Management of patients with multidrug-resistant/extensively drug-resistant tuberculosis in Europe: a TBNET consensus statement

Triple combination dry powder formulation of pretomanid, moxifloxacin, and pyrazinamide for treatment of multidrug-resistant tuberculosis

Both latent and multidrug-resistant tuberculosis (TB) have been causing significant concern worldwide. A novel drug, pretomanid (PA-824), has shown a potent bactericidal effect against both active and latent forms of Mycobacterium tuberculosis (MTb) and a synergistic effect when combined with pyrazinamide and moxifloxacin. This study aimed to develop triple combination spray dried inhalable formulations composed of antitubercular drugs, pretomanid, moxifloxacin, and pyrazinamide (1:2:8 w/w/w), alone (PaMP) and in combination with an aerosolization enhancer, L-leucine (20 % w/w, PaMPL). The formulation PaMPL consisted of hollow, spherical, dimpled particles (<5 μm) and showed good aerosolization behaviour with a fine particle fraction of 70 %. Solid-state characterization of formulations with and without L-leucine confirmed the amorphous nature of moxifloxacin and pretomanid and the crystalline nature of pyrazinamide with polymorphic transformation after the spray drying process. Further, the X-ray photoelectron spectroscopic analysis revealed the predominant surface composition of L-leucine on PaMPL dry powder particles. The dose-response cytotoxicity results showed pyrazinamide and moxifloxacin were non-toxic in both A549 and Calu-3 cell lines up to 150 µg/mL. However, the cell viability gradually decreased to 50 % when the pretomanid concentration increased to 150 µg/mL. The in vitro efficacy studies demonstrated that the triple combination formulation had more prominent antibacterial activity with a minimum inhibitory concentration (MIC) of 1 µg/mL against the MTb H37Rv strain as compared to individual drugs. In conclusion, the triple combination of pretomanid, moxifloxacin, and pyrazinamide as an inhalable dry powder formulation will potentially improve treatment efficacy with fewer systemic side effects in patients suffering from latent and multidrug-resistant TB.

Contact investigation in multidrug-resistant tuberculosis: ethical challenges

Contact investigation is an evidence-based intervention of multidrug-resistant tuberculosis (MDR-TB) to protect public health by interrupting the chain of transmission. In pursuit of contact investigation, patients' MDR-TB status has to be disclosed to third parties (to the minimum necessary) for tracing the contacts. Nevertheless, disclosure to third parties often unintentionally leads the MDR-TB patients suffered from social discrimination and stigma. For this reason, patients are less inclined to reveal their MDR-TB status and becomes a significant issue in contact investigation. This issue certainly turns into a negative impact on the public interest. Tension between keeping MDR-TB status confidential and safeguarding public health arises in relation to this issue. Regarding MDR-TB management, patient compliance with treatment and contact investigation are equally important. Patients might fail to comply with anti-TB therapy and be reluctant to seek healthcare due to disclosure concerns. In order to have treatment adherence, MDRTB patients should not live through social discrimination and stigma arising from disclosure and TB team has a duty to support them as a mean of reciprocity. However, implementation of contact investigation as a public health policy can still be challenging even with promising reciprocal support to the patients because MDR-TB patients are living in different contexts and situations. There can be no straight forward settlement but an appropriate justification for each distinct context is needed to strike a balance between individual confidentiality and public interest.

Push forward LC-MS-based therapeutic drug monitoring and pharmacometabolomics for anti-tuberculosis precision dosing and comprehensive clinical management

The spread of tuberculosis (TB), especially multidrug-resistant TB and extensively drug-resistant TB, has strongly motivated the research and development of new anti-TB drugs. New strategies to facilitate drug combinations, including pharmacokinetics-guided dose optimization and toxicology studies of first- and second-line anti-TB drugs have also been introduced and recommended. Liquid chromatography-mass spectrometry (LC-MS) has arguably become the gold standard in the analysis of both endo- and exo-genous compounds. This technique has been applied successfully not only for therapeutic drug monitoring (TDM) but also for pharmacometabolomics analysis. TDM improves the effectiveness of treatment, reduces adverse drug reactions, and the likelihood of drug resistance development in TB patients by determining dosage regimens that produce concentrations within the therapeutic target window. Based on TDM, the dose would be optimized individually to achieve favorable outcomes. Pharmacometabolomics is essential in generating and validating hypotheses regarding the metabolism of anti-TB drugs, aiding in the discovery of potential biomarkers for TB diagnostics, treatment monitoring, and outcome evaluation. This article highlighted the current progresses in TDM of anti-TB drugs based on LC-MS bioassay in the last two decades. Besides, we discussed the advantages and disadvantages of this technique in practical use. The pressing need for non-invasive sampling approaches and stability studies of anti-TB drugs was highlighted. Lastly, we provided perspectives on the prospects of combining LC-MS-based TDM and pharmacometabolomics with other advanced strategies (pharmacometrics, drug and vaccine developments, machine learning/artificial intelligence, among others) to encapsulate in an all-inclusive approach to improve treatment outcomes of TB patients.

Development of a Conceptual Framework for Tuberculosis Management and Control; an Evidence Synthesis Using Text Mining Software: A Review

Background

The use of electronic systems supported by text-mining software applications that support the End TB strategy' needs to be explored. This study aimed to address this knowledge gap, and synthesis of evidence.

Methods

The PubMed database was searched for structured review articles published in English since 2012 on interventions to control and manage TB. Nine hundred twenty-five articles met the inclusion criteria. The included articles were synthesized using the text and content analysis software Leximancer. The themes were chosen based on the hit words that emerged in the frequency and heat maps. After the themes were chosen, the concept built the themes based on likelihood.

Results

The framework resulting in the study focuses on early detection and treatment to minimize the chance of TB transmission in the population, especially for highly susceptable populations. The main area highlighted is the appropriate screening and treatment domains. The framework generated in this study is somewhat in line with the WHO Final TB Strategy. This study highlights the importance of improving TB prevention through a patient-centered approach and protecting susceptible populations.

Conclusion

Our findings will be helpful in guiding TB practice, policy development and future research. Future research can elaborate the framework and elicit feedback from TB management stakeholdesr to assess its utility.

Pediatric multi-drug-resistant tuberculosis in Germany - diagnostic and therapeutic challenges of an "orphan disease"

Delay in diagnosing multidrug-resistant tuberculosis (MDR-pTB) in children prolongs time to effective treatment. Data on risk factors for pediatric MDR from low-incidence countries are scarce. Retrospective nationwide case-control study to analyze MDR-pTB cases in Germany between 2010 and 2020 in comparison to a drug-susceptible (DS)-pTB group. We included 52 MDR cases (24 tuberculosis (TB), 28 TB infection (TBI); mean age 7.3 years) and 56 DS cases (31 TB, 26 TBI; mean age 7.9 years). Groups were similar for sex, household size, and migration background. Compared to the DS group, more children with MDR were born in the Commonwealth of Independent States (CIS) (22% MDR-pTB vs. 13% DS-pTB, n.s.) and had more MDR index cases (94% MDR-pTB, 5% DS-pTB, p < 0.001). The interval between first healthcare contact and initiation of effective therapy was significantly longer in MDR-pTB (47 days) than in DS-pTB (11 days, p < 0.001), correlating with disease progression. Treatment for MDR-pTB was successful in 74%, but 22% experienced long-term adverse effects (e.g., hepatopathy, hearing loss).

CONCLUSIONS

Close contact to MDR cases or birth in MDR-TB-high-incidence countries are risk factors for MDR-pTB. Early identification of potential MDR index cases by contact investigation, and susceptibility testing in children from high-burden MDR-TB countries are essential for timely diagnosis and treatment, reducing the severity of disease and treatment side effects.

TRIAL REGISTRATION

Deutsches Register Klinischer Studien ( https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00023817 ), DRKS00023817, 2020-09-08.

WHAT IS KNOWN

•Management of children with MDR-TB remains challenging due to difficulties in diagnosing MDR-TB (lack of information on MDR index case, lack of microbiological confirmation in paucibacillary disease). •Choice of treatment regimen and monitoring of side effects.

WHAT IS NEW

•Children with an MDR-TB index or born in a MDR-TB-high-incidence country are at higher risk of developing MDR-TB in a low incidence country. •The time lag to initiate treatment in MDR-TB is longer than in DS-TB and MDR-TB treatment involves a higher risk of adverse effects in longer treatment regimens especially with injectables.

