Childhood tuberculosis: an emerging and previously neglected problem

Rapid tuberculosis diagnosis from respiratory or blood samples by a low cost, portable lab-in-tube assay

Rapid portable assays are needed to improve diagnosis, treatment, and reduce transmission of tuberculosis (TB), but current tests are not suitable for patients in resource-limited settings with high TB burden. Here we report a low complexity, lab-in-tube system that is read by an integrated handheld device that detects Mycobacterium tuberculosis (Mtb) DNA in blood and respiratory samples from a variety of clinical settings. This microprocessor-controlled device uses an LCD user interface to control assay performance, automate assay analysis, and provide results in a simple readout. This point-of-care single-tube assay uses a DNA enrichment membrane and a low-cost cellulose disc containing lyophilized recombinase polymerase amplification and CRISPR-Cas12a reagents to attain single-nucleotide specificity and high sensitivity within 1 hour of sample application, without a conventional DNA isolation procedure. Assay results obtained with serum cell-free DNA isolated from a cohort of children aged 1 to 16 years detected pulmonary and extrapulmonary TB with high sensitivity versus culture and GeneXpert MTB/RIF results (81% versus 55% and 68%) and good specificity (94%), meeting the World Health Organization target product profile criteria for new nonsputum TB diagnostics. Changes in assay results for serum isolated during treatment were also highly predictive of clinical response. Results obtained with noninvasive sputum and saliva specimens from adults with bacteriologically confirmed pulmonary TB were also comparable to those reported for reference methods. This rapid and inexpensive lab-in-tube assay approach thus represents one means to address the need for point-of-care TB diagnostics useable in low-resource settings.

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 Xpert MTB/RIF Assay on Stool Samples for the Diagnosis of Pulmonary Tuberculosis among the Pediatric Population

Objective  Microbiological confirmation of tuberculosis (TB) in pediatric cases is challenging due to its paucibacillary nature and difficulty in specimen collection. This study aimed to validate stool as an alternative sample for the diagnosis of pediatric pulmonary TB via Xpert MTB/RIF (Xpert) assay. Materials and Methods  This cross-sectional study included 75 pediatric patients up to 10 years of age with signs and symptoms suggestive of TB. From each recruited patient, pulmonary and stool samples were collected in a sterile container. The collected samples were subjected to Ziehl-Neelsen staining, BACTEC MGIT 960 culture (MGIT), Xpert, and in-house multiplex polymerase chain reaction for TB diagnosis. Results  About 13.33% (10/75) of the pulmonary samples and, of them, 50% (5/75) of the stool samples were positive by Xpert assay. The sensitivity and specificity of Xpert assay with stool and pulmonary samples were 50 (95% confidence interval [CI]: 18.71-81.29%) and 100% (95% CI: 94.48-100%), respectively. Conclusion  The Xpert assay on stool samples showed limited sensitivity and good specificity in the diagnosis of pulmonary TB. Therefore, it can be proposed as an alternative screening sample to diagnose TB in pediatric cases for which getting a respiratory sample is extremely difficult. However, further studies with greater number of samples and multiple baseline variables are required to support our findings. Strategies to optimize stool Xpert assay should be performed to enhance the sensitivity of this method to detect Mycobacterium tuberculosis in children.

Toward a conceptual framework of the acceptability of tuberculosis treatment in children using a theory generative approach

To describe an early-stage holistic framework towards evaluating factors that impact the overall acceptability of TB treatment along the TB care cascade in children. We developed a conceptual framework utilising a theory generative approach. Domains were developed through review of existing definitions and analysis of existing qualitative data undertaken in acceptability studies of TB treatment in children. Clarity of domain definitions was achieved through iterative refinement among the research team. Three domains, each comprising several dimensions, were identified to holistically evaluate treatment acceptability: (1) usability, which involves the alignment between the requirements of treatment use and caregivers' and children's ability to integrate TB treatment into their everyday routines, (2) receptivity, which describes the end-user's perception and expectations of treatment and its actual use, and (3) integration, which describes the relationship between available health services and caregivers/children's capacity to make use of those services. Our framework addresses the gaps in current research which do not account for the influence of caregivers' and children's contexts on TB treatment uptake and overall acceptability. This approach may support the development of more standard, holistic measures to improve TB treatment delivery and experiences and future research in children.

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.

Lipobiotin-capture magnetic bead assay for isolation, enrichment and detection of Mycobacterium tuberculosis from saliva

Background

Pulmonary Tuberculosis (TB) is diagnosed through sputum samples. As sputum sampling is challenging in children and cachexic patients, the development of diagnostic tests using saliva appears promising but has been discouraged due to low bacterial load and poor sensitivity. Here, we present a novel and rapid method to enrich Mycobacterium tuberculosis (Mtb) from saliva, which may serve as a basis for a diagnostic saliva test.

Methods

Lipobiotin-functionalized magnetic beads (LMBs) were incubated with Mtb-spiked PBS and saliva from healthy donors as well as with saliva from TB patients. Flow cytometry was used to evaluate the capacity of the beads to bind Mtb, while real-time quantitative polymerase chain reaction (qPCR) was utilized to detect Mtb and determine the amount of mycobacterial DNA in different sample types.

Results

We found that LMBs bind Mtb efficiently when compared to non-functionalized beads. The development of an qPCR assay based on the use of LMBs (LMB assay) allowed us to enrich mycobacterial DNA in spiked sample types, including PBS and saliva from healthy donors (enrichment of up to ~8.7 fold). In Mtb-spiked saliva samples, we found that the LMB assay improved the detection rate of 102 bacteria in a volume of 5 ml from 0 out of 15 (0%) to 6 out of 15 (40%). Consistent with that, the LMB assay increased the rate of correctly identified saliva samples from TB patients in two independent cohorts.

Conclusions

Implementation of the principle of the LMB-based assay may improve the sensitivity of existing diagnostic techniques, e.g. by functionalizing materials that facilitate Mtb sampling from the oral cavity.

Heightened microbial translocation is a prognostic biomarker of recurrent tuberculosis

BACKGROUND

Microbial translocation is a known characteristic of pulmonary tuberculosis (PTB). Whether microbial translocation is also a biomarker of recurrence in PTB is not known.

METHODS

We examined the presence of microbial translocation in a cohort of newly diagnosed, sputum smear and culture positive individuals with drug-sensitive PTB. Participants were followed up for a year following the end of anti-tuberculosis treatment. They were classified as cases (in the event of recurrence, n=30) and compared to age and gender matched controls (in the event of successful, recurrence free cure; n=51). Plasma samples were used to measure the circulating microbial translocation markers. All the enrolled study participants were treatment naïve, HIV negative and with or without diabetes mellitus.

RESULTS

Baseline levels of lipopolysaccharide (LPS) (p=0.0002), sCD14 (p=0.0191) and LPS-binding protein (LBP) (p<0.0001) were significantly higher in recurrence than controls and were associated with increased risk for recurrence, while Intestinal fatty acid binding protein (I-FABP) and Endocab showed no association. ROC curve analysis demonstrated the utility of these individual microbial markers in discriminating recurrence from cure with high sensitivity, specificity and AUC.

CONCLUSION

Recurrence following microbiological cure in PTB is characterized by heightened baseline microbial translocation. These markers can be used as a rapid prognostic tool for predicting recurrence in PTB.

Biomarkers that correlate with active pulmonary tuberculosis treatment response: a systematic review and meta-analysis

Current WHO recommendations for monitoring treatment response in adult pulmonary tuberculosis (TB) are sputum smear microscopy and/or culture conversion at the end of the intensive phase of treatment. These methods either have suboptimal accuracy or a long turnaround time. There is a need to identify alternative biomarkers to monitor TB treatment response. We conducted a systematic review of active pulmonary TB treatment monitoring biomarkers. We screened 9,739 articles published between 1 January 2008 and 31 December 2020, of which 77 met the inclusion criteria. When studies quantitatively reported biomarker levels, we meta-analyzed the average fold change in biomarkers from pretreatment to week 8 of treatment. We also performed a meta-analysis pooling the fold change since the previous time point collected. A total of 81 biomarkers were identified from 77 studies. Overall, these studies exhibited extensive heterogeneity with regard to TB treatment monitoring study design and data reporting. Among the biomarkers identified, C-reactive protein (CRP), interleukin-6 (IL-6), interferon gamma-induced protein 10 (IP-10), and tumor necrosis factor alpha (TNF-α) had sufficient data to analyze fold changes. All four biomarker levels decreased during the first 8 weeks of treatment relative to baseline and relative to previous time points collected. Based on limited data available, CRP, IL-6, IP-10, and TNF-α have been identified as biomarkers that should be further explored in the context of TB treatment monitoring. The extensive heterogeneity in TB treatment monitoring study design and reporting is a major barrier to evaluating the performance of novel biomarkers and tools for this use case. Guidance for designing and reporting treatment monitoring studies is urgently needed.

