Recent advances in the diagnosis of childhood tuberculosis

Evaluation of radiological capacity and usage in paediatric TB diagnosis: A mixed-method protocol of a comparative study in Mozambique, South Africa and Spain

INTRODUCTION

Tuberculosis remains one of the top ten causes of mortality globally. Children accounted for 12% of all TB cases and 18% of all TB deaths in 2022. Paediatric TB is difficult to diagnose with conventional laboratory tests, and chest radiographs remain crucial. However, in low-and middle-income countries with high TB burden, the capacity for radiological diagnosis of paediatric TB is rarely documented and data on the associated radiation exposure limited.

METHODS

A multicentre, mixed-methods study is proposed in three countries, Mozambique, South Africa and Spain. At the national level, official registry databases will be utilised to retrospectively compile an inventory of licensed imaging resources (mainly X-ray and Computed Tomography (CT) scan equipment) for the year 2021. At the selected health facility level, three descriptive cross-sectional standardised surveys will be conducted to assess radiology capacity, radiological imaging diagnostic use for paediatric TB diagnosis, and radiation protection optimization: a site survey, a clinician-targeted survey, and a radiology staff-targeted survey, respectively. At the patient level, potential dose optimisation will be assessed for children under 16 years of age who were diagnosed and treated for TB in selected sites in each country. For this component, a retrospective analysis of dosimetry will be performed on TB and radiology data routinely collected at the respective sites. National inventory data will be presented as the number of units per million people by modality, region and country. Descriptive analyses will be conducted on survey data, including the demographic, clinical and programmatic characteristics of children treated for TB who had imaging examinations (chest X-ray (CXR) and/or CT scan). Dose exposure analysis will be performed by children's age, gender and disease spectrum.

DISCUSSION

As far as we know, this is the first multicentre and multi-national study to compare radiological capacity, radiation protection optimization and practices between high and low TB burden settings in the context of childhood TB management. The planned comparative analyses will inform policy-makers of existing radiological capacity and deficiencies, allowing better resource prioritisation. It will inform clinicians and radiologists on best practices and means to optimise the use of radiological technology in paediatric TB management.

Diagnostic accuracy of Xpert MTB/RIF Ultra for childhood tuberculosis in West Africa - a multicenter pragmatic study

OBJECTIVE

To evaluate the performance of Xpert Mycobacterium Tuberculosis/rifampicin (MTB/RIF) Ultra (Ultra) for diagnosis of childhood tuberculosis (TB) within public health systems.

METHODS

In this cross-sectional study, children aged <15 years with presumptive pulmonary TB were consecutively recruited and evaluated for TB at tertiary-level hospitals in Benin, Mali, and Ghana. Bivariate random-effects models were used to determine the pooled sensitivity and specificity of Ultra against culture. We also estimated its diagnostic yield against a composite microbiological reference standard (cMRS) of positive culture or Ultra.

RESULTS

Overall, 193 children were included in the analyses with a median (interquartile range) age of 4.0 (1.1-9.2) years, 88 (45.6%) were female, and 36 (18.7%) were HIV-positive. Thirty-one (16.1%) children had confirmed TB, 39 (20.2%) had unconfirmed TB, and 123 (63.7%) had unlikely TB. The pooled sensitivity and specificity of Ultra verified by culture were 55.0% (95% confidence interval [CI]: 28.0-79.0%) and 95.0% (95% CI: 88.0-98.0%), respectively. Against the cMRS, the diagnostic yield of Ultra and culture were 67.7% (95% CI: 48.6-83.3%) and 70.9% (95% CI: 51.9-85.8%), respectively.

CONCLUSION

Ultra has suboptimal sensitivity in children with TB that were investigated under routine conditions in tertiary-level hospitals in three West African countries.

QuantiFERON Gold-In-Tube for the diagnosis of mycobacterial tuberculosis infection in children under 5 years of age: A systematic review and meta-analysis

BACKGROUND

Previous meta-analysis regarding the performance of QuantiFERON Gold-In-Tube in children have yielded contrasting results. Emerging data in children younger than 5 years of age necessitates a new analysis.

METHODS

Systematic searches were conducted of MedLINE, EMBASE and Cochrane databases between 1998-2023. Pooled estimates of sensitivities and specificities of QFT-GIT compared to tuberculin skin test (TST) were calculated. The Kappa (k) coefficient was calculated for each study to determine the degree of congruence between TST and QFT-GIT results. Studies including patients co-infected with HIV or other immune compromising conditions or those treated with anti-tubercular treatment were excluded.

RESULTS

Seventeen studies (4335 patients) were included in quantitative analysis. All studies were conducted in middle to high income countries. They were conducted across 14 countries and 4 studies in countries with high TB incidence. The pooled sensitivity, specificity and DOR were 0.45 (0.42-0.48), 0.96 (0.96-0.97) and 18.84 (7.33-48.41) respectively. The ability of QFT-GIT to discriminate with disease and no disease was "good" as demonstrated by a summary receiver operating characteristic curve with area under curve of 0.7812. The average Kappa (k) co-efficient was 0.501 with a wide variety of values between studies (0.167 to 0.800).

CONCLUSION

The findings of this meta-analysis support the judicious use of QFT-GIT in children 5 years and under, with caution as a sole test to exclude Tuberculosis in this age group. The heterogeneity and methodological quality of diagnostic studies limits the generalisability of results.

Comparison of chest radiograph findings in ambulatory and hospitalized children with pulmonary tuberculosis

BACKGROUND

The diagnosis of childhood tuberculosis (TB) is, in many instances, solely reliant on chest radiographs (CXRs), as they are often the only diagnostic tool available, especially in TB-endemic areas. Accuracy and reliability of CXRs for detecting TB lymphadenopathy may vary between groups depending on severity of presentation and presence of parenchymal disease, which may obscure visualization.

OBJECTIVE

To compare CXR findings in ambulatory versus hospitalized children with laboratory confirmed pulmonary TB versus other lower respiratory tract infections (LRTI) and test inter-rater agreement for these findings.

MATERIALS AND METHODS

Retrospective review, by two pediatric radiologists, of CXRs performed on children < 12 years old referred for evaluation of LRTI with clinical suspicion of pulmonary TB in inpatient and outpatient settings. Each radiologist commented on imaging findings of parenchymal changes, lymphadenopathy, airway compression and pleural effusion. Frequency of imaging findings was compared between patients based on location and diagnosis and inter-rater agreement was determined. Accuracy of radiographic diagnosis was compared to laboratory testing which served as the gold standard.

RESULTS

The number of enrolled patients was 181 (54% males); 69 (38%) were ambulatory and 112 (62%) were hospitalized. Of those enrolled, 87 (48%) were confirmed to have pulmonary TB, while 94 (52%) were other LRTI controls. Lymphadenopathy and airway compression were more common in TB patients than other LRTI controls, regardless of patient location. Parenchymal changes and pleural effusion were more common in hospitalized than ambulatory patients, regardless of patient diagnosis. Agreement for parenchymal changes was higher in the hospitalized group (kappa [κ] = 0.75), while agreement for lymphadenopathy (κ = 0.65) and airway compression (κ = 0.68) was higher in the ambulatory group. The specificity of CXRs for TB diagnosis (> 75%) was higher than the sensitivity (< 50%) for both ambulatory and hospitalized groups.

CONCLUSION

Higher frequency of parenchymal changes among hospitalized children may conceal specific imaging findings of TB such as lymphadenopathy, contributing to the poor reliability of CXRs. Despite this, the high specificity of CXRs shown in our results is encouraging for continued use of radiographs for TB diagnosis in both settings.

Diagnostic accuracy of urine based lipoarabinomannan point of care tuberculosis diagnostic test in HIV negative children: a systematic review and meta-analysis

Tuberculosis is predicted to be a major undocumented cause of mortality in children. This systematic review with meta-analysis assessed the diagnostic accuracy of Lipoarabinomannan antigen testing (FujiLAM) in urine in HIV-negative children with TB-like signs and symptoms. PubMed, EMBASE, Scopus, Cochrane database and Google Scholar search engine were searched to identify relevant studies from earliest records to June 2022 without any language restriction. Three studies were finalized, patients were recruited from Africa and Haiti. Among microbiologically confirmed pediatric TB patients, pooled sensitivity and specificity of FujiLAM (with 95% CI) was 52% (35%-69%) and 90% (85%-93%) respectively. In both clinical (unconfirmed) and microbiological confirmed TB cases, sensitivity reduced to 24% (16%-34%) while specificity was 91%(80%-97%). We concluded that due to ease in obtaining urine sample, FujiLAM can be used as point-of-care TB test in HIV negative children, however more data from different population is needed.