Investigation of efflux pump genes in isoniazid resistant Mycobacterium tuberculosis isolates

BACKGROUND

Tuberculosis (TB) is one of the most important infectious diseases worldwide. Resistance to antituberculosis drugs develops because of genetic mutations that render drug-activating enzymes inactive, changes in cell wall permeability, and increased expression of efflux pump genes and also combination therapy with efflux pump inhibitors may be more effective in drug-resistant TB patients.

AIMS

To investigate the effect of verapamil (VR) on isonicotinic acid hydrazide (INH) resistance and the expression of 21 efflux pump genes in INH monoresistant MTBC clinical isolates.

STUDY DESIGN

In vitro study.

METHODS

In our mycobacteriology laboratory, 10 INH monoresistant and 10 primary anti-TB drug-susceptible MTBC clinical isolates were selected. Drug susceptibilities for INH and VR were studied by resazurin microtiter plate method and minimum inhibitory concentration (MIC) was determined. Additionally, mRNA gene expressions were investigated by quantitative Real Time Polymerase Chain Reaction for 21 efflux gene regions.

RESULTS

While no change was observed in INH MICs of susceptible isolates under VR effect, 6 (60%) of the 10 INH-resistant isolates showed a decrease of less than one dilution in INH MIC under VR effect. VR significantly reduced resistance in resistant isolates (p ​< ​0.05). INH monoresistant MTBC isolates showed a 2.85-fold expression increase in the Rv1634 region of the Major Facilitator Superfamily efflux family under INH stress (p ​= ​0.029). No statistically significant change was observed in other efflux gene regions. Herein, increased expression was observed in the Rv1634 region, consistent with other studies in the literature, and this was associated with drug resistance. No significant change in expression was detected in other gene regions.

CONCLUSION

The effect of efflux pump inhibitor VR on INH MIC levels is promising for the treatment of resistant TB. However, studies with more resistant strains are needed to evaluate the efficacy of efflux pump genes.

A Single-Run HPLC-MS Multiplex Assay for Therapeutic Drug Monitoring of Relevant First- and Second-Line Antibiotics in the Treatment of Drug-Resistant Tuberculosis

The treatment of drug-resistant Mycobacterium tuberculosis relies on complex antibiotic therapy. Inadequate antibiotic exposure can lead to treatment failure, acquired drug resistance, and an increased risk of adverse events. Therapeutic drug monitoring (TDM) can be used to optimize the antibiotic exposure. Therefore, we aimed to develop a single-run multiplex assay using high-performance liquid chromatography-mass spectrometry (HPLC-MS) for TDM of patients with multidrug-resistant, pre-extensively drug-resistant and extensively drug-resistant tuberculosis. A target profile for sufficient performance, based on the intended clinical application, was established and the assay was developed accordingly. Antibiotics were analyzed on a zwitterionic hydrophilic interaction liquid chromatography column and a triple quadrupole mass spectrometer using stable isotope-labeled internal standards. The assay was sufficiently sensitive to monitor drug concentrations over five half-lives for rifampicin, rifabutin, levofloxacin, moxifloxacin, bedaquiline, linezolid, clofazimine, terizidone/cycloserine, ethambutol, delamanid, pyrazinamide, meropenem, prothionamide, and para-amino salicylic acid (PAS). Accuracy and precision were sufficient to support clinical decision making (≤±15% in clinical samples and ±20-25% in spiked samples, with 80% of future measured concentrations predicted to fall within ±40% of nominal concentrations). The method was applied in the TDM of two patients with complex drug-resistant tuberculosis. All relevant antibiotics from their regimens could be quantified and high-dose therapy was initiated, followed by microbiological conversion. In conclusion, we developed a multiplex assay that enables TDM of the relevant first- and second-line anti-tuberculosis medicines in a single run and was able to show its applicability in TDM of two drug-resistant tuberculosis patients.

Analysis of whiB7 in Mycobacterium tuberculosis reveals novel AT-hook deletion mutations

Mutations in whiB7 have been associated with both hypersusceptibility and resistance to various antibiotics in Mycobacterium tuberculosis (Mtb). Unlocking the secrets of antibiotic resistance in the bacterium, we examined mutations in the coding sequences of whiB7 of over 40,000 diverse Mtb isolates. Our results unveil the dominant c.191delG (Gly64delG) mutation, present in all members of the lineage L1.2.2 and its impact on WhiB7's conserved GVWGG-motif, causing conformational changes and deletion of the C-terminal AT-hook. Excitingly, we discovered six unique mutations associated with partial or total deletion of the AT-hook, specific to certain sublineages. Our findings suggest the selective pressures driving these mutations, underlining the potential of genomics to advance our understanding of Mtb's antibiotic resistance. As tuberculosis remains a global health threat, our study offers valuable insights into the diverse nature and functional consequences of whiB7 mutations, paving the way for the development of novel therapeutic interventions.

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

Objective

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.

Methods

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.

Results

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.

Conclusion

Local TB infections are complex and diverse; therefore, more comprehensive monitoring methods are needed to curb the spread of MDR-TB.

Clinical implications of molecular drug resistance testing for Mycobacterium tuberculosis: a 2023 TBnet/RESIST-TB consensus statement

Drug-resistant tuberculosis is a substantial health-care concern worldwide. Despite culture-based methods being considered the gold standard for drug susceptibility testing, molecular methods provide rapid information about the Mycobacterium tuberculosis mutations associated with resistance to anti-tuberculosis drugs. This consensus document was developed on the basis of a comprehensive literature search, by the TBnet and RESIST-TB networks, about reporting standards for the clinical use of molecular drug susceptibility testing. Review and the search for evidence included hand-searching journals and searching electronic databases. The panel identified studies that linked mutations in genomic regions of M tuberculosis with treatment outcome data. Implementation of molecular testing for the prediction of drug resistance in M tuberculosis is key. Detection of mutations in clinical isolates has implications for the clinical management of patients with multidrug-resistant or rifampicin-resistant tuberculosis, especially in situations when phenotypic drug susceptibility testing is not available. A multidisciplinary team including clinicians, microbiologists, and laboratory scientists reached a consensus on key questions relevant to molecular prediction of drug susceptibility or resistance to M tuberculosis, and their implications for clinical practice. This consensus document should help clinicians in the management of patients with tuberculosis, providing guidance for the design of treatment regimens and optimising outcomes.

The socio-demographic, clinical characteristics and outcomes of tuberculosis among HIV infected adults in Lithuania: A thirteen-year analysis

BACKGROUND

Tuberculosis (TB) is a public health problem in Lithuania, among the 18 high-priority TB countries in the European region, and the most common AIDS-indicative disease with the highest proportion in the EU/EEA since 2015. The study aimed to identify socio-demographic, clinical characteristics and their relationship with TB outcomes in TB-HIV co-infected patients in Lithuania.

METHODS

A retrospective chart review analysed the characteristics of TB-HIV co-infected adults registered in State Information System of Tuberculosis over 2008-2020. The factors associated with drug-resistant TB and unsuccessful treatment outcome were identified by multivariable logistic regression.

RESULTS

The study included 345 cases in 311 patients (239 new, 106 previously treated cases), median age 40 years (IQR 35-45), 80.7% male. 67.8% patients knew their HIV-positive status before TB diagnosis, median time to TB diagnosis was 8 years (IQR 4-12). 83.6% were unemployed, 50.5%-anytime intravenous drug users (IDU), 34.9% abused alcohol. Drug-resistant TB rates in new and previously treated TB cases were 38.1% and 61.3%, respectively. In multivariable analysis, higher risk of drug-resistant TB was associated with imprisonment in new (aOR 3.35; 95%CI 1.17-9.57) and previously treated (aOR 6.63; 95%CI 1.09-40.35) cases. In 52.3% of new TB cases and in 42.5% previously treated TB cases the treatment outcomes were unsuccessful. In multivariable analysis of new TB cases, current imprisonment (aOR 2.77; 95%CI 1.29-5.91) and drug-resistant TB (aOR 2.18; 95%CI 1.11-4.28) were associated with unsuccessful treatment outcome. In multivariable analysis of previously treated TB cases, female gender (aOR 11.93; 95%CI 1.86-76.69), alcohol abuse (aOR 3.17; 95%CI 1.05-9.58), drug-resistant TB (aOR 4.83; 95%CI 1.53-15.28) were associated with unsuccessful treatment outcome.

CONCLUSIONS

In the TB-HIV-infected adult cohort in Lithuania, unemployment, imprisonment, IDU, alcohol abuse, known to be risk factors for TB, were very frequent. Drug resistance was an undeniable risk factor for unsuccessful treatment outcome and imprisonment was associated with drug resistant TB.