Drug-Resistant Tuberculosis Among Children: A Systematic Review and Meta-Analysis

Background: Drug-resistant tuberculosis (DR-TB), especially multidrug-resistant tuberculosis (MDR-TB) is a public health threat. Little is known about estimates of different profiles and rates of DR-TB among children globally. Methods: We did a systematic review and meta-analysis of observational studies reporting DR-TB among children by searching Embase, PubMed, and Scopus databases from January 1, 2000 to October 1, 2020. Publications reporting more than 60 children with bacteriological confirmed tuberculosis and phenotypical drug susceptibility testing (DST) results were included. Pooled proportions of MDR-TB and sub-analysis by age subgroups, regions, economical levels were performed. Results: We identified 4,063 studies, of which 37 were included. Of 23,652 pediatric TB patients, the proportions of DR-TB, MDR-TB, mono-resistant TB, polydrug resistant TB, extensively drug-resistant TB were 13.59% (1,964/14,453), 3.72% (881/23,652), 6.07% (529/8,719), 1.61% (119/7,361), 0.44% (30/6,763), respectively. The pooled proportion of MDR-TB among 23,652 children of 37 studies was 3.7% (95% CI, 3.5-4.0%). Rate of MDR-TB was much lower in high-income countries (1.8%) than that in lower-middle-income countries (6.3%) and upper-middle-income countries (7.3%). More specifically, the rates of MDR-TB were 1.7% in USA, 1.7% in UK, 2.9% in India, 6.0% in South Africa, 9.8% in China, respectively. Conclusions: The burden of DR-TB remains high in children, and there are potential associations between rates of pediatric MDR-TB and national economical levels. More interventions on child TB cases in low-income countries may be urgently needed in future.

Global emerging resistance in pediatric infections with TB, HIV, and gram-negative pathogens

Infants, children and adolescents are at risk of life-threatening, antimicrobial-resistant infections. Global burdens of drug-resistant TB, HIV and gram-negative pathogens have a particular impact on paediatric age groups, necessitating a paediatric-focused agenda to address emerging resistance. Dedicated approaches are needed to find, successfully treat and prevent resistant infections in paediatric populations worldwide. Challenges include the diagnosis and identification of resistant infections, limited access to novel antimicrobials or to paediatric-friendly formulations, limited access to research and clinical trials and implementation challenges related to prevention and successful completion of treatment. In this review, the particular complexities of emerging resistance in TB, HIV and gram-negative pathogens in children, with attention to both clinical and public health challenges, are highlighted. Key principles of a paediatric-focused agenda to address antimicrobial resistance are outlined. They include quality of care, increasing equitable access to key diagnostics, expanding antimicrobial stewardship and infection prevention across global settings, and health system strengthening. Increased access to research studies, including clinical trials, is needed. Further study and implementation of care models and strategies for child- or adolescent-centred management of infections such as HIV and TB can critically improve outcome and avoid development of resistance. As the current global pandemic of a novel coronavirus, SARS-CoV-2, threatens to disrupt health systems and services for vulnerable populations, this is a critical time to mitigate against a potential surge in the incidence of resistant infections.

Integrated TB and HIV care for Mozambican children: temporal trends, site-level determinants of performance, and recommendations for improved TB preventive treatment

BACKGROUND

Pediatric tuberculosis (TB), human immunodeficiency virus (HIV), and TB-HIV co-infection are health problems with evidence-based diagnostic and treatment algorithms that can reduce morbidity and mortality. Implementation and operational barriers affect adherence to guidelines in many resource-constrained settings, negatively affecting patient outcomes. This study aimed to assess performance in the pediatric HIV and TB care cascades in Mozambique.

METHODS

A retrospective analysis of routine PEPFAR site-level HIV and TB data from 2012 to 2016 was performed. Patients 0-14 years of age were included. Descriptive statistics were used to report trends in TB and HIV indicators. Linear regression was done to assess associations of site-level variables with performance in the pediatric TB and HIV care cascades using 2016 data.

RESULTS

Routine HIV testing and cotrimoxazole initiation for co-infected children in the TB program were nearly optimal at 99% and 96% in 2016, respectively. Antiretroviral therapy (ART) initiation was lower at 87%, but steadily improved from 2012 to 2016. From the HIV program, TB screening at the last consultation rose steadily over the study period, reaching 82% in 2016. The percentage of newly enrolled children who received either TB treatment or isoniazid preventive treatment (IPT) also steadily improved in all provinces, but in 2016 was only at 42% nationally. Larger volume sites were significantly more likely to complete the pediatric HIV and TB care cascades in 2016 (p value range 0.05 to < 0.001).

CONCLUSIONS

Mozambique has made significant strides in improving the pediatric care cascades for children with TB and HIV, but there were missed opportunities for TB diagnosis and prevention, with IPT utilization being particularly problematic. Strengthened TB/HIV programming that continues to focus on pediatric ART scale-up while improving delivery of TB preventive therapy, either with IPT or newer rifapentine-based regimens for age-eligible children, is needed.

TB Presenting as Recurrent Pneumonia in a HIV-Infected Infant in Central Viet Nam

We report on a six-month-old infant admitted to our intensive care unit (ICU) with recurrent severe pneumonia. The mother was infected with human immunodeficiency virus (HIV)-infected, but initially failed to disclose this to doctors. Neither did she report the grandmother of the child’s chronic coughing, likely due to tuberculosis (TB). The infant was diagnosed with X-pert MTB/RIF® confirmed TB and tested positive for HIV infection. Once a correct diagnosis was established, the child demonstrated good recovery with appropriate TB and antiretroviral treatment (ART). The case demonstrates the importance of including TB in the differential diagnosis for young children not responding to first-line pneumonia treatment, especially in TB endemic areas. Taking a meticulous TB and HIV exposure history, with careful consideration of potential social stigma, is essential. It also demonstrates how the inaccessibility of HIV results and the absence of a continuous patient record may jeopardize patient care.

Xpert MTB/RIF diagnosis of childhood tuberculosis from sputum and stool samples in a high TB-HIV-prevalent setting

The Xpert MTB/RIF assay is a major advance for diagnosis of tuberculosis (TB) in high-burden countries but is limited in children by their difficulty to produce sputum. We investigated TB in sputum and stool from children with the aim of improving paediatric TB diagnosis. A prospective cohort of children with presumptive TB, provided two sputum or induced sputum at enrolment in a regional referral hospital in Uganda. Stool was collected from those started on TB treatment. All specimen were tested for Xpert MTB/RIF, mycobacteria growth indicator tube (MGIT), Lowenstein Jensen cultures and microscopy (except stool). We compared TB detection between age categories and assessed the performance of Xpert MTB/RIF in sputum and stool. Of the 392 children enrolled, 357 (91.1%) produced at least one sputum sample. Sputum culture yield was 13/357 (3.6%): 3/109 (2.6%), 3/89 (3.2%), 3/101 (2.6%) and 4/44 (8.2%) among children of < 2, 2-5, ≥ 5-10 and > 10 years, respectively (p = 0.599). Xpert MTB/RIF yield was 14/350 (4.0%): 3/104 (2.9%), 4/92 (4.3%), 3/88 (2.9%) and 4/50 (.0%), respectively (p = 0.283). Sensitivity and specificity of Xpert MTB/RIF in sputum against sputum culture were 90.9% (95% CI 58.7-99.8) and 99.1% (99.1-99.8). In stool, it was 55.6% (21.2-86.3) and 98.2% (98.2-100) against Xpert MTB/RIF and culture in sputum. Only a minority of children had microbiologically confirmed TB with a higher proportion in children above 10 years. Although sensitivity of Xpert MTB/RIF in stool was low, with good optimization, it might be a good alternative to sputum in children.