The Interferon-Gamma Release Assay versus the Tuberculin Skin Test in the Diagnosis of Mycobacterium tuberculosis Infection in BCG-Vaccinated Children and Adolescents Exposed or Not Exposed to Contagious TB

BACKGROUND

Children have an increased risk of developing active tuberculosis (TB) after exposure to Mycobacterium tuberculosis (M.tb), and they are more likely to develop the most severe forms of TB. Rapid diagnosis and treatment of latent M.tb infection (LTBI) is essential to lessen the devastating consequences of TB in children.

OBJECTIVE

The aim of the study was to evaluate TST (tuberculin skin test) and IGRA (interferon-gamma release assay) utility in identifying LTBI in a cohort of Bacille Calmette-Guérin (BCG)-vaccinated Polish children and adolescents exposed or not exposed to contagious TB. In addition, we asked whether quantitative assessment of IGRA results could be valuable in predicting active TB disease.

RESULTS

Of the 235 recruited volunteers, 89 (38%) were TST-positive (TST+), 74 (32%) were IGRA-positive (IGRA+), and 62 (26%) were both TST+ and IGRA+. The frequency of TST positivity was significantly higher in the group with (59%) than without TB contact (18%). The percentage of TST+ subjects increased with age from 36% in the youngest children (<2 years) to 47% in the oldest group (>10 years). All positive IGRA results were found solely in the group of children with TB contact. There was a significant increase in the rate of positive IGRA results with age, from 9% in the youngest to 48% in the oldest group. The 10 mm TST cutoff showed good sensitivity and specificity in both TB exposed and nonexposed children and was associated with excellent negative predictive value, especially among nonexposed volunteers. Mean IFN-γ concentrations in IGRA cultures were significantly higher in the group of LTBI compared to the children with active TB disease, both TST+ and TST-.

CONCLUSIONS

Both TST and IGRA can be used as screening tests for BCG-vaccinated children and adolescents exposed to contagious TB.

Review of Pediatric Tuberculosis in the Aftermath of COVID-19

In 2014, the World Health Organization developed the End Tuberculosis Strategy with the goal of a 95% reduction in deaths from tuberculosis (TB) by 2035. The start of the COVID-19 pandemic and global lockdown has had a major impact on TB awareness, screening, diagnosis, and prompt initiation of treatment, inevitably leading to a significant setback. We explore pediatric tuberculosis through the lens of the COVID-19 era, investigating how COVID-19 has impacted pediatric TB cases in different regions of the world and what the implications are for management moving forward to mitigate these effects. Furthermore, in light of recent findings showing how exposed infants and children are at higher risk than we thought of contracting the disease, greater attention and resources are needed to prevent further downward trends.

End-point definition and trial design to advance tuberculosis vaccine development

Tuberculosis (TB) remains a leading infectious cause of death worldwide and the coronavirus disease 2019 pandemic has negatively impacted the global TB burden of disease indicators. If the targets of TB mortality and incidence reduction set by the international community are to be met, new more effective adult and adolescent TB vaccines are urgently needed. There are several new vaccine candidates at different stages of clinical development. Given the limited funding for vaccine development, it is crucial that trial designs are as efficient as possible. Prevention of infection (POI) approaches offer an attractive opportunity to accelerate new candidate vaccines to advance into large and expensive prevention of disease (POD) efficacy trials. However, POI approaches are limited by imperfect current tools to measure Mycobacterium tuberculosis infection end-points. POD trials need to carefully consider the type and number of microbiological tests that define TB disease and, if efficacy against subclinical (asymptomatic) TB disease is to be tested, POD trials need to explore how best to define and measure this form of TB. Prevention of recurrence trials are an alternative approach to generate proof of concept for efficacy, but optimal timing of vaccination relative to treatment must still be explored. Novel and efficient approaches to efficacy trial design, in addition to an increasing number of candidates entering phase 2-3 trials, would accelerate the long-standing quest for a new TB vaccine.

Integration of systematic screening for tuberculosis in outpatient departments of urban primary healthcare facilities in Zambia: a case study of Kitwe district

Background

Tuberculosis (TB) is the leading cause of death from a single infectious agent globally, killing about 1.5 million people annually, yet 3 million cases are missed every year. The World Health Organization recommends systematic screening of suspected active TB patients among those visiting the healthcare facilities. While many countries have scaled-up systematic screening of TB, there has been limited assessment of the extent of its integration into the health system. This study sought to explore factors that shape the integration of systematic screening of TB in outpatient departments of primary healthcare facilities in Kitwe district, Zambia.

Methods

This was a qualitative case study with health providers including district managers, TB focal point persons and laboratory personnel working in six purposively selected primary healthcare facilities. Data was collected through key informant (n = 8) and in-depth (n = 15) interviews. Data analysis was conducted using QDA Miner software and guided by Atun’s Integration framework.

Results

The facilitators to integration of systematic screening for TB into out patient departments of primary health facilities included the perceived high burden TB, compatibility of the systematic screening for TB program with healthcare workers training and working schedules, stakeholder knowledge of each others interest and values, regular performance management and integrated outreach of TB screening services. Constraining factors to integration of systematic screening for TB into outpatient departments included complexity of screening for TB in children, unbalanced incentivization mechanisms, ownership and legitimacy of the TB screening program, negative health worker attitudes, social cultural misconceptions of TB and societal stigma as well as the COVID-19 pandemic.

Conclusion

Systematic screening of TB is not fully integrated into the primary healthcare facilities in Zambia to capture all those suspected with active TB that make contact with the health system. Finding the missing TB cases will, therefore, require contextual adaptation of the systematic screening for TB program to local needs and capacities as well as strengthening the health system.

Accuracy and agreement of the Tuberculin Skin Test (TST) and the QuantiFERON-TB Gold In-tube test (QFT) in the diagnosis of tuberculosis in Indian children

PURPOSE

Accurate diagnosis of TB in children is hampered by poor specificity of symptoms in endemic countries and the paucibacillary nature of childhood TB. This study was done to compare the accuracy and agreement of the tuberculin skin test (TST) and the QuantiFERON-TB Gold In-tube test (QFT) in diagnosing tuberculosis (TB) in a predominantly BCG-vaccinated population of children.

METHODS

This retrospective cohort study enrolled all children aged 1-15 years who underwent TST and QFT testing as part of screening for TB. Children were classified according to the 2014 WHO case definition of TB, and statistical analysis was done to generate data on concordance between the TST and the QFT as well as sensitivity and specificity within WHO-defined groups.

RESULTS

TST and QFT concordance was 83.9% overall (kappa 0.51), 79% in those with WHO-defined TB and 89% in those without TB. TST+/QFT-discordance was commoner than QFT+/TST- discordance across groups. The sensitivity of the TST vs. the QFT was 70.8% vs. 50% for WHO-defined TB, with comparable specificity at 89% vs. 90% respectively.

CONCLUSIONS

The higher sensitivity of the cheaper and simpler TST supports its use for TB diagnosis in a normally nourished population of BCG-vaccinated children.

Tuberculosis/HIV Prevalence and Treatment Success among Children Receiving Care in Two Tertiary Health Facilities within Ogun State, Nigeria

Background

About 1 million children become ill with tuberculosis every year, representing 10-12% of all cases of tuberculosis notified globally. HIV infection in children is often due to transmission from mothers to children. HIV infection in children increases their risk of having tuberculosis. Sub-Sahara Africa has one of the highest TB incidences and HIV prevalence thus children in this region bear a huge burden of TB/HIV infection. In addition, the treatment success rate in many countries is rarely disaggregated to evaluate children. Thus, this study aims to determine the prevalence of TB/HIV coinfection and treatment success among children with tuberculosis attending clinics in two tertiary institutions in Ogun State, Nigeria.

