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1.
Euro Surveill ; 27(29)2022 07.
Article in English | MEDLINE | ID: mdl-35866435

ABSTRACT

Since May 2022, an international monkeypox (MPX) outbreak has been ongoing in more than 50 countries. While most cases are men who have sex with men, transmission is not restricted to this population. In this report, we describe the case of a male child younger than 10 years with MPX in the Netherlands. Despite thorough source tracing, a likely source of infection has not been identified. No secondary cases were identified in close contacts.


Subject(s)
Mpox (monkeypox) , Child , Humans , Male , Mpox (monkeypox)/diagnosis , Mpox (monkeypox)/epidemiology , Monkeypox virus , Netherlands/epidemiology
2.
Cell Microbiol ; 20(9): e12858, 2018 09.
Article in English | MEDLINE | ID: mdl-29749044

ABSTRACT

Central nervous system (CNS) infection by Mycobacterium tuberculosis is one of the most devastating complications of tuberculosis, in particular in early childhood. In order to induce CNS infection, M. tuberculosis needs to cross specialised barriers protecting the brain. How M. tuberculosis crosses the blood-brain barrier (BBB) and enters the CNS is not well understood. Here, we use transparent zebrafish larvae and the closely related pathogen Mycobacterium marinum to answer this question. We show that in the early stages of development, mycobacteria rapidly infect brain tissue, either as free mycobacteria or within circulating macrophages. After the formation of a functionally intact BBB, the infiltration of brain tissue by infected macrophages is delayed, but not blocked, suggesting that crossing the BBB via phagocytic cells is one of the mechanisms used by mycobacteria to invade the CNS. Interestingly, depletion of phagocytic cells did not prevent M. marinum from infecting the brain tissue, indicating that free mycobacteria can independently cause brain infection. Detailed analysis showed that mycobacteria are able to cause vasculitis by extracellular outgrowth in the smaller blood vessels and by infecting endothelial cells. Importantly, we could show that this second mechanism is an active process that depends on an intact ESX-1 secretion system, which extends the role of ESX-1 secretion beyond the macrophage infection cycle.


Subject(s)
Blood-Brain Barrier/microbiology , Central Nervous System Infections/pathology , Host-Pathogen Interactions , Mycobacterium Infections, Nontuberculous/pathology , Mycobacterium marinum/growth & development , Animals , Brain/microbiology , Disease Models, Animal , Macrophages/microbiology , Zebrafish
3.
AIDS Behav ; 23(2): 475-488, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30054766

ABSTRACT

Adherence to antiretroviral therapy (ART) remains a challenge for HIV-infected children. In this cross-sectional study, we used structured interview-administered questionnaires and medical records to measure adherence levels and factors associated with adherence and viral suppression. We included 195 South African children aged 2.1-12.9 on ART. Adherence levels ranged between 20.5% (pill count) and 89.1% (self-report). Boys were less adherent according to self-report, girls were less adherent according to pill count. Caregivers ensured medication was taken when the condition directly affected daily life. Well-functioning families and families with high SES provide a context supportive of adherence. Non-disclosure and difficulties administering medication negatively affected adherence and viral suppression. This study shows challenging levels of adherence impacting directly on viral suppression in a South African paediatric HIV program. Gender roles, non-disclosure and difficulty administering medication may undermine adherence and should be taken into account for clinical guidelines, policy design and inform strategies.


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , Medication Adherence/statistics & numerical data , Social Class , Adolescent , Adult , CD4 Lymphocyte Count , Caregivers , Child , Child, Preschool , Cross-Sectional Studies , Disclosure , Female , HIV Infections/blood , Humans , Male , Quality of Life , Sex Factors , South Africa , Surveys and Questionnaires , Viral Load
4.
J Hum Genet ; 63(1): 93-96, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29215086

ABSTRACT

Most cases of hemolytic uremic syndrome (HUS) are caused by infection with enterohemorrhagic Escherichia coli (EHEC). Genetic defects causing uncontrolled complement activation are associated with the more severe atypical HUS (aHUS). Non-EHEC infections can trigger the disease, however, complement defects predisposing to such infections have not yet been studied. We describe a 2-month-old patient infected with different Gram-negative bacterial species resulting in aHUS. Serum analysis revealed slow complement activation kinetics. Rare variant R229C was found in complement inhibitor vitronectin. Recombinant mutated vitronectin showed enhanced complement inhibition in vitro and may have been a predisposing factor for infection. Our work indicates that genetic changes in aHUS can not only result in uncontrolled complement activation but also increase vulnerability to infections contributing to aHUS.