Tuberkulose im Erwachsenenalter

Die Tuberkulose ist in Deutschland eine seltene, überwiegend gut behandelbare Erkrankung. Weltweit ist sie eine der häufigsten Infektionserkrankungen mit ca. 10 Millionen Neuerkrankungen/Jahr. Auch bei einer niedrigen Inzidenz in Deutschland bleibt Tuberkulose insbesondere aufgrund der internationalen Entwicklungen und Migrationsbewegungen eine wichtige Differenzialdiagnose. In Deutschland besteht, aufgrund der niedrigen Prävalenz der Erkrankung und der damit verbundenen abnehmenden klinischen Erfahrung, ein Informationsbedarf zu allen Aspekten der Tuberkulose und ihrer Kontrolle. Diese Leitlinie umfasst die mikrobiologische Diagnostik, die Grundprinzipien der Standardtherapie, die Behandlung verschiedener Organmanifestationen, den Umgang mit typischen unerwünschten Arzneimittelwirkungen, die Besonderheiten in der Diagnostik und Therapie resistenter Tuberkulose sowie die Behandlung bei TB-HIV-Koinfektion. Sie geht darüber hinaus auf Versorgungsaspekte und gesetzliche Regelungen wie auch auf die Diagnosestellung und präventive Therapie einer latenten tuberkulösen Infektion ein. Es wird ausgeführt, wann es der Behandlung durch spezialisierte Zentren bedarf.

Die Aktualisierung der S2k-Leitlinie „Tuberkulose im Erwachsenenalter“ soll allen in der Tuberkuloseversorgung Tätigen als Richtschnur für die Prävention, die Diagnose und die Therapie der Tuberkulose dienen und helfen, den heutigen Herausforderungen im Umgang mit Tuberkulose in Deutschland gewachsen zu sein.

Regional distribution of Mycobacterium tuberculosis infection and resistance to rifampicin and isoniazid as determined by high-resolution melt analysis

Background

Identifying the transmission mode and resistance mechanism of Mycobacterium tuberculosis (MTB) is key to prevent disease transmission. However, there is a lack of regional data. Therefore, the aim of this study was to identify risk factors associated with the transmission of MTB and regional patterns of resistance to isoniazid (INH) and rifampicin (RFP), as well as the prevalence of multidrug-resistant tuberculosis (MDR-TB).

Methods

High-resolution melt (HRM) analysis was conducted using sputum, alveolar lavage fluid, and pleural fluid samples collected from 17,515 patients with suspected or confirmed MTB infection in the downtown area and nine counties of Luoyang City from 2019 to 2021.

Results

Of the 17,515 patients, 82.6% resided in rural areas, and 96.0% appeared for an initial screening. The HRM positivity rate was 16.8%, with a higher rate in males than females (18.0% vs. 14.1%, p < 0.001). As expected, a positive sputum smear was correlated with a positive result for HRM analysis. By age, the highest rates of MTB infection occurred in males (22.9%) aged 26–30 years and females (28.1%) aged 21–25. The rates of resistance to RFP and INH and the incidence of MDR were higher in males than females (20.5% vs. 16.1%, p < 0.001, 15.9% vs. 12.0%, p < 0.001 and 12.9% vs. 10.2%, p < 0.001, respectively). The HRM positivity rate was much higher in previously treated patients than those newly diagnosed for MTB infection. Notably, males at the initial screening had significantly higher rates of HRM positive, INH resistance, RFP resistance, and MDR-TB than females (all, p < 0.05), but not those previously treated for MTB infection. The HRM positivity and drug resistance rates were much higher in the urban vs. rural population. By multivariate analyses, previous treatment, age < 51 years, residing in an urban area, and male sex were significantly and positively associated with drug resistance after adjusting for smear results and year of testing.

Conclusion

Males were at higher risks for MTB infection and drug resistance, while a younger age was associated with MTB infection, resistance to INH and RFP, and MDR-TB. Further comprehensive monitoring of resistance patterns is needed to control the spread of MTB infection and manage drug resistance locally.

Contributory Factors to Successful Tuberculosis Treatment in Southwest Nigeria: A Cross-Sectional Study

Tuberculosis (TB) is one of the oldest human diseases, and preventing treatment failure is critical. This is because TB cases pose a risk to the immediate and remote communities due to the potential for spread, particularly for multidrug-resistant (MDR) strains that have been associated with higher morbidity and mortality rates. Hence, this study looked at the factors that influence TB treatment outcomes in Southwest Nigeria. We conducted a cross-sectional study with 712 TB patients from 25 directly observed treatment short course (DOTS) centers, out of which 566 (79.49%) were new treatment cases, and 102 (14.33%) were retreatment cases. The outcome variable was computed into successful treatment where ‘Yes’ was assigned to TB treatment completed and cured, and ‘No’ was assigned to all the remaining outcomes following the standard TB definition. Independent variables included in the analysis were the patient’s socio-demographic characteristics (such as age, sex, distance from the facility, marital status, family type, education, and computed socioeconomic status from modified DHS household assets), clinical and facility parameters (such as the HIV status, facility of access to healthcare, healthcare workers attitudes, services offered at the facility, appearance of the facility, number of people seeking care and waiting time at the facility). Bivariate analysis showed that HIV status (OR: 3.53, 95% CI: 1.83–6.82; p = 0.001), healthcare worker attitude (OR: 2.13, 95% CI: 1.21–3.74; p = 0.01), services offered at the facility (OR: 0.67, 95% CI: 0.49–0.92; p = 0.01), appearance of facility (OR: 0.67, 95% CI: 0.46–0.98; p = 0.04), and number of people seeking care (OR: 2.47, 95% CI: 1.72–3.55; p = 0.001) were associated with higher odds of successful treatment outcome with statistical significance. After multivariate analysis, reactive HIV status (aOR: 3.37, 95% CI: 1.67–6.80; p = 0.001), positive attitude of healthcare workers (aOR: 2.58, 95% CI: 1.36–4.89; p = 0.04), excellent services offered at the healthcare facility (aOR: 0.53, 95% CI: 0.36–0.78; p = 0.001) and few people seeking care (aOR: 2.10, 95% CI: 1.21–3.84; p = 0.001) became independent significant determinants of successful treatment outcome. The study concluded that reactive HIV status, positive attitude of healthcare workers, few people seeking healthcare, and excellent service provided were all factors that contributed to successful treatment outcomes.

Comprehensive genomic analysis of Mycobacterium tuberculosis reveals limited impact of high-fitness genotypes on MDR-TB transmission

OBJECTIVES

Environmental and host-related factors that contribute to the transmission of multidrug-resistant tuberculosis (MDR-TB) have become an increasing concern, but the impact of bacterial genetic factors associated with bacterial fitness on MDR-TB transmission is poorly understood. Here, we present a global view of the correlation between common fitness-related genotypes and MDR-TB transmission by analyzing a representative number of MDR-TB isolates.

METHODS

We assembled a global whole genome sequencing (WGS) dataset of MDR-TB strains collected through retrospective cohorts or population-based approaches using public databases and literature curation. WGS-based clusters were defined as groups of strains with genomic difference of ≤ 5 SNPs.

RESULTS

We curated high-quality WGS data of 4696 MDR-TB isolates from 17 countries with a mean clustering rate of 48% (range 0-100%). Correlational analysis showed that increased risk of MDR-TB strain clustering was not associated with compensatory mutations (OR 1.07, 95% CI 0.72-1.59), low-fitness cost drug-resistant mutations (katG S315T: OR 1.42, 95% CI 0.82-2.47; rpoB S450L: OR 1.26, 95% CI 0.87-1.83) or Lineage 2 (OR 1.50, 95% CI 0.95-2.39).

CONCLUSIONS

The factors most commonly thought to increase bacterial fitness were not significantly associated with increased MDR-TB transmission, and thus do not appear to be major contributors to the current epidemic of MDR-TB.

Detecting rifampin and isoniazid resistance in Mycobacterium tuberculosis direct from patient sputum using an automated integrated system

While there has been progress in detection of drug resistant tuberculosis globally, WHO estimates only about half of the patients with bacteriologically confirmed tuberculosis were tested for rifampicin resistance over the past two years. To close this drug resistance diagnostic gap, an expansion of testing for rifampicin and isoniazid resistance is critically needed. The Akonni Biosystem Integrated System combines DNA extraction and a Lab-on-a-Film assembly (LFA) to perform rapid probe and PCR-based detection of resistance associated mutations to first-line anti-tuberculosis drugs. Using raw sputum samples from 25 tuberculosis patients at risk for drug resistance, we conducted a proof-of-concept study of the Integrated System with an MDR-TB assay. Performance of the Integrated System was compared to liquid Mycobacteria Growth Indicator Tube (MGIT) culture reference phenotypes using 2012 WHO endorsed critical concentrations for rifampicin and isoniazid. The overall percent agreement for rifampicin and isoniazid was 91.7% and 100% respectively, with agreement for rifampicin increasing to 95.7% after low-level resistance mutations in rpoB were excluded. The Integrated System, combining DNA extraction and LFA amplification, is a promising new tool for detection of both rifampicin and isoniazid using liquefied raw sputum.