Methodology

The study was a retrospective cohort study of routine programme data of all children diagnosed and treated for tuberculosis from January 2015 to June 2017 in two tertiary hospitals in OgunState, Nigeria. The hospitals were Olabisi Onabanjo University Teaching Hospital Sagamu and Federal Medical Centre Abeokuta, Ogun State. Data were retrieved from the facility TB register and analyzed using epi info.

Results

A total of 759 patients were registered for treatment at the two tertiary facilities between January 2015 and June 2017. Of these, 112(14.8%) were children 0-14 years of age. Most of the children (95.54%) had pulmonary tuberculosis. Treatment success was 81.3%. About half (46.4%) of the patients were HIV positive. Age, site of disease, bacteriological diagnosis, and weight at the commencement of treatment were significantly associated with HIV status while none of the socio-demographic variables were associated with treatment outcome.

Conclusion

There is a need to look for ways to further improve the current treatment success rate of children with tuberculosis. There should be increased efforts also to find better ways of diagnosing childhood tuberculosis. The high HIV rate among children with TB is of concern and strategies should be put in place to prevent HIV transmission to children.

Rapid detection of Mycobacterium tuberculosis in children using blood and urine specimens

INTRODUCTION

Laboratory and clinical features of childhood tuberculosis (TB) are non-specific and establishing an accurate diagnosis remains a challenge. This study evaluated a Single tube nested-PCR (STNPCR) to detect genomic DNA of Mycobacterium tuberculosis complex in blood and urine.

METHODS

Biological samples were obtained from children (<15 years old) with clinical suspicion of pulmonary and extrapulmonary TB at public hospitals in Recife-Pernambuco, Brazil. Cultures yielded negative results in a majority of childhood TB cases, which are generally paucibacillary. A set of clinical, epidemiological, radiological, and laboratory criteria with evident clinical improvement after anti-TB treatment were frequently used to define childhood TB cases.

RESULTS

Ninety children with clinical suspicion were enrolled in this study (44 with TB and 46 without TB). The pulmonary TB group had 20 confirmed cases and 46 negative controls, while the extrapulmonary TB group had 24 confirmed cases. The STNPCR showed sensitivities to pulmonary and extrapulmonary TB of 47.4% and 52.2% (blood) and 38.8% and 20% (urine), respectively. Considering the low performance of STNPCR on separate samples, we decided to perform a combined analysis (parallel sensitivity analysis) of the results from blood and urine samples. The parallel sensitivity increased to 65% in blood and 62.5% in urine. The specificity in both samples ranged from 93.5-97.8%.

CONCLUSIONS

Although STNPCR showed moderate sensitivity, the specificity is high; therefore, the test can be used as an auxiliary tool to diagnose TB in children. It is a rapid test that demonstrated better performance than other diagnostic tests in paucibacillary samples as it does in childhood tuberculosis.

Recurrent Tuberculosis in a Young Child

A young child, 19 months of age, presented with a second episode of tuberculosis after full recovery from initial tuberculosis disease 6 months earlier. Mycobacterium tuberculosis strains isolated from both episodes were genotyped and differed from one another. We present the first case of proven tuberculosis reinfection in a likely immunocompetent child, living in a high-risk environment favorable for exposition to M. tuberculosis but in a low-incidence country.

A three-marker protein biosignature distinguishes tuberculosis from other respiratory diseases in Gambian children

Background

Our study aimed to identify a host cytokine biosignature that could distinguish childhood tuberculosis (TB) from other respiratory diseases (OD).

Methods

Cytokine responses in prospectively recruited children with symptoms suggestive of TB were measured in whole blood assay supernatants, harvested after overnight incubation, using a Luminex platform. We used logistic regression models with Least Absolute Shrinkage and Selection Operator (LASSO) penalty to identify the optimal biosignature associated with confirmed TB disease in the training set. We subsequently assessed its performance in the test set.

Findings

Of the 431 children included in the study, 44 had bacteriologically confirmed TB, 60 had clinically diagnosed TB while 327 had OD. All children were HIV-negative. Application of LASSO regression models to the training set (n = 260) resulted in the combination of IL-1ra, IL-7 and IP-10 from unstimulated samples as the optimally discriminant cytokine biosignature associated with bacteriologically confirmed TB. In the test set (n = 171), this biosignature distinguished children diagnosed with TB disease, irrespective of microbiological confirmation, from OD with area under the receiver operator characteristic curve (AUC) of 0•74 (95% CI: 0•67, 0•81), and demonstrated sensitivity and specificity of 72•2% (95% CI: 60•4, 82•1%) and 75•0% (95% CI: 64•9, 83•4%) respectively, with its performance independent of their age group and their age- and sex-adjusted nutritional status.

Interpretation

This novel biosignature of childhood TB derived from unstimulated supernatants is promising. Independent validation with further optimisation will improve its performance and translational potential.

Funding

Steinberg Fellowship (McGill University); Grand Challenges Canada; MRC Program Grant.

Diagnostic performance of culture filtered protein 10-specific perforin in pediatric patients with active tuberculosis

Background

Mycobacterium tuberculosis (Mtb)‐specific perforin were significantly increased in patients with tuberculosis. This study aims to evaluate the diagnosis value of Mtb‐specific perforin in pediatric patients with tuberculosis.

Methods

Diagnostic performance of perforin levels induced by 6‐kDa early secreted antigen target (ESAT6) or culture filtered protein 10 (CFP10) were evaluated in eighty‐six samples from children participants by receiver operating characteristic curve analysis. Flow cytometry was used to detect the expression of perforin and INF‐γ of CD4⁺, CD8⁺ T cells in response to CFP10 stimulation.

Results

After ex vivo stimulation, levels of ESAT6/CFP10‐specific perforin in LTBI patients were significantly higher than active TB (ATB) patients, non‐tuberculosis infection (non‐TB), and health control (HC) individuals. The diagnostic efficacy of CFP10‐specific perforin for TB diagnosis was significantly higher than ESAT6‐specific perforin and T‐SPOT assay, and when 0.74 ng/mL was taken as the cutoff value, the sensitivity, specificity, and accuracy were 97.83%, 87.5%, and 93.02%. CFP10‐specific perforin in both CD4⁺ and CD8⁺ T cells were significantly higher in ATB patients compared to HCs and further increased in LTBI patients. However, INF‐γ was mainly secreted by CD4⁺ T cells and showed no significant difference between LTBI and ATB patients. In addition, CFP10‐specific perforin can effectively distinguish between ATB and LTBI with the cutoff value of 1.80 ng/mL. Sensitivity and specificity were 88.46% and 85.62%, respectively.

Conclusions

CFP10‐specific perforin may be used as a novel cellular immunity‐based diagnostic marker of pediatric patients with tuberculosis, and with the potential for discriminating ATB from LTBI.

A transcriptional blood signature distinguishes early tuberculosis disease from latent tuberculosis infection and uninfected individuals in a Vietnamese cohort

OBJECTIVES

Global tuberculosis (TB) control is restricted by the failure to detect an estimated 3.3 million TB cases annually. In the majority of TB endemic settings, sputum smear microscopy is used to diagnose TB, but this test is insensitive for TB in its early stages. The objective of this study is to establish a concise gene signature that discriminates between individuals with early TB disease, latent TB infection (LTBI) and those without infection.

METHODS

This is a case control study nested within a cluster-randomised trial of population screening for active TB using Xpert MTB/RIF. Whole blood samples from 303 participants with active TB (97), LTBI (92) and uninfected individuals (114) were subject to transcriptomic analysis of selected target genes based on a systematic review of previous studies.

RESULTS

Analysis of 82 genes identified a pattern of differentially expressed genes in TB disease. A seven gene signature was identified that distinguished between TB disease and no TB disease with an AUC of 0.86 (95% CI: 0.80-0.91), and between TB disease from LTBI with an AUC of 0.88 (95% CI: 0.82-0.93).