Diagnosis of Tuberculosis Following World Health Organization-Recommended Criteria in Severely Malnourished Children Presenting With Pneumonia

Evidences on diagnosis of tuberculosis (TB) following the World Health Organization (WHO) criteria in children with severe acute malnutrition (SAM) are lacking. We sought to evaluate the WHO criteria for the diagnosis of TB in such children. In this prospective study, we enrolled SAM children aged <5 with radiological pneumonia. We collected induced sputum and gastric lavage for smear microscopy, mycobacterial culture, and Xpert MTB/RIF. Using the last 2 methods as the gold standard, we determined sensitivity, specificity, and positive and negative predictive values of WHO criteria (n = 388). However, Xpert MTB/RIF was performed on the last 214 children. Compared to mycobacterial culture-confirmed TB, sensitivity and specificity (95% confidence interval) of WHO criteria were 40 (14% to 73%) and 84 (80% to 87%), respectively. Compared to culture- and/or Xpert MTB/RIF-confirmed TB, the values were 22% (9% to 43%) and 83 (79% to 87%), respectively. Thus, the good specificity of the WHO criteria may help minimize overtreatment with anti-TB therapy in SAM children, especially in resource-limited settings.

[A case-series analysis of tuberculosis in pediatric patients treated in a tertiary level hospital]

BACKGROUND

Tuberculosis (TB) remains a challenge because severe forms occur most frequently in children under 5 years of age and the diagnosis is complex. The objective of this paper was to describe the clinical presentation, frequency, diagnostic methods used and response to treatment in children with TB treated at a tertiary level hospital.

METHODS

The study was retrospective and descriptive of a cohort of consecutive cases treated from January 2010 to December 2013. Ninety-three medical records of children diagnosed with TB according to the definition of the NOM-006-SSA2-2013 were reviewed. Descriptive statistics were used for the analysis.

RESULTS

From 93 children, 58% were male (mean age of 7 years), 97% with a history of BCG vaccination, and 6% had contact with a TB case. The most frequent clinical forms were pulmonary (30.1%), lymph node (24.7%), miliary/disseminated (16.1%), meningeal (13%), and osteal TB (7.5%). The most common symptoms were fever and weight loss (50% and 40%, respectively). BAAR and culture were positive in 26% and 7% of all cases, respectively. The histopathological study was conclusive in 90% of the cases. The treatment was successful in 94.6%, with not associated mortality.

CONCLUSIONS

The association of clinical symptoms with alterations in chest radiography and positive PPD are useful in establishing the presumptive diagnosis and an early and appropriate treatment.

Improving access to tuberculosis preventive therapy and treatment for children

Children suffer a huge burden of disease in tuberculosis (TB) endemic countries. This disease burden was largely invisible when TB control programmes focused exclusively on adults with sputum smear-positive disease. High-level advocacy and better data have improved visibility, but the establishment of functional paediatric TB programmes remains challenging. The key issues that limit children's access to TB preventive therapy and treatment in endemic areas are briefly discussed. Barriers to preventive therapy include (1) the perceived inability to rule out active disease, (2) fear of creating drug resistance, (3) non-implementation of existing guidelines in the absence of adequate monitoring, and (4) poor adherence with long preventive therapy courses. Barriers to TB treatment include (1) perceived diagnostic difficulties, (2) non-availability of chest radiography, (3) young children presenting to unprepared maternal and child health (MCH) services, and (4) the absence of child-friendly formulations. With drug-resistant disease there is currently no guidance on the use of preventive therapy and treatment is usually restricted to cases with bacteriologically confirmed disease, which excludes most young children from care, even if their likely source case has documented drug-resistant TB.

Global Burden of Childhood Tuberculosis

In 2015, the World Health Organization (WHO) declared tuberculosis (TB) to be responsible for more deaths than any other single infectious disease. The burden of TB among children has frequently been dismissed as relatively low with resulting deaths contributing very little to global under-five all-cause mortality, although without rigorous estimates of these statistics, the burden of childhood TB was, in reality, unknown. Recent work in the area has resulted in a WHO estimate of 1 million new cases of childhood TB in 2014 resulting in 136,000 deaths. Around 3% of these cases likely have multidrug-resistant TB and at least 40,000 are in HIV-infected children. TB is now thought to be a major or contributory cause of many deaths in children under five years old, despite not being recorded as such, and is likely in the top ten causes of global mortality in this age group. In particular, recent work has shown that TB is an under-lying cause of a substantial proportion of pneumonia deaths in TB-endemic countries. Childhood TB should be given higher priority: we need to identify children at greatest risk of TB disease and death and make more use of tools such as active case-finding and preventive therapy. TB is a preventable and treatable disease from which no child should die.

Dilemma of managing asymptomatic children referred with 'culture-confirmed' drug-resistant tuberculosis

BACKGROUND

The diagnosis of drug-resistant tuberculosis (DR-TB) in children is challenging and treatment is associated with many adverse effects.

OBJECTIVE

We aimed to assess if careful observation, without initiation of second-line treatment, is safe in asymptomatic children referred with 'culture-confirmed' DR-TB.

SETTING

KwaZulu-Natal, South Africa-an area with high burdens of HIV, TB and DR-TB.

DESIGN, INTERVENTION AND MAIN OUTCOME MEASURES

We performed an outcome review of children with 'culture-confirmed' DR-TB who were not initiated on second-line TB treatment, as they were asymptomatic with normal chest radiographs on examination at our specialist referral hospital. Children were followed up every other month for the first year, with a final outcome assessment at the end of the study.

RESULTS

In total, 43 asymptomatic children with normal chest radiographs were reviewed. The median length of follow-up until final evaluation was 549 days (IQR 259-722 days); most (34; 83%) children were HIV uninfected. Resistance patterns included 9 (21%) monoresistant and 34 (79%) multidrug-resistant (MDR) strains. Fifteen children (35%) had been treated with first-line TB treatment, prior to presentation at our referral hospital. At the final evaluation, 34 (80%) children were well, 7 (16%) were lost to follow-up, 1 (2%) received MDR-TB treatment and 1 (2%) died of unknown causes. The child who received MDR-TB treatment developed new symptoms at the 12-month review and responded well to second-line treatment.

CONCLUSIONS

Bacteriological evaluation should not be performed in the absence of any clinical indication. If drug-resistant Mycobacterium tuberculosis is detected in an asymptomatic child with a normal chest radiograph, close observation may be an appropriate strategy, especially in settings where potential laboratory error and poor record keeping are constant challenges.

Current status of new tuberculosis vaccine in children

Pediatric tuberculosis contributes significantly to the burden of TB disease worldwide. In order to achieve the goal of eliminating TB by 2050, an effective TB vaccine is urgently needed to prevent TB transmission in children. BCG vaccination can protect children from the severe types of TB such as TB meningitis and miliary TB, while its efficacy against pediatric pulmonary TB ranged from no protection to very high protection. In recent decades, multiple new vaccine candidates have been developed, and shown encouraging safety and immunogenicity in the preclinical experiments. However, the limited data on protective efficacy in infants evaluated by clinical trials has been disappointing, an example being MVA85A. To date, no vaccine has been shown to be clinically safer and more effective than the presently licensed BCG vaccine. Hence, before a new vaccine is developed with more promising efficacy, we must reconsider how to better use the current BCG vaccine to maximize its effectiveness in children.

Setting priorities for a research agenda to combat drug-resistant tuberculosis in children

SETTING

Numerous knowledge gaps hamper the prevention and treatment of childhood drug-resistant tuberculosis (TB). Identifying research priorities is vital to inform and develop strategies to address this neglected problem.

OBJECTIVE

To systematically identify and rank research priorities in childhood drug-resistant TB.

DESIGN

Adapting the Child Health and Nutrition Research Initiative (CHNRI) methodology, we compiled 53 research questions in four research areas, then classified the questions into three research types. We invited experts in childhood drug-resistant TB to score these questions through an online survey.