Subject(s)
Atypical Hemolytic Uremic Syndrome/genetics , Enterohemorrhagic Escherichia coli , Escherichia coli Infections/genetics , Genetic Predisposition to Disease , Point Mutation , Vitronectin/genetics , Atypical Hemolytic Uremic Syndrome/microbiology , Female , Humans , Infant
5.
Trop Med Int Health ; 23(10): 1129-1140, 2018 10.
Article in English | MEDLINE | ID: mdl-30075490

ABSTRACT

OBJECTIVES: To evaluate a paediatric treatment-support intervention for home-based treatment of HIV infection or tuberculous meningitis (TBM). METHODS: A randomised-controlled study comparing local standard care (controls) with standard care plus intervention (combining adherence education, reinforcement and monitoring) in children aged 0-14 years. We recorded adherence measures (self-report, pill-count, drug-assays for isoniazid and rifampicin in urine and pyrazinamide in saliva), difficulties administering medication and PedsQL™questionnaires for health-related quality-of-life (HRQoL) and family impact. RESULTS: In the HIV group (6-months follow-up, n = 195), more children had above-median HRQoL-scores in the intervention group than in the control group (P = 0.009). Problems reported administering medication declined between baseline and follow-up for controls (P = 0.043). Disclosure of HIV status to the child increased between baseline and follow-up in both groups (intervention P < 0.001; control P = 0.031). In the TBM group (3-months follow-up, n = 43), all adherence measures remained high for both intervention and controls, except for rifampicin which declined between baseline and follow-up in the intervention group (P = 0.031). The intervention group maintained above median HRQoL-scores between baseline and follow-up, when the number of children with above-median HRQoL-scores decreased in the controls (P = 0.063). More children in the intervention group had above-median family impact-scores than controls (P = 0.040). CONCLUSIONS: The low-cost, culturally friendly treatment-support intervention had beneficial effects on health-related quality of life, family impact, caregiver disclosure of HIV status to the child, increased caregiver reporting of medication non-adherence and caregiver reporting of difficulties administering medication. Treatment adherence was not significantly affected in either HIV or TBM group.


Subject(s)
Anti-HIV Agents/administration & dosage , Antitubercular Agents/therapeutic use , Child Welfare/statistics & numerical data , HIV Infections/drug therapy , Medication Adherence/statistics & numerical data , Tuberculosis, Meningeal/drug therapy , Adolescent , Child , Child Welfare/psychology , Child, Preschool , Female , HIV Infections/psychology , Humans , Infant , Infant, Newborn , Male , Medication Adherence/psychology , Quality of Life/psychology , South Africa , Tuberculosis, Meningeal/psychology
6.
Crit Care ; 22(1): 105, 2018 Apr 22.
Article in English | MEDLINE | ID: mdl-29679983

ABSTRACT

BACKGROUND: Rapid and accurate diagnosis of neonatal sepsis is highly warranted because of high associated morbidity and mortality. The aim of this study was to evaluate the performance of a novel multiplex PCR assay for diagnosis of late-onset sepsis and to investigate the value of bacterial DNA load (BDL) determination as a measure of infection severity. METHODS: This cross-sectional study was conducted in a neonatal intensive care unit. Preterm and/or very low birth weight infants suspected for late-onset sepsis were included. Upon suspicion of sepsis, a whole blood sample was drawn for multiplex PCR to detect the eight most common bacteria causing neonatal sepsis, as well as for blood culture. BDL was determined in episodes with a positive multiplex PCR. RESULTS: In total, 91 episodes of suspected sepsis were investigated, and PCR was positive in 53 (58%) and blood culture in 60 (66%) episodes, yielding no significant difference in detection rate (p = 0.17). Multiplex PCR showed a sensitivity of 77%, specificity of 81%, positive predictive value of 87%, and negative predictive value of 68% compared with blood culture. Episodes with discordant results of PCR and blood culture included mainly detection of coagulase-negative staphylococci (CoNS). C-reactive protein (CRP) level and immature to total neutrophil (I/T) ratio were lower in these episodes, indicating less severe disease or even contamination. Median BDL was high (4.1 log10 cfu Eq/ml) with a wide range, and was it higher in episodes with a positive blood culture than in those with a negative blood culture (4.5 versus 2.5 log10 cfu Eq/ml; p < 0.0001). For CoNS infection episodes BDL and CRP were positively associated (p = 0.004), and for Staphylococcus aureus infection episodes there was a positive association between BDL and I/T ratio (p = 0.049). CONCLUSIONS: Multiplex PCR provides a powerful assay to enhance rapid identification of the causative pathogen in late-onset sepsis. BDL measurement may be a useful indicator of severity of infection.


