The burden of multidrug-resistant tuberculosis in children

Determinants of treatment outcome in children with multidrug-resistant tuberculosis: a tertiary care hospital experience

This study aimed to analyze the significant factors associated with unsuccessful treatment outcomes among multidrug-resistant tuberculosis in children under 18. This observational study was conducted at the Bahawal Victoria Hospital, Bahawalpur, Pakistan, at the Programmatic Management Unit of the National Tuberculosis Control Program of Pakistan. The data were collected retrospectively using the Electronic Nominal Recording Reporting System records for all the eligible drug-resistant tuberculosis patients registered at the study sites between June 2014 and September 2022. Multivariate binary logistic regression analysis was used to analyze the factors significantly associated with unsuccessful treatment outcomes. This study included 88 children. Of the 88 patients, 64 (72.8%) completed their treatment successfully. A total of 13 patients (14.8%) died, 2 (2.3%) had treatment failure, and 9 (10.2%) were lost to follow-up. Factors significantly associated with unsuccessful treatment outcomes included a history of use of second-line drugs and those with favorable interim treatment outcomes (negative association). The overall treatment success rate among the children was 72.8%, which can be further improved by reducing loss to follow-up and rational use of second-line drugs in treating drug-sensitive tuberculosis. This can be done by devising a careful, targeted treatment regimen and patient education.

Experiences of children and their caregivers affected by multidrug-resistant tuberculosis in Cape Town, South Africa

BACKGROUND

Approximately 30,000 children (<15 years) develop multidrug-resistant (MDR) tuberculosis (TB) each year. MDR-TB severely impacts the lives of children and their families, yet data exploring their experiences are limited. We describe the experiences of children routinely treated for MDR-TB and their caregivers throughout their MDR-TB journeys in Cape Town, South Africa.

METHODS

We conducted a series of three in-depth qualitative interviews (48 interviews in total) with 17 children (<15 years) and/or their caregivers between April 2021 and September 2021. We selected children who had been routinely treated for MDR-TB between 2018 and 2021. We applied a deductive, thematic analysis to case summaries with illustrative examples from interviews.

FINDINGS

Children had negative experiences throughout their MDR-TB journey, before their diagnosis, during the diagnostic process, through treatment, and beyond treatment completion. Children and their caregivers experienced delays in acquiring accurate and timely MDR-TB diagnosis; stating lack of symptom recognition and repeated referrals between health facilities. Once on treatment, caregivers experienced challenges administering MDR-TB medication as children resisted taking their medications due to poor palatability, tolerability, and negative side effects. Some caregivers reported that, beyond treatment, children experienced extended physical challenges such as shortness of breath. Additionally, MDR-TB diagnosis and treatment negatively affected family life, as caregivers adjusted household spending toward foods that facilitated ingestion and mitigated side effects. Caregivers also juggled between attending to their children's MDR-TB care and other household priorities.

CONCLUSION

There are multifactorial challenges experienced by children and their caregivers throughout their MDR-TB journey. Research is needed to develop holistic interventions for child-caregiver-centred psychosocial support to mitigate the negative impact of MDR-TB on children and their caregivers through prevention, earlier diagnosis, and simpler, child-friendly regimens. [1112,3].

Model-Informed Once-Daily Dosing Strategy for Bedaquiline and Delamanid in Children, Adolescents and Adults with Tuberculosis

The complexity of the currently registered dosing schedules for bedaquiline and delamanid is a barrier to uptake in drug-resistant tuberculosis treatment across all ages. A simpler once-daily dosing schedule is critical to ensure patient-friendly regimens with good adherence. We assessed expected drug exposures with proposed once-daily doses for adults and compared novel model-informed once-daily dosing strategies for children with current World Health Organization (WHO) recommended dosing. A reference individual and virtual pediatric population were generated to simulate exposures in adults and children, respectively. Published population models characterizing the exposures of bedaquiline and its metabolite M2, delamanid, and its metabolite DM-6705 were utilized. During simulation, child growth during treatment along with several CYP3A4 ontogeny profiles was accounted for. Exposures in children were compared with simulated adult targets to assess the expected treatment efficacy and safety. In adults, the proposed bedaquiline once-daily dosing (400 mg daily for 2 weeks followed by 100 mg daily for 22 weeks) yielded 14% higher exposures of bedaquiline and M2 compared to the labeled dosing scheme at 24 weeks; for delamanid and DM-6705, the suggested 300 mg daily dose provided 13% lower exposures at steady state. For children, the cumulative proportions of exposures of both drugs showed < 5% difference between WHO-recommended and proposed once-daily dosing. This study demonstrated the use of model-informed approaches to propose rational and simpler regimens for bedaquiline and delamanid in adults and children. The new once-daily dosing strategies will be tested in the PARADIGM4TB and IMPAACT 2020 trials in adults and children, respectively.

Treatment of pre-extensively drug-resistant tuberculosis in a 4-month-old infant using a regimen of bedaquiline, delamanid, and contezolid

Drug-resistant tuberculosis (TB) is a significant global challenge, especially in children, where diagnosis and treatment are difficult. This report describes a 4-month-old male infant with pre-extensively drug-resistant tuberculosis (pre-XDR-TB) successfully treated with bedaquiline, delamanid, and contezolid. The patient, born prematurely, developed severe pulmonary TB after exposure to drug-resistant TB from the mother. After discontinuing the initial regimen due to adverse effects, the adjusted regimen resulted in negative TB culture conversion, significant pulmonary improvement, and no notable adverse effects.

Chest X-Ray Features of Drug Resistance Tuberculosis in Pediatric Population; A Prospective Study in High-Endemic Area

OBJECTIVE

To identify chest X-ray (CXR) characteristic of Pediatric pulmonary drug-resistant tuberculosis (DRTB) in comparison to drug sensitive tuberculosis (DSTB) for early identification and treatment of DRTB.

METHODS

This was a prospective cross-sectional study in which CXR patterns of DS and DR patients aged 1 month to 18 years were categorized into different variants including pleural effusion, cavity lesion, hilar or mediastinal lymph node (LN), consolidation, pneumothorax, pericardial effusion, miliary TB, nodular shadow, and collapse. The consensus between the pulmonary physician and radiologist was measured using weighted kappa test. Adjusted logistic regression analysis was used to identify DRTB suggestive CXR pattern.

RESULTS

From June 1, 2022 to May 31, 2023, 237 pulmonary TB subjects were recruited. Out of 175 DSTB subjects, 47 were below the age of 12 and 128 were above the age of 12. 62 were microbiologically confirmed DRTB where 12 were below the age of 12 and 50 were above the age of 12. Cavitary TB lesions (p = 0.001) and Consolidation (p = 0.003) were found significant in DR patients. Adjusting for age, gender, socioeconomic status DRTB was associated with cavity lesion (OR = 2.62; 95% CI = 1.39-4.93; p = 0.001) and consolidation (OR = 2.29; 95% CI = 1.27-4.14; p = 0.003).

CONCLUSION

We conclude that presence of cavitary lesion or consolidation in "presumptive" or "probable" DRTB patients should alert pediatricians. Our findings suggest that these DR suggestive CXR pattern can guide for early start of therapy while awaiting microbiological report.

Population pharmacokinetics and dosing of dispersible moxifloxacin formulation in children with rifampicin-resistant tuberculosis

AIMS

Moxifloxacin is a priority drug for treating rifampicin-resistant tuberculosis (RR-TB). We assessed the pharmacokinetics of a child-friendly, dispersible 100 mg tablet moxifloxacin formulation (dispersed in water) compared to the standard 400 mg non-dispersible formulation (crushed and suspended in water) in children and evaluated current dosing recommendations.

METHODS

The CATALYST trial investigated the pharmacokinetics of moxifloxacin in children with RR-TB. Children were enrolled in South Africa, India and the Philippines. Intensive pharmacokinetic sampling was undertaken while children were taking the standard non-dispersible 400 mg moxifloxacin tablet formulation and repeated after switching to the novel dispersible formulation. Pharmacokinetic data were analysed using population pharmacokinetic modelling. Simulations were performed to evaluate moxifloxacin exposures in children compared to consensus adult reference exposures using current World Health Organization (WHO)-recommended doses and more recent model-based doses.

RESULTS

Thirty-six children were enrolled [median age 4.8 (range 0.4-15) years and weight 15.6 (range 6.9-42.1) kg]. A two-compartment disposition model with first-order elimination and delayed absorption was developed. The bioavailability of dispersible versus standard formulations fulfilled standard bioequivalence criterion (ratio 1.05 with 90% confidence interval 0.95-1.15). Simulations showed WHO-recommended doses achieved exposures similar to those in adults in children >10 kg, while children <10 kg may require 33%-56% higher doses to reach adult reference exposures.

CONCLUSIONS

Dosing recommendations for children can be the same for the dispersible paediatric and standard non-dispersible adult moxifloxacin formulation. The current WHO dosing recommendation risks underdosing moxifloxacin in children <10 kg. We propose optimized moxifloxacin doses for both formulations.