CONCLUSION

This gene signature accurately distinguishes early TB disease from those without TB disease or infection, in the context of community-wide TB screening. It could be used as a non-sputum based screening tool or triage test to detect prevalent cases of TB in the community.

Pre-treatment loss to follow-up among children with multidrug-resistant tuberculosis in South Africa, 2008-2010

Multidrug-resistant (MDR) TB is more difficult to diagnose and treat compared with drug-susceptible TB. Young children are at greater risk of severe TB disease and death when treatment is delayed compared to adults. We sought to describe characteristics of children (<13 years) diagnosed with MDR TB between 2008-2010 in three South African provinces and assess factors associated with pre-treatment loss to follow-up. We matched laboratory and medical records at treatment facilities to identify pre-treatment loss and examined demographic and clinical characteristics for association with loss. Categorical variables were examined for association using Pearson's x2 or Fisher's exact test, employing Bonferroni correction for multiple pairwise comparisons. Between 2008-2010, 156 children were diagnosed with laboratory-confirmed MDR TB. Only 44% (n = 69) were documented as having received treatment. Young children (<2 years) (47/59, 80%), children with extrapulmonary (EP) TB (27/34, 79%), and children diagnosed at general hospitals (60/97, 62%) were most likely to be lost before treatment. Children most vulnerable to death from TB are most likely to be lost before treatment, possibly leading to underestimates of disease burden, case notifications, and poor outcomes among this population. Point-of-care diagnosis and robust follow-up may reduce pre-treatment loss in this population.

Tuberculosis in the paediatric population of Madrid in the last 26 years

INTRODUCTION

Tuberculosis (TB) continues to be a serious public health problem and establishing a definitive diagnosis among children is extremely challenging. Pulmonary tuberculosis is the most prevalent form, with children under the age of 2 years being at greatest risk of severe and disseminated forms. The aim of this study was to describe TB among children in Spain in recent years.

PATIENTS AND METHODS

A retrospective study of paediatric patients diagnosed with TB in two hospitals of the Community of Madrid over a 26-year period (1991-2017). Epidemiological and clinical variables, additional tests and treatments received were analysed.

RESULTS

170 children were included. The two most-affected age groups were infancy and adolescence. 42.9% of patients were immigrant children (South-America or Morocco). The main reasons for consultation were TB contact (20.6%) and fever (15.3%). At diagnosis, 61.8% of cases referred an epidemic environment, and 30.6% were asymptomatic. The Mantoux tuberculin skin test was positive in 92.2% of patients and IGRA was positive in 70.6%. Pulmonary TB was identified in 91.8% of children vs. 8.2% with extrapulmonary forms. Gastric juice culture was positive in 36.9% of cases and three strains resistant to isoniazid were isolated. All patients were cured without complications except one who died.

CONCLUSIONS

Pulmonary TB continues to be the most prevalent form among children and presumptive diagnosis (symptoms consistent with positive Mantoux test or suggestive X-ray) is the most common form of diagnosis. It is important to conduct a contact investigation in order to control the spread of TB.

Rapid Tuberculosis Diagnosis Using Reporter Enzyme Fluorescence

Tuberculosis is the most frequent cause of death in humans from a single infectious agent. Due to low numbers of bacteria present in sputum during early infection, diagnosis does not usually occur until >3 to 4 months after symptoms develop. We created a new more sensitive diagnostic that can be carried out in 10 min with no processing or technical expertise.

Tuberculosis is the most frequent cause of death in humans from a single infectious agent. Due to low numbers of bacteria present in sputum during early infection, diagnosis does not usually occur until >3 to 4 months after symptoms develop. We created a new more sensitive diagnostic that can be carried out in 10 min with no processing or technical expertise. This assay utilizes the Mycobacterium tuberculosis-specific biomarker BlaC in reporter enzyme fluorescence (REF) that has been optimized for clinical samples, designated REFtb, along with a more specific fluorogenic substrate, CDG-3. We report the first evaluation of clinical specimens with REFtb assays in comparison to the gold standards for tuberculosis diagnosis, culture and smear microscopy. REFtb assays allowed diagnosis of 160 patients from 16 different countries with a sensitivity of 89% for smear-positive, culture-positive samples and 88% for smear-negative, culture-positive samples with a specificity of 82%. The negative predictive value of REFtb for tuberculosis infection is 93%, and the positive predictive value is 79%. Overall, these data point toward the need for larger accuracy studies by third parties using a commercially available REFtb kit to determine whether incorporation of REFtb into the clinical toolbox for suspected tuberculosis patients would improve case identification. If results similar to our own can be obtained by all diagnostic laboratories, REFtb would allow proper treatment of more than 85% of patients that would be missed during their initial visit to a clinic using current diagnostic strategies, reducing the potential for further spread of disease.

Causes of Pediatric Meningitis in Botswana: Results From a 16-Year National Meningitis Audit

BACKGROUND

Central nervous system infections are an important cause of childhood morbidity and mortality in high HIV-prevalence settings of Africa. We evaluated the epidemiology of pediatric meningitis in Botswana during the rollout of antiretroviral therapy, pneumococcal conjugate vaccine and Haemophilus influenzae type B (HiB) vaccine.

METHODS

We performed a cross-sectional study of children (<15 years old) evaluated for meningitis by cerebrospinal fluid (CSF) examination from 2000 to 2015, with complete national records for 2013-2014. Clinical and laboratory characteristics of microbiologically confirmed and culture-negative meningitis were described and incidence of Streptococcus pneumoniae, H. influenzae and cryptococcal meningitis was estimated for 2013-2014.

RESULTS

A total of 6796 unique cases were identified. Median age was 1 year [interquartile range 0-3]; 10.4% (435/4186) of children with available HIV-related records were known HIV-infected. Overall, 30.4% (2067/6796) had abnormal CSF findings (positive microbiologic testing or CSF pleocytosis). Ten percent (651/6796) had a confirmed microbiologic diagnosis; including 26.9% (175/651) Cryptococcus, 18.9% (123/651) S. pneumoniae, 20.3% (132/651) H. influenzae and 1.1% (7/651) Mycobacterium tuberculosis. During 2013-2014, national cryptococcal meningitis incidence was 1.3 cases per 100,000 person-years (95% confidence interval, 0.8-2.1) and pneumococcal meningitis incidence 0.7 per 100,000 person-years (95% confidence interval, 0.3-1.3), with no HiB meningitis diagnosed.

CONCLUSIONS

Following HiB vaccination, a marked decline in microbiologically confirmed cases of H. influenzae meningitis occurred. Cryptococcal meningitis remains the most common confirmed etiology, demonstrating gaps in prevention-of-mother-to-child transmission and early HIV diagnosis. The high proportion of abnormal CSF samples with no microbiologic diagnosis highlights limitation in available diagnostics.

Review on antibacterial activity of Himalayan medicinal plants traditionally used to treat pneumonia and tuberculosis

Objectives

The main objective of this review was to collect scattered literature on ethnomedicinal plants used to treat pneumonia and tuberculosis in the Himalayan region and their in-vitro validation against bacterial pathogens.

Key findings

Current review contains information on ethnomedicines of total 137 plants from Himalaya region. Out of these, 59 plants have been studied in vitro against bacteria while seven plants extracts have been checked for their toxicological effects. The most commonly used plant families for pneumonia and tuberculosis therapy in the study region were Asteraceae, Bignoniaceae and Fabaceae (seven plants in each); of these, Curcuma longa L., Punica granatum L. and Justicia adhatoda L. carried the most inhibiting potential against Staphylococcus aureus and Streptococcus pneumoniae while that of Acalypha indica L. against Mycobacterium tuberculosis. Different compounds such as ascorbic acid, curcumin, vasicine, piperine, quercetin, myricetin and gallic acid being reportedly isolated from these plants possess antibacterial potential.

Summary

Himalayan region has variety of ethnomedicinal plants used against pneumonia and tuberculosis; however, studies on in-vivo activity, toxicology and mechanism of action are very limited. Hence, detailed investigation on these aspects needs to be carried out for the development of novel antibacterial drugs from the studied plant species.

