BACKGROUND: Drug resistant Mycobacterium tuberculosis prevention and care is a major challenge in Ethiopia. The World health organization has designated Ethiopia as one of the 30 high burden multi-drug resistant tuberculosis (MDR-TB) countries. There is limited information regarding genetic diversity and transmission dynamics of MDR-TB in Ethiopia. OBJECTIVE: To investigate the molecular epidemiology and transmission dynamics of MDR-TB strains using whole genome sequence (WGS) in the Amhara region. METHODS: Forty-five MDR-TB clinical isolates from Amhara region were collected between 2016 and 2018, and characterized using WGS and 24-loci Mycobacterium Interspersed Repetitive Units Variable Number of Tandem Repeats (MIRU-VNTR) typing. Clusters were defined based on the maximum distance of 12 single nucleotide polymorphisms (SNPs) or alleles as the upper threshold of genomic relatedness. Five or less SNPs or alleles distance or identical 24-loci VNTR typing is denoted as surrogate marker for recent transmission. RESULTS: Forty-one of the 45 isolates were analyzed by WGS and 44% (18/41) of the isolates were distributed into 4 clusters. Of the 41 MDR-TB isolates, 58.5% were classified as lineage 4, 36.5% lineage 3 and 5% lineage 1. Overall, TUR genotype (54%) was the predominant in MDR-TB strains. 41% (17/41) of the isolates were clustered into four WGS groups and the remaining isolates were unique strains. The predominant cluster (Cluster 1) was composed of nine isolates belonging to lineage 4 and of these, four isolates were in the recent transmission links. CONCLUSIONS: Majority of MDR-TB strain cluster and predominance of TUR lineage in the Amhara region give rise to concerns for possible ongoing transmission. Efforts to strengthen TB laboratory to advance diagnosis, intensified active case finding, and expanded contact tracing activities are needed in order to improve rapid diagnosis and initiate early treatment. This would lead to the interruption of the transmission chain and stop the spread of MDR-TB in the Amhara region.

Optimizing Moxifloxacin Dose in MDR-TB Participants with or without Efavirenz Coadministration Using Population Pharmacokinetic Modeling.

Moxifloxacin is included in some treatment regimens for drug-sensitive tuberculosis (TB) and multidrug-resistant TB (MDR-TB). Aiming to optimize dosing, we described moxifloxacin pharmacokinetic and MIC distribution in participants with MDR-TB. Participants enrolled at two TB hospitals in South Africa underwent intensive pharmacokinetic sampling approximately 1 to 6 weeks after treatment initiation. Plasma drug concentrations and clinical data were analyzed using nonlinear mixed-effects modeling with simulations to evaluate doses for different scenarios. We enrolled 131 participants (54 females), with median age of 35.7 (interquartile range, 28.5 to 43.5) years, median weight of 47 (42.0 to 54.0) kg, and median fat-free mass of 40.1 (32.3 to 44.7) kg; 79 were HIV positive, 29 of whom were on efavirenz-based antiretroviral therapy. Moxifloxacin pharmacokinetics were described with a 2-compartment model, transit absorption, and elimination via a liver compartment. We included allometry based on fat-free mass to estimate disposition parameters. We estimated an oral clearance for a typical patient to be 17.6 L/h. Participants treated with efavirenz had increased clearance, resulting in a 44% reduction in moxifloxacin exposure. Simulations predicted that, even at a median MIC of 0.25 (0.06 to 16) mg/L, the standard daily dose of 400 mg has a low probability of attaining the ratio of the area under the unbound concentration-time curve from 0 to 24 h to the MIC (fAUC0-24)/MIC target of >53, particularly in heavier participants. The high-dose WHO regimen (600 to 800 mg) yielded higher, more balanced exposures across the weight ranges, with better target attainment. When coadministered with efavirenz, moxifloxacin doses of up to 1,000 mg are needed to match these exposures. The safety of higher moxifloxacin doses in clinical settings should be confirmed.

Pharmacokinetics and Efficacy of the Benzothiazinone BTZ-043 against Tuberculous Mycobacteria inside Granulomas in the Guinea Pig Model.

Tuberculosis (TB), caused by Mycobacterium tuberculosis, is the world's leading cause of mortality from a single bacterial pathogen. With increasing frequency, emergence of drug-resistant mycobacteria leads to failures of standard TB treatment regimens. Therefore, new anti-TB drugs are urgently required. BTZ-043 belongs to a novel class of nitrobenzothiazinones, which inhibit mycobacterial cell wall formation by covalent binding of an essential cysteine in the catalytic pocket of decaprenylphosphoryl-ß-d-ribose oxidase (DprE1). Thus, the compound blocks the formation of decaprenylphosphoryl-ß-d-arabinose, a precursor for the synthesis of arabinans. An excellent in vitro efficacy against M. tuberculosis has been demonstrated. Guinea pigs are an important small-animal model to study anti-TB drugs, as they are naturally susceptible to M. tuberculosis and develop human-like granulomas after infection. In the current study, dose-finding experiments were conducted to establish the appropriate oral dose of BTZ-043 for the guinea pig. Subsequently, it could be shown that the active compound was present at high concentrations in Mycobacterium bovis BCG-induced granulomas. To evaluate its therapeutic effect, guinea pigs were subcutaneously infected with virulent M. tuberculosis and treated with BTZ-043 for 4 weeks. BTZ-043-treated guinea pigs had reduced and less necrotic granulomas than vehicle-treated controls. In comparison to the vehicle controls a highly significant reduction of the bacterial burden was observed after BTZ-043 treatment at the site of infection and in the draining lymph node and spleen. Together, these findings indicate that BTZ-043 holds great promise as a new antimycobacterial drug.

Resistance patterns among drug-resistant tuberculosis patients and trends-over-time analysis of national surveillance data in Gabon, Central Africa.

OBJECTIVE: Routinely generated surveillance data are important for monitoring the effectiveness of MDR-TB control strategies. Incidence of rifampicin-resistant tuberculosis (RR-TB) is a key indicator for monitoring MDR-TB. METHODS: In a longitudinal nationwide retrospective study, 8 years (2014-2021) of sputum samples from presumptively drug-resistant tuberculosis patients from all regions of Gabon were referred to the national tuberculosis reference laboratory. Samples were analysed using GeneXpert MTB/RIF and Genotype MTBDRsl version 2/Line Probe Assay. RESULTS: Of 3057 sputum samples from presumptive tuberculosis patients, both from local hospital and from referral patients, 334 were RR-TB. The median patient age was 33 years (interquartile range 26-43); one third was newly diagnosed drug-resistant tuberculosis patients; one-third was HIV-positive. The proportion of men with RR-TB was significantly higher than that of women (55% vs 45%; p < 0.0001). Patients aged 25-35 years were most affected (32%; 108/334). The cumulative incidence of RR-TB was 17 (95% CI 15-19)/100,000 population over 8 years. The highest incidences were observed in 2020 and 2021. A total of 281 samples were analysed for second-line drug resistance. The proportions of study participants with MDR-TB, pre-XDR-TB and XDR-TB were 90.7% (255/281), 9% (25/281) and 0.3% (1/281), respectively. The most-common mutations in fluoroquinolones resistance isolates was gyrA double mutation gyrA MUT3B and MUT3C (23%; 4/17). Most (64%; 6/8) second-line injectable drugs resistance isolates were characterised by missing both rrs WT2 and MUT2 banding. CONCLUSION: The increasing incidence of MDR-TB infection in Gabon is alarming. It is highest in the 25-35 years age category. The incidence of MDR-TB infection in treatment-naïve patients calls for case finding and contact tracing strategy improvement.