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Background Pediatric bacterial meningitis (PBM) causes severe morbidity and mortality within Togo. Thus, as a member of the World Health Organization coordinated Invasive Bacterial Vaccine Preventable Diseases network, Togo conducts surveillance targeting Streptococcus pneumoniae (pneumococcus), Neisseria meningitidis (meningococcus), and Haemophilus influenzae, at a sentinel hospital within the capital city, Lomé, in the southernmost Maritime region. Methods Cerebrospinal fluid was collected from children, Streptococcus pneumoniae was the predominant pathogen responsible for pediatric bacterial meningitis during longitudinal sentinel surveillance within Togo, from 2010 to 2016. However, pneumococcal meningitis cases decreased by 88.1% (52/59) postvaccine introduction; from 59 cases prevaccine introduction to 7 cases postvaccine introduction.

Background Interferon-γ release assays (IGRA) with Resuscitation promoting factor (Rpf) proteins enhanced tuberculosis (TB) screening and diagnosis in adults but have not been evaluated in children. Children often develop paucibacillary TB and their immune response differs from that of adults, which together affect TB disease diagnostics and immunodiagnostics. We assessed the ability of Rpf to identify infection among household TB-exposed children in The Gambia and investigated their ability to discriminate Mycobacterium tuberculosis complex (MTBC) infection from active TB disease in children. Methods Detailed clinical investigations were done on 93 household TB-exposed Gambian children and a tuberculin skin test (TST) was administered to asymptomatic children. Venous blood was collected for overnight stimulation with ESAT-6/CFP-10-fusion protein (EC), purified protein derivative and RpfA, B, C, D and E. Interferon gamma (IFN-γ) production was measured by ELISA in supernatants and corrected for the background level. Infection status was defined by IGRA with EC and TB disease by mycobacterial confirmation and/or clinical diagnosis. We compared IFN-γ levels between infected and uninfected children and between infected and TB diseased children using a binomial logistic regression model while correcting for age and sex. A Receiver Operating Characteristics analysis was done to find the best cut-off for IFN-γ level and calculate sensitivity and specificity. Results Interferon gamma production was significantly higher in infected (IGRA+, n=45) than in uninfected (IGRA-, n=20) children after stimulation with RpfA, B, C, and D (P = 0.03; 0.007; 0.03 and 0.003, respectively). Using RpfB and D-specific IFN-γ cut-offs (33.9 pg/mL and 67.0 pg/mL), infection was classified with a sensitivity-specificity combination of 73%-92% and 77%-72% respectively, which was similar to and better than 65%-75% for TST. Moreover, IFN-γ production was higher in infected than in TB diseased children (n=28, 5 bacteriologically confirmed, 23 clinically diagnosed), following RpfB and D stimulation (P = 0.02 and 0.03, respectively). Conclusion RpfB and RpfD show promising results for childhood MTBC infection screening, and both performed similar to and better than the TST in our study population. Additionally, both antigens appear to discriminate between infection and disease in children and thus warrant further investigation as screening and diagnostic antigens for childhood TB.

We applied a metabonomic strategy to identify host biomarkers in serum to diagnose paediatric tuberculosis (TB) disease. 112 symptomatic children with presumptive TB were recruited in The Gambia and classified as bacteriologically-confirmed TB, clinically diagnosed TB, or other diseases. Sera were analysed using 1H nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS). Multivariate data analysis was used to distinguish patients with TB from other diseases. Diagnostic accuracy was evaluated using Receiver Operating Characteristic (ROC) curves. Model performance was tested in a validation cohort of 36 children from the UK. Data acquired using 1H NMR demonstrated a sensitivity, specificity and Area Under the Curve (AUC) of 69% (95% confidence interval [CI], 56–73%), 83% (95% CI, 73–93%), and 0.78 respectively, and correctly classified 20% of the validation cohort from the UK. The most discriminatory MS data showed a sensitivity of 67% (95% CI, 60–71%), specificity of 86% (95% CI, 75–93%) and an AUC of 0.78, correctly classifying 83% of the validation cohort. Amongst children with presumptive TB, metabolic profiling of sera distinguished bacteriologically-confirmed and clinical TB from other diseases. This novel approach yielded a diagnostic performance for paediatric TB comparable to that of Xpert MTB/RIF and interferon gamma release assays.