Utility of QuantiFERON®-TB gold In-Tube test compared with tuberculin skin test in diagnosing tuberculosis in Indian children with malnutrition

This prospective cohort study was conducted to compare the accuracy of QuantiFERON®-TB (QFT) Gold In-Tube test and tuberculin skin test (TST) in diagnosing tuberculosis (TB) in predominantly bacille Calmette-Guerin-vaccinated children with a high incidence of malnutrition. The sensitivity of the QFT versus the TST was 69.6% versus 52.9% for WHO-defined TB, with specificity of 86% versus 78.3%, respectively. The concordance of the TST and QFT was 79% overall (κ = 0.430), 62.5% in those with WHO-defined TB and 85.7% in those without TB. Majority of the QFT+/TST - discordance was seen in children with TB, whereas majority of the TST+/QFT - discordance was seen in those without TB. The TST was more likely to be negative in children with moderate-to-severe malnutrition (P = 0.003) compared to the QFT, which was more likely to be positive in younger children. The significantly better performance of the QFT in malnourished children and those at younger ages supports its use for TB diagnosis in these subpopulations.

Epidemiological characteristics of pulmonary tuberculosis among children in Shandong, China, 2005-2017

BACKGROUND

Diagnosis of tuberculosis (TB) in children is challenging. Epidemiological data of childhood pulmonary tuberculosis (PTB) are urgently needed.

METHODS

We described trends in epidemiology, clinical characteristics, and treatment outcomes in seven cities of Shandong province, China, during 2005-2017. Data were collected from the China Information System for Disease Control and Prevention.

RESULTS

Among 6283 (2.4% of all PTB) PTB cases aged < 18 years, 56.5% were male patients, 39.3% were smear-positive and 98.6% were new cases. The overall incidence of childhood PTB declined (7.62 to 3.74 per 100,000) during 2005-2017, with a non-significant change of annual percentage after 2010. While the incidence of smear-positive PTB (6.09 to 0.38 per 100,000 population) decreased significantly, but the incidence of smear-negative PTB (1.52 to 3.36 per 100,000 population) increased significantly during 2005-2017. The overall treatment success occurred among 94.2% childhood PTB. Ten children (0.2%) died.

CONCLUSION

The overall incidence of childhood PTB declined significantly with the disease burden shifting from smear-positive PTB to smear-negative PTB. The discrepancies between notifications and estimations in both TB morbidity and mortality of children need to be addressed urgently.

Comparison of IFN-γ Levels in Children with Tuberculosis Disease (TB) and Latent Tuberculosis Infection (LTBI)

AIM:

This study aimed to evaluate the importance of IFN-γ in the diagnosis of pediatric TB and LTBI and to compare the IFN-γ levels.

METHODS:

We analysed 100 patients examined for possible M. tuberculosis infection or disease at the Institute of Respiratory Diseases in Children, Kozle, Skopje. Patients were divided into 2 groups: TB disease and LTBI. The following parameters were analyzed: demographic characteristics, history of previous exposure to active TB, BCG vaccination and presence of BCG scar, lung X-ray findings, tuberculin skin test by the Monteux method and the value of INF-γ according to the Quantiferon TB gold test, direct samples of acid-alcohol-resistant bacilli of sputum and Löwenstein Jensen cultures. Informed parental consent was obtained for each child included in the study.

RESULTS:

In the LTBI group 60.9% had a scar from the vaccination while in the TB group 50% had BCG scar. TST induration diameters in children with or without BCG scar were significantly larger in patients with active TB. Children with active TB had significantly higher IFN-γ levels than children with LTBI. The IFN-γ for the cut-off of 0.35 IU/ml, has 64% sensitivity for detection of LTBI, versus 80.6% sensitivity for active disease. Children with close TB contact had significantly higher IFN-γ levels. Correlation between TST induration diameter and IFN-γ levels was stronger in the TB group.

CONCLUSION:

IFN-γ levels are significantly higher in children with active TB, and children with close contact with TB patient. It has better sensitivity in active TB. Using both tests (IFN-γ and TST) can improve the diagnose of LTBI and TB in countries where vaccination with BCG is widespread.

Combined use of Quantiferon and HBHA-based IGRA supports tuberculosis diagnosis and therapy management in children

OBJECTIVES

Interferon-γ release assays (IGRA) are designed for diagnosis of tuberculosis (TB) infection, and do not discriminate latent TB infection (LTBI) from active TB. Heparin-binding hemagglutinin antigen (HBHA) emerged as a promising antigen for TB diagnosis when used in IGRA format. Aim of this study was to prospectively evaluate the performance of an HBHA-based IGRA to support TB diagnosis and TB therapy monitoring in children with TB infection or active TB disease.

METHODS

Following clinical, microbiological and radiological assessment, children (0-14 years old) were tested by the QuantiFERON TB-Gold In tube (QFT) assay and an aliquot of whole-blood was stimulated with HBHA and IFNγ evaluated only in QFT-positive subjects.

RESULTS

Among the 550 children tested, 486 (88.4%) scored negative and 64 (11.6%) positive. None of the QFT-negative had active TB. Among the QFT-positive, 45 were with LTBI and 19 active TB. HBHA-IGRA scored positive in 41/45 children (91.1%) with LTBI and in 6/19 active TB children (31.6%) at diagnosis (p = 0.001); remarkably, 5 of these 6 children with active TB scoring HBHA-positive were asymptomatic. Moreover, following TB-specific therapy, most of the non-HBHA-responding children, gained an HBHA-positive response.

CONCLUSIONS

HBHA-based IGRA is a useful support in TB diagnosis and TB-therapy monitoring in children.

Biomarkers for diagnosis of childhood tuberculosis: A systematic review

Introduction

As studies of biomarkers of tuberculosis (TB) disease provide hope for a simple, point-of-care test, we aimed to synthesize evidence on biomarkers for diagnosis of TB in children and compare their accuracy to published target product profiles (TPP).

Methods

We conducted a systematic review of biomarkers for diagnosis of pulmonary TB in exclusively paediatric populations, defined as age less than 15 years. PubMed, EMBASE and Web of Science were searched for relevant publications from January 1, 2000 to November 27, 2017. Studies using mixed adult and paediatric populations or reporting biomarkers for extrapulmonary TB were excluded. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies—2 (QUADAS-2) framework. No meta-analysis was done because the published childhood TB biomarkers studies were mostly early stage studies and highly heterogeneous.

Results

The 29 studies included in this systematic review comprise 20 case-control studies, six cohort studies and three cross-sectional studies. These studies reported diverse and heterogeneous forms of biomarkers requiring different types of clinical specimen and laboratory assays. Majority of the studies (27/29 [93%]) either did not meet the criteria in at least one of the four domains of the QUADAS-2 reporting framework or the assessment was unclear. However, the diagnostic performance of biomarkers reported in 22 studies met one or both of the WHO-recommended minimal targets of 66% sensitivity and 98% specificity for a new diagnostic test for TB disease in children, and/or 90% sensitivity and 70% specificity for a triage test.

Conclusion

We found that majority of the biomarkers for diagnosis of TB in children are promising but will need further refining and optimization to improve their performances. As new data are emerging, stronger emphasis should be placed on improving the design, quality and general reporting of future studies investigating TB biomarkers in children.

Tuberculin skin test versus interferon-gamma release assay in refugee children: A retrospective cohort study

AIM

The aim of this study was to assist clinicians evaluating refugee children for latent tuberculosis infection (LTBI) by comparing paired tuberculin skin test (TST) and Quantiferon Gold In-Tube (QGIT) test results with clinical management decisions and follow-up data in a large cohort of newly arrived refugee children.

METHODS

This was a retrospective analysis of all refugee children (<15 years of age) evaluated for LTBI with both TST and interferon-γ release assay between 2007 and 2010 in the Illawarra-Shoalhaven region of New South Wales, Australia. Demographics, country of origin, bacille Calmette-Guerin (BCG) vaccination status, chest X-ray results, TST and QGIT test results, clinical management and outcome on long-term follow-up were assessed.