Subject(s)
DNA, Bacterial/analysis , Sepsis/diagnosis , Bacterial Load/immunology , Bacterial Load/methods , Blood Culture/methods , Cross-Sectional Studies , DNA, Bacterial/genetics , Female , Gestational Age , Humans , Infant, Newborn , Infant, Premature/blood , Infant, Premature/physiology , Intensive Care Units, Neonatal/organization & administration , Length of Stay/statistics & numerical data , Male , Netherlands , Real-Time Polymerase Chain Reaction/methods
7.
Eur Respir J ; 49(6)2017 06.
Article in English | MEDLINE | ID: mdl-28619953

ABSTRACT

Epidemiological evidence supports vitamin D deficiency as a risk factor for tuberculosis. Differences in solar ultraviolet B (UV-B) exposure, the major source of vitamin D, might therefore partially explain global variation in tuberculosis incidence.In a global country-based ecological study, we explored the correlation between vitamin D-proxies, such as solar UV-B exposure, and other relevant variables with tuberculosis incidence, averaged over the period 2004-2013.Across 154 countries, annual solar UV-B exposure was associated with tuberculosis incidence. Tuberculosis incidence in countries in the highest quartile of UV-B exposure was 78% (95% CI 57-88%, p<0.001) lower than that in countries in the lowest quartile, taking into account other vitamin D-proxies and covariates. Of the explained global variation in tuberculosis incidence, 6.3% could be attributed to variations in annual UV-B exposure. Exposure to UV-B had a similar, but weaker association with tuberculosis notification rates in the multilevel analysis with sub-national level data for large countries (highest versus lowest quartile 29% lower incidence; p=0.057).The potential preventive applications of vitamin D supplementation in high-risk groups for tuberculosis merits further investigation.


Subject(s)
Tuberculosis/epidemiology , Ultraviolet Rays , Vitamin D Deficiency/epidemiology , Analysis of Variance , Ecological and Environmental Phenomena , Environmental Exposure/analysis , Global Health/statistics & numerical data , Humans , Incidence , Risk Factors
8.
BMC Infect Dis ; 16: 251, 2016 06 07.
Article in English | MEDLINE | ID: mdl-27267176

ABSTRACT

BACKGROUND: The defining feature of the cerebrospinal fluid (CSF) collected from infants and children with tuberculous meningitis (TBM), derived from an earlier untargeted nuclear magnetic resonance (NMR) metabolomics study, was highly elevated lactic acid. Undetermined was the contribution from host response (L-lactic acid) or of microbial origin (D-lactic acid), which was set out to be determined in this study. METHODS: In this follow-up study, we used targeted ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) to determine the ratio of the L and D enantiomers of lactic acid in these CSF samples. RESULTS: Here we report for the first time that the lactic acid observed in the CSF of confirmed TBM cases was in the L-form and solely a response from the host to the infection, with no contribution from any bacteria. The significance of elevated lactic acid in TBM appears to be that it is a crucial energy substrate, used preferentially over glucose by microglia, and exhibits neuroprotective capabilities. CONCLUSION: These results provide experimental evidence to support our conceptual astrocyte-microglia lactate shuttle model formulated from our previous NMR-based metabolomics study - highlighting the fact that lactic acid plays an important role in neuroinflammatory diseases such as TBM. Furthermore, this study reinforces our belief that the determination of enantiomers of metabolites corresponding to infectious diseases is of critical importance in substantiating the clinical significance of disease markers.