Summary Background Diagnosis of tuberculosis (TB) remains difficult, particularly in resource-limited settings. The development of nucleic acid-based tests for detection of Mycobacterium tuberculosis complex (MTBC) has significantly increased sensitivity compared to conventional smear microscopy and provides results within a matter of hours compared to weeks for the current gold-standard, liquid culture. Methods In this study we performed side-by-side comparison of mycobacterial detection assays on sputum samples from 285 subjects presenting with symptoms suggestive of TB in The Gambia and a cross-sectional cohort of 156 confirmed TB patients with a median of 2 months of treatment. A novel assay, Loop-Mediated Amplification test for TB (TB-LAMP), was compared to smear microscopy, MGIT culture and GeneXpert MTB/RIF for all samples. Results When culture was used as the reference standard, we found an overall sensitivity for TB-LAMP of 99% (95% CI: 94.5–99.8) and specificity of 94% (95% CI: 89.3–96.7). When latent class analysis was performed, TB-LAMP had 98.6% (95% CI: 95.9–100) sensitivity and 99% (95% CI: 98.2–100) specificity compared to 91.1% (95% CI: 86.1–96) sensitivity and 100% (95% CI: 98.2–100) specificity for MGIT culture. GeneXpert had the highest sensitivity 99.1% (95% CI: 97.1–100) but the lowest specificity 96% (95% CI: 92.6–98.3). Both TB-LAMP and GeneXpert showed high sensitivity and specificity regardless of age or strain of infection. Conclusion Our findings show the diagnostic utility of both GeneXpert and TB-LAMP in The Gambia. Whilst TB-LAMP requires less infrastructure, it is unable to detect drug-resistant patterns and therefore would be most suitable as a screening test for new TB cases in peripheral health clinics.

SETTING Greater Banjul Area, The Gambia. OBJECTIVE To conduct a pragmatic evaluation of the Xpert(®) MTB/RIF assay in the diagnosis of tuberculosis (TB) among child contacts. DESIGN In this prospective study, one induced sputum sample was obtained from TB contacts aged

Background Childhood tuberculosis (TB) has significant impact on public health worldwide and it is believed that most children acquire TB from an adult smear-positive index case within their household. To further examine this hypothesis and to investigate transmissibility of strains within the household setting, we compared strain-types in adults and their child contacts. We also examined the influence of bacillary burden and strain-type on clinical outcome of contacts. Methods Stored isolates from smear positive adult TB cases (n=136) were selected according to clinical outcomes of their household contacts (children Results The AFB grade of adult index cases correlated with clinical outcome of the children with microbiologically confirmed TB, clinically diagnosed probable TB, asymptomatic but TST positive, and asymptomatic, and TST negative children showed 60%, 35%, 34% and 33% highest AFB grade (3+) levels, respectively. Strain-type determination by spoligotyping showed that 93% of children had acquired Euro-American lineages, while 7% had M. africanum lineage. Combined results for adult index cases of children with confirmed and probable TB showed 76% Mtb-Euro-American, 17% M. africanum and 7% Mtb-Indo-Oceanic. Index cases of TST positive children showed 59% Mtb-Euro-American, 32% M. africanum , 8% Mtb-Indo-Oceanic and 2% Mtb-Beijing. Those of TST negative children showed 63% Mtb-Euro-American, 26% M. africanum , 9% Mtb-Indo-Oceanic and 2% Mtb-Beijing. Conclusions The data so far support other published data, which show that a higher bacillary burden in the index case increases the likelihood of TB transmission to child contacts. Adult patients appear to be more likely to transmit TB if they were carrying Euro-American lineages rather than West African strains.

BackgroundRoutine laboratory diagnostic methods for M. Tuberculosis complex (MTBC) in induced sputum samples such as smear microscopy, GeneXpert and liquid Mycobacteria growth indicator tube (MGIT) culture are often negative due to the paucibacillary nature of childhood tuberculosis. We hypothesise that prolonged incubation beyond routine culture time could potentially improve MTBC detection in specimens.MethodsOut of over 1000 induced sputum samples collected during our childhood TB contact tracing research programme, we randomly selected 102 MTBC-negative MGIT cultures that had either been reported as contaminated (n=35) or negative (n=67) and further incubated these at 37°C for the duration of one month. Ziehl-Neelsen microscopy, MPT64 Antigen secretion and GeneXpert tests were repeated on all samples to detect MTBC. Bacterial DNA was extracted by CTAB method and genotyped using spoligotyping analysis.ResultsOf the 1160 routinely collected induced-sputum samples 12 (1%) were smear-positives; 41 (3.5%) Xpert-positives and 51 (4.4%) MGIT culture MTBC-positives. The remaining MGIT cultures were flagged as contaminated 393 (33.9%) or MTBC-negative 644 (55.5%). After prolonged incubation and retesting of the randomly selected ones, 26/102 (25.5%) were now microscopy-positive, 2/55 (3.63%) were GeneXpert-positive, 8/102 (7.8%) MPT64-Antigen-positive, and 38/102 (37.2%) had readable spoligotyping patterns. The predominant lineages were Mtb-Euro-American 16 (42.1%), Mtb-Indo-Oceanic 11 (28.9%) and M. africanum West African type-2 8 (21%).ConclusionProlonged incubation of routinely MTBC-negative induced-sputum cultures yielded positive results upon retest, highlighting the low sensitivity of routine diagnosis tools on pauci-bacillary paediatric samples. Spoligotyping was more sensitive to detect MTBC compared to GeneXpert. However, prolonged incubation will cause diagnostic delays and thus better strategies are needed to improve timely childhood TB diagnosis.