Treatment outcomes of patients with MDR-TB and its determinants at referral hospitals in Ethiopia

BACKGROUND

There is limited empirical evidence in Ethiopia on the determinants of treatment outcomes of patients with multidrug-resistant tuberculosis (MDR-TB) who were enrolled to second-line anti-tuberculosis drugs. Thus, this study investigated the determinants of treatment outcomes in patients with MDR-TB at referral hospitals in Ethiopia.

DESIGN AND METHODS

This study was underpinned by a cross-sectional quantitative research design that guided both data collection and analysis. Data is collected using structured questionnaire and data analyses was performed using the Statistical Package for Social Sciences. Multi-variable logistic regression was used to control for confounders in determining the association between treatment outcomes of patients with MDR-TB and selected predictor variables, such as co-morbidity with MDR-TB and body mass index.

RESULTS

From the total of 136 patients with MDR-TB included in this study, 31% had some co-morbidity with MDR-TB at baseline, and 64% of the patients had a body mass index of less than 18.5 kg/m2. At 24 months after commencing treatment, 76 (69%), n = 110), of the patients had successfully completed treatment, while 30 (27%) died of the disease. The odds of death was significantly higher among patients with low body mass index (AOR = 2.734, 95% CI: 1.01-7.395; P<0.048) and those with some co-morbidity at baseline (AOR = 4.260, 95%CI: 1.607-11.29; p<0.004).

CONCLUSION

The higher proportion of mortality among patients treated for MDR-TB at Adama and Nekemte Hospitals, central Ethiopia, is attributable to co-morbidities with MDR-TB, including HIV/AIDS and malnutrition. Improving socio-economic and nutritional support and provision of integrated care for MDR-TB and HIV/AIDS is recommended to mitigate the higher level of death among patients treated for MDR-TB.

Between Curing and Torturing: Burden of Adverse Reaction in Drug-Resistant Tuberculosis Therapy

Drug-resistant tuberculosis (DR-TB) requires prolonged and complex therapy which is associated with several adverse drug reactions (ADR). The burden of ADR can affect the quality of life (QoL) of patients that consists of physical, mental, and social well-being, and influences the beliefs and behaviors of patient related to treatment. This article reviews the burden of ADR and its association with QoL and adherence. We used PubMed to retrieve the relevant original research articles written in English from 2011 to 2021. We combined the following keywords: "tuberculosis," "Drug-resistant tuberculosis," "Side Effect," "Adverse Drug Reactions," "Adverse Event," "Quality of Life," "Adherence," "Non-adherence," "Default," and "Loss to follow-up." Article selection process was unsystematic. We included 12 relevant main articles and summarized into two main topics, namely, 1) ADR and QoL (3 articles), and 2) ADR and therapy adherence (9 articles). The result showed that patients with ADR tend to have low QoL, even in the end of treatment. Although it was torturing, the presence of ADR does not always result in non-adherence. It is probably because the perception about the benefit of the treatment dominates the perceived barrier. In conclusion, burden of ADR generally tends to degrade QoL of patients and potentially influence the adherence. A comprehensive support from family, community, and healthcare provider is required to help patients in coping with the burden of ADR. Nevertheless, the regimen safety and efficacy improvement are highly needed.

Comparative analysis of five inspection techniques for the application in the diagnosis and treatment of osteoarticular tuberculosis

OBJECTIVE

To evaluate five examination techniques in the diagnosis and treatment of osteoarticular tuberculosis (TB).

METHODS

Microbiological samples were collected from a total of 284 patients during the period August 2017 to December 2019 in Wuhan Pulmonary Hospital. The specimens were examined by acid-fast bacillus (AFB) smear microscopy, mycobacterial culture, PCR, T-SPOT.TB, and X-pert MTB/RIF rapid molecular detection.

RESULTS

The diagnostic sensitivity of the Xpert technology was 96.8% (116/120), specificity was 96.8% (58/60), the Youden index was 0.936, and the area under the receiver operating characteristic (ROC) curve was 0.967. The sensitivity and specificity of PCR were 84.2% (104/128) and 95.2% (76/80), respectively; the area under the ROC curve was 0.881. T-SPOT.TB had a detection sensitivity of 75.0% (12/16) and specificity of 85.0% (17/20). AFB smear microscopy had a sensitivity of 60.0% (75/125) and specificity of 95.8% (152/159). TB culture sensitivity was 58.1% (72/124) and specificity was 96.2% (73/76). The sensitivity and specificity of Xpert MTB/RIF for detecting rifampicin resistance were 100% (2/2) and 97.3% (73/75), respectively.

CONCLUSIONS

The Xpert MTB/RIF technique was found to have a good diagnostic value. With an additional diagnosis of Rifampicin resistance, it was also useful in tuberculosis therapy.

Effects of vancomycin linoleic acid nanoparticles on male reproductive indices of Sprague-Dawley rats

The management of bacterial infections, especially trains of methicillin-resistant Staphylococcus aureus observe in health care settings, has markedly improved with the introduction of established drugs but using newer nano-based formulations. This study investigates the effects of vancomycin-linoleic acid nanoparticles on testicular tissue in an experimental animal model. Twenty-five adult male Sprague-Dawley rats maintained at the Animal House of the Biomedical Resources Unit were assigned to five groups namely E - solid lipid nanoparticles; F - vancomycin solid lipid nanoparticle; G - linoleic acid nanoparticle; H - vancomycin linoleic acid; and A - control. Perturbations in seminal fluid parameters showed a reduced sperm count in groups F & G which was statistically significant (p < .05) but motility and morphology were not significant when compared to controls (A). Reduced testosterone levels were found in groups E, F and H but were not statistically significant (p > .05). There was also increased luteinizing hormone (LH) and decreased in follicular stimulating hormone (FSH) levels was statistically significant (p < .05). Hypoplasia, tubular atrophy and shrinkage were observed in histologic sections of the treated groups with basement membrane thickening. Vancomycin solid lipid nanoparticle and its constituents SLN and LA disrupted testicular morphometry and the hormonal milieu sufficient to potentially induce altered reproductive function.

National treatment outcome and predictors of death and treatment failure in multidrug-resistant tuberculosis in Ethiopia: a 10-year retrospective cohort study

OBJECTIVES

Treatment success rate in patients treated for multidrug-resistant tuberculosis (MDR-TB) is low, but predictors of treatment failure and death have been under-reported. Thus, we aimed to determine the national proportion of treatment success rate in the past 10 years and factors that predict treatment failure and death in patients with MDR-TB in Ethiopia.

SETTING

A retrospective cohort study with a 10-years follow-up period was conducted in 42 MDR-TB treatment-initiating centres in Ethiopia.

PARTICIPANTS

A total of 3395 adult patients with MDR-TB who had final treatment outcome and who were treated under national TB programme were included. Data were collected from clinical charts, registration books and laboratory reports. Competing risk survival analysis model with robust standard errors (SE) was used to determine the predictors of treatment failure and death.

PRIMARY AND SECONDARY OUTCOMES

Treatment outcome was a primary outcome whereas predictors of treatment failure and death were a secondary outcome.

RESULTS

The proportion of treatment success was 75.7%, death rate was 12.8%, treatment failure was 1.7% and lost to follow-up was 9.7%. The significant predictors of death were older age (adjusted hazard ratio (AHR)=1.03; 95% CI 1.03 to 1.05; p<0.001), HIV infection (AHR=2.0; 95% CI 1.6 to 2.4; p<0.001) and presence of any grade of anaemia (AHR=1.7; 95% CI 1.4 to 2.0; p<0.001). Unlike the predictors of death, all variables included into multivariable model were not significantly associated with treatment failure.

CONCLUSION

In the past 10 years, although MDR-TB treatment success in Ethiopia has been consistently favourable, the proportion of patients who died is still considerable. Death could be attributed to advanced age, HIV infection and anaemia. Prospective cohort studies are necessary to further explore the potentially modifiable predictors of treatment failure.