Subject(s)
Biomarkers/cerebrospinal fluid , Lactic Acid/cerebrospinal fluid , Tuberculosis, Meningeal/cerebrospinal fluid , Cerebrospinal Fluid/chemistry , Child , Child, Preschool , Chromatography, Liquid , Follow-Up Studies , Humans , Infant , Infant, Newborn , Isomerism , Mycobacterium tuberculosis/pathogenicity , Tandem Mass Spectrometry
9.
AIDS Care ; 27(11): 1404-9, 2015.
Article in English | MEDLINE | ID: mdl-26679269

ABSTRACT

Religion has substantial - positive and negative - influence on South Africa's HIV context. This qualitative study explored possibilities for positive church engagement in paediatric HIV care in a rural district in Limpopo Province, South Africa. Opinions, attitudes and experiences of various stakeholders including religious leaders, healthcare workers and people infected/affected with/by HIV were investigated through participant observation, semi-structured interviews and focus group discussions. During the research the original focus on paediatric HIV care shifted to HIV care in general in reaction to participant responses. Participants identified three main barriers to positive church engagement in HIV care: (a) stigma and disclosure; (b) sexual associations with HIV and (c) religious beliefs and practices. All participant groups appreciated the opportunity and relevance of strengthening church involvement in HIV care. Opportunities for positive church engagement in HIV care that participants identified included: (a) comprehensive and holistic HIV care when churches and clinics collaborate; (b) the wide social reach of churches and (c) the safety and acceptance in churches. Findings indicate that despite barriers great potential exists for increased positive church engagement in HIV care in rural South Africa. Recommendations include increased medical knowledge and dialogue on HIV/AIDS within church settings, and increased collaboration between churches and the medical sector.


Subject(s)
Christianity , HIV Infections/psychology , Prejudice , Social Stigma , Social Support , Stereotyping , Adult , Caregivers/psychology , Female , Focus Groups , HIV Infections/drug therapy , Health Personnel/psychology , Humans , Interviews as Topic , Male , Qualitative Research , Rural Population , Socioeconomic Factors , South Africa , Truth Disclosure
10.
Eur J Pediatr ; 173(5): 583-8, 2014 May.
Article in English | MEDLINE | ID: mdl-24257913

ABSTRACT

UNLABELLED: The aim of this study was to determine the prevalence of 25-hydroxyvitamin D (25(OH)D) deficiency in a hospital-based population of both native Dutch and non-Western immigrants and to investigate the influence of immigrant status on the prevalence of vitamin D deficiency. A cross-sectional survey was conducted among 132 patients (1-18 years of age) visiting the paediatric outpatient department. Serum levels of 25(OH)D were measured using high-performance liquid chromatography. Cut-off levels of 30 and 50 nmol/l for serum 25(OH)D were evaluated. One third of the patients had serum 25(OH)D levels below 30 nmol/l, and half of the study population had serum levels below 50 nmol/l. Non-Western immigrants had an increased risk for vitamin D deficiency compared to their native Dutch peers [25(OH)D of <30 nmol/l, p = 0.03, odds ratio (OR) 3.87 (95 % confidence interval (CI) 1.13-13.29); 25(OH)D of <50 nmol/l, p = 0.02, OR 3.57 (95 % CI 1.26-10.14)] with the highest risk for first-generation non-Western immigrants. CONCLUSION: Vitamin D deficiency in the paediatric population is still a matter of concern in the Netherlands, in particular among first-generation non-Western immigrants. We therefore strongly recommend vitamin D supplementation for all non-Western immigrants, regardless of age, skin type or season. Health-care staff who work with non-Western immigrants should be aware of the prevalence and implications of vitamin D deficiency.


Subject(s)
Emigrants and Immigrants , Vitamin D Deficiency/epidemiology , Adolescent , Child , Child, Preschool , Cross-Sectional Studies , Female , Humans , Infant , Male , Netherlands/epidemiology , Prevalence , Risk Factors , Vitamin D Deficiency/drug therapy , Vitamin D Deficiency/ethnology
11.
Front Neurol ; 15: 1403312, 2024.
Article in English | MEDLINE | ID: mdl-39161867