Treatment outcomes among children and adolescents with extensively drug-resistant (XDR) and pre-XDR tuberculosis: Systematic review and meta-analysis

Extensively drug-resistant (XDR) and pre-XDR- tuberculosis (TB) account for approximately a third of pediatric MDR-TB cases globally. Clinical management is challenging; recommendations are based on limited evidence. We assessed the clinical outcomes for children and adolescents treated for XDR-and pre-XDR-TB. We performed a systematic review and meta-analysis of published studies reporting treatment outcomes for children and adolescents with XDR-and pre-XDR-TB. MEDLINE, EMBASE, Scopus, Web of Science, Google Scholar, and trial registries up to 31 December 2023 were searched. Eligible studies included children and adolescents aged <18 years with XDR-or pre-XDR-TB. The primary outcome was treatment success, defined as a composite of cure and treatment completion. Secondary outcomes were death, failure/ lost to follow-up and adverse events. We identified 34 population-based studies and 14 case studies, which reported treatment outcomes for a total of 656 patients. Treatment durations ranged from 6 to 27 months; follow-up after treatment completion ranged from 2 months to 4 years. The pooled estimate for treatment success in XDR-and pre-XDR-TB was 88·9% (95%CI: 59·7-100%) and 65·4% (95%CI: 27·7-100%), respectively. Drug adverse effects were reported in 56.4% (95%CI: 9.9-100%) and 68.2% (95%CI: 0-100%) of children respectively. Few childhood XDR- and pre-XDR-TB cases are reported. The relatively good treatment outcomes in children compared to adults may be partly due to publishing bias. Drug adverse effects are common.

Wealth-based inequalities in tuberculosis prevalence among households having children and young adults in India: insights from Indian demographic and health surveys (2015-2021)

BACKGROUND

Tuberculosis (TB) remains a significant health concern in India, especially among households with children and young adolescents aged 6-17 years. Despite ongoing research, there is a knowledge gap regarding specific risk factors for TB within this demographic. This study aims to bridge this gap by examining the association between TB and various socio-demographic factors, including socioeconomic status, nutritional status, and environmental conditions.

DATA AND METHODS

Utilizing data from the National Family Health Survey (NFHS) 4th and 5th round (2015-16 and 2019-21), this study conducted a comprehensive cross-sectional analysis. Unadjusted and Adjusted Logistic regression is utilized to identify key factors influencing TB. Furthermore, Wagstaff decomposition analysis is applied, to quantifying the factors that contributes to the inequalities in social determinants on the wealth-related inequality observed in the prevalence of TB.

RESULTS

The study observed a notable decline in TB prevalence from 1.7 to 1.2% among individuals from households having children and young adolescents aged 6-17 years. Additionally, factors like the use of unclean cooking fuel, lack of electricity, and unimproved toilet facilities were associated with increased TB prevalence. Wealth-based inequality in TB prevalence was also evident, with the burden falling disproportionately on poorer households. Unclean fuel is the most significant determinant of wealth-based inequality in TB, contributing to nearly 2/5th (18.5% in NFHS-4) of the observed inequality. Notably, gender did not significantly influence TB prevalence.

CONCLUSION

The decline in TB prevalence in India correlates with improvements in socio-economic and living conditions, as evidenced by increased access to better housing, clean fuel, and sanitation facilities. The study underscores the need for integrated public health strategies that address both medical and socio-environmental determinants of TB. Improving socio-economic conditions, alongside targeted healthcare interventions, appears vital in reducing the TB burden in high-prevalence settings like India. This research emphasizes the importance of comprehensive approaches to combat pediatric TB, combining clinical care with enhancements in living standards and access to basic amenities.

Effect of integrating paediatric tuberculosis services into child healthcare services on case detection in Africa: the INPUT stepped-wedge cluster-randomised trial

INTRODUCTION

Paediatric tuberculosis (TB) underdiagnosis is a critical concern. The INPUT stepped-wedge cluster-randomised trial assessed the impact of integrating child TB services into child healthcare on TB case detection among children under age 5 years.

METHODS

We compared the standard of care, providing TB care in specific TB clinics (control phase), with the Catalysing Paediatric TB Innovations (CaP-TB) intervention, integrating TB services across all child health services (intervention phase). 12 clusters in Cameroon and Kenya transitioned from the standard of care to the intervention at randomly assigned times. Children with presumptive TB were enrolled after obtaining their parents' consent and were followed throughout TB diagnostic procedures and treatment. Study outcomes included the rate of children with presumptive TB receiving TB investigations and that of children diagnosed with TB (the primary outcome was case detection), per thousand children under 5 years attending facilities. Generalised linear mixed Poisson models estimated the intervention's effect as adjusted rate ratios (aRR) and associated 95% CIs. Ad hoc country-stratified analyses were conducted.

RESULTS

During control and intervention phases, respectively, 121 909 and 109 614 children under 5 years attended paediatric entry points, 133 (1.1 per thousand) and 610 (5.6 per thousand) children with presumptive TB received TB investigations, and 79 and 74 were diagnosed with TB, corresponding to a case detection rate of 0.64 and 0.68 per thousand, respectively. CaP-TB significantly increased TB investigations in both countries overall (aRR=3.9, 95% CI 2.4 to 5.4), and in each. Overall, TB case detection was not statistically different between intervention and control (aRR 1.32, 95% CI 0.66 to 2.61, p=0.43). Country-stratified analysis revealed a 10-fold increase (aRR 9.75, 95% CI 1.04 to 91.84, p=0.046) in case detection with CaP-TB in Cameroon and no significant effect in Kenya (aRR 0.94, 95% CI 0.44 to 2.01, p=0.88).

CONCLUSION

CaP-TB increased TB investigations in both study countries and markedly enhanced TB case detection in one, underlining integrated TB services' potential to address paediatric TB underdiagnosis.

Linezolid Pharmacokinetic-Anemia Modeling in Children With Rifampicin-Resistant Tuberculosis

BACKGROUND

Linezolid, a component of rifampicin-resistant/multidrug-resistant tuberculosis (RR/MDR-TB) treatment, is associated with treatment-limiting toxicities, including anemia. Patient-level and linezolid pharmacokinetic risk factors for anemia have not been well described in children treated for RR/MDR-TB.

METHODS

We evaluated the pharmacokinetics of linezolid and longitudinal hemoglobin data to validate an existing population linezolid pharmacokinetic model. We assessed the impact of linezolid pharmacokinetics and the risk of developing anemia in a prospectively enrolled cohort of children. A previously published population pharmacokinetic linezolid model was validated using nonlinear mixed effects modeling. A multivariable ordinal logistic regression model was built to predict the incidence of anemia.

RESULTS

A total of 112 children, median age 7.2 years (interquartile range, 2.2-16.3), were included from South Africa (n = 87) and India (n = 25). Of these, 24 children contributed new linezolid pharmacokinetic data. The population pharmacokinetic model, which informs the currently recommended linezolid dosing in children (10-15 mg/kg), was validated with these additional new data. For every 1 g/dL lower baseline hemoglobin level, the odds of developing grade 3 or 4 anemia increased by 2.64 (95% confidence interval [CI], 1.98-3.62). For every 1 mg/L × h higher linezolid area under the concentration-time curve, the odds of developing grade 3 or 4 anemia increased by 1.012 (95% CI, 1.007-1.017).

CONCLUSIONS

Taken together, these data confirm currently recommended linezolid doses for children. The risk of anemia in children should be carefully considered and monitored. Initiating linezolid in children with low baseline hemoglobin increases the probability of experiencing grade 3 or 4 anemia.

Drug-resistant tuberculosis: a persistent global health concern

Drug-resistant tuberculosis (TB) is estimated to cause 13% of all antimicrobial resistance-attributable deaths worldwide and is driven by both ongoing resistance acquisition and person-to-person transmission. Poor outcomes are exacerbated by late diagnosis and inadequate access to effective treatment. Advances in rapid molecular testing have recently improved the diagnosis of TB and drug resistance. Next-generation sequencing of Mycobacterium tuberculosis has increased our understanding of genetic resistance mechanisms and can now detect mutations associated with resistance phenotypes. All-oral, shorter drug regimens that can achieve high cure rates of drug-resistant TB within 6-9 months are now available and recommended but have yet to be scaled to global clinical use. Promising regimens for the prevention of drug-resistant TB among high-risk contacts are supported by early clinical trial data but final results are pending. A person-centred approach is crucial in managing drug-resistant TB to reduce the risk of poor treatment outcomes, side effects, stigma and mental health burden associated with the diagnosis. In this Review, we describe current surveillance of drug-resistant TB and the causes, risk factors and determinants of drug resistance as well as the stigma and mental health considerations associated with it. We discuss recent advances in diagnostics and drug-susceptibility testing and outline the progress in developing better treatment and preventive therapies.