[MDR tuberculosis, Alpha-1-anti-trypsin Deficiency, Cough in a Geriatric Nurse]

Multidrug-resistant tuberculosis (MDR-TB) is of low proportion in comparison to the total number of TB patients, however, due to the necessity of a complex medication with potentially severe and life threatening adverse reactions, long term sequelae, and unfavorable outcome special attention is essential. We report the case of a 30-year-old geriatric nurse with a history of chronic cough and hereditary alpha-1-anti-trypsin deficiency (AATD), who suffered from MDR-TB and experienced a number of severe adverse reactions.

Additional Drug Resistance in Patients with Multidrug-resistant Tuberculosis in Korea: a Multicenter Study from 2010 to 2019

BACKGROUND

Drug-resistance surveillance (DRS) data provide key information for building an effective treatment regimen in patients with multidrug-resistant tuberculosis (MDR-TB). This study was conducted to investigate the patterns and trends of additional drug resistance in MDR-TB patients in South Korea.

METHODS

Phenotypic drug susceptibility test (DST) results of MDR-TB patients collected from seven hospitals in South Korea from 2010 to 2019 were retrospectively analyzed.

RESULTS

In total, 633 patients with MDR-TB were included in the analysis. Of all patients, 361 (57.0%) were new patients. All patients had additional resistance to a median of three anti-TB drugs. The resistance rates of any fluoroquinolone (FQ), linezolid, and cycloserine were 26.2%, 0.0%, and 6.3%, respectively. The proportions of new patients and resistance rates of most anti-TB drugs did not decrease during the study period. The number of additional resistant drugs was significantly higher in FQ-resistant MDR-TB than in FQ-susceptible MDR-TB (median of 9.0 vs. 2.0). Among 26 patients with results of minimum inhibitory concentrations for bedaquiline (BDQ) and delamanid (DLM), one (3.8%) and three (11.5%) patients were considered resistant to BDQ and DLM with interim critical concentrations, respectively. Based on the DST results, 72.4% and 24.8% of patients were eligible for the World Health Organization's longer and shorter MDR-TB treatment regimen, respectively.

CONCLUSION

The proportions of new patients and rates of additional drug resistance in patients with MDR-TB were high and remain stable in South Korea. A nationwide analysis of DRS data is required to provide effective treatment for MDR-TB patients in South Korea.

Toward a Phage Cocktail for Tuberculosis: Susceptibility and Tuberculocidal Action of Mycobacteriophages against Diverse Mycobacterium tuberculosis Strains

The global health burden of human tuberculosis (TB) and the widespread antibiotic resistance of its causative agent Mycobacterium tuberculosis warrant new strategies for TB control. The successful use of a bacteriophage cocktail to treat a Mycobacterium abscessus infection suggests that phages could play a role in tuberculosis therapy. To assemble a phage cocktail with optimal therapeutic potential for tuberculosis, we have explored mycobacteriophage diversity to identify phages that demonstrate tuberculocidal activity and determined the phage infection profiles for a diverse set of strains spanning the major lineages of human-adapted strains of the Mycobacterium tuberculosis complex. Using a combination of genome engineering and bacteriophage genetics, we have assembled a five-phage cocktail that minimizes the emergence of phage resistance and cross-resistance to multiple phages, and which efficiently kills the M. tuberculosis strains tested. Furthermore, these phages function without antagonizing antibiotic effectiveness, and infect both isoniazid-resistant and -sensitive strains.IMPORTANCE Tuberculosis kills 1.5 million people each year, and resistance to commonly used antibiotics contributes to treatment failures. The therapeutic potential of bacteriophages against Mycobacterium tuberculosis offers prospects for shortening antibiotic regimens, provides new tools for treating multiple drug-resistant (MDR)-TB and extensively drug-resistant (XDR)-TB infections, and protects newly developed antibiotics against rapidly emerging resistance to them. Identifying a suitable suite of phages active against diverse M. tuberculosis isolates circumvents many of the barriers to initiating clinical evaluation of phages as part of the arsenal of antituberculosis therapeutics.

Evaluation of drug-resistant tuberculosis treatment outcome in Portugal, 2000-2016

Treatment of drug-resistant tuberculosis (TB), which is usually less successful than that of drug-susceptible TB, represents a challenge for TB control and elimination. We aimed to evaluate treatment outcomes and to identify the factors associated with death among patients with MDR and XDR-TB in Portugal. We assessed MDR-TB cases reported for the period 2000-2016, using the national TB Surveillance System. Treatment outcomes were defined according to WHO recommendations. We identified the factors associated with death using logistic regression. We evaluated treatment outcomes of 294 MDR- and 142 XDR-TB patients. The treatment success rate was 73.8% among MDR- and 62.7% among XDR-TB patients (p = 0.023). The case-fatality rate was 18.4% among MDR- and 23.9% among XDR-TB patients. HIV infection (OR 4.55; 95% CI 2.31-8.99; p < 0.001) and resistance to one or more second-line injectable drugs (OR 2.73; 95% CI 1.26-5.92; p = 0.011) were independently associated with death among MDR-TB patients. HIV infection, injectable drug use, past imprisonment, comorbidities, and alcohol abuse are conditions that were associated with death early on and during treatment. Early diagnosis of MDR-TB and further monitoring of these patients are necessary to improve treatment outcome.

Multidrug- and Extensively Drug-Resistant Mycobacterium tuberculosis Beijing Clades, Ukraine, 2015

Multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) is an emerging threat to TB control in Ukraine, a country with the third highest XDR TB burden globally. We used whole-genome sequencing of a convenience sample to identify bacterial genetic and patient-related factors associated with MDR/XDR TB in this country. MDR/XDR TB was associated with 3 distinct Mycobacterium tuberculosis complex lineage 2 (Beijing) clades, Europe/Russia W148 outbreak, Central Asia outbreak, and Ukraine outbreak, which comprised 68.9% of all MDR/XDR TB strains from southern Ukraine. MDR/XDR TB was also associated with previous treatment for TB and urban residence. The circulation of Beijing outbreak strains harboring broad drug resistance, coupled with constraints in drug supply and limited availability of phenotypic drug susceptibility testing, needs to be considered when new TB management strategies are implemented in Ukraine.

In Vivo Imaging with Genetically Encoded Redox Biosensors

Redox reactions are of high fundamental and practical interest since they are involved in both normal physiology and the pathogenesis of various diseases. However, this area of research has always been a relatively problematic field in the context of analytical approaches, mostly because of the unstable nature of the compounds that are measured. Genetically encoded sensors allow for the registration of highly reactive molecules in real-time mode and, therefore, they began a new era in redox biology. Their strongest points manifest most brightly in in vivo experiments and pave the way for the non-invasive investigation of biochemical pathways that proceed in organisms from different systematic groups. In the first part of the review, we briefly describe the redox sensors that were used in vivo as well as summarize the model systems to which they were applied. Next, we thoroughly discuss the biological results obtained in these studies in regard to animals, plants, as well as unicellular eukaryotes and prokaryotes. We hope that this work reflects the amazing power of this technology and can serve as a useful guide for biologists and chemists who work in the field of redox processes.

Using Bayesian spatial models to map and to identify geographical hotspots of multidrug-resistant tuberculosis in Portugal between 2000 and 2016

Multidrug-resistant tuberculosis (MDR-TB) is a major threat to the eradication of tuberculosis. TB control strategies need to be adapted to the necessities of different countries and adjusted in high-risk areas. In this study, we analysed the spatial distribution of the MDR- and non-MDR-TB cases across municipalities in Continental Portugal between 2000 and 2016. We used Bayesian spatial models to estimate age-standardized notification rates and standardized notification ratios in each area, and to delimitate high- and low-risk areas, those whose standardized notification ratio is significantly above or below the country’s average, respectively. The spatial distribution of MDR- and non-MDR-TB was not homogeneous across the country. Age-standardized notification rates of MDR-TB ranged from 0.08 to 1.20 and of non-MDR-TB ranged from 7.73 to 83.03 notifications per 100,000 population across the municipalities. We identified 36 high-risk areas for non-MDR-TB and 8 high-risk areas for MDR-TB, which were simultaneously high-risk areas for non-MDR-TB. We found a moderate correlation (ρ = 0.653; 95% CI 0.457–0.728) between MDR- and non-MDR-TB standardized notification ratios. We found heterogeneity in the spatial distribution of MDR-TB across municipalities and we identified priority areas for intervention against TB. We recommend including geographical criteria in the application of molecular drug resistance to provide early MDR-TB diagnosis, in high-risk areas.