RESULTS

A total of 81 respondents participated in the survey. The top-ranked research question was to identify the best combination of existing diagnostic tools for early diagnosis. Highly ranked treatment-related questions centred on the reasons for and interventions to improve treatment outcomes, adverse effects of drugs and optimal treatment duration. The prevalence of drug-resistant TB was the highest-ranked question in the epidemiology area. The development type questions that ranked highest focused on interventions for optimal diagnosis, treatment and modalities for treatment delivery.

CONCLUSION

This is the first effort to identify and rank research priorities for childhood drug-resistant TB. The result is a resource to guide research to improve prevention and treatment of drug-resistant TB in children.

Understanding Market Size and Reporting Gaps for Paediatric TB in Indonesia, Nigeria and Pakistan: Supporting Improved Treatment of Childhood TB in the Advent of New Medicines

Objective of the Study

We sought to understand gaps in reporting childhood TB cases among public and private sector health facilities (dubbed “non-NTP” facilities) outside the network of national TB control programmes, and the resulting impact of under-reporting on estimates of paediatric disease burden and market demand for new medicines.

Methodology

Exploratory assessments were carried out in Indonesia, Nigeria and Pakistan, reaching a range of facility types in two selected areas of each country. Record reviews and interviews of healthcare providers were carried out to assess numbers of unreported paediatric TB cases, diagnostic pathways followed and treatment regimens prescribed.

Main Findings

A total of 985 unreported diagnosed paediatric TB cases were identified over a three month period in 2013 in Indonesia from 64 facilities, 463 in Pakistan from 35 facilities and 24 in Nigeria from 20 facilities. These represent an absolute additional annualised yield to 2013 notifications reported to WHO of 15% for Indonesia, 2% for Nigeria and 7% for Pakistan. Only 12% of all facilities provided age and sex-disaggregated data. Findings highlight the challenges of confirming childhood TB. Diagnosis patterns in Nigeria highlight a very low suspicion for childhood TB. Providers note the need for paediatric medicines aligned to WHO recommendations.

Conclusion: How Market Data Can Support Better Public Health Interventions

This study emphasises the impact of incomplete reporting on the estimation of disease burden and potential market size of paediatric TB medicines. Further studies on “hubs” (facilities treating large numbers of childhood TB cases) will improve our understanding of the epidemic, support introduction efforts for new treatments and better measure markets for new paediatric medicines.

Sociodemographic, Epidemiological, and Clinical Risk Factors for Childhood Pulmonary Tuberculosis in Severely Malnourished Children Presenting With Pneumonia: Observation in an Urban Hospital in Bangladesh

We aimed to evaluate sociodemographic, epidemiological, and clinical risk factors for pulmonary tuberculosis (PTB) in children presenting with severe acute malnutrition (SAM) and pneumonia. Children aged 0 to 59 months with SAM and radiologic pneumonia from April 2011 to July 2012 were studied in Bangladesh. Children with confirmed PTB (by culture and/or X-pert MTB/RIF) (cases = 27) and without PTB (controls = 81; randomly selected from 378 children) were compared. The cases more often had the history of contact with active PTB patient (P < .01) and exposure to cigarette smoke (P = .04) compared with the controls. In logistic regression analysis, after adjusting for potential confounders, the cases were independently associated with working mother (P = .05) and positive tuberculin skin test (TST; P = .02). Thus, pneumonia in SAM children is a common presentation of PTB and further highlights the importance of the use of simple TST and/or history of contact with active TB patients in diagnosing PTB in such children, especially in resource-limited settings.

Cross Sectional Study Evaluating Routine Contact Investigation in Addis Ababa, Ethiopia: A Missed Opportunity to Prevent Tuberculosis in Children

The 2013 global roadmap for childhood tuberculosis calls for countries to implement contact screening and provide preventive therapy to children younger than 5 years. Therefore, this study designed to evaluate the implementation status of child contact screening and management in the health facilities of Addis Ababa, Ethiopia. Smear positive TB patients living with children attending daily observed treatment at the TB clinic and health care workers providing service were approached to address the study objective. Structured questionnaires were administered to smear positive index cases living with children whether they were requested to bring children age five year and below for TB screening and to health care providers in HIV, TB and child health clinics to assess their knowledge and practice on contact screening and management. Double data entry and analysis was done using EpiData software 3.1. In 27 health centres, 688 smear-positive index tuberculosis patients were approached of whom 203 (29.5%) reported to have children five years and below in their household. A total of 48 (23.6%) index cases had been requested by the health care workers to bring their children for tuberculosis screening and 45 (93.8%) had complied with this request. Of 230 children living with index smear positive tuberculosis patient, 152 (66.1%) were not screened for tuberculosis, 78 (33.9%) children screened, 2 had tuberculosis, 76 screened negative of which 3 (3.8%) received preventive treatment. None of the health care workers indicated to routinely record and report on child contact management. Household child contact screening and preventive intervention was sub-optimal in Addis Ababa. An important opportunity lost to prevent tuberculosis in young children. Training of health care workers, availing simple symptom based screening tool, and proper documentation could improve implementation.

Validity of antibodies in lymphocyte supernatant in diagnosing tuberculosis in severely malnourished children presenting with pneumonia

Background

The diagnosis of tuberculosis (TB) in young children can be challenging, especially in severely malnourished children. There is a critical need for improved diagnostics for children. Thus, we sought to evaluate the performance of a technique that measures antibodies in lymphocyte supernatant (ALS) for the diagnosis of TB in severely malnourished children presenting with suspected pneumonia.

Methods

Children less than 5 years with severe acute malnutrition and radiological features of pneumonia admitted to the Dhaka Hospital of International Centre for Diarrhoeal Disease Research, Bangladesh, were enrolled consecutively following informed written consent. In addition to clinical and radiological assessment, samples taken for TB diagnosis included gastric lavage fluid and induced sputum for microbiological confirmation. ALS was measured from venous blood, and results were evaluated in children classified as “confirmed”, “non-confirmed TB” or “not TB”.

Results

Among 224 children who had ALS analysis, 12 (5.4%) children had microbiologically “confirmed TB”, a further 41 (18%) had clinically diagnosed “non-confirmed TB” and the remaining 168 (75%) were considered not to have TB. ALS was positive in 89 (40%) and negative in 85 (39%) of children, with a large number (47 or 21%) reported as “borderline”. These proportions were similar between the three diagnostic groups. The sensitivity and specificity of ALS when comparing “Confirmed TB” to “Not TB” was only 67% (95% CI: 31–91%) and 51% (95% CI: 42–60%), respectively.

Conclusions and Significance

Our data suggest that ALS is not sufficiently accurate to improve the diagnosis of TB in children with severe malnutrition.

[Management of multidrug-resistant tuberculosis]

The emergence of drug-resistant TB in many countries has become a major public health problem and an obstacle to effective tuberculosis control. Multidrug-resistant tuberculosis (MDR-TB), which is most often the result of poor adherence, is a particularly dangerous form of tuberculosis because it is caused by bacilli resistant to at least isoniazid and rifampicin, the two most effective anti-tuberculosis drugs. Techniques for rapid diagnosis of resistance have greatly improved the care of patients by allowing early treatment which remains complex and costly establishment, and requires skills and resources. The treatment is not standardized but it includes in all cases attack phase with five drugs (there must be an injectable agent and a fluoroquinolone that form the basis of the regimen) for eight months and a maintenance phase (without injectable agent) with a total duration of 20 months on average. Surgery may be beneficial as long as the lesions are localized and the patient has a good cardiorespiratory function. Evolution of MDR-TB treated is less favorable than tuberculosis with germ sensitive. The cure rate varies from 60 to 75% for MDR-TB, and drops to 30 to 40% for XDR-TB. Mortality remains high, ranging from 20 to 40% even up to 70-90% in people co-infected with HIV.

Assessing the consequences of stigma for tuberculosis patients in urban Zambia

BACKGROUND

Stigma is one of the many factors hindering tuberculosis (TB) control by negatively affecting hospital delay and treatment compliance. In Zambia, the morbidity and mortality due to TB remains high, despite extended public health attempts to control the epidemic and to diminish stigma.

STUDY AIM

To enhance understanding of TB-related stigmatizing perceptions and to describe TB patients' experiences of stigma in order to point out recommendations to improve TB policy.