BACKGROUND: Drug-resistant tuberculosis (TB) is a global public health problem. Adequate management requires baseline drug-resistance prevalence data. In West Africa, due to a poor laboratory infrastructure and inadequate capacity, such data are scarce. Therefore, the true extent of drug-resistant TB was hitherto undetermined. In 2008, a new research network, the West African Network of Excellence for Tuberculosis, AIDS and Malaria (WANETAM), was founded, comprising nine study sites from eight West African countries (Burkina Faso, The Gambia, Ghana, Guinea-Bissau, Mali, Nigeria, Senegal and Togo). The goal was to establish Good Clinical Laboratory Practice (GCLP) principles and build capacity in standardised smear microscopy and mycobacterial culture across partnering laboratories to generate the first comprehensive West African drug-resistance data. METHODS: Following GCLP and laboratory training sessions, TB isolates were collected at sentinel referral sites between 2009-2013 and tested for first- and second-line drug resistance. RESULTS: From the analysis of 974 isolates, an unexpectedly high prevalence of multi-drug-resistant (MDR) strains was found in new (6 %) and retreatment patients (35 %) across all sentinel sites, with the highest prevalence amongst retreatment patients in Bamako, Mali (59 %) and the two Nigerian sites in Ibadan and Lagos (39 % and 66 %). In Lagos, MDR is already spreading actively amongst 32 % of new patients. Pre-extensively drug-resistant (pre-XDR) isolates are present in all sites, with Ghana showing the highest proportion (35 % of MDR). In Ghana and Togo, pre-XDR isolates are circulating amongst new patients. CONCLUSIONS: West African drug-resistance prevalence poses a previously underestimated, yet serious public health threat, and our estimates obtained differ significantly from previous World Health Organisation (WHO) estimates. Therefore, our data are reshaping current concepts and are essential in informing WHO and public health strategists to implement urgently needed surveillance and control interventions in West Africa.

Epidemiological differences exist between Mycobacterium africanum (Maf)- and Mycobacterium tuberculosis (Mtb)-infected patients, but to date, contributing host factors have not been characterised. We analysed clinical outcomes, as well as soluble markers and gene expression profiles in unstimulated, and ESAT6/CFP-10-, whole-Maf- and Mtb-stimulated blood samples of 26 Maf- and 49 Mtb-HIV-negative tuberculosis patients before, and after 2 and 6 months of anti-tuberculosis therapy. Before treatment, both groups had similar clinical parameters, but differed in few cytokines concentration and gene expression profiles. Following treatment the body mass index, skinfold thickness and chest X-ray scores showed greater improvement in the Mtb- compared to Maf-infected patients, after adjusting for age, sex and ethnicity (p = 0.02; 0.04 and 0.007, respectively). In addition, in unstimulated blood, IL-12p70, IL12A and TLR9 were significantly higher in Maf-infected patients, while IL-15, IL-8 and MIP-1α were higher in Mtb-infected patients. Overnight stimulation with ESAT-6/CFP-10 induced significantly higher levels of IFN-γ and TNF-α production, as well as gene expression of CCL4, IL1B and TLR4 in Mtb- compared to Maf-infected patients. Our study confirms differences in clinical features and immune genes expression and concentration of proteins associated with inflammatory processes between Mtb- and Maf-infected patients following anti-tuberculosis treatment These findings have public health implications for treatment regimens, and biomarkers for tuberculosis diagnosis and susceptibility., Author Summary In the Gambia tuberculosis is caused my two major lineages within the Mycobacterium tuberculosis complex (MTBC), M. tuberculosis lineages 4 and M. africanum lineage 6. Our analysis of 26 M. africanum- and 49 M. tuberculosis -HIV-negative tuberculosis patients’ clinic parameters and antigen-stimulated blood cytokines concentration and genes expression reveal that heterogeneous response to standard anti-tuberculosis treatment might depend on the diversity of MTBC lineages. Before treatment, the two groups of patients had similar clinical parameters, but greater improvement was observed in M. tuberculosis- compared to M. africanum -infected patients post-treatment. This was supported by higher production of inflammation-associated cytokines and genes in unstimulated blood samples from M. africanum-infected patients compared to those infected with M. tuberculosis, who instead had higher level of disease resolution cytokines. In contrast, there were lower cytokine responses in antigen-stimulated blood samples of M. africanum- compared to M. tuberculosis-infected patients post-treatment indicating a poorly recovered immune profile. Our results suggest that M. africanum patients respond relatively poorly to the standard anti-tuberculosis treatment or might have a pre-existing defective immune profile; this could explain why they succumb to less virulent mycobacteria.