RESULTS

Of 272 children evaluated, complete results were available for 212 (78%). The vast majority (207; 98%) were from Africa or Southeast Asia. Overall, 33 (16%) children were treated for LTBI; 13 (39%) had concordant TST and QGIT results and 20 (61%) discordant results. Of 63 (30%) TST-positive (≥10 mm) children, 46 (73%) were QGIT assay-negative, 44 (70%) had a BCG scar, 3 (5%) were younger than 2 years and 6 (10%) were treated for LTBI. Of 32 QGIT assay-positive children, 15 (47%) were TST negative, 31 (97%) had a BCG scar, all were older than 2 years and 14 (44%) were treated for LTBI.

CONCLUSIONS

Discordant TST and QGIT results were found in a high percentage of refugee children. QGIT is convenient and more specific than TST to diagnose LTBI in BCG-vaccinated children, although a careful tuberculosis exposure history and clinical assessment to rule out active disease remain important.

Drug-Resistant Tuberculosis among Children, China, 2006-2015

Microbial drug resistance has become a major public health concern worldwide. To acquire epidemiologic data on drug-resistant tuberculosis (DR TB) among children, a major cause of illness and death for this population, we conducted a retrospective study of 2006–2015 data from 36 TB prevention and control institutions in Shandong Province, China. A total of 14,223 new TB cases, among which children (<18 years of age) accounted for only 5.5%, were caused by culture-confirmed Mycobacterium tuberculosis. Among children with TB, 18.9% had DR TB and 6.9% had multidrug-resistant TB. Over the past decade, the percentage of DR TB; multidrug-resistant TB; and overall first-line drug resistance for isoniazid, rifampin, ethambutol, and streptomycin among children increased significantly (at least 12%). Understanding the long-term trends of DR TB among children can shed light on the performance of TB control programs, thereby contributing to global TB control.

Accelerating access to quality TB care for pediatric TB cases through better diagnostic strategy in four major cities of India

Background

Diagnosis of TB in children is challenging, and is largely based on positive history of contact with a TB case, clinical and radiological findings, often without microbiological confirmation. Diagnostic efforts are also undermined by challenges in specimen collection and the limited availability of high sensitivity, rapid diagnostic tests that can be applied with a quick turnaround time. The current project was undertaken in four major cities of India to address TB diagnostic challenges in pediatric population, by offering free of cost Xpert testing to pediatric presumptive TB cases, thereby paving the way for better TB care.

Methods

A high throughput lab was established in each of the four project cities, and linked to various health care providers across the city through rapid specimen transportation and electronic reporting linkages. Free Xpert testing was offered to all pediatric (0–14 years) presumptive TB cases (both pulmonary and extra-pulmonary) seeking care at public and private health facilities.

Results

The current project enrolled 42,238 pediatric presumptive TB cases from April, 2014 to June, 2016. A total of 3,340 (7.91%, CI 7.65–8.17) bacteriologically confirmed TB cases were detected, of which 295 (8.83%, CI 7.9–9.86) were rifampicin-resistant. The level of rifampicin resistance in the project cohort was high. Overall Xpert yielded a high proportion of valid results and TB detection rates were more than three-fold higher than smear microscopy. The project provided same-day testing and early availability of results led to rapid treatment initiation and success rates and very low rates of treatment failure and loss to follow-up.

Conclusion

The current project demonstrated the feasibility of rolling out rapid and upfront Xpert testing for pediatric presumptive TB cases through a single Xpert lab per city in an efficient manner. Rapid turnaround testing time facilitated prompt and appropriate treatment initiation. These results suggest that the upfront Xpert assay is a promising solution to address TB diagnosis in children. The high levels of rifampicin resistance detected in presumptive pediatric TB patients tested under the project are a major cause of concern from a public health perspective which underscores the need to further prioritize upfront Xpert access to this vulnerable population.

The Incremental Value of Repeated Induced Sputum and Gastric Aspirate Samples for the Diagnosis of Pulmonary Tuberculosis in Young Children With Acute Community-Acquired Pneumonia

Background.

Mycobacterium tuberculosis (Mtb) contributes to the pathogenesis of childhood acute community-acquired pneumonia in settings with a high tuberculosis burden. The incremental value of a repeated induced sputum (IS) sample, compared with a single IS or gastric aspirate (GA) sample, is not well known.

Methods.

Two IS samples were obtained for Mtb culture from children enrolled as cases in the Pneumonia Etiology Research for Child Health (PERCH) study in South Africa. Nonstudy attending physicians requested GA if pulmonary tuberculosis was clinically suspected. We compared the Mtb yield of 2 IS samples to that of 1 IS sample and GA samples.

Results

. Twenty-seven (3.0%) culture-confirmed pulmonary tuberculosis cases were identified among 906 children investigated with IS and GA samples for Mtb. Results from 2 IS samples were available for 719 children (79.4%). Of 12 culture-confirmed pulmonary tuberculosis cases identified among children with ≥2 IS samples, 4 (33.3%) were negative at the first IS sample. In head-to-head comparisons among children with both GA and IS samples collected, the yield of 1 GA sample (8 of 427; 1.9%) was similar to that of 1 IS sample (5 of 427, 1.2%), and the yield of 2 GA samples (10 of 300; 3.3%) was similar to that of 2 IS samples (5 of 300; 1.7%). IS samples identified 8 (42.1%) of the 19 culture-confirmed pulmonary tuberculosis cases that were identified through submission of IS and GA samples.

Conclusions.

A single IS sample underestimated the presence of Mtb in children hospitalized with severe or very severe pneumonia. Detection of Mtb is enhanced by combining 2 IS with GA sample collections in young children with acute severe pneumonia.

TUBERCULOSIS IN PEDIATRIC PATIENTS: HOW HAS THE DIAGNOSIS BEEN MADE?

Objective:

To describe clinical, radiological, epidemiological, and microbiological characteristics of pediatric patients with diagnosis of tuberculosis in a period of 15 years.

Methods:

Retrospective study including children and adolescents younger than 18 years diagnosed with tuberculosis in the Clinical Hospital of the Universidade Estadual de Campinas in São Paulo State, Brazil. Active tuberculosis was defined by the identification of Mycobacterium tuberculosis in culture, microscopy, or histopathological examination. Children with positive clinical history and radiological tests who had been exposed to sick adults or with positive tuberculin skin test were also considered as having active tuberculosis. Statistical analysis compared the data obtained from children younger and older than 10 years of age, since they present a disease pattern more similar to adults.

Results:

There were 145 identified cases, 61.4% in patients under 10 years of age. The main symptoms reported were coughing (55.9%) and fever (46.9%), and the variables of fever, coughing, weight-loss, and pain were significantly influenced by age, with a higher frequency in older children. Diagnosis was confirmed by culture, microscopy, or histopathology in 67.6% of the cases. The other cases (32.4%) had the diagnosis of tuberculosis based on clinical, radiological, and epidemiological characteristics, as well as tuberculin skin test. The positivity for culture, microscopy, and tuberculin skin test was, respectively, 65.8, 35.7, and 72.3%. History of contact with a sick adult was confirmed in 37.2%, without influence of age.

Conclusions:

Diagnosis of tuberculosis in children is still a challenge, since all the confirmation tests have low positivity. These results demonstrate the need for new diagnostic methods and improved strategies for searching sick contacts.

Smear positivity in paediatric and adult tuberculosis: systematic review and meta-analysis

BACKGROUND

Tuberculosis (TB) diagnosis continues to rely on sputum smear microscopy in many settings. We conducted a meta-analysis to estimate the percentage of children and adults with tuberculosis that are sputum smear positive.

METHODS

We searched PubMed, MEDLINE, Embase, and Global Health databases for studies that included both children and adults with all forms of active TB. The pooled percentages of children and adults with smear positive TB were estimated using the inverse variance heterogeneity model. This review was registered in the PROSPERO database under registration number CRD42015015331.

RESULTS

We identified 20 studies meeting our inclusion criteria that reported smear positivity for a total of 18,316 children and 162,574 adults from 14 countries. The pooled percentage of paediatric TB cases that were sputum smear positive was 6.8 % (95 % Confidence Interval (CI) 2.2-12.2 %), compared with 52.0 % (95 % CI 40.0-64.0 %) among adult cases. Eight studies reported data separately for children aged 0-4 and 5-14. The percentage of children aged 0-4 that were smear positive was 0.5 % (95 % CI 0.0-1.9 %), compared with 14.0 % (95 % CI 8.9-19.4 %) among children aged 5-14.