Including the voice of children <15-years-old in paediatric global health research

Purpose of Review

Despite evidence of the benefits of including children's voices in global health research, they continue to be underrepresented. Implementation of how to include children's voices appears to remain an obstacle to their inclusion in global health research. In this manuscript, we present an epistemological frame that advocates children as experts of their own experiences and knowledge-bearers. Then we provide four case studies, to illustrate ongoing efforts to build equity in the design and execution of paediatric health research.

Recent Findings

Ensuring children's equitable inclusion requires recognizing them as active participants in their health and wellbeing, and empowering them to employ their agency in all interactions with researchers, while recognizing the dialogical nature of those interactions. Successfully involving children in global health research can lead to important psychosocial and clinical insights, that could be leveraged to inform future treatment and care practices.

Summary

We present four case studies describing the inclusion of children in research and research development related to prevention, treatment and/or care of chronic and acute diseases (tuberculosis, HIV, cervical and other forms of cancer) in a number of global settings including India, Philippines, South Africa, United States, Zambia. The exemplars detail novel applications of a diversity of arts-based methods that are rooted in frameworks for participatory action research. They highlight the need to invest funds, training, time and resources for early and sustained engagement with children throughout the research process. We conclude by offering principles for equitably engaging children in global health research.

Current Treatment of Drug-Resistant Tuberculosis in Children

Optimal diagnosis and management of children aged <15 y with rifampicin- or multidrug-resistant tuberculosis (RR/MDR-TB) relies on identification of adults with the disease and pro-active screening of their close contacts. Children may be diagnosed with RR/MDR-TB based on microbiological confirmation from clinical specimens (sputum, gastric washings, stool), but usually the diagnosis is presumptive, with a history of exposure to RR/MDR-TB and clinical/radiological signs and symptoms suggestive of TB disease. RR/MDR-TB should also be considered in children where first-line TB treatment fails despite good adherence to therapy. Composition and duration of all-oral RR/MDR-TB treatment regimens in children are based on site and severity of TB disease, drug resistance profile of the Mycobacterium tuberculosis strain (isolated from the child or from the most likely source patient), inclusion of at least four drugs considered to be effective (with priority given to World Health Organization Group A and B drugs), toxicity and tolerability of medications (and feasibility of adverse effect monitoring in the child's setting), and availability of child-friendly formulations of TB medications. Individualized RR/MDR-TB regimens are preferable to the standardised 9-12-mo regimen for children, and injectable agents must not be used. Optimal adherence to treatment relies on education, training and support for caregivers and others who are responsible for administering medications to children, as well as close clinical monitoring and early management of adverse effects. Children who are initiated on adequate RR/MDR-TB regimens have high treatment success rates, but efforts to find and treat more children with undiagnosed RR/MDR-TB are crucial to reduce childhood TB mortality.

Multidrug-resistant tuberculosis in children: A practical update on epidemiology, diagnosis, treatment and prevention

Pediatric multidrug-resistant tuberculosis (MDR-TB) remains a significant global problem, and there are numerous barriers preventing children with MDR-TB from being identified, confirmed with microbiologic tests, and treated with a safe, practical, and effective regimen. However, several recent advances in diagnostics and treatment regimens have the promise to improve outcomes for children with MDR-TB. We introduce this review with two cases that exemplify both the challenges in management of MDR-TB in children, but also the potential to achieve a positive outcome. More than 30,000 cases of MDR-TB per year are believed to occur in children but less than 5% are confirmed microbiologically, contributing to poorer outcomes and excess mortality. Rapid molecular-based testing that provides information on rifampin susceptibility is increasingly globally available and recommended for all children suspected of TB disease--but remains limited by challenges obtaining appropriate samples and the paucibacillary nature of most pediatric TB. More complex assays allowing better characterization of drug-resistant isolates are emerging. For children diagnosed with MDR-TB, treatment regimens have traditionally been long and utilize multiple drugs associated with significant side effects, particularly injectable agents. Several new or repurposed drugs including bedaquiline, delamanid, clofazimine and linezolid now allow most treatment regimens to be shorter and all-oral. Yet data to support short, all-oral, novel regimens for young children containing pretomanid remain insufficient at present, and there is a compelling need to conduct pediatric trials of promising therapeutics and MDR-TB treatment regimens.

Pharmaceutical cost dynamics for the treatment of rifampicin-resistant tuberculosis in children and adolescents in South Africa, India, and the Philippines

Rifampicin-resistant (RR) tuberculosis (TB) in children is a major global health concern but is often neglected in economics research. Accurate cost estimations across the spectrum of paediatric RR-TB treatment regimens are critical inputs for prioritisation and budgeting decisions, and an existing knowledge gap at local and international levels. This normative cost analysis was nested in a Phase I/II pharmacokinetics, safety, tolerability, and acceptability trial of TB medications in children in South Africa, the Philippines and India. It assessed the pharmaceutical costs of 36 childhood RR-TB regimens using combinations from 16 different medicines in 34 oral formulations (adult and child-friendly) in 11 weight bands in children <15 years of age. The analysis used local and Global Drug Facility pricing, and local and international guideline recommendations, including adaptions of BPaL and BPaLM regimens in adults. Costs varied significantly between regimen length, age/weight banding, severity of disease, presence of fluroquinolone resistance, and different country guideline recommendations. WHO recommended regimen costs ranged 12-fold: from US$232 per course (short regimen in non-severe disease) to US$2,761 (long regimen in severe, fluroquinolone-resistant disease). Regimen treating fluoroquinolone-resistant infection cost US$1,090 more than comparable WHO-recommended regimen. Providing child-friendly medicine formulations in <5-year-olds across all WHO-recommended regimens is expected to cost an additional $380 (range $212-$563) per child but is expected to have wider benefits including palatability, acceptability, adherence, tolerability, and dose accuracy. There were substantial differences in regimen affordability between countries when adjusted for purchasing power and domestic spending on health. Appropriate, effective, and affordable treatment options are an important component of the fight against childhood RR-TB. A comprehensive understanding of the cost and affordability dynamics of treatment options will enable national TB programs and global collaborations to make the best use of limited healthcare resources for the care of children with RR-TB.

Holistic acceptability of an adult levofloxacin formulation in children and adolescents on a tuberculosis preventive treatment trial

Drug-resistant tuberculosis (TB) is threatening global TB control. Although formulations designed for children are a priority, adult levofloxacin formulations are widely used in TB treatment and prevention. TB-CHAMP was a cluster-randomised, placebo-controlled trial evaluating the efficacy and safety of 24 weeks of daily levofloxacin to prevent TB in child and adolescent household contacts of adults with infectious multidrug-resistant TB. Nested in-depth longitudinal qualitative work was conducted in a subset of children and their caregivers to understand broader experiences of treatment acceptability. We conducted 41 interviews with 8 caregivers of children <6 years, and with 6 older children responding for themselves. Children who could not swallow the adult formulation whole, found the tablet unpalatable, although they learnt to tolerate the taste over time. Most caregivers and children came from families with substantial experience of TB, but felt they knew little about TB preventive therapy. Many families experienced challenging socio-economic circumstances. Poor acceptability was mitigated by sympathetic study personnel, assistance with transport and financial compensation. The adult formulation of levofloxacin was disliked by many younger children but was acceptable to children able to swallow the tablet whole. In addition to using acceptable drug formulations, TB preventive treatment implementation models should include patient education and should accommodate patients' socioeconomic challenges.

'We did not even know it was tuberculosis': a qualitative evaluation of integrating tuberculosis services into paediatric entry points in the CaP-TB programme in Cameroon and Kenya

Introduction

Paediatric tuberculosis (TB) is often undiagnosed and under-reported. The Catalysing Paediatric TB (CaP-TB) programme provided integrated and decentralised TB screening and diagnosis services through multiple paediatric care entry points. This qualitative evaluation explores acceptability of the CaP-TB programme and existing knowledge and perceptions of paediatric TB.

Methods

A descriptive qualitative study was conducted in four sites in Kenya and six sites in Cameron. 54 in-depth interviews were conducted with caregivers, community workers (CWs) and CaP-TB programme managers, and 7 focus group discussions with healthcare workers (HCWs) and CWs. Thematic analysis identified emerging recurrent themes across participants' responses. Data were coded by using MAXQDA V.12. Data were collected during March-September 2021.

Results

Caregivers were often not aware that children were at risk for TB. HCWs reported limited knowledge about paediatric TB prior to CaP-TB. Sometimes caregivers refused to have their children tested for paediatric TB, and this was often related to a lack of awareness of paediatric TB and free services, concerns about the testing procedure and treatment and fear of stigma. TB was referred to as disease of 'shame,' associated with poverty and poor hygiene. The CaP-TB programme increased HCWs knowledge about symptoms of paediatric TB and motivation to investigate children with clinical presentations consistent with possible TB. Adding screening at all entry points was perceived to be beneficial to caregivers who would not have felt comfortable bringing their child to a TB unit. HCWs also discussed the increased workload with CaP-TB, challenges with medication stock-outs and a need for additional training.