METHODS

We conducted a mixed method study at Kanyama clinic and surrounding areas, in Lusaka, Zambia; structured interviews with 300 TB patients, multiple in-depth interviews with 30 TB patients and 10 biomedical health workers, 3 focus group discussions with TB patients and treatment supporters, complemented by participant observation and policy analysis of the TB control program. Predictors of stigma were identified by use of multivariate regression analyses; qualitative analysis of the in-depth interviews, focus group discussions and participant observation was used for triangulation of the study findings.

RESULTS

We focused on the 138/300 patients that described TB-related perceptions and attitudes, of whom 113 (82%) reported stigma. Stigma provoking TB conceptions were associated with human immunodeficiency virus (HIV)-infection, alleged immoral behaviour, (perceived) incurability, and (traditional) myths about TB aetiology. Consequences of stigma prevailed both among children and adults and included low self-esteem, insults, ridicule, discrimination, social exclusion, and isolation leading to a decreased quality of life and social status, non-disclosure, and/or difficulties with treatment compliance and adherence. Women had significantly more stigma-related problems than men.

CONCLUSIONS

The findings illustrate that many TB patients faced stigma-related issues, often hindering effective TB control and suggesting that current efforts to reduce stigma are not yet optimal. The content and implementation of sensitization programs should be improved and more emphasis needs to be placed on women and children.

Map the gap: missing children with drug-resistant tuberculosis

BACKGROUND

The lack of published information about children with multidrug-resistant tuberculosis (MDR-TB) is an obstacle to efforts to advocate for better diagnostics and treatment.

OBJECTIVE

To describe the lack of recognition in the published literature of MDR-TB and extensively drug-resistant TB (XDR-TB) in children.

DESIGN

We conducted a systematic search of the literature published in countries that reported any MDR- or XDR-TB case by 2012 to identify MDR- or XDR-TB cases in adults and in children.

RESULTS

Of 184 countries and territories that reported any case of MDR-TB during 2005-2012, we identified adult MDR-TB cases in the published literature in 143 (78%) countries and pediatric MDR-TB cases in 78 (42%) countries. Of the 92 countries that reported any case of XDR-TB, we identified adult XDR-TB cases in the published literature in 55 (60%) countries and pediatric XDR-TB cases for 9 (10%) countries.

CONCLUSION

The absence of publications documenting child MDR- and XDR-TB cases in settings where MDR- and XDR-TB in adults have been reported indicates both exclusion of childhood disease from the public discourse on drug-resistant TB and likely underdetection of sick children. Our results highlight a large-scale lack of awareness about children with MDR- and XDR-TB.

Prevalence of drug resistant Mycobacterium tuberculosis among children in China

The available data on the epidemic of drug resistant tuberculosis (TB) among children in China is limited. This study attempted to clarify the drug resistance profiles of clinical strains isolated from children and estimate risk factors related to acquisition of drug resistance. All Mycobacterium tuberculosis strains from children (age <15 years) and adolescent (age 15-18 years) TB patients received in the strain library of Chinese Center for Disease Control and Prevention between January 2005 and December 2012 were included in the study. A study collection included 450 clinical isolates (100 from children, 159 from adolescents, and 191 from adults) from all over China. Drug susceptibility testing was performed by a proportion method. As a result, the drug resistance and multi-drug resistance (MDR) rates in children were 55% (55/100) and 22% (22/100), respectively. In children with MDR-TB, new cases accounted for 40.9% (9/22). Compared with adults, the drug resistance rates were similar in all subgroups (new cases, previously treated cases and all cases) of children (P > 0.05), except for the lower resistance rate to isoniazid in total cases of children (P = 0.011). Patient related information was included in the MDR-TB association analysis. The treatment history was found to be strongly associated with MDR-TB in all three age groups (P < 0.05). Our results demonstrate that the prevalence of drug resistant TB in children in China is alarmingly high and similar to that seen in adults. In contrast, in adolescents, the drug resistance rate to most tested drugs was lower than in adults. Primary transmission and inadequate treatment are two equally important factors for the high MDR-TB rate in children. Thus, major efforts in the TB control in children should focus on decreasing the transmission of drug resistant TB and early testing of drug resistance.

Evaluation of health-care providers' knowledge of childhood tuberculosis in Lima, Peru

BACKGROUND

As most national tuberculosis programmes (NTPs) focus on adult tuberculosis (TB), NTP providers may not appreciate differences in the pathophysiology and presentation of childhood TB.

OBJECTIVES

This study aimed to identify strengths and weaknesses in knowledge of childhood TB among the 326 NTP providers in Lima Ciudad and Lima Este--two of the Peruvian capital's four health districts.

METHODS

310 providers--103 physicians, 106 nurses, 101 nursing technicians--accepted personal invitations to complete self-administered surveys, which included 14 childhood TB questions grouped into five sections: transmission, symptoms, diagnosis, prevention and treatment. Physicians were asked ten additional questions targeting their NTP diagnostic and management responsibilities.

RESULTS

All three groups scored 97-99% on the transmission section and 83-85% on the treatment section; however, no group scored above 66% on any other section. Fewer than 50% of nurses and technicians recognised young children's high risk of extrapulmonary TB, extrapulmonary TB symptoms or the causes of false negative tuberculin skin tests. Twenty-three per cent of physicians correctly identified gastric aspirate culture sensitivity, and 42% the radiographical findings of pulmonary TB. Less than two-thirds of providers recognised the definition of latent TB infection (LTBI), young children's high risk of progression from LTBI to disease or indications for isoniazid preventive therapy.

CONCLUSIONS

Providers at the frontline of Peru's TB control efforts demonstrated weaknesses in the areas of extrapulmonary disease, diagnosis and prevention. These knowledge gaps are likely to have resulted in delayed or missed diagnoses and lost opportunities for prevention. Educational interventions targeting NTP personnel may improve childhood TB care and outcomes.

Tuberculosis in HIV-infected infants, children, and adolescents in Latin America

OBJECTIVE

To evaluate the occurrence, clinical presentations and diagnostic methods for tuberculosis in a cohort of HIV-infected infants, children and adolescents from Latin America.

METHODS

A retrospective analysis of children with tuberculosis and HIV was performed within a prospective observational cohort study conducted at multiple clinical sites in Latin America.

RESULTS

Of 1114 HIV-infected infants, children, and adolescents followed from 2002 to 2011, 69 that could be classified as having confirmed or presumed tuberculosis were included in this case series; 52.2% (95% CI: 39.8-64.4%) had laboratory-confirmed tuberculosis, 15.9% (95% CI: 8.2-26.7%) had clinically confirmed disease and 31.9% (95% CI: 21.2-44.2%) had presumed tuberculosis. Sixty-six were perinatally HIV-infected. Thirty-two (61.5%) children had a history of contact with an adult tuberculosis case; however information on exposure to active tuberculosis was missing for 17 participants. At the time of tuberculosis diagnosis, 39 were receiving antiretroviral therapy. Sixteen of these cases may have represented immune reconstitution inflammatory syndrome.

CONCLUSIONS

Our study emphasizes the need for adequate contact tracing of adult tuberculosis cases and screening for HIV or tuberculosis in Latin American children diagnosed with either condition. Preventive strategies in tuberculosis-exposed, HIV-infected children should be optimized.

Commentary: a targets framework: dismantling the invisibility trap for children with drug-resistant tuberculosis

Tuberculosis (TB) is an airborne infectious disease that is both preventable and curable, yet it kills more than a million people every year. Children are highly vulnerable, but often invisible casualties. Drug-resistant forms of TB are on the rise globally, and children are as vulnerable as adults but less likely to be counted as cases of drug-resistant disease if they become sick. Four factors make children with drug-resistant TB 'invisible': first, the nature of the disease in children; second, deficiencies in existing diagnostic tools; third, overreliance on these tools; and fourth, our collective failure to deploy one effective tool for finding and treating children - contact investigation. We describe a nascent science-advocacy network - the Sentinel Project on Pediatric Drug-Resistant Tuberculosis - whose goal is to end child deaths from this disease. Provisional annual targets, focused on children exposed at home to multidrug-resistant TB, to be updated every year, constitute a framework to focus attention and collective actions at the community, national, and global levels. The targets in two age groups, under 5 and 5-14 years old, tell us the number of: (i) children who require complete evaluation for TB disease and infection; (ii) children who require treatment for TB disease; and (iii) children who would benefit from preventive therapy.