CONCLUSIONS

Children, especially those aged 0-4, are much less likely to be sputum smear positive than adults. National TB programs relying on sputum smear for diagnosis are at risk of under-diagnosing and underestimating the burden of TB in children.

Treatment Outcomes of Childhood TB in Lagos, Nigeria

BACKGROUND

: Treatment outcomes of tuberculosis (TB) in children are rarely evaluated by most national TB programmes in sub-Saharan Africa. This study evaluated the treatment outcomes of children treated for TB in Lagos State, Nigeria.

METHODS

A retrospective review of programme data of the Lagos state TB and the Leprosy control programme in Nigeria from 1 January 2012 to 31 December 2012. Treatment outcomes were categorized according to the national TB guidelines.

RESULTS

A total of 535 cases of childhood TB were notified in 2012, representing 6.3% of the total TB cases notified in Lagos state in 2012. The prevalence of TB/HIV co-infection was 29%. The treatment success rate was 79.2% in TB/HIV-negative children compared with 73.4% in TB/HIV-positive children (p = 0.1268). Children <1 year had the worst treatment outcomes (p < 0.001).

CONCLUSION

There is a need to intensify effort at improving notification and treatment outcomes in children.

Epidemiology of drug-resistant tuberculosis among children and adolescents in South Africa, 2005-2010

OBJECTIVE

To describe the demographic and clinical characteristics of children and adolescents diagnosed with resistance to any anti-tuberculosis drug (drug-resistant tuberculosis; DR-TB) in South Africa.

DESIGN

We retrospectively reviewed medical records of all children (<13 years) and adolescents (13 to <18 years) with DR-TB at specialty hospitals in four South African provinces from 2005 to 2010.

RESULTS

During the review period, 774 children and adolescents (median age 11.3 years) were diagnosed with DR-TB at selected facilities. A high proportion of patients had a history of previous TB treatment (285/631; 45.2%), human immunodeficiency virus (HIV) infection (375/685; 54.7%), contact with a TB case (347/454; 76.4%), and smear-positive (443/729; 60.8%), cavitary (253/680, 38.7%) disease. Eighty-two per cent of patients with HIV infection received antiretroviral therapy. Of 626 patients diagnosed with multidrug-resistant TB (MDR-TB), 561 (89.6%) received a regimen consistent with national guidelines; the median length of treatment was 22 months (IQR 16-25). Among 400 patients with any DR-TB and a known outcome, 20.3% died during treatment.

CONCLUSION

Pediatric DR-TB in these provinces is characterized by complex clinical features at diagnosis, with one in five children dying during treatment. History of previous treatment and contact with a TB patient indicate opportunities for earlier diagnosis and treatment to improve outcomes.

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.

Newer Diagnostic Tests for Pulmonary Tuberculosis in Children

It has been well recognized that the diagnosis of pulmonary tuberculosis in children is often compromised by non-specific symptoms, paucibacillary nature of the disease, and the difficulty in collecting the specimen. Consequently, most tuberculosis cases in children are not confirmed, due to which the estimation of the global burden of tuberculosis in children may be inaccurate. There has also been a common misperception that diagnosis of tuberculosis and collecting respiratory specimen in children is always difficult. Because of this, microbiological confirmation of tuberculosis in young children is not routinely attempted in most endemic areas. With the emergence of HIV-related tuberculosis disease and drug-resistant tuberculosis, the availability of accurate, rapid and child friendly diagnostic tools to identify Mycobacterium tuberculosis in respiratory specimen are urgently required in endemic settings. There have been a large number of studies evaluating new diagnostic tests for tuberculosis in the past decade, but few have been evaluated in children. This review will address the developments in respiratory specimen collection and laboratory diagnostic tests of tuberculosis, with a focus on those that have been evaluated in children.

Recent advances in the diagnosis and treatment of childhood tuberculosis

Despite over 2.3 million (26% of global burden) cases of tuberculosis (TB) in India the accurate diagnosis of childhood TB remains a major challenge. Children with TB usually have paucibacillary disease and contribute little to disease transmission within the community. Consequently the treatment of children with TB is often not considered a priority by TB control programmes. Adequate and timely assessment of TB infection in childhood could diminish epidemiological burden as underdiagnosed pediatric patients can eventually evolve in to an active state and have the potential to disseminate the etiological agent Mycobacterium tuberculosis, notably increasing this worldwide public health problem. In this review we discuss the most important recent advances in the diagnosis of childhood TB: (1) Symptom-based approaches, (2) novel immune-based approaches, including in vitro interferon-γ IGRA release assays IGRA tests; and (3) bacteriological and molecular methods that are more rapid and/or less expensive than conventional culture techniques for TB diagnosis and/or drug-resistance testing. Recent advances have improved our ability to diagnose latent infection and active TB in children, nevertheless establishing a diagnosis of either latent infection or active disease in HIV-infected children remains a major challenge.

Performance of urine lipoarabinomannan assays for paediatric tuberculosis in Tanzania

We evaluated the diagnostic performance of two tests based on the release of lipoarabinomannan (LAM) into the urine, the MTB-LAM-ELISA assay and the Determine TB-LAM-strip assay, in children with suspected tuberculosis (TB) in a high TB/HIV-prevalence setting.In a prospective study, 132 children with suspected active TB were assigned to diagnostic subgroups. Urine samples were subjected to testing by both assays to ascertain sensitivity and specificity. Host factors associated with positive LAM results were investigated and LAM excretion monitored after antituberculous treatment initiation.18 (13.6%) children had culture-confirmed pulmonary TB. The assays' sensitivity was higher in HIV-positive versus HIV-negative children: 70% (95% confidence interval 35-93%) versus 13% (0-53%) for MTB-LAM-ELISA and 50% (19-81%) versus 0% (0-37%) for Determine TB-LAM. In 35 (27%) children with excluded active TB, both assays showed a specificity of 97.1% (85-100%). Proteinuria and low body mass index were independently associated with LAM positivity. In most patients, LAM excretion declined to zero during or at conclusion of antituberculous treatment.HIV/TB co-infected children might benefit from LAM-based tests to aid early TB diagnosis and subsequent positive impact on morbidity and mortality. Using LAM as a rule-in and treatment-monitoring tool may also show further potential.

Imaging of pediatric pathology during the Iraq and Afghanistan conflicts

United States Armed Forces radiologists deployed to Afghanistan and Iraq in modern military conflicts may encounter pediatric patients as a casualty of war or when providing humanitarian assistance to the indigenous population. Pediatric patients account for 4-7% of admissions at U.S. military hospitals during the Iraq and Afghanistan conflicts. It is pertinent for radiologists in the humanitarian care team to be familiar with imaging pediatric trauma patients, the pathology endemic to the local population, and delayed presentations of congenital and developmental disorders to adequately care for these patients. The radiological manifestations of various pediatric disorders seen in the setting of the Iraq and Afghanistan conflicts will be explored.

[Trends of tuberculosis in the Fifth Health Region, Buenos Aires Province, years 2000-2011]

The aim of this study was to describe the trends in tuberculosis (TB) in the Fifth Health Region (RSV) in the Buenos Aires Province. A trend study allowed the evaluation of the average variation of change in the incidence rate (IR) using simple linear regression expressed as a mean annual variation (VAP). The number of reported TB cases and IR per 100 000 population of all TB cases, pulmonary TB (PTB) and bacteriologically confirmed PTB from January 1, 2000 to December 31, 2011, were analyzed by age groups: 0-14; 15-29 and over 64 years of age. The decline in IR was less than 5% for all forms of TB and lower for bacteriologically confirmed PTB cases. The highest rate of PTB and IR was concentrated in the age group of 15-29 years with stable or slightly increasing trend of IR in bacteriologically confirmed PTB. There were similar trends for bacteriologically confirmed PTB in children. The fastest decline in PTB IR occurred in 0-14 age group, while for cases over 64 years of age the decline was sustained over time. TB continues to be a health risk in RSV, with cases in younger age groups. Therefore, it remains necessary to strengthen TB control activities in this region.