Conclusions

CaP-TB illustrated the positive impact of decentralised paediatric TB services, including addressing the awareness and knowledge gap among caregivers and HCWs. Multiple entry points increased opportunities for identification of paediatric TB and increased caregiver comfortability with their child being tested for TB.

Trial registration number

NCT03862261.

Trends and risk factors for drug-resistant tuberculosis among children in Sichuan, China: A 10-year retrospective analysis, 2013-2022

To investigate the status of the drug-resistant tuberculosis (DR-TB) among children in Sichuan, and to find out the risk factors and high-risk population related to drug resistance among children. The clinical data of tuberculosis patients ≤14 years old with culture-confirmed tuberculosis hospitalized in Chengdu Public Health Clinical Center from January 2013 through December 2022 were collected. Clinical data such as gender, age, ethnicity, history of anti-TB treatment, history of exposure to tuberculosis, nutritional status, and specific drug resistance of the children were collected and recorded. The drug resistance of children in different age groups (0-4 years old, 5-9 years old, 10-14 years old) and different periods (2013-2017 and 2018-2022) were grouped and compared. Logistic regression analysis was to analyze analysis of risk factors of drug resistance in children. A total of 438 children with culture-confirmed tuberculosis were screened. Among them, 26.19% (11/42) were 0 to 4 years old, 33.33% (22/66) were 5 to 9 years old, and 36.67% (121/330) were 10 to 14 years old among the resistant children. There was no statistically significant difference in the resistance rate among the 3 groups (P = .385). The proportions of DR-TB, monoresistant tuberculosis, polydrug-resistant tuberculosis were decreased during 2019 to 2022 compared with 2013 to 2017 (P < .0001). The resistance rates of drug resistant, monoresistant, polydrug-resistant, isoniazid-resistant, and rifampicin resistant during 2018 to 2022 were decreased compared with those from 2013 to 2017 (P < .05), but the multi-drug resistance rate was not decreased (P = .131, without statistical difference). The results of logistic regression analysis showed that male gender OR = 1.566 (95% CI 1.035-2.369), a history of antituberculosis therapy OR = 4.049 (95% CI 1.442-11.367), and pulmonary and extrapulmonary tuberculosis OR = 7.335 (95% CI 1.401-38.392) were risk factors for the development of drug resistance; but fever OR = 0.581 (95% CI 0.355-0.950) was Protective factor. The total drug resistance rate of children in Sichuan showed a downward trend, but the rate of multi-drug-resistant tuberculosis was still at a high level, and the form of drug resistance was still severe. Absence of fever, male, retreatment, and pulmonary concurrent with extrapulmonary tuberculosis are risk factors for DR-TB in children.

Acceptability of levofloxacin dispersible and non-dispersible tablet formulations in children receiving TB preventive treatment

BACKGROUND

We evaluated the palatability and acceptability of a 100 mg dispersible and a non-dispersible 250 mg levofloxacin (LVX) tablet formulation in children.

METHODS

Perform was a randomised, open-label, cross-over trial of the relative bioavailability of LVX dispersible vs. crushed non-dispersible tablets in children aged <6 years routinely receiving TB preventive treatment. Children and caregivers completed Likert- and ranking-type measures on the acceptability of both formulations. We used summary, comparative and ranking statistics to characterise formulation acceptability.

RESULTS

A total of 25 children were enrolled (median age: 2.6 years, IQR 1.6-4.0). Caregivers reported frequent challenges with preventive therapy in routine care prior to study entry, including taste of tablets (n = 14, 56%), vomiting/spitting out medicines (n = 11, 44%), and children refusing medicines (n = 10, 40%). Caregivers reported that the dispersible formulation was easier for their child to take than the non-dispersible formulation (P = 0.0253). Mean ranks for caregiver's formulation preferences (dispersible tablets: 1.48, SD ±0.71; non-dispersible tablets: 2.12, SD ±0.67; routinely available formulations: 2.40 SD ±0.82) differed significantly (Friedman's F 11.120; P < 0.0038); post-hoc testing showed dispersible tablets were preferred over non-dispersible (P = 0.018) and routinely available LVX formulations (P < 0.001).

CONCLUSIONS

The dispersible LVX 100 mg tablet formulation was preferred and should be prioritised for integration into routine care.

Optimizing the design of a pharmacokinetic trial to evaluate the dosing scheme of a novel tuberculosis drug in children living with or without HIV

Pharmacokinetic (PK) studies in children are usually small and have ethical constraints due to the medical complexities of drawing blood in this special population. Often, population PK models for the drug(s) of interest are available in adults, and these models can be extended to incorporate the expected deviations seen in children. As a consequence, there is increasing interest in the use of optimal design methodology to design PK sampling schemes in children that maximize information using a small sample size and limited number of sampling times per dosing period. As a case study, we use the novel tuberculosis drug delamanid, and show how applications of optimal design methodology can result in highly efficient and model-robust designs in children for estimating PK parameters using a limited number of sampling measurements. Using developed population PK models based on available data from adults living with and without HIV, and limited data on children without HIV, competing designs for children living with HIV were derived and assessed based on robustness to model uncertainty.

Solans B, Hesseling AC, Winckler J, Schaaf HS, Draper HR, van der Laan L, Hughes J, Fourie B, Nielsen J, Wiesner L, Garcia-Prats AJ, Savic RM. Pharmacokinetics and cardiac safety of clofazimine in children with rifampicin-resistant tuberculosis

Clofazimine is recommended for the treatment of rifampicin-resistant tuberculosis (RR-TB), but there is currently no verified dosing guideline for its use in children. There is only limited safety and no pharmacokinetic (PK) data available for children. We aimed to characterize clofazimine PK and its relationship with QT-interval prolongation in children. An observational cohort study of South African children <18 years old routinely treated for RR-TB with a clofazimine-containing regimen was analyzed. Clofazimine 100 mg gelatin capsules were given orally once daily (≥20 kg body weight), every second day (10 to <20 kg), or thrice weekly (<10 kg). PK sampling and electrocardiograms were completed pre-dose and at 1, 4, and 10 hours post-dose, and the population PK and Fridericia-corrected QT (QTcF) interval prolongation were characterized. Fifty-four children contributed both PK and QTcF data, with a median age (2.5th-97.5th centiles) of 3.3 (0.5-15.6) years; five children were living with HIV. Weekly area under the time-concentration curve at steady state was 79.1 (15.0-271) mg.h/L compared to an adult target of 60.9 (56.0-66.6) mg.h/L. Children living with HIV had four times higher clearance compared to those without. No child had a QTcF ≥500 ms. A linear concentration-QTcF relationship was found, with a drug effect of 0.05 (0.027, 0.075) ms/µg/L. In some of the first PK data in children, we found clofazimine exposure using an off-label dosing strategy was higher in children versus adults. Clofazimine concentrations were associated with an increase in QTcF, but severe prolongation was not observed. More data are required to inform dosing strategies in children.

Interventional bronchoscopy in pediatric pulmonary tuberculosis

INTRODUCTION

Lymphobronchial tuberculosis (TB) is common in children with primary TB and enlarged lymph nodes can cause airway compression of the large airways. If not treated correctly, airway compression can result in persistent and permanent parenchymal pathology, as well as irreversible lung destruction. Bronchoscopy was originally used to collect diagnostic samples; however, its role has evolved, and it is now used as an interventional tool in the diagnosis and management of complicated airway disease. Endoscopic treatment guidelines for children with TB are scarce.

AREAS COVERED

The role of interventional bronchoscopy in the diagnosis and management of complicated pulmonary TB will be discussed. This review will provide practical insights into how and when to perform interventional procedures in children with complicated TB for both diagnostic and therapeutic purposes. This discussion incorporates current scientific evidence and refers to adult literature, as some of the interventions have only been done in adults but may have a role in children. Limitations and future perspectives will be examined.

EXPERT OPINION

Pediatric pulmonary TB lends itself to endoscopic interventions as it is a disease with a good outcome if treated correctly. However, interventions must be limited to safeguard the parenchyma and prevent permanent damage.

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.

Analysis of Drug-Resistant Tuberculosis in Children in Shenyang, China, 2017-2021

Objective

Drug-resistant tuberculosis (DR-TB) in children seriously threatens TB control. Information on the epidemiology and characteristics of DR-TB in children in China is limited. We studied data in Shenyang Tenth People's Hospital to understand the DR-TB epidemiology in children in Shenyang.

Design or Methods

We retrospectively analyzed drug resistance testing data of pediatric TB patients between 2017 and 2021, and included 2976 clinically-diagnosed pediatric TB patients. We described the epidemiology of DR-TB and analyzed the trends of DR-TB incidence. The Kappa value was calculated to assess the agreement between MGIT 960 DST and Xpert MTB/RIF for detecting rifampicin resistance. Multivariate logistic regression was used to identify the risk factors for DR-TB in pediatric patients.