Multidrug-resistant Mycobacterium tuberculosis: a report of cosmopolitan microbial migration and an analysis of best management practices

Background

Tuberculosis (TB) control is a primary global health priority but the goal to eliminate TB is being threatened by the increase in incidence of multidrug-resistant tuberculosis (MDR-TB). With this series of seven MDR-TB cases in migrant patients with identical Mycobacterium tuberculosis strains we aim to illustrate the challenges encountered during therapy and follow-up: language barriers, access to care for migrant patients, depression due to isolation, adverse reactions to the treatment, management of pediatric TB, further contact tracing. We also discuss best practices for the management of complex MDR-TB cases in settings with low overall TB incidence focusing on modern diagnostic assays and an individualized and an interdisciplinary therapeutic approach.

Methods

We describe a case series of seven consecutively diagnosed MDR-TB patients, six of them treated at our tertiary care hospital between May 2018 and March 2020. Epidemiologic data was gained by semi-structured patient interviews and reconstruction of the migration route. The origin of the cluster was confirmed by genotyping of the TB-strains.

Results

Six related patients were diagnosed with pulmonary MDR-TB between May and August 2018. All had a positive Interferon-Gamma-Release Assay (IGRA), in five patients sputum microscopy was positive for acid-fast bacilli (AFB). The genetic and phenotypical drug susceptibility test did not match with MDR-TB strains from an East-African origin. The index patient was identified through genetical fingerprinting. By changing the therapy to a modern MDR-TB regime and using an interdisciplinary and culture-sensitive approach, all patients improved clinically and radiologically.

Conclusion

Human migration plays an important role for the global spread of MDR-TB in low incidence countries. Early case detection and adequate treatment are key to prevention of outbreaks. Especially language barriers and complex migration routes make genotyping of TB-strains a crucial tool to identify cases clusters, the potential index patient and transmission dynamics. We are fortunate enough to experience times in which new TB-antibiotics were made available and in which molecular assays revolutionized TB-diagnostics. We need to take advantage of that and develop personalized therapies for patients suffering from drug resistant TB.

Meta-analysis on Effectiveness and Safety of Moxifloxacin in Treatment of Multidrug Resistant Tuberculosis in Adults

BACKGROUND

Moxifloxacin, a fourth generation fluoroquinolone, which has good antibacterial activity against both Gram-positive cocci and Gram-negative bacteria. To date, there are no meta-analysis to evaluate the efficacy and safety of moxifloxacin for multi-drug resistant tuberculosis (MDR-TB) treatment. This meta-analysis to explore the efficacy and safety of the moxifloxacin in treatment of MDR-TB in adults.

METHODS

Databases of PubMed, Embase, Embase, Ovid, and Google Scholar databases were investigated for eligible literatures from their establishments to August, 2019. Included studies were selected according to precise eligibility criteria: MDR-TB confirmed by the clinical diagnostic criteria (at least 2 or more first-line drugs resistant to isoniazid and rifampicin). Study design was limited to retrospective studies, randomized controlled trials, or prospective cohort studies; the control group was treated with other drugs or no moxifloxacin. Statistical analysis was performed by RevMan 5.3 software.

RESULTS

Eight studies with a total of 1447 patients were finally eligible for the final systematic review and meta-analysis. Moxifloxacin regimen was related to a significantly elevated treatment success rate compared with levofloxacin or conventional therapy regimen (OR = 1.94; 95% CI = 1.16-3.25, P = .01). No significant difference of sputum culture conversion rate (OR = 1.15; 95% CI = 0.82-1.60; P = 0.43) was found between 2 groups. In addition, there was no significant difference in the increased risks of gastrointestinal trouble (OR = 1.28; 95% CI = 0.98-1.68; P = .05), hepatotoxicity (OR = 0.91; 95% CI = 0.64-1.30; P = .6), dermatologic abnormalities (OR = 1.11; 95% CI = 0.74-1.67; P = .62), and vision change (OR = 1.47; 95% CI = 0.74-2.89; P = .27) between the moxifloxacin-containing regimens and control group.

CONCLUSIONS

This meta-analysis revealed that the addition of moxifloxacin to the recommended regimen significantly improved the rate of treatment success in the treatment of MDR-TB, with no additional adverse moxifloxacin events.

Prospective evaluation of improving fluoroquinolone exposure using centralised therapeutic drug monitoring (TDM) in patients with tuberculosis (PERFECT): a study protocol of a prospective multicentre cohort study

INTRODUCTION

Global multidrug-resistant tuberculosis (MDR-TB) treatment success rates remain suboptimal. Highly active WHO group A drugs moxifloxacin and levofloxacin show intraindividual and interindividual pharmacokinetic variability which can cause low drug exposure. Therefore, therapeutic drug monitoring (TDM) of fluoroquinolones is recommended to personalise the drug dosage, aiming to prevent the development of drug resistance and optimise treatment. However, TDM is considered laborious and expensive, and the clinical benefit in MDR-TB has not been extensively studied. This observational multicentre study aims to determine the feasibility of centralised TDM and to investigate the impact of fluoroquinolone TDM on sputum conversion rates in patients with MDR-TB compared with historical controls.

METHODS AND ANALYSIS

Patients aged 18 years or older with sputum smear and culture-positive pulmonary MDR-TB will be eligible for inclusion. Patients receiving TDM using a limited sampling strategy (t=0 and t=5 hours) will be matched to historical controls without TDM in a 1:2 ratio. Sample analysis and dosing advice will be performed in a centralised laboratory. Centralised TDM will be considered feasible if >80% of the dosing recommendations are returned within 7 days after sampling and 100% within 14 days. The number of patients who are sputum smear and culture-negative after 2 months of treatment will be determined in the prospective TDM group and will be compared with the control group without TDM to determine the impact of TDM.

ETHICS AND DISSEMINATION

Ethical clearance was obtained by the ethical review committees of the 10 participating hospitals according to local procedures or is pending (online supplementary file 1). Patients will be included after obtaining written informed consent. We aim to publish the study results in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT03409315).

Pattern of infections in French and migrant homeless hospitalised at Marseille infectious disease units, France: A retrospective study, 2017-2018

BACKGROUND

No research has been conducted on the clinical characteristics and outcomes of homeless patients (HP) hospitalized in Infectious Disease Units (IDU).

METHODS

We conducted a retrospective survey among 98 HP and 98 non-HP admitted between 2017 and 2018 in several IDUs in Marseille, France.

RESULTS

HP were more likely to be migrant, to report frequent alcohol consumption or illicit drug use, and to present with respiratory symptoms at admission compared to controls. The most common final diagnoses in HP were respiratory tract infections (other than pulmonary tuberculosis [PTB], 35.7%), sexually transmitted infections (20.4%), cutaneous and mucosal infections (19.4%) and tuberculosis (12.2%). Sexually transmitted infections and ectoparasite infestations were significantly more frequent in HP compared to controls. One HP died from pleural effusion as a complication of PTB. The surviving HP had a longer length of stay (LOS, average 11.6 ± 13.6 days, p < 0.0001) than controls; independent factors of increased LOS were tobacco use (p = 0.009), tuberculosis infection (p < 0.0001), urinary tract infection (p = 0.018) and bacteraemia (p = 0.018). After hospital discharge, attendance at subsequent planned consultations was significantly lower in HP (0.72 ± 1.25 times/persons) compared to controls (2.03 ± 2.2).

CONCLUSIONS

We suggest that HP present specific demographic characteristics and patterns of infectious diseases compared to other patients and therefore require adapted management.

Calculated parenteral initial therapy of bacterial infections: Bacterial meningitis

This is the thirteenth chapter of the guideline "Calculated initial parenteral treatment of bacterial infections in adults - update 2018" in the 2^nd updated version. The German guideline by the Paul-Ehrlich-Gesellschaft für Chemotherapie e.V. (PEG) has been translated to address an international audience. Bacterial meningitis is a life-threatening infectious disease with high mortality and disability rates requiring prompt initiation of antimicrobial treatment to lower these rates.

MDR/XDR-TB management of patients and contacts: Challenges facing the new decade. The 2020 clinical update by the Global Tuberculosis Network

The continuous flow of new research articles on MDR-TB diagnosis, treatment, prevention and rehabilitation requires frequent update of existing guidelines. This review is aimed at providing clinicians and public health staff with an updated and easy-to-consult document arising from consensus of Global Tuberculosis Network (GTN) experts. The core published documents and guidelines have been reviewed, including the recently published MDR-TB WHO rapid advice and ATS/CDC/ERS/IDSA guidelines. After a rapid review of epidemiology and risk factors, the clinical priorities on MDR-TB diagnosis (including whole genome sequencing and drug-susceptibility testing interpretations) and treatment (treatment design and management, TB in children) are discussed. Furthermore, the review comprehensively describes the latest information on contact tracing and LTBI management in MDR-TB contacts, while providing guidance on post-treatment functional evaluation and rehabilitation of TB sequelae, infection control and other public health priorities.