ABSTRACT

There is compelling evidence that a dysregulated immune inflammatory response in neuroinfectious diseases results in modifications in metabolic processes and altered metabolites, directly or indirectly influencing lipid metabolism within the central nervous system (CNS). The challenges in differential diagnosis and the provision of effective treatment in many neuroinfectious diseases are, in part, due to limited understanding of the pathophysiology underlying the disease. Although there are numerous metabolomics studies, there remains a deficit in neurolipidomics research to provide a comprehensive understanding of the connection between altered metabolites and changes in lipid metabolism. The brain is an inherently high-lipid organ; hence, understanding neurolipidomics is the key to future breakthroughs. This review aims to provide an integrative summary of altered cerebrospinal fluid (CSF) metabolites associated with neurolipid metabolism in bacterial and viral CNS infections, with a particular focus on studies that used liquid chromatography-mass spectrometry (LC-MS). Lipid components (phospholipids) and metabolites (carnitine and tryptophan) appear to be the most significant indicators in both bacterial and viral infections. On the basis of our analysis of the literature, we recommend employing neurolipidomics in conjunction with existing neurometabolomics data as a prospective method to enhance our understanding of the cross link between dysregulated metabolites and lipid metabolism in neuroinfectious diseases.

12.
Front Mol Biosci ; 11: 1253983, 2024.
Article in English | MEDLINE | ID: mdl-38560518

ABSTRACT

Tuberculous meningitis (TBM) is a severe form of tuberculosis with high neuro-morbidity and mortality, especially among the paediatric population (aged ≤12 years). Little is known of the associated metabolic changes. This study aimed to identify characteristic metabolic markers that differentiate severe cases of paediatric TBM from controls, through non-invasive urine collection. Urine samples selected for this study were from two paediatric groups. Group 1: controls (n = 44): children without meningitis, no neurological symptoms and from the same geographical region as group 2. Group 2: TBM cases (n = 13): collected from paediatric patients that were admitted to Tygerberg Hospital in South Africa on the suspicion of TBM, mostly severely ill; with a later confirmation of TBM. Untargeted 1H NMR-based metabolomics data of urine were generated, followed by statistical analyses via MetaboAnalyst (v5.0), and the identification of important metabolites. Twenty nine urinary metabolites were identified as characteristic of advanced TBM and categorized in terms of six dysregulated metabolic pathways: 1) upregulated tryptophan catabolism linked to an altered vitamin B metabolism; 2) perturbation of amino acid metabolism; 3) increased energy production-metabolic burst; 4) disrupted gut microbiota metabolism; 5) ketoacidosis; 6) increased nitrogen excretion. We also provide original biological insights into this biosignature of urinary metabolites that can be used to characterize paediatric TBM patients in a South African cohort.

13.
Gut Pathog ; 16(1): 14, 2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38475868

ABSTRACT

BACKGROUND: The pathogenesis of tuberculous meningitis (TBM) involves infection by Mycobacterium tuberculosis in the meninges and brain. However, recent studies have shown that the immune response and inflammatory processes triggered by TBM can have significant effects on gut microbiota. Disruptions in the gut microbiome have been linked to various systemic consequences, including altered immunity and metabolic dysregulation. Inflammation caused by TBM, antibiotic treatment, and changes in host immunity can all influence the composition of gut microbes. This complex relationship between TBM and the gut microbiome is of great importance in clinical settings. To gain a deeper understanding of the intricate interactions between TBM and the gut microbiome, we report innovative insights into the development of the disease in response to treatment. Ultimately, this could lead to improved outcomes, management strategies and quality of life for individuals affected by TBM. METHOD: We used a targeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) approach to investigate metabolites associated with gut metabolism in paediatric participants by analysing the urine samples collected from a control group (n = 40), and an experimental group (n = 35) with confirmed TBM, which were subdivided into TBM stage 1 (n = 8), stage 2 (n = 11) and stage 3 (n = 16). FINDINGS: Our metabolomics investigation showed that, of the 78 initially selected compounds of microbiome origin, eight unique urinary metabolites were identified: 2-methylbutyrlglycine, 3-hydroxypropionic acid, 3-methylcrotonylglycine, 4-hydroxyhippuric acid, 5-hydroxyindoleacetic acid, 5-hydroxyhexanoic acid, isobutyrylglycine, and phenylacetylglutamine as urinary markers of dysbiosis in TBM. CONCLUSION: These results - which are supported by previous urinary studies of tuberculosis - highlight the importance of gut metabolism and of identifying corresponding microbial metabolites as novel points for the foundation of improved management of TBM patients.