Rapid diagnosis of childhood pulmonary tuberculosis by Xpert MTB/RIF assay using bronchoalveolar lavage fluid

In order to evaluate the diagnostic accuracy of the Xpert MTB/RIF assay on childhood pulmonary tuberculosis (PTB) using bronchoalveolar lavage fluid (BALF), we evaluated the sensitivity, specificity, positive predictive value, and negative predictive value of Xpert MTB/RIF assay using BALF in comparison with acid-fast bacilli (AFB) microscopy and Mycobacterium tuberculosis (MTB) culture for diagnosing childhood PTB using Chinese “composite clinical reference standard” (CCRS) as reference standard. Two hundred fifty-five children with suspected PTB were enrolled at Beijing Children's Hospital from September 2010 to July 2013. Compared with Chinese CCRS, the sensitivity of AFB microscopy, MTB culture, and Xpert MTB/RIF assay was 8.4%, 28.9%, and 53.0%, respectively. The specificity of three assays was all 100%. Xpert MTB/RIF assay could detect 33.9% of cases with negative MTB culture, and 48.7% of cases with negative AFB microscopy. Younger age (<3 years), absence of BCG scar, and contact with TB patient were found significantly associated with a positive result of Xpert MTB/RIF assay. In conclusion, Xpert MTB/RIF assay using BALF can assist in diagnosing childhood PTB much faster when fiberoptic bronchoscopy is necessary according to the chest radiograph.

Assessing the impact of multidrug-resistant tuberculosis in children: an exploratory qualitative study

BACKGROUND

While the prevalence of multidrug-resistant (MDR) tuberculosis (TB) is high among children in the Western Cape of South Africa, the psychosocial implications of treatment for children with MDR-TB remain poorly understood. We sought to explore how MDR-TB and its treatment impact children on an individual, familial, and social level.

METHODS

Semi-structured interviews were conducted with 20 children and caregivers purposively sampled from a prospective clinical cohort of children. The sample was stratified by age at the start of treatment (children >10 years, and 5-10 years). Caregiver proxy interviews were conducted with younger children, supplemented with child interviews; older children were interviewed directly, supplemented with caregiver proxy interviews. Data were analysed using grounded theory.

RESULTS

Findings revealed pill volume and adverse effects produced significant physical, psychological and academic disturbances in children. Adverse effects related to the medication were important obstacles to treatment adherence. While there appear to be no long-lasting effects in younger children, a few older children showed evidence of persisting internalised stigma. Caregivers suffered important treatment-related financial and psychological costs. Community support, notably through the continued involvement of children in strong social networks, promoted resilience among children and their families.

CONCLUSIONS

We found that the current treatment regimen for childhood MDR-TB has significant psychological, academic, and financial impacts on children and their families. There is a need for psychosocial support of children and caregivers to mitigate the negative effects of community stigma, and to manage the stressors associated with chronic illness.

Diagnosis of paediatric tuberculosis using sputum induction in Botswana: programme description and findings

SETTING

Four public hospitals in Botswana, a high tuberculosis (TB) burden setting.

OBJECTIVES

To assess the feasibility and utility of sputum induction in the diagnosis of paediatric TB.

DESIGN

From 2008 to 2010, children aged ≤18 years referred for suspected pulmonary TB underwent sputum induction. Confirmed TB was defined as the presence of at least one of the signs and symptoms suggestive of TB and positive Mycobacterium tuberculosis culture. Information on TB-associated symptoms (cough, fatigue, night sweats, low appetite, chest pain, weight loss, haemoptysis and contact with a TB case) was collected for three risk groups: human immunodeficiency virus (HIV) positive children, HIV-negative children aged <3 years and HIV-negative children aged ≥3 years.

RESULTS

The median age of the 1394 subjects who underwent sputum induction was 3.8 years (IQR 1.3-8.4); 373 (27%) were HIV-positive, 419 (30%) were HIV-negative and 602 (43%) had unknown HIV status. TB was confirmed in 84 (6.0%); cases were more likely to have weight loss, chest pain or TB household contacts. There were no serious complications attributable to sputum induction during and after the procedure; only 0.8% (9/1174) of patients reported minor complications.

CONCLUSIONS

In Botswana, paediatric sputum induction was feasible, safe and assisted bacteriological confirmation in a subgroup of children treated for TB.

Yield of contact tracing from pediatric tuberculosis index cases in Gaborone, Botswana

SETTING

Contact tracing using pediatric index cases has not been adequately investigated in high tuberculosis (TB) and human immunodeficiency virus (HIV) prevalence settings.

OBJECTIVE

To determine the yield of contact tracing in household contacts of pediatric TB index cases in Botswana.

DESIGN

Index cases included all pediatric (age ≤ 13 years) TB admissions from January 2009 to December 2011 to Botswana's largest referral hospital. A contact tracing team identified cases, conducted home visits, symptom-screened contacts and referred those with ≥ 1 TB symptoms. The primary outcome was newly diagnosed TB in a contact.

RESULTS

From 163 pediatric index cases, 548 contacts were screened (median 3 contacts/case, interquartile range [IQR] 2-4). Of these, 49 (9%) were referred for positive symptoms on screening and 27/49 (55%) were evaluated for active TB. Twelve new TB cases were diagnosed (12/548, 2.2%); the median age was 31 years (IQR 23-38); 11 (92%) were smear-positive. Ten (83%) had known HIV status: 7 (70%) were HIV-positive. To find one new TB case, the number needed to contact trace (index cases/new cases) was 13.6, and the number needed to screen (contacts/new cases) was 46.

CONCLUSION

This yield of contact tracing using pediatric index cases is similar to the traditional adult index case approach. Improving the proportion of symptomatic contacts evaluated may increase yield.

Intermittent versus daily therapy for treating tuberculosis in children

BACKGROUND

Childhood tuberculosis (TB) is a neglected global public health problem. Short treatment courses with rifampicin-containing anti-TB drugs given daily for six-months cure over 90% of infected children, but poor adherence reduces treatment success. Intermittent, short-course anti-TB regimens, given two or three times a week under direct observation, are associated with higher adherence in observational studies; but how they compare with daily treatment in relation to cure is unclear. Current international and national recommendations differ on use of intermittent regimens to treat TB in children.

OBJECTIVES

To compare the efficacy and safety of intermittent, short-course anti-TB regimens (twice- or thrice-weekly) with daily short-course anti-TB regimens in treating childhood TB.

SEARCH METHODS

We searched the Cochrane Infectious Disease Group Specialized Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, LILACS, clinical trials registries, regional databases, conference proceedings, and references without language restrictions up to 30 May 2013; and contacted experts for relevant published, unpublished, and on-going trials.

SELECTION CRITERIA

Randomized controlled trials (RCTs) and quasi-RCTs of children aged 15 years or younger, diagnosed with TB (according to the World Health Organization diagnostic categories 1, 2, or 3), who were treated with intermittent twice-weekly or thrice-weekly, short-course anti-TB regimens compared to daily short-course anti-TB treatment regimens. All regimens had to contain rifampicin for at least the first two months.

DATA COLLECTION AND ANALYSIS

The review authors independently screened and selected trials, assessed risk of bias, and extracted data. We sought clarifications from trial authors. We pooled relative risks with their 95% confidence intervals and used a random-effects model where there was significant heterogeneity. We assessed overall evidence-quality using the GRADE approach.

MAIN RESULTS

We included four trials published between 1996 to 2000 that randomized 563 children (465 evaluable) aged five months to 15 years to intermittent twice-weekly versus daily anti-TB treatment. Two trials were from India, one from South Africa, and one from Turkey. All trials used rifampicin and isoniazid, three trials used pyrazinamide, and one trial used streptomycin. The drug combination, and the duration of intermittent and daily treatments differed between trials, and no trials used drug combinations and schedules currently recommended for childhood TB. No trial reported if any child was HIV-positive.In comparisons of twice-weekly versus daily anti-TB treatment regimens, the trials did not detect differences in the number of patients cured, but trials were small, and the comparator regimens were not standard (four trials, 465 children; very low quality evidence). Trials were underpowered to provide estimates for death (two trials, 213 participants, very low quality evidence), relapse (one trial, 214 participants,very low quality evidence), and treatment limiting adverse events (four trials, 441 participants, very low quality evidence)Reported adherence to treatment was similar (87% versus 84%; four trials, 458 children, very low quality evidence)We did not find trials comparing the commonly used thrice-weekly anti-TB short-course regimen with the daily treatment regimen.