Results

Of the 2976 TB patients, 1076 were confirmed by MGIT 960 culture and/or Xpert MTB/RIF. Among the 806 patients identified by MGIT 960 culture, 232 cases (28.78%) were DR-TB. Resistance to the six drugs was in the following order: streptomycin (21.09%), isoniazid (9.35%), rifampin (15.01%), levofloxacin (6.20%), ethambutol (4.22%), and amikacin (3.23%). Alarmingly, 12.90% were MDR-TB (104/806), including 28 (3.47%) pre-XDR-TB. Of the 1076 pediatric TB patients, 295 (27.4%) developed DR-TB to any one drug (including 69 rifampicin-resistant cases identified by Xpert MTB/RIF only). No difference was found in the incidence of pediatric DR-TB between 2017 and 2021. Among 376 patients who were positive for both methods, using the MGIT 960 DST results as the gold standard, Xpert MTB/RIF's sensitivity for detecting rifampicin resistance was 91.38% and its specificity was 94.65%.

Conclusion

Between 2017 and 2021, the DR-TB incidence in children remained unchanged in Shenyang. RR-TB, MDR-TB, and even Pre-XDR-TB require attention in children with drug-resistant TB. Xpert MTB/RIF helped to detect more rifampicin-resistant pediatric patients; thus Xpert MTB/RIF should be widely used as an important complementary tool to detect rifampicin-resistant TB in children.

Evaluation of 2,3-dihydroimidazo[2,1-b]oxazole and imidazo[2,1-b]oxazole derivatives as chemotherapeutic agents

Imidazo[2,1-b]oxazole and 2,3-dihydroimidazo[2,1-b]oxazole ring systems are commonly employed in therapeutically active molecules. In this article, the authors review the utilization of these core scaffolds as chemotherapeutic agents from 2018 to 2022. These scaffolds possess many important biological activities including antimicrobial and anticancer, among others. This review covers their biological activities and structure-activity relationships. One of the most important drugs in this class of compounds is the antitubercular agent delamanid. In this paper, the compounds structure-activity relationship and preclinical and clinical trial data are thoroughly presented.

Bedaquiline (BDQ) resistance in an adolescent with multidrug-resistant tuberculosis (MDR-TB): An alarm for pediatricians

Bedaquiline (BDQ) use for all age groups in drug-resistant (DR) tuberculosis (TB) regimens for children may be shorter, safer, and more effective. However, the emergence of BDQ resistance reports soon after its introduction is alarming. We report the case of a 17-year-old boy, initially diagnosed with Rifampicin-resistant (RR)-TB and developed BDQ resistance during the treatment. To the best of our knowledge, this is the first report of BDQ resistance in pediatric.

Advances of new drugs bedaquiline and delamanid in the treatment of multi-drug resistant tuberculosis in children

Tuberculosis (TB) is a major public health problem, with nearly 10 million new cases and millions of deaths each year. Around 10% of these cases are in children, but only a fraction receive proper diagnosis and treatment. The spread of drug-resistant (DR) strain of TB has made it difficult to control, with only 60% of patients responding to treatment. Multi-drug resistant TB (MDR-TB) is often undiagnosed in children due to lack of awareness or under-diagnosis, and the target for children's DR-TB treatment has only been met in 15% of goals. New medications such as bedaquiline and delamanid have been approved for treating DR-TB. However, due to age and weight differences, adults and children require different dosages. The availability of child-friendly formulations is limited by a lack of clinical data in children. This paper reviews the development history of these drugs, their mechanism of action, efficacy, safety potential problems and current use in treating DR-TB in children.

Trends and challenges of multi-drug resistance in childhood tuberculosis

Drug-resistant tuberculosis (DR-TB) in children is a growing global health concern, This review provides an overview of the current epidemiology of childhood TB and DR-TB, including prevalence, incidence, and mortality. We discuss the challenges in diagnosing TB and DR-TB in children and the limitations of current diagnostic tools. We summarize the challenges associated with treating multi-drug resistance TB in childhood, including limitations of current treatment options, drug adverse effects, prolonged regimens, and managing and monitoring during treatment. We highlight the urgent need for improved diagnosis and treatment of DR-TB in children. The treatment of children with multidrug-resistant tuberculosis will be expanded to include the evaluation of new drugs or new combinations of drugs. Basic research is needed to support the technological development of biomarkers to assess the phase of therapy, as well as the urgent need for improved diagnostic and treatment options.

Tuberculosis Diagnosis and Preventive Monotherapy Among Children and Adolescents Exposed to Rifampicin-Resistant Tuberculosis in the Household

Background

Children and adolescents with household exposure to multidrug- or rifampicin-resistant tuberculosis (MDR/RR-TB) are at high risk of developing TB disease. Tuberculosis preventive therapy (TPT) is recommended, but programmatic experience is limited, particularly for adolescents.

Methods

We conducted a prospective cohort study to describe MDR/RR-TB diagnosis and TPT provision for individuals aged <18 years with MDR/RR-TB exposure. Participants were assessed for TB either in homes or health facilities, with referral for chest x-ray or specimen collection at clinician discretion. The TPT regimens included levofloxacin, isoniazid, or delamanid monotherapy for 6 months, based on source patient drug-resistance profile.

Results

Between March 1, 2020 and July 31, 2021, 112 participants were enrolled; median age was 8.5 years, 57 (51%) were female, and 6 (5%) had human immunodeficiency virus. On screening, 11 (10%) were diagnosed with TB: 10 presumptive MDR/RR-TB and 1 drug-susceptible TB. Overall, 95 (94% of 101) participants started TPT: 79 with levofloxacin, 9 with isoniazid, and 7 with delamanid. Seventy-six (80%) completed TPT, 12 (13%) were lost to follow up, and 7 (7%) stopped TPT early due to adverse events. Potential adverse events were reported for 12 (13%) participants; none were serious. There were no further TB diagnoses (200 days median follow up).

Conclusions

Post-MDR/RR-TB exposure management for children and adolescents resulted in significant MDR/RR-TB detection and both high TPT initiation and completion. Tuberculosis preventive monotherapy was well tolerated and there were no further TB diagnoses after initial assessment. Key factors supporting these outcomes included use of pediatric formulations for young children, monotherapy, and community-based options for assessment and follow up.

Complicated intrathoracic tuberculosis: Role of therapeutic interventional bronchoscopy

In recent years bronchoscopy equipment has been improved with smaller instruments and larger size working channels. This has ensured that bronchoscopy offers both therapeutic and interventional options. As the experience of paediatric interventional pulmonologists continues to grow, more interventions are being performed. There is a scarcity of published evidence in the field of interventional bronchoscopy in paediatrics. This is even more relevant for complicated pulmonary tuberculosis (PTB). Therapeutic interventional bronchoscopy procedures can be used in the management of complicated tuberculosis, including for endoscopic enucleations, closure of fistulas, dilatations of bronchial stenosis and severe haemoptysis. Endoscopic therapeutic procedures in children with complicated TB may prevent thoracotomy. If done carefully these interventional procedures have a low complication rate.

Multidrug-Resistant TB (MDR-TB) and Extensively Drug-Resistant TB (XDR-TB) Among Children: Where We Stand Now

Drug-resistant tuberculosis (DR-TB) has continued to be a global health cataclysm. It is an arduous condition to tackle but is curable with the proper choice of drug and adherence to the drug therapy. WHO has introduced newer drugs with all-oral shorter regimens, but the COVID-19 pandemic has disrupted the achievements and raised the severity. The COVID-19 controlling mechanism is based on social distancing, using face masks, personal protective equipment, medical glove, head shoe cover, face shield, goggles, hand hygiene, and many more. Around the globe, national and international health authorities impose lockdown and movement control orders to ensure social distancing and prevent transmission of COVID-19 infection. Therefore, WHO proposed a TB control program impaired during a pandemic. Children, the most vulnerable group, suffer more from the drug-resistant form and act as the storehouse of future fatal cases. It has dire effects on physical health and hampers their mental health and academic career. Treatment of drug-resistant cases has more success stories in children than adults, but enrollment for treatment has been persistently low in this age group. Despite that, drug-resistant childhood tuberculosis has been neglected, and proper surveillance has not yet been achieved. Insufficient reporting, lack of appropriate screening tools for children, less accessibility to the treatment facility, inadequate awareness, and reduced funding for TB have worsened the situation. All these have resulted in jeopardizing our dream to terminate this deadly condition. So, it is high time to focus on this issue to achieve our Sustainable Development Goals (SDGs), the goal of ending TB by 2030, as planned by WHO. This review explores childhood TB's current position and areas to improve. This review utilized electronic-based data searched through PubMed, Google Scholar, Google Search Engine, Science Direct, and Embase.