Differential in vivo expression of mycobacterial antigens in Mycobacterium tuberculosis infected lungs and lymph node tissues

Background

The clinical course of tuberculosis (TB) infection, bacterial load and the morphology of lesions vary between pulmonary and extrapulmonary TB. Antigens expressed in abundance during infection could represent relevant antigens in the development of diagnostic tools, but little is known about the in vivo expression of various M. tuberculosis antigens in different clinical manifestations. The aim of this study was to study the differences in the presence of major secreted as well as somatic mycobacterial antigens in host tissues during advanced rapidly progressing and fatal pulmonary disease with mainly pneumonic infiltrates and high bacterial load, and to compare this to the presence of the same antigens in TB lymphadenitis cases, which is mainly chronic and self-limiting disease with organised granulomas and lower bacterial load.

Methods

Human pulmonary (n = 3) and lymph node (n = 17) TB biopsies, and non-TB controls (n = 12) were studied. Ziehl-Neelsen stain, nested PCR 1S6110 and immunohistochemistry were performed. Major secreted (MPT32, MPT44, MPT46, MPT51, MPT53, MPT59, MPT63, and MPT64) and somatic mycobacterial antigens (Mce1A, Hsp65, and MPT57) were detected by using rabbit polyclonal antibodies.

Results

Plenty of bacilli were detectable with Ziehl-Neelsen stain in the lung biopsies while no bacilli were detected in the lymph node biopsies. All the cases were shown to be positive by PCR. Both secretory and somatic antigens were expressed in abundance in pulmonary infiltrates, while primarily somatic antigens were detected in the lymphadenitis cases. Of the secreted antigens, only MPT64 was consistently detected in both cases, indicating a preferential accumulation of this antigen within the inflammatory cells, even if the cells of the granuloma can efficiently restrict bacterial growth and clear away the secreted antigens.

Conclusions

This study shows that major secreted mycobacterial antigens were found in high amounts in advanced pulmonary lesions without proper granuloma formation, while their level of staining was very low, or absent, in the lymph node TB lesions with organised granulomas and very low bacillary load, with one exception of MPT64, suggesting its role in the persistence of chronic infection. These findings have implication for development of new diagnostic tools.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2334-14-535) contains supplementary material, which is available to authorized users.

Performance of interferon-γ release assay for the diagnosis of active or latent tuberculosis in children in the first 2 years of age: a multicenter study of the Italian Society of Pediatric Infectious Diseases

BACKGROUND

The diagnosis of latent or active tuberculosis in children is often challenging. Recently, interferon-γ release assays have been licensed, but their diagnostic accuracy in young children remains questionable as frequent false-negative or indeterminate results have been reported.

METHODS

We performed a multicenter, retrospective study in children 0-24 months of age who were tested at least once with QuantiFERON-TB Gold-in-tube (QTF-IT) ± tuberculin skin test (TST), to analyze its use and performance in clinical practice.

RESULTS

Eight-hundred and twenty-three children (449 males, median age 13.5 months) were enrolled. QTF-IT sensitivity and specificity for active tuberculosis were 92.4% and 98.6%, respectively. Indeterminate tests (4.2 %) were not related to age (P = 0.838) or gender (P = 0.223); 32 children (91.4 %) with an indeterminate QTF-IT ultimately resulted uninfected. In the 616 subjects with valid paired results of QTF-IT and TST, sensitivity and specificity were comparable (91.1% vs. 85.1% and 98.1% vs. 97.9%, respectively). Diagnostic concordance between tests was higher in Bacillus Calmétte-Guerin nonvaccinated children (κ = 0.802). A high rate of discordant tests was observed in latent infections.

CONCLUSIONS

QTF-IT showed good sensitivity and specificity, and a low rate of indeterminate results in the first 2 years of life, supporting its use at this age. However, considering costs and the similar performance between QTF-IT and TST, it is reasonable to suggest the latter as first-line testing in young children. The complementary use of TST and interferon-γ release assays may be considered in selected cases to improve the accuracy of testing.

Chest Radiographs for Pediatric TB Diagnosis: Interrater Agreement and Utility

The chest radiograph (CXR) is considered a key diagnostic tool for pediatric tuberculosis (TB) in clinical management and endpoint determination in TB vaccine trials. We set out to compare interrater agreement for TB diagnosis in western Kenya. A pediatric pulmonologist and radiologist (experts), a medical officer (M.O), and four clinical officers (C.Os) with basic training in pediatric CXR reading blindly assessed CXRs of infants who were TB suspects in a cohort study. C.Os had access to clinical findings for patient management. Weighted kappa scores summarized interrater agreement on lymphadenopathy and abnormalities consistent with TB. Sensitivity and specificity of raters were determined using microbiologically confirmed TB as the gold standard (n = 8). A total of 691 radiographs were reviewed. Agreement on abnormalities consistent with TB was poor; k = 0.14 (95% CI: 0.10–0.18) and on lymphadenopathy moderate k = 0.26 (95% CI: 0.18–0.36). M.O [75% (95% CI: 34.9%–96.8%)] and C.Os [63% (95% CI: 24.5%–91.5%)] had high sensitivity for culture confirmed TB. TB vaccine trials utilizing expert agreement on CXR as a nonmicrobiologically confirmed endpoint will have reduced specificity and will underestimate vaccine efficacy. C.Os detected many of the bacteriologically confirmed cases; however, this must be interpreted cautiously as they were unblinded to clinical features.

Phytotherapeutic information on plants used for the treatment of tuberculosis in eastern cape province, South Africa

The current rate of deforestation in Africa constitutes a serious danger to the future of medicinal plants on this continent. Conservation of these medicinal plants in the field and the scientific documentation of our knowledge about them are therefore crucial. An ethnobotanical survey of plants used for the treatment of tuberculosis (TB) was carried out in selected areas of the Eastern Cape, South Africa. These areas were Hala, Ncera, Sheshegu, and Gquamashe, all within the Nkonkobe Municipality. One hundred informants were interviewed. The survey included the identification of scientific and vernacular names of the plants used for treatment of TB as well as the methods of preparation and administration, the part used, dosage, and duration of treatment. The survey revealed 30 plants belonging to 21 families which are commonly used by traditional healers for the treatment of TB and associated diseases. Of these plants Clausena anisata, Haemanthus albiflos, and Artemisia afra were the most cited. The leaves were the most common part used in the medicinal preparations. Our findings are discussed in relation to the importance of the documentation of medicinal plants.

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.

Bacillus Calmette-Guérin is a preventive factor in mortality of childhood tuberculous meningitis

OBJECTIVES

Studies have been done that have focused on the efficacy of bacillus Calmette-Guérin (BCG) vaccination in the prevention of cases of childhood tuberculous meningitis (TBM). However the efficacy of the vaccination in the prevention of mortality has not been sufficiently evaluated. This study aimed to determine the main features of TBM cases in childhood and to evaluate the factors related to mortality, proving the protective effect of BCG vaccination in childhood TBM.

METHODS

In a retrospective approach, all consecutive cases of TBM in children that occurred between 1997 and 2005, at Dicle University Hospital, were studied. The following data were evaluated: demographic aspects, admission symptoms, radiology and laboratory findings, BCG vaccination status, tuberculin skin test (TST) positivity, and mortality rates.

RESULTS

In total, 172 cases of childhood TBM were evaluated (mean age 53.3±55.7 months; 109 boys (63.4%)). The majority of these cases (70.4%) had typical TBM symptoms on admission. BCG vaccination data were available for 152 (88.4%) cases and 29 of them (19.1%) were positive. The TST was performed for 143 patients (83.1%) and 28 (19.6%) were found positive. Hydrocephalus was identified in 118 patients (68.6%) on computed tomography examination. A shunt was placed in 79 cases (45.9%). In total, 24 patients (14.0%) died in the hospital. TST negativity was a significant factor for mortality (p=0.012). BCG positivity was found to be a preventive factor from mortality (p=0.05).

CONCLUSIONS

BCG vaccination is effective in the prevention of TBM-associated mortality in childhood. TST negativity may be a sign of a poor prognosis in TBM cases.