AUTHORS' CONCLUSIONS

Trials conducted to date are insufficient to support or refute the use of intermittent twice- or thrice-weekly, short-course treatment regimens over daily short-course treatment in children with TB. Further randomized trials conducted in high TB-transmission settings will help inform policy and practice.

Paediatric travel medicine: vaccines and medications

The paediatric aspects of travel medicine can be complex, and individual advice is often required. Nonetheless, children are much more likely to acquire common infections than exotic tropical diseases whilst travelling. Important exceptions are malaria and tuberculosis, which are more frequent and severe in children. Overall, travellers' diarrhoea is the most common illness affecting travellers. This review discusses vaccines and medications that may be indicated for children who are travelling overseas. It focuses on immunizations that are given as part of the routine schedule, as well as those that are more specific to travel. Malaria and travellers' diarrhoea are also discussed.

Intensified specimen collection to improve tuberculosis diagnosis in children from Rural South Africa, an observational study

BACKGROUND

In drug-resistant TB settings, specimen collection is critical for drug-susceptibility testing (DST). This observational study included multiple specimen types collected from pediatric TB suspects with the aim to determine diagnostic yield and inform clinical practice in children with drug-resistant and drug-susceptible TB.

METHODS

From 03/2009-07/2010, TB suspects aged ≥6 months and ≤12 years were recruited among outpatient and inpatient settings. Subjects were new TB suspects or had persistent symptoms despite ≥2 months of TB treatment. The protocol included collection of a single blood and urine specimen, a single sputum induction and, if inpatients and <5 years of age, collection of 3 gastric aspirates (GA). Samples were cultured on solid and/or liquid media. DST was by 1% proportion method.

RESULTS

Among 118 children with possible, probable or confirmed TB, the mean age was 4.9 years [SD 3.2] and 64 (62%) of those tested were HIV-positive. Eight (7%) subjects were culture-positive from at least one specimen; yield did not differ by HIV status or TB treatment history. Among those with positive cultures, 7/8 (88%) were from induced sputum, 5/6 (83%) from GA, 3/8 (38%) from blood, and 3/7 (43%) from urine. In subjects with both induced sputum and GA collection, sputum provided one additional case compared to GA. Multidrug resistant (MDR)-TB was detected by urine culture alone in one child >5 years old. Pan-resistant extensively drug resistant (XDR)-TB was identified by cultures from all sites in one subject.

CONCLUSIONS

TB was cultured from HIV-positive and -negative children, and allowed for identification of MDR and XDR-TB cases. Urine and induced sputum each provided an additional TB diagnosis and, when compared to GA, may be considered a less invasive, same-day method of specimen collection for childhood TB suspects. This study illustrates the continued challenges and limitations of available strategies for pediatric TB diagnostics.

Risk factors for mortality in Malawian children with human immunodeficiency virus and tuberculosis co-infection

SETTING

A large urban pediatric human immunodeficiency virus (HIV) clinic in Lilongwe, Malawi.

OBJECTIVE

To identify demographic and clinical risk factors for mortality in children co-infected with HIV and tuberculosis (TB).

DESIGN

A retrospective cohort study of HIV-infected children (aged <18 years) enrolled between October 2004 and October 2010 with at least one current or historical TB diagnosis. Descriptive statistics and logistic regression analyses were performed to determine factors associated with mortality.

RESULTS

A total of 1561 patients met the inclusion criteria, representing 32% of patients ever enrolled. Median age at TB diagnosis was 3.8 years (interquartile range 1.5-7.4); 60.9% had severe immune suppression and 47.6% of those with available data had some degree of acute malnutrition at TB diagnosis. Of the 1113 patients with known outcomes, 225 (20.2%) died. Children with TB-HIV co-infection not initiated on antiretroviral therapy (ART) at any time were 8.8 times more likely to die compared to those initiated on ART 0-2 months after initiation of anti-tuberculosis treatment (adjusted OR 8.83, 95%CI 4.42-17.63). Severe immunosuppression and World Health Organization Stage IV were also associated with mortality.

CONCLUSIONS

Pediatric TB-HIV co-infection is common and mortality is high in this cohort of Malawian children. Prompt initiation of ART should be emphasized in this high-risk patient population.

Childhood tuberculosis: epidemiology, diagnosis, treatment, and vaccination

Despite the existence of a government-run tuberculosis (TB) control program, the current nationwide burden of TB continues to be a public health problem in Taiwan. Intense current and previous efforts into diagnostic, therapeutic, and preventive interventions have focused on TB in adults, but childhood TB has been relatively neglected. Children are particularly vulnerable to severe disease and death following infection, and children with latent infections become reservoirs for future transmission following disease reactivation in adulthood, thus fueling future epidemics. Additional research, understanding, and prevention of childhood TB are urgently needed. This review assesses the epidemiology, diagnosis, treatment, and relevant principles of TB vaccine development and presents efficacy data for the currently licensed vaccines.

Spectrum of Disease in Children Treated for Tuberculosis at a Tertiary Children's Hospital in Australia

BACKGROUND

Tuberculosis (TB) notification rates in Australia have plateaued at a low level, but the pediatric disease burden remains poorly described. Child cases provide a marker of recent transmission and present unique diagnostic challenges.

METHODS

We performed an audit of all children (<18 years of age) treated for TB at the Children's Hospital at Westmead, Sydney, Australia from January 2008 to December 2011. Demographics, clinical presentation, diagnostics, disease profile, treatment, and outcome were reviewed.

RESULTS

A total of 25 children were treated for TB: 15 had microbiologically confirmed TB; 7 were diagnosed on clinical grounds; and in 3, an alternate diagnosis was established (2 bacille Calmette-Guérin disease and 1 atypical mycobacterial infection). Of the 22 TB cases, 21 had a history of immigration or travel to a TB-endemic country and 4 reported recent contact with a TB source case within Australia. Isolated intrathoracic TB was documented in 16 (72%) cases. Symptoms on presentation included the following: lethargy, weakness, or malaise (75%); fever (73%); and cough (64%). Among the 15 children with microbiologically confirmed TB, 11 (73%) were positive by culture and 11 of 13 (85%) by polymerase chain reaction test. Tuberculin skin test was positive (≥10 mm) in 80% (16 of 20) of cases, and interferon-gamma release assay was positive in 87% (13 of 15) of cases. All children received directly observed therapy and recovered.

CONCLUSIONS

This series demonstrates the broad spectrum of disease with which pediatric TB cases present and the need for ongoing vigilance. A more comprehensive review of pediatric TB cases throughout Australia would be informative.

Consensus Statement on Research Definitions for Drug-Resistant Tuberculosis in Children

Few children with drug-resistant (DR) tuberculosis (TB) are identified, diagnosed, and given an appropriate treatment. The few studies that have described this vulnerable population have used inconsistent definitions. The World Health Organization (WHO) definitions used for adults with DR-TB and for children with drug-susceptible TB are not always appropriate for children with DR-TB. The Sentinel Project on Pediatric Drug-Resistant Tuberculosis was formed in 2011 as a network of experts and stakeholders in childhood DR-TB. An early priority was to establish standardized definitions for key parameters in order to facilitate study comparisons and the development of an evidence base to guide future clinical management. This consensus statement proposes standardized definitions to be used in research. In particular, it suggests consistent terminology, as well as definitions for measures of exposure, drug resistance testing, previous episodes and treatment, certainty of diagnosis, site and severity of disease, adverse events, and treatment outcome.

Multidrug-resistant tuberculosis in children: evidence from global surveillance

Multidrug-resistant tuberculosis (MDR-TB) can affect persons of any age, but it remains unknown whether children are more or less likely than adults to have MDR-TB.

Representative drug resistance surveillance data reported to the World Health Organization between 1994 and 2011 were analysed to test the association between MDR-TB and age group (children aged <15 years versus adults aged ≥15 years), using odds ratios derived by logistic regression with robust standard errors.