Treatment options for children with multi-drug resistant tuberculosis

INTRODUCTION

According to the latest report from the World Health Organization (WHO), approximately 10.0 million people fell ill with tuberculosis (TB) in 2020, 12% of which were children aged under 15 years. There is very few experience on treatment of multi-drug resistant (MDR)-TB in pediatrics.

AREAS COVERED

The aim of this review is to analyze and summarize therapeutic options available for children experiencing MDR-TB. We also focused on management of MDR-TB prophylaxis.

EXPERT OPINION

The therapeutic management of children with MDR-TB or MDR-TB contacts is complicated by a lack of knowledge, and the fact that many potentially useful drugs are not registered for pediatric use and there are no formulations suitable for children in the first years of life. Furthermore, most of the available drugs are burdened by major adverse events that need to be taken into account, particularly in the case of prolonged therapy. A close follow-up with a standardized timeline and a comprehensive assessment of clinical, laboratory, microbiologic and radiologic data is extremely important in these patients. Due to the complexity of their management, pediatric patients with confirmed or suspected MDR-TB should always be referred to a specialized center.

Hepatocellular Injury in Children Treated for Rifampicin-resistant Tuberculosis: Incidence, Etiology and Outcome

BACKGROUND

Hepatocellular injury has been reported commonly in adults on rifampicin-resistant and multidrug-resistant tuberculosis (RR/MDR-TB) treatment. However, there are limited data in children.

METHODS

Two pharmacokinetic studies of children (0-17 years) routinely treated for RR/MDR-TB were conducted in Cape Town, South Africa between October 2011 and February 2020. Hepatocellular injury adverse events (AEs; defined as elevated alanine aminotransferase [ALT]) were documented serially. Data were analyzed to determine the incidence, etiology, risk factors, management and outcome of ALT elevation.

RESULTS

A total of 217 children, median age 3.6 years (interquartile range, 1.7-7.1 years) at enrollment were included. The median follow-up time was 14.0 months (interquartile range, 9.8-17.2 months). Fifty-five (25.3%) patients developed an ALT AE. Of these, 43 of 55 (78%) patients had 54 ALT AEs attributed to their RR/MDR-TB treatment. The incidence rate of ALT AEs related to RR-TB treatment was 22.4 per 100 person-years. Positive HIV status and having an elevated ALT at enrollment were associated with time to ALT AE attributed to RR/MDR-TB treatment, with P values 0.0427 and P < 0.0001, respectively. Hepatitis A IgM was positive in 11 of 14 (78.6%) severe (grade ≥3) cases of ALT AEs. In 8 of 14 (57%) severe ALT AEs, hepatotoxic drugs were stopped or temporarily interrupted. None had a fatal or unresolved outcome.

CONCLUSIONS

Hepatocellular injury in children on RR/MDR-TB treatment is common, although usually mild; having elevated ALT early in treatment and HIV-positive status are possible risk factors. Hepatitis A was a common etiology of severe ALT AE in children treated for RR/MDR-TB.

Pharmacokinetics and Safety of Bedaquiline in Human Immunodeficiency Virus (HIV)-Positive and Negative Older Children and Adolescents With Rifampicin-Resistant Tuberculosis

BACKGROUND

Pharmacokinetic data for bedaquiline in children are limited. We described the pharmacokinetics and safety of bedaquiline in South African children and adolescents receiving treatment for multidrug/rifampicin-resistant tuberculosis (MDR/RR-TB) in routine care.

METHODS

In this observational cohort study, children aged 6-17 years receiving bedaquiline at recommended doses as part of MDR/RR-TB treatment underwent semi-intensive pharmacokinetic sampling. Bedaquiline and the M2 metabolite plasma concentrations were quantified, and nonlinear mixed-effects modeling performed. Pediatric data were described using a pre-established model of bedaquiline pharmacokinetics in adults. The exposure reference was 187 µg ⋅ h/mL, the median weekly area under the curve (AUC) of adults at week 24 of treatment with bedaquiline. Safety was assessed through monthly clinical, blood and electrocardiogram monitoring, and treatment outcomes described.

RESULTS

Fifteen children (3 human immunodeficiency virus [HIV]-positive) with median age 13.3 years (range 6.5-16.3) were included. A bedaquiline pharmacokinetic model was adapted to be allometrically scaled in clearance and volume, centered in the median child population weight. Bedaquiline bioavailability was 57% of that in adults. Overall bedaquiline exposures were below target, and AUC reference attainment was achieved in only 3 (20%) children. Ten children experienced 27 adverse events at least possibly related to bedaquiline; no adverse events led to bedaquiline withdrawal. Two adverse events (arthritis and arthralgia) were considered severe, and 2 children had mild QT interval corrected for heart rate using Fridericia's formula (QT) prolongation.

CONCLUSIONS

The evaluated doses of bedaquiline in children ≥ 6 years of age were safe but achieved slightly lower plasma concentrations compared to adults receiving the recommended dose, possibly due to delayed food intake relative to bedaquiline administration.

The incidence of TB and MDR-TB in pediatrics and therapeutic options: a systematic review

BACKGROUND

Tuberculosis (TB) is considered one of the top 10 causes of death worldwide and the leading cause of death from a single infectious agent. Multidrug-resistant (MDR) TB can affect people of all age groups, including children (aged 0-15 years). However, very little is known about the extent of this problem in children. This systematic review aims to investigate the incidence of TB and drug-resistant (DR) TB among the pediatric population. It also reviews the therapeutic options available to treat the condition.

METHODS

A comprehensive search for all relevant evidence was conducted. The following databases were searched: MEDLINE, CINAHL, and Web of Science. The searched time frame was limited from January 1990 to December 2020 with a focus on the incidence of TB and MDR-TB among pediatrics and the therapeutic options available.

RESULTS

A total of 537 articles were obtained via the selected databases. After title and abstract screening, 418 articles were excluded leaving 119 articles. Full-text screening was conducted on 119 articles, excluding a further 110 articles. Thus, 9 articles were subject to quality assessment and included in this review. The 9 articles represented the age group of 0-15 years and included both males and females. All studies included were of retrospective study design.

DISCUSSION

The included studies mentioned a moderate increase in TB cases among pediatrics exacerbated by malnutrition, lack of bacille Calmette-Guérin (BCG) vaccination, and human immunodeficiency virus (HIV) coinfection. MDR-TB prevalence was especially high in South Africa. Drug therapy for both TB and MDR-TB yielded favorable outcomes among pediatrics. However, one of the biggest challenges with drug therapy includes the dosage forms available.

SYSTEMATIC REVIEW REGISTRATION

DOI: 10.17605/OSF.IO/G34NF.

Delamanid Added to an Optimized Background Regimen in Children with Multidrug-Resistant Tuberculosis: Results of a Phase I/II Clinical Trial

Delamanid has been demonstrated to be safe and effective for treatment of adult multidrug-resistant tuberculosis (MDR-TB) and has been approved by the European Commission for treatment of pediatric MDR-TB patients at least 10 kg in weight, making the drug no longer limited to adults. A 10-day phase I age deescalation study was conducted, followed by a 6-month phase II extension study, to assess the pharmacokinetics, safety, tolerability, and preliminary efficacy of delamanid when combined with optimized background regimen (OBR) in children (birth to 17 years) with MDR-TB. Delamanid administered at 100 mg twice-daily (BID), 50 mg BID, and 25 mg BID resulted in exposures in 12- to 17- (n = 7), 6- to 11- (n = 6), and 3- to 5-year-olds (n = 12), respectively, comparable with those in adults at the approved adult dosage (100 mg BID). Exposures in 0- to 2-year-olds (n = 12) following a weight-based dosing regimen (5 mg once daily [QD] to 10 mg BID) were lower than predicted from pharmacokinetic modeling of the older three age groups and below target exposures in adults. Overall, the safety profile of delamanid in children 0 to 17 years of age was similar to the adult profile. At 24 months after the first delamanid dose, 33/37 children (89.2%) had favorable treatment outcomes, as defined by the World Health Organization (15/37 [40.5%] cured and 18/37 [48.6%] completed treatment). A new pediatric delamanid formulation used in 0- to 2-year-olds and 3- to 5-year-olds was palatable per child/parent and nurse/investigator reports. Data from initial phase I/II studies inform our understanding of delamanid use in children and support its further assessment in the setting of pediatric MDR-TB. (This study has been registered at ClinicalTrials.gov under identifiers NCT01856634 [phase I trial] and NCT01859923 [phase II trial].).