The predictive value of a combination of clinical and radiological features with interferon-γ release assay (IGRA) for diagnosis of active tuberculosis (TB) disease among TB-exposed children is unknown.150 symptomatic HIV-negative children (aged 3 months to 14 years), prospectively recruited through active contact tracing, were included. Backward stepwise logistic regression and bootstrapping techniques were used for the development and internal validation of a clinical prediction model for active TB disease. Model discrimination and incremental value of a positive IGRA test were assessed by area under the receiver operating characteristic curve (AUC).35 (23%) children were diagnosed with active TB disease and started on treatment and 115 (77%) had other respiratory tract infections. A final parsimonious clinical model, comprising age versus 0.70; p=0.644).A clinical algorithm, including age

The treatment of tuberculosis is based on combinations of drugs that directly target Mycobacterium tuberculosis. A new global initiative is now focusing on a complementary approach of developing adjunct host-directed therapies.\ud \ud Despite the availability of effective antibiotics for tuberculosis (TB) for the past half century, it remains an important global health problem; there are ~9 million active TB cases and ~1.5 million TB-induced deaths per year (see the World Health Organization (WHO) Global Tuberculosis Report in Further information). Health services around the world face major barriers to achieving optimal outcomes from current TB treatment regimens. These barriers include: the spread of multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB); complex and toxic treatment regimens for MDR-TB; HIV co-infection; pharmacokinetic interactions between TB drugs and antiretroviral drugs; relapse; permanent damage to lung and other tissues; long-term functional disability; immune reconstitution inflammatory syndrome (IRIS); and co-morbidity with non-communicable diseases such as diabetes and chronic obstructive airway diseases. Another fundamental problem is the long duration of TB drug treatment (6 months for drug-sensitive TB and at least 18 months for drug-resistant TB) to achieve a cure, owing to the presence of dormant Mycobacterium tuberculosis bacilli that are phenotypically resistant to current classes of anti-TB drugs, which can only target bacterial replication.\ud \ud There is therefore an urgent need for new TB treatments. However, the TB drug pipeline is thin1, 2. For the past 60 years, efforts to develop new treatments have focused on compounds and regimens that target M. tuberculosis directly. Recently, however, attention has focused on investigating a range of adjunct treatment interventions known as host-directed therapies (HDTs) that instead target the host response to infection. Here, we highlight the rationale for HDTs, the current portfolio of HDTs and their mechanisms of action, and a consortium-based approach to drive forward their evaluation in clinical trials.

An 105 Meerschweinchen und 24 Kaninchen wurden zunachst die Beziehungen zwischen Dosis und Infusionsgeschwindigkeit bzw. Applikationsform des INH einerseits und dem Intervall bis zum Auftreten von Krampfen andererseits untersucht. Mogliche Ursachen dieser Latenzzeit bis zur Ausbildung von Konvulsionen werden diskutiert. Der Isoniazidgehalt nach i.v.-Injektion war am hochsten in der Niere, es folgten Leber und Lunge. Die niedrigsten Werte wurden im Hirngewebe gefunden. Intracisternale Injektionen ergaben dagegen niedrige Isoniazid-Werte in Lunge, Leber, Niere und im Serum, aber sehr hohe in Gehirn und Liquor. Bei akuten Isoniazidintoxikationen (Dosen 50 mg/kg und daruber) konnten neben allgemeinen Organveranderungen Parenchymschaden, besonders an Leber und Niere, sowie mitunter seros-toxische Hepatitiden beobachtet werden, die jedoch Verlauf und Prognose der Intoxikation nicht mitbestimmen.

Ectopic teeth in the maxilla in eight patients were localised by roentgenstereo-photogrammetry and the findings confirmed at operation. This new method is likely to be useful in dental surgery.