Pharmacokinetic Modeling, Simulation, and Development of a Limited Sampling Strategy of Cycloserine in Patients with Multidrug-/Extensively Drug-Resistant Tuberculosis

BACKGROUND AND OBJECTIVE

Multidrug-resistant tuberculosis has much poorer treatment outcomes compared with drug-susceptible tuberculosis because second-line drugs for treating multidrug resistant tuberculosis are less effective and are frequently associated with side effects. Optimization of drug treatment is urgently needed. Cycloserine is a second-line tuberculosis drug with variable pharmacokinetics and thus variable exposure when programmatic doses are used. The objective of this study was to develop a population pharmacokinetic model of cycloserine to assess drug exposure and to develop a limited sampling strategy for cycloserine exposure monitoring.

MATERIAL AND METHODS

Patients with multidrug-/extensively drug-resistant tuberculosis who were treated for > 7 days with cycloserine were eligible for inclusion. Patients received cycloserine 500 mg (body weight ≤ 50 kg) or 750 mg (body weight > 50 kg) once daily. MW/Pharm 3.83 (Mediware, Groningen, The Netherlands) was used to parameterize the population pharmacokinetic model. The model was compared with pharmacokinetic values from the literature and evaluated with a bootstrap analysis, Monte Carlo simulation, and an external dataset. Monte Carlo simulations were used to develop a limited sampling strategy.

RESULTS

Cycloserine plasma concentration vs time curves were obtained from 15 hospitalized patients (nine male, six female, median age 35 years). Mean dose/kg body weight was 11.5 mg/kg (standard deviation 2.04 mg/kg). Median area under the concentration-time curve over 24 h (AUC_0-24 h) of cycloserine was 888 h mg/L (interquartile range 728-1252 h mg/L) and median maximum concentration of cycloserine was 23.31 mg/L (interquartile range 20.14-33.30 mg/L). The final population pharmacokinetic model consisted of the following pharmacokinetic parameters [mean (standard deviation)]: absorption constant K_{a_po} of 0.39 (0.31) h^-1, distribution over the central compartment (V_d) of 0.54 (0.26) L/kg LBM, renal clearance as fraction of the estimated glomerular filtration rate of 0.092 (0.038), and metabolic clearance of 1.05 (0.75) L/h. The population pharmacokinetic model was successfully evaluated with a bootstrap analysis, Monte Carlo simulation, and an external dataset of Chinese patients (difference of 14.6% and 19.5% in measured and calculated concentrations and AUC_0-24 h, respectively). Root-mean-squared-errors found in predicting the AUC_0-24 h using a one- (4 h) and a two- (2 h and 7 h) limited sampling strategy were 1.60% and 0.14%, respectively.

CONCLUSIONS

This developed population pharmacokinetic model can be used to calculate cycloserine concentrations and exposure in patients with multidrug-/extensively drug-resistant tuberculosis. This model was successfully validated by internal and external validation methods. This study showed that the AUC_0-24 h of cycloserine can be estimated in patients with multidrug-/extensively drug-resistant tuberculosis using a 1- or 2-point limited sampling strategy in combination with the developed population pharmacokinetic model. This strategy can be used in studies to correlate drug exposure with clinical outcome. This study also showed that good target attainment rates, expressed by time above the minimal inhibitory concentration, were obtained for cycloserine with a minimal inhibitory concentration of 5 and 10 mg/L, but low rates with a minimal inhibitory concentration of 20 and 32.5 mg/L.

Prevention and treatment of tuberculosis in solid organ transplant recipients

Introduction: Tuberculosis (TB) in solid organ transplant (SOT) recipients is associated with significant morbidity and mortality. Its management in transplant recipients is difficult and highly complex, given the underlying immunosuppression and the risks of drug-drug interactions imposed by immunosuppressive drugs that are needed to maintain the transplant allograft.Areas covered: We provide a brief review of TB in SOT and discuss the clinical indications, mechanisms of action and drug resistance, drug-drug interactions, and adverse effects of anti-TB drugs. We provide a summary of recent clinical trials, which serve as the foundation for current recommendations. We further include relevant updates on new agents being evaluated for clinical use in TB management.Expert commentary: TB causes significant morbidity in SOT recipients. The drugs used in the treatment for latent TB and active disease in SOT are similar to the regimens used in the general population. However, TB disease in transplant recipients is more difficult to manage because of the potential for hepatotoxicity and the complex drug-drug interactions with immunosuppressive drugs. We believe that alternative regimens suited for the vulnerable transplant population, and more therapeutic drug options are needed given the adverse toxicities associated with currently approved anti-TB drugs.

Impact of multidrug-resistant tuberculosis and its medications on adverse maternal and perinatal outcomes: protocol for a systematic review and meta-analysis

INTRODUCTION

Multidrug-resistant tuberculosis (MDR-TB) is a common public health problem affecting pregnant women. However, the impact of MDR-TB and its medication on pregnancy and perinatal outcomes has been poorly understood and inconsistently reported. Therefore, using the available literature, we aim to determine whether MDR-TB and its medications during pregnancy impact maternal and perinatal outcomes.

METHODS AND ANALYSIS

This systematic review and meta-analysis will adhere to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Systematic searches will be conducted in PubMed, Scopus and Web of Science on 10 February 2020 for studies that reported adverse maternal and perinatal outcomes due to MDR-TB and/or its medication. The search will be performed without language and time restrictions. Adverse birth outcomes include miscarriage or abortion, stillbirth, preterm birth, low birth weight, small and large for gestational age, and neonatal death. Two independent reviewers will screen search records, extract data and assess the quality of the studies. The Newcastle-Ottawa Quality Assessment Scale will be used to assess the methodological quality of the included studies. In addition to a narrative synthesis, a random-effects meta-analysis will be conducted when sufficient data are available. I² statistics will be used to assess the heterogeneity between studies.

ETHICS AND DISSEMINATION

As it will be a systematic review and meta-analysis based on previously published evidence, there will be no requirement for ethical approval. Findings will be published in a peer-reviewed journal and will be presented at various conferences.

Assessment of multidrug-resistant tuberculosis (MDR-TB) treatment outcomes in Sudan; findings and implications

Background: Multidrug-resistant tuberculosis (MDR-TB) has a socioeconomic impact and threatens global public health. We assessed treatment outcomes of MDR-TB and predictors of poor treatment outcomes in Sudan given current high prevalence rates.Methods: Combined retrospective and prospective cohort study at Abu-Anga hospital (TB specialized hospital in Sudan). All patients with MDR-TB between 2013 and 2017 were targeted.Results: A total of 156 patients were recruited as having good records, 117 (75%) were male, and 152 (97.4%) had pulmonary TB. Patients were followed for a median of 18 months and a total of 2108 person-months. The overall success rate was 63.5% and the mortality rate was 14.1%. Rural residency (P < 0.05) and relapsing on previous treatments (P < 0.05) were determinants of time to poor MDR-TB treatment outcomes.Conclusion: Overall, more attention needs to be given to special MDR-TB groups that are highly susceptible to poor outcomes, i.e. rural patients. As a result, it is highly recommended to maintain total coverage of medicines for all MDR-TB patients for the entire period of treatment in Sudan. It is also recommended to instigate more treatment centers in rural areas in Sudan together with programs to enhance adherence to treatments including patient counseling to improve future outcomes.

Systems thinking and ethics in public health: a necessary and mutually beneficial partnership

Systems thinking has emerged as a means of conceptualizing and addressing complex public health problems, thereby challenging more commonplace understanding of problems and corresponding solutions as straightforward explanations of cause and effect. Systems thinking tries to address the complexity of problems through qualitative and quantitative modeling based on a variety of systems theories, each with their own assumptions and, more importantly, implicit and unexamined values. To date, however, there has been little engagement between systems scientists and those working in bioethics and public health ethics. The goal of this paper is to begin to consider what it might mean to combine systems thinking with public health ethics to solve public health challenges. We argue that there is a role for ethics in systems thinking in public health as a means of elucidating implicit assumptions and facilitating ethics debate and dialogue with key stakeholders.