Tuberculosis in Children in a Pediatric Hospital in Mexico

Tuberculosis (TB) remains a global problem and a diagnostic challenge, especially in pediatrics. The aim of this study was to describe the clinical, microbiological, radiological, and histopathological data of TB in children. A 7-year retrospective and descriptive cohort study that included 127 patients under 18 years of age with diagnosis of active TB was conducted from 2011 to 2018 in a pediatric hospital. Tuberculosis was microbiologically confirmed using Ziehl-Neelsen (ZN) staining, culture or polymerase chain reaction (PCR) in a total of 94 (74%) cases. Thirty-three cases were defined as probable TB based on tuberculin skin test result and epidemiological evaluation. The TB forms found were lymph node (39.3%), bone (15.7%), lung (13.6%), and meningeal TB (8.6%). The most common symptoms were fever (48.8%) and adenopathy (45.6%). History of contact was established in 34.6%. Positive ZN staining (sensitivity 30%) and culture (sensitivity 37%) were found in 29% and 37.7% of subjects, respectively. About 64.5% depicted abnormal chest X-ray. Xpert MTB/RIF® (PCR) was positive in 9.4% and biopsy was compatible in 52.7% of these samples. It is fundamental to have laboratory and epidemiological evaluation that support the diagnosis of the disease in children and thus, define its management; since, in most cases, early microbiologic confirmation is lacking.

Characterizing Absorption Properties of Dispersible Pretomanid Tablets Using Population Pharmacokinetic Modelling

BACKGROUND AND INTRODUCTION

The dispersible tablet formulation (DTF) of pretomanid has been developed to facilitate future use in children. This work aimed to assess the pharmacokinetics (PK) and relative bioavailability of the DTF compared to the marketed formulation (MF) and the potential influence of dose.

METHODS

Pretomanid DTF was investigated in a single-dose, randomized, four-period, cross-over study, with 7 days of washout between doses. Forty-eight healthy volunteers were enrolled and randomized into one of two panels to receive doses either in the fasted state or after a high-fat meal. Each volunteer received doses of 10, 50, and 200 mg DTF, and 200 mg MF pretomanid. Blood samples for pharmacokinetic assessment were drawn following a rich schedule up to 96 h after each single dose. The study data from the panel receiving the high-fat meal were analyzed using a nonlinear mixed-effects modeling approach, and all data were characterized with noncompartmental methods.

RESULTS

A one-compartment model with first-order elimination and absorption through a transit compartment captured the mean and variability of the observed pretomanid concentrations with acceptable precision. No significant difference in bioavailability was found between formulations. The mean absorption time for the DTF was typically 137% (86-171%) of that for the MF. The bioavailability was found to be dose dependent with a small positive and larger negative correlation under fed and fasted conditions, respectively.

CONCLUSION

Using data from a relative bioavailability study in healthy adult volunteers, a mathematical model has been developed to inform dose selection for the investigation of pretomanid in children using the new dispersible tablet formulation. Under fed conditions and at the currently marketed adult dose of 200 mg, the formulation type was found to influence the absorption rate, but not the bioavailability. The bioavailability of the DTF was slightly positively correlated with doses when administered with food.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04309656, first posted on 16 March 2020.

High rate of successful treatment outcomes among childhood rifampicin/multidrug-resistant tuberculosis in Pakistan: a multicentre retrospective observational analysis

Background

There was a complete lack of information about the treatment outcomes of rifampicin/multidrug resistant (RR/MDR) childhood TB patients (age ≤ 14 years) from Pakistan, an MDR-TB 5th high burden country. Therefore, this study evaluated the socio-demographic characteristics, drug resistance pattern, treatment outcomes and factors associated with unsuccessful outcomes among childhood RR/MDR-TB patients in Pakistan.

Methods

This was a multicentre retrospective record review of all microbiologically confirmed childhood RR/MDR-TB patients (age ≤ 14 years) enrolled for treatment at seven units of programmatic management of drug-resistant TB (PMDT) in Pakistan. The baseline and follow-up information of enrolled participants from treatment initiation until the end of treatment were retrieved from electronic nominal recording and reporting system. World Health Organization (WHO) defined criterion was used for deciding treatment outcomes. The outcomes of “cured” and “treatment completed” were collectively grouped as successful, whereas “death”, “treatment failure” and “lost to follow-up” were grouped together as unsuccessful outcomes. Multivariable binary logistic regression analysis was used to find factors associated with unsuccessful outcomes. A p-value < 0.05 reflected statistically significant findings.

Results

A total of 213 children RR/MDR-TB (84 RR and 129 MDR-TB) were included in the study. Majority of them were females (74%), belonged to the age group 10–14 years (82.2%) and suffered from pulmonary TB (85.9%). A notable proportion (37.1%) of patients had no history of previous TB treatment. Patients were resistant to a median of two drugs (interquartile range: 1–4) and 23% were resistant to any second line anti-TB drug. A total of 174 (81.7%) patients achieved successful treatment outcomes with 144 (67.6%) patients being cured and 30 (14.1%) declared treatment completed. Among the 39 (18.3%) patients with unsuccessful outcomes, 35 (16.4%) died and 4 (1.9%) experienced treatment failure. In multivariable analysis, the use of ethambutol had statistically significant negative association with unsuccessful outcomes (odds ratio = 0.36, p-value = 0.02).

Conclusions

In this study, the WHO target of successful treatment outcomes (≥ 75%) among childhood RR/MDR-TB patients was achieved. The notable proportion of patients with no history of previous TB treatment (37.1%) and the disproportionately high number of female patients (74%) respectively stress for infection control measures and provision of early and high quality care for female drug susceptible TB patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06935-6.

Drug resistance pattern and mutation pattern in pediatric tuberculosis: Study from north India

BACKGROUND

The emergence of multidrug-resistant MDR-TB and extensively drug-resistant XDR-TB are serious threats to global TB control. Molecular tests like GenoType MTBDRplus has revolutionized MDR-TB diagnosis by rapid detection of resistance, leading to early and appropriate management of DR-TB. Information about common mutations imparting resistance to RIF and INH, helps in understanding the disease epidemiology in various regions. The study was conducted to determine the genetic mutation in drug resistant tuberculosis in children less than 12 years with pulmonary or extrapulmonary tuberculosis.

MATERIALS/METHODS

Retrospective analysis was done over a period of 54 months from January 2015 to June 2019 to study the resistance pattern and mutations present in DR-TB in children less than 12 years with suspected pulmonary or extrapulmonary tuberculosis using Hain's GenoType MTBDRplus VER 2.0.

RESULTS

Over a period of 54 months, samples from 3461 patients with suspected TB were received for MGIT culture, out of which, 347 were positive for Mycobacterium tuberculosis. 250 of these 347 isolated were tested for drug resistance by Hain's GenoType MTBDRplus VER 2.0.61.1% were sensitive to isoniazid and rifampicin while 15.2% were DR-TB (38 out of 250). Out of these 38, 22 were MDR TB, 13 were isoniazid monoresistant (34.2%) and 3 were rifampicin monoresistant. The most common genotypic resistance for rifampicin was absence of rpoB WT8 band and presence of rpoB MUT 3 band (88%). 84.6% of the INH monoresistant isolates showed high level isoniazid resistant. All these isolates showed presence of katG MUT 1 band. On comparing Hain's GenoType MTBDRplus VER 2.0 with Xpert MTB/Rif Assay, most common mutation for rifampicin resistance at S531L which can be detected by Xpert MTB/Rif Assay (probe E). However, two cases with rifampicin resistance had mutation in codon region 509-513 and 513-519 which could be missed by Xpert MTB/Rif Assay.

CONCLUSIONS

We cannot solely rely on Xpert MTB/Rif Assay for detection of drug resistance due to the risk of missing the isoniazid monoresistance. GenoType MTBDRplus has revolutionized MDR-TB diagnosis by substantially reducing turn around time and leading to early management of DR-TB cases.

Analysis of Factors Influencing Multidrug-Resistant Tuberculosis and Validation of Whole-Genome Sequencing in Children with Drug-Resistant Tuberculosis

Objective

Pediatric tuberculosis (TB) is one of the top ten causes of death in children. Our study was to analyze influencing factors of multidrug-resistant tuberculosis (MDR-TB) and validation of whole-genome sequencing (WGS) used in children with drug-resistant TB (DR-TB).

Methods

All Mycobacterium tuberculosis (Mtb) strains were isolated from patients aged below 18 years old of Children’s Hospital of Chongqing Medical University, China. A total of 208 Mtb isolates were tested for eight anti-TB drugs with phenotypic drug susceptibility test (DST) and for genetic prediction of the susceptible profile with WGS. The patients corresponding to each strain were grouped according to drug resistance and genotype. Influencing factors of MDR-TB and DR-TB were analyzed.

Results

According to the phenotypic DST and WGS, 82.2% of Mtb strains were susceptible to all eight drugs, and 6.3% were MDR-TB. Using the phenotypic DSTs as the gold standard, the kappa value of WGS to predict isoniazid, rifampin, ethambutol, rifapentine, prothionamide, levofloxacin, moxifloxacin and amikacin was 0.84, 0.89, 0.59, 0.86, 0.89, 0.82, 0.88 and 1.00, respectively. There was significant difference in the distribution of severe TB, diagnosis, treatment and outcome between MDR and drug-susceptible group (P<0.05). The distribution of severe TB and treatment between DR and drug-susceptible group was statistically different (P<0.05). The results of binary logistic regression showed that Calmette–Guérin bacillus (BCG) vaccine is the protective factor for MDR-TB (OR=0.19), and MDR-TB is the risk factor for PTB and EPTB (OR=17.98).