14.
BMC Infect Dis ; 13: 340, 2013 Jul 23.
Article in English | MEDLINE | ID: mdl-23879305

ABSTRACT

BACKGROUND: Sensorineural hearing loss is the most common sequela in survivors of bacterial meningitis (BM). In the past we developed a validated prediction model to identify children at risk for post-meningitis hearing loss. It is known that host genetic variations, besides clinical factors, contribute to severity and outcome of BM. In this study it was determined whether host genetic risk factors improve the predictive abilities of an existing model regarding hearing loss after childhood BM. METHODS: Four hundred and seventy-one Dutch Caucasian childhood BM were genotyped for 11 single nucleotide polymorphisms (SNPs) in seven different genes involved in pathogen recognition. Genetic data were added to the original clinical prediction model and performance of new models was compared to the original model by likelihood ratio tests and the area under the curve (AUC) of the receiver operating characteristic curves. RESULTS: Addition of TLR9-1237 SNPs and the combination of TLR2 + 2477 and TLR4 + 896 SNPs improved the clinical prediction model, but not significantly (increase of AUC's from 0.856 to 0.861 and from 0.856 to 0.875 (p = 0.570 and 0.335, respectively). Other SNPs analysed were not linked to hearing loss. CONCLUSIONS: Although addition of genetic risk factors did not significantly improve the clinical prediction model for post-meningitis hearing loss, AUC's of the pre-existing model remain high after addition of genetic factors. Future studies should evaluate whether more combinations of SNPs in larger cohorts has an additional value to the existing prediction model for post meningitis hearing loss.


Subject(s)
Hearing Loss, Sensorineural/genetics , Hearing Loss, Sensorineural/microbiology , Meningitis, Bacterial/complications , Meningitis, Bacterial/genetics , Models, Statistical , Area Under Curve , Chi-Square Distribution , Child , Child, Preschool , Cohort Studies , Female , Genetic Predisposition to Disease , Genotype , Humans , Infant , Male , Netherlands , Polymorphism, Single Nucleotide , ROC Curve , Retrospective Studies , Risk Factors
15.
Minerva Pediatr (Torino) ; 75(2): 224-232, 2023 Apr.
Article in English | MEDLINE | ID: mdl-34918887

ABSTRACT

BACKGROUND: Human Parechovirus (HPeV) and Enterovirus (EV) are known causes of viral infection and meningitis in childhood. Not much is known about the motor development of young Caucasian children after these infections. Most studies in the literature involved Asian children with only EV-71 infection, which is not prevalent in Western countries. METHODS: In this prospective multicenter blinded cohort study we tested the motor function level of children 24 months after an HPeV or EV infection (meningitis or elsewhere) and uninfected peers, with Bayley Scales of Infant Development -3 (BSID-3) and Movement Assessment Battery for Children-2 (M-ABC-2-NL). The total motor outcome, the fine motor function outcome and the gross motor function outcome were measured. Impaired motor development was defined as a z-score ≤-1. RESULTS: Of the 157 analyzed children, the total motor outcome was impaired in 16 (10%), the gross motor function was impaired in 26 (27%) and the fine motor function in 9 (6%) children. There was no significant difference between the outcome of children with a meningitis, an infection elsewhere and uninfected peers. In addition, no differences in motor development were found in a subgroup analysis after correcting for confounders, including age and gender. CONCLUSIONS: No significant differences in motor development were found between HPeV or EV infected and uninfected Dutch children after 24 months of follow-up.


Subject(s)
Enterovirus Infections , Enterovirus , Parechovirus , Picornaviridae Infections , Humans , Child , Picornaviridae Infections/epidemiology , Follow-Up Studies , Cohort Studies , Prospective Studies , Enterovirus Infections/epidemiology
16.
J Clin Immunol ; 32(2): 323-9, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22170315