Comparison Of drrA And drrB Efflux Pump Genes Expression In Drug-Susceptible And -Resistant Mycobacterium tuberculosis Strains Isolated From Tuberculosis Patients In Iran

BACKGROUND

Among different resistance mechanisms in Mycobacterium tuberculosis (MTB), efflux pumps may have a role in drug-resistance property of MTB. So, the aim of this study was to compare the relative overexpression of two important efflux pump genes, drrA and drrB, among MTB isolates from TB patients.

METHODS

A total of 37 clinical isolates of confirmed MTB isolates were analyzed. Drug susceptibility testing (DST) was performed using the conventional proportional method. Real-time semiquantitative PCR profiling of the efflux pump genes of drrA and drrB was performed for clinical isolates. The receiver operating curve (ROC) analysis for differentiation of resistant from susceptible isolates on the basis of efflux pump expression fold changes was also performed.

RESULTS

According to DST, 16 rifampin (RIF) monoresistant, 3 isoniazid (INH) monoresistant, 5 multidrug-resistant (MDR) and 13 pan-susceptible isolates of MTB were evaluated for gene expression. The highest values of drrA and drrB gene expression fold changes were seen in MDR isolates, which were significant in comparison with susceptible isolates and H37Rv reference strain. By using comparative ROC analysis, the obtained cutoff point for drrA and drrB gene overexpression was the folds of >1.6 and >2.3, respectively.

CONCLUSION

The results of the present study confirm the role of DrrA-DrrB efflux pump in antibiotic resistance in clinical MTB isolates. As the large number of efflux pumps are located in the cell envelope of MTB, we cannot correlate a single efflux pump overexpression to the drug-resistance phenotype, unless all the pumps simultaneously investigated.

Hepatitis C virus infection: a challenge in the complex management of two cases of multidrug-resistant tuberculosis

Background

Multidrug-resistant tuberculosis (MDR-TB) requires lengthy use of second-line drugs, burdened by many side effects. Hepatitis C virus (HCV) chronic infection increases risk of drug-induced liver injury (DILI) in these patients. Data on MDR-TB patients with concurrent HCV chronic infection treated at the same time with second-line antitubercular drugs and new direct-acting antivirals (DAAs) are lacking. We evaluate if treating at the same time HCV infection and pulmonary MDR-TB is feasible and effective.

Cases presentation

In this study, we described two cases of patients with pulmonary MDR-TB and concurrent HCV chronic infection cured with DAAs at a Tertiary Infectious Diseases Hospital in Italy. During antitubercular treatment, both patients experienced a DILI before treating HCV infection.

After DAAs liver enzymes normalized and HCV RNA was undetectable. Then antitubercular regimen was started according to the institutional protocol, drawn up following WHO MDR-TB guidelines. It was completed without further liver side effects and patients were declared cured from both HCV infection and MDR-TB.

Conclusions

We suggest to consider treatment of chronic hepatitis C with DAAs as a useful intervention for reintroduction of second-line antitubercular agents in those patients who developed DILI, reducing the risk of treatment interruption when re-exposed to these drugs.

Association of genetic polymorphisms of CYP2E1, NAT2, GST and SLCO1B1 with the risk of anti-tuberculosis drug-induced liver injury: a systematic review and meta-analysis

OBJECTIVES

The objective of this study was to investigate the association between genetic polymorphisms of N-acetyltransferase 2 (NAT2), cytochrome P450 2E1 (CYP2E1), glutathione S-transferase (GST) and solute carrier organic anion transporter family member 1B1 (SLCO1B1) and the risk of anti-tuberculosis drug-induced liver injury (ATDILI).

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, Embase, Web of Science and Cochrane Reviews databases were searched through April 2019.

ELIGIBILITY CRITERIA

We included case-control or cohort studies investigating an association between NAT2, CYP2E1, GST or SLCO1B1 polymorphisms and the ATDILI risk in patients with tuberculosis.

DATA EXTRACTION AND SYNTHESIS

Three authors screened articles, extracted data and assessed study quality. The strength of association was evaluated for each gene using the pooled OR with a 95% CI based on the fixed-effects or random-effects model. Sensitivity analysis was performed to confirm the reliability and robustness of the results.

RESULTS

Fifty-four studies were included in this analysis (n=26 for CYP2E1, n=35 for NAT2, n=19 for GST, n=4 for SLCO1B1). The risk of ATDILI was significantly increased with the following genotypes: CYP2E1 RsaI/PstI c1/c1 (OR=1.39, 95% CI 1.06 to 1.83), NAT2 slow acetylator (OR=3.30, 95% CI 2.65 to 4.11) and GSTM1 null (OR=1.30, 95% CI 1.12 to 1.52). No significant association with ATDILI was found for the genetic polymorphisms of CYP2E1 DraI, GSTT1, GSTM1/GSTT1, SLCO1B1 388A>G and SLCO1B1 521T>C (p>0.05).

CONCLUSIONS

ATDILI is more likely to occur in patients with NAT2 slow acetylator genotype, CYP2E1 RsaI/PstI c1/c1 genotype and GSTM1 null genotype. Close monitoring may be warranted for patients with these genotypes.

A nationwide study of multidrug-resistant tuberculosis in Portugal 2014-2017 using epidemiological and molecular clustering analyses

Background

Increasing multidrug-resistant tuberculosis (MDR-TB) incidence is a major threat against TB eradication worldwide. We aim to conduct a detailed MDR-TB study in Portugal, an European country with endemic TB, combining genetic analysis and epidemiological data, in order to assess the efficiency of public health containment of MRD-TB in the country.

Methods

We used published MIRU-VNTR data, that we reanalysed using a phylogenetic analysis to better describe MDR-TB cases transmission occurring in Portugal from 2014 to 2017, further enriched with epidemiological data of these cases.

Results

We show an MDR-TB transmission scenario, where MDR strains likely arose and are transmitted within local chains. 63% of strains were clustered, suggesting high primary transmission (estimated as 50% using MIRU-VNTR data and 15% considering epidemiological links). These values are higher than those observed across Europe and even for sensitive strains in Portugal using similar methodologies. MDR-TB cases are associated with individuals born in Portugal and evolutionary analysis suggests a local evolution of strains. Consistently the sublineage LAM, the most common in sensitive strains in Europe, is the more frequent in Portugal in contrast with the remaining European MDR-TB picture where immigrant-associated Beijing strains are more common.

Conclusions

Despite efforts to track and contain MDR-TB strains in Portugal, their transmission patterns are still as uncontrolled as that of sensitive strains, stressing the need to reinforce surveillance and containment strategies.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-4189-7) contains supplementary material, which is available to authorized users.

Towards tailored regimens in the treatment of drug-resistant tuberculosis: a retrospective study in two Italian reference Centres

Background

The increased incidence of drug-resistant TB is a major challenge for effective TB control. Limited therapeutic options and poor treatment outcomes of DR-TB may increase drug-resistance rates. The objective of the study is to retrospectively compare MDR-TB and pre-XDR-TB treatment regimens and outcomes in two large TB reference centres in Italy from January 2000 to January 2015.

Methods

A retrospective, multicentre study was conducted at the Regional TB Reference Centre Villa Marelli Institute (Milan) and at the Reference Center for MDR-TB and HIV-TB, Eugenio Morelli Hospital (Sondalo). The supra-national Reference Laboratory in Milan performed DST. Inclusion criteria were: age ≥ 18 and culture-confirmed diagnosis of MDR- or pre-XDR TB. Chi-square or Fisher exact test was used to detect differences in the comparison between treatment outcomes, therapeutic regimens, and drug-resistances. Computations were performed with STATA 15.

Results

A total of 134 patients were selected. Median (IQR) age at admission was 33 (26–41) years and 90 patients (67.2%) were male. Pulmonary TB was diagnosed in 124 (92.5%) patients. MDR- and pre-XDR-TB cases were 91 (67.9%) and 43 (32.1%), respectively. The WHO shorter MDR-TB regimen could have been prescribed in 16/84 (19.1%) patients. Treatment success was not statistically different between MDR- and pre-XDR-TB (81.3% VS. 81.4%; P = 0.99). Mortality in MDR-TB and pre-XDR-TB groups was 4.4 and 9.3%, respectively (P = 0.2). Median duration of treatment was 18 months and a total of 110 different regimens were administered. Exposure to linezolid, meropenem, and amikacin was associated with a better outcome in both groups (P = 0.001, P < 0.001, and P = 0.004, respectively).

Conclusions

Tailored treatment regimens based on DST results can achieve successful outcomes in patients with pre-XDR-TB.