Conclusion

The BCG vaccine is a protective factor for MDR-TB, and MDR-TB might not be confined to pulmonary infection, spreading to extrapulmonary organs in children. MDR-TB had more severe cases and a lower recovery rate than drug-susceptible TB. WGS could provide an accurate prediction of drug susceptibility test results for anti-TB drugs, which are needed for the diagnosis and precise treatment of TB in children.

Pharmacokinetics and Drug-Drug Interactions of Abacavir and Lamuvudine Co-administered With Antituberculosis Drugs in HIV-Positive Children Treated for Multidrug-Resistant Tuberculosis

Given the high prevalence of multidrug-resistant (MDR)-TB in high HIV burden settings, it is important to identify potential drug-drug interactions between MDR-TB treatment and widely used nucleoside reverse transcriptase inhibitors (NRTIs) in HIV-positive children. Population pharmacokinetic models were developed for lamivudine (n = 54) and abacavir (n = 50) in 54 HIV-positive children established on NRTIs; 27 with MDR-TB (combinations of high-dose isoniazid, pyrazinamide, ethambutol, ethionamide, terizidone, fluoroquinolones, and amikacin), and 27 controls without TB. Two-compartment models with first-order elimination and transit compartment absorption described both lamivudine and abacavir pharmacokinetics, respectively. Allometric scaling with body weight adjusted for the effect of body size. Clearance was predicted to reach half its mature value ∼ 2 (lamivudine) and ∼ 3 (abacavir) months after birth, with completion of maturation for both drugs at ∼ 2 years. No significant difference was found in key pharmacokinetic parameters of lamivudine and abacavir when co-administered with routine drugs used for MDR-TB in HIV-positive children.

Bedaquiline for multidrug-resistant TB in paediatric patients

BACKGROUND:

TMC207-C211 (NCT02354014) is a Phase 2, open-label, multicentre, single-arm study to evaluate pharmacokinetics, safety/tolerability, antimycobacterial activity and dose selection of bedaquiline (BDQ) in children (birth to <18 years) with multidrug-resistant-TB (MDR-TB).

METHODS:

Patients received 24 weeks’ BDQ with an anti-MDR-TB background regimen (BR), followed by 96 weeks of safety follow-up. Results of the primary analysis are presented based on data up to 24 weeks for Cohort 1 (≥12–<18 years; approved adult tablet at the adult dosage) and Cohort 2 (≥5–<12 years; age-appropriate 20 mg tablet at half the adult dosage).

RESULTS:

Both cohorts had 15 patients, of whom respectively 53% and 40% of Cohort 1 and Cohort 2 children had confirmed/probable pulmonary MDR-TB. Most patients completed 24 weeks’ BDQ/BR treatment (Cohort 1: 93%; Cohort 2: 67%). Geometric mean BDQ area under the curve 168h values of 119,000 ng.h/mL (Cohort 1) and 118,000 ng.h/mL (Cohort 2) at Week 12 were within 60–140% (86,200–201,000 ng.h/mL) of adult target values. Few adverse event (AE) related discontinuations or serious AEs, andnoQTcF >460 ms during BDQ/BR treatment or deaths occurred. Of MGIT-evaluable patients, 6/8 (75%) Cohort 1 and 3/3 (100%) Cohort 2 culture converted.

CONCLUSION:

In children and adolescents aged ≥5–<18 years with MDR-TB, including pre-extensively drug-resistant-TB (pre-XDR-TB) or XDR-TB, 24 weeks of BDQ provided a comparable pharmacokinetic and safety profile to adults.

Treatment of Multidrug-Resistant and Extensively Drug-Resistant Tuberculosis in Children: The Role of Bedaquiline and Delamanid

Multidrug-resistant (MDR) tuberculosis (TB) has been emerging at an alarming rate over the last few years. It has been estimated that about 3% of all pediatric TB is MDR, meaning about 30,000 cases each year. Although most children with MDR-TB can be successfully treated, up to five years ago effective treatment was associated with a high incidence of severe adverse effects and patients with extensively drug-resistant (XDR) TB had limited treatment options and no standard regimen. The main objective of this manuscript is to discuss our present knowledge of the management of MDR- and XDR-TB in children, focusing on the characteristics and available evidence on the use of two promising new drugs: bedaquiline and delamanid. PubMed was used to search for all of the studies published up to November 2020 using key words such as "bedaquiline" and "delamanid" and "children" and "multidrug-resistant tuberculosis" and "extensively drug-resistant tuberculosis". The search was limited to articles published in English and providing evidence-based data. Although data on pediatric population are limited and more studies are needed to confirm the efficacy and safety of bedaquiline and delamanid, their use in children with MDR-TB/XDR-TB appears to have good tolerability and efficacy. However, more evidence on these new anti-TB drugs is needed to better guide their use in children in order to design effective shorter regimens and reduce adverse effects, drug interactions, and therapeutic failure.

Challenging drug-resistant TB treatment journey for children, adolescents and their care-givers: A qualitative study

BACKGROUND

Childhood multidrug-resistant TB (MDR-TB) still affects around 25000 children every year across the globe. Though the treatment success rates for drug-resistant TB (DR-TB) in children are better than adults, children and adolescents face unique hurdles during DR-TB (MDR-TB, Pre-XDR TB and XDR-TB) treatment. This study aimed to understand the patients, guardians and healthcare providers' perspectives about DR-TB treatment journey of patients and caregivers.

METHODS

This is a qualitative study involving in depth-interviews of purposively selected adolescents (n = 6), patients guardians (for children and adolescents, n = 5) and health care providers (n = 8) of Médecins Sans Frontières (MSF) clinic, Mumbai, India. In-depth face to face interviews were conducted in English or Hindi language using interview guides during September-November 2019. The interviews were audio-recorded after consent. Thematic network analysis was used to summarize textual data. ATLAS.ti (version 7) was used for analysis.

RESULT

The age of adolescent patients ranged from 15-19 years and four were female. Five guardians (of three child and two adolescent patients) and eight healthcare providers (including clinicians- 2, DOT providers-2, counselors-2 and programme managers-2) were interviewed. The overarching theme of the analysis was: Challenging DR-TB treatment journey which consisted of four sub-themes: 1) physical-trauma, 2) emotional-trauma, 3) unavailable social-support and 4) non-adapted healthcare services. Difficulties in compounding of drugs were noted for children while adolescents shared experiences around disruption in social life due to disease and treatment. Most of the patients and caregivers experienced treatment fatigue and burnout during the DR-TB treatment. Participants during interviews gave recommendations to improve care.

DISCUSSION

The TB programmes must consider the patient and family as one unit when designing the package of care for paediatric DR-TB. Child and adolescent friendly services (paediatric-formulations, age-specific counselling tools and regular interaction with patients and caregivers) will help minimizing burnout in patients and caregivers.

Ongoing challenges to understanding multidrug- and rifampicin-resistant tuberculosis in children versus adults

Previous analyses suggest that children with tuberculosis (TB) are no more or no less likely to have multidrug (MDR)- or rifampicin-resistant (RR)-TB than adults. However, the availability of new data, particularly for high MDR/RR-TB burden countries, suggest updates of country-specific estimates are warranted.We used data from population-representative surveys and surveillance collected between 2000 and 2018 to compare the odds ratio of MDR/RR-TB among children (aged <15 years) with TB, compared to the odds of MDR/RR-TB among adults (aged ≥15 years) with TB.In most settings (45 out of 55 countries), and globally as a whole, there is no evidence that age is associated with odds of MDR/RR-TB. However, in some settings, such as former Soviet Union countries in general, and Georgia, Kazakhstan, Lithuania, Tajikistan and Uzbekistan in particular, as well as Peru, MDR/RR-TB is positively associated with age ≥15 years. Meanwhile, in Western Europe in general, and the United Kingdom, Poland, Finland and Luxembourg in particular, MDR/RR-TB is positively associated with age <15 years. 16 countries had sufficient data to compare over time between 2000-2011 and 2012-2018, with evidence for decreases in the odds ratio in children compared to adults in Germany, Kazakhstan and the United States of America.Our results support findings that in most settings a child with TB is as likely as an adult with TB to have MDR/RR-TB. However, setting-specific heterogeneity requires further investigation. Furthermore, the odds ratio for MDR/RR-TB in children compared to adults is generally either stable or decreasing. There are important gaps in detection, recording and reporting of drug resistance among paediatric TB cases, limiting our understanding of transmission risks and measures needed to combat the global TB epidemic.