Of 85 countries with data from nationwide surveys or surveillance systems, 35 reported at least one paediatric MDR-TB case. Aggregated data on age and drug susceptibility testing for 323 046 tuberculosis cases notified in these 35 countries were analysed. Odds ratios for MDR-TB in children compared to adults varied widely between countries. In Germany, Namibia, South Africa, the UK and the USA, MDR-TB was positively associated with age <15 years. In the remaining countries no association was established.

Despite the limitations intrinsic to the use of surveillance data and to the challenges of diagnosing childhood tuberculosis, our analysis suggests that proportions of MDR-TB in children and adults are similar in many settings. Of particular concern is the association found between age <15 years and MDR-TB in southern African countries with high HIV prevalence.

Surveillance data from 35 countries suggest that proportions of MDR-TB in children are not lower than those in adultshttp://ow.ly/kPgPH

Description of pediatric tuberculosis evaluated in a referral center in istanbul Turkey

PURPOSE

Diagnosis of tuberculosis (TB) in children is more challenging than in adults. This study aimed to describe demographical, clinical and laboratory findings of children diagnosed with tuberculosis in Turkey, including the issues of contact tracing, culture positivity and forms of the disease.

MATERIALS AND METHODS

Clinical and laboratory data of 51 children with a mean age of 8.0±4.6 years who were diagnosed with TB were retrospectively reviewed. Main diagnostic tools included tuberculin skin test, chest X-ray, sputum/gastric aspirate culture with sensitivity testing, and direct microscopy for acid-fast bacilli on available samples. Clinical characteristics and outcomes of the patients were examined.

RESULTS

Thirty-six (70.6%) children were diagnosed with intra-thoracic and 15 (29.4%) with extra-thoracic tuberculosis. Twenty-eight of the patients had a positive Bacillus Calmette-Guérin vaccine scar (28/51, 54.9%) and 23/51 (45.1%) had a positive tuberculin skin test. An adult TB contact was identified in 27 (52.9%) of the cases. On direct microscopy, acid-fast bacilli were found in nine (17.6%) patients and positive culture for Mycobacterium tuberculosis was found in 19 (37.3%). Drug resistance to isoniazid was detected in four (7.8%). One patient with nephrotic syndrome and miliary tuberculosis died during follow-up. All other patients responded well to the treatment.

CONCLUSION

Focusing on active contact tracing among all household contacts of tuberculous cases may be helpful in early identification and controlling childhood disease, even in regions with low disease prevalence. Adopting a suspicious and proactive approach in this particular age group is warranted.

Evaluation of new strategies for the diagnosis of tuberculosis among pediatric contacts of tuberculosis patients

BACKGROUND

In young children, underdiagnosis and diagnostic delay have an adverse effect on morbidity and mortality of tuberculosis (TB). This study evaluated new strategies for early TB diagnosis using an outpatient protocol in children between 0 and 5 years of age, with a recent household TB contact.

METHODS

Case recruitment was performed in Manaus, Amazonas, Brazil, from 2008 to 2009. Epidemiologic and clinical data, tuberculin test, chest radiograph and 2 induced sputum respiratory samples from each participant were obtained. Laboratory diagnosis was based on Lowenstein-Jensen (LJ) culture, mycobacteria growth indicator tube (MGIT) and polymerase chain reaction. We conducted a study of comparison of diagnostic tests and a study of cases and controls to identify the clinical characteristics of the population with positive culture and polymerase chain reaction results.

RESULTS

A total of 102 children were evaluated. Thirty-two fulfilled criteria of suspicion of TB. MGIT was more sensitive (P = 0.035) and faster (P < 0.001) than LJ. Clinical score, MGIT, LJ and polymerase chain reaction presented no concordance or slight concordance. A positive MGIT culture was only associated with a strong tuberculin test reaction (P = 0.026). The combination of MGIT with the clinical score allowed the diagnosis of 33% more cases with little or no symptomatology compared with the exclusive use of the clinical classification.

CONCLUSIONS

The sensitivity and speed of MGIT demonstrate the utility of liquid cultures for the diagnosis in children. Furthermore, these results suggest that the use of MGIT in children presenting recent household TB contact and a strong tuberculin test reaction may be a strategy to improve early TB diagnosis.

Helminths and skewed cytokine profiles increase tuberculin skin test positivity in Warao Amerindians

The immune regulatory mechanisms involved in the acquisition of Mycobacterium tuberculosis infection in children are largely unknown. We investigated the influence of parasitic infections, malnutrition and plasma cytokine profiles on tuberculin skin test (TST) positivity in Warao Amerindians in Venezuela. Pediatric household contacts of sputum smear-positive tuberculosis (TB) cases were enrolled for TST, chest radiograph, plasma cytokine analyses, QuantiFERON-TB Gold In-Tube (QFT-GIT) testing and stool examinations. Factors associated with TST positivity were studied using generalized estimation equations logistic regression models. Of the 141 asymptomatic contacts, 39% was TST-positive. After adjusting for age, gender and nutritional status, TST positivity was associated with Trichuris trichiura infections (OR 3.5, 95% CI 1.1-11.6) and low circulating levels of T helper 1 (Th1) cytokines (OR 0.51, 95% CI 0.33-0.79). Ascaris lumbricoides infections in interaction with Th2- and interleukin (IL)-10-dominated cytokine profiles were positively associated with TST positivity (OR 3.1, 95% CI 1.1-8.9 and OR 2.4, 95% CI 1.04-5.7, respectively). A negative correlation of QFT-GIT mitogen responses with Th1 and Th2 levels and a positive correlation with age were observed (all p < 0.01). We conclude that helminth infections and low Th1 cytokine plasma levels are significantly associated with TST positivity in indigenous Venezuelan pediatric TB contacts.

Non-invasive diagnosis of lung tuberculosis in children by single voxel ¹H-magnetic resonance spectroscopy

Our previous study showed that (1)H-magnetic resonance spectroscopy ((1)H-MRS) can detect lipid peaks characteristic for Mycobacterium tuberculosis infection in cerebral lesions of young children; therefore, we aimed to extend and validate the application of (1)H-MRS for the diagnosis of active pulmonary tuberculosis lesions in three adolescent patients. Here, we document lipid peaks characteristic for M. tuberculosis infection by (1)H-MRS from lung tissue surrounding lung cavities of two patients whose sputum samples were positive for acid-fast bacilli by microscopy and positive for M. tuberculosis by genetic testing, indicating active tuberculosis. A similar lipid peak was found also in the pleural effusion of a third patient with concurrent lung cavity compatible with active tuberculosis. However, in a patient with a pyogenic pulmonary abscess, (1)H-MRS of the drained pus displayed different characteristic peaks but no lipid peak at all.

CONCLUSION

Our findings further validate (1)H-MRS as a rapid, non-invasive, and specific diagnostic tool for active tuberculosis in children with microbiologically documented infection outside the central nervous system, specifically in the lungs.

QuantiFERON®-TB gold in-tube performance for diagnosing active tuberculosis in children and adults in a high burden setting

AIM

To determine whether QuantiFERON®-TB Gold In-Tube (QFT) can contribute to the diagnosis of active tuberculosis (TB) in children in a high-burden setting and to assess the performance of QFT and tuberculin skin test (TST) in a prospective cohort of TB suspect children compared to adults with confirmed TB in Tanzania.

METHODS

Sensitivity and specificity of QFT and TST for diagnosing active TB as well as indeterminate QFT rates and IFN-γ levels were assessed in 211 TB suspect children in a Tanzanian district hospital and contrasted in 90 adults with confirmed pulmonary TB.

RESULTS

Sensitivity of QFT and TST in children with confirmed TB was 19% (5/27) and 6% (2/31) respectively. In adults sensitivity of QFT and TST was 84% (73/87) and 85% (63/74). The QFT indeterminate rate in children and adults was 27% and 3%. Median levels of IFN-γ were lower in children than adults, particularly children <2 years and HIV infected. An indeterminate result was associated with age <2 years but not malnutrition or HIV status. Overall childhood mortality was 19% and associated with an indeterminate QFT result at baseline.

CONCLUSION

QFT and TST showed poor performance and a surprisingly low sensitivity in children. In contrast the performance in Tanzanian adults was good and comparable to performance in high-income countries. Indeterminate results in children were associated with young age and increased mortality. Neither test can be recommended for diagnosing active TB in children with immature or impaired immunity in a high-burden setting.