ABSTRACT

PURPOSE: Children with down syndrome (DS) have an increased susceptibility to infections, due to altered humoral and/or cellular immunity. The aim of this study was to determine the cytokine production in whole blood of children with DS upon stimulation with live influenza A virus. METHODS: Whole blood of 61 children with DS and 57 of their healthy siblings was stimulated with 2.5 × 10(4) TCID50/ml influenza A virus during 6, 24, and 48 h. TNF-α, IL-1ß, IL-6, IL-8, IL-10, IL-12p70, IFN-α, IFN-γ concentrations, and viral load were measured at all time points. RESULTS: At most of the time points, TNF-α, IL-1ß, IL-6, and IL-8 concentrations were significantly higher in children with DS following stimulation with live influenza A virus. IFN-α and IFN-γ levels were also significantly higher in the DS group. Viral clearance, however, was equal in both groups. CONCLUSIONS: Children with DS have an altered immune response to influenza A virus. The production of higher levels of pro-inflammatory cytokines may be responsible for a more severe clinical course of viral disease in these children.


Subject(s)
Cytokines/blood , Down Syndrome/immunology , Inflammation Mediators/blood , Influenza A virus/immunology , Adolescent , Child , Child, Preschool , Cytokines/immunology , Down Syndrome/blood , Down Syndrome/complications , Female , Humans , Inflammation Mediators/immunology , Influenza, Human/complications , Influenza, Human/immunology , Influenza, Human/virology , Male , Viral Load
17.
BMC Infect Dis ; 12: 112, 2012 May 11.
Article in English | MEDLINE | ID: mdl-22577991

ABSTRACT

BACKGROUND: Genetic variation in immune response genes is associated with susceptibility and severity of infectious diseases. Toll-like receptor (TLR) 9 polymorphisms are associated with susceptibility to develop meningococcal meningitis (MM). The aim of this study is to compare genotype distributions of two TLR9 polymorphisms between clinical severity variables in MM survivors. METHODS: We used DNA samples of a cohort of 390 children who survived MM. Next, we determined the genotype frequencies of TLR9 -1237 and TLR9 +2848 polymorphisms and compared these between thirteen clinical variables associated with prognostic factors predicting adverse outcome of bacterial meningitis in children. RESULTS: The TLR9 -1237 TC and CC genotypes were associated with a decreased incidence of a positive blood culture for Neisseria (N.) meningitidis (p = 0.014, odds ratio (OR) 0.5. 95% confidence interval (CI) 0.3 - 0.9). The TLR9 +2848 AA mutant was associated with a decreased incidence of a positive blood culture for N. meningitidis (p = 0.017, OR 0.6, 95% CI 0.3 - 0.9). Cerebrospinal fluid (CSF) leukocytes per µL were higher in patients carrying the TLR9 -1237 TC or CC genotypes compared to carriers of the TT wild type (WT) (p = 0.024, medians: 2117, interquartile range (IQR) 4987 versus 955, IQR 3938). CSF blood/glucose ratios were lower in TLR9 -1237 TC or CC carriers than in carriers of the TT WT (p = 0.017, medians: 0.20, IQR 0.4 versus 0.35, IQR 0.5). CSF leukocytes/µL were higher in patients carrying the TLR9 +2848 AA mutant compared to carriers of GG or GA (p = 0.0067, medians: 1907, IQR 5221 versus 891, IQR 3952). CONCLUSIONS: We identified TLR9 genotypes associated with protection against meningococcemia and enhanced local inflammatory responses inside the central nervous system, important steps in MM pathogenesis and defense.


Subject(s)
Meningitis, Meningococcal/genetics , Meningitis, Meningococcal/immunology , Neisseria meningitidis/immunology , Polymorphism, Single Nucleotide , Toll-Like Receptor 9/genetics , Toll-Like Receptor 9/immunology , Blood/microbiology , Child , Child, Preschool , Cohort Studies , Female , Gene Frequency , Humans , Infant , Male , Neisseria meningitidis/pathogenicity , Severity of Illness Index
18.
Acta Paediatr ; 101(8): 862-7, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22548641

ABSTRACT

AIM: Children with Down syndrome (DS) experience respiratory tract infections (RTIs) more frequently than healthy children. We investigated whether this is related to different immunological characteristics associated with DS. METHODS: The study group consisted of 22 children with DS and 22 of their healthy, age-range matched siblings. Data were collected on infections and hospitalizations because of lower RTIs. Immunoglobulin and IgG subclass levels in blood, as well as lymphocyte and T cell (subset) counts, were determined. RESULTS: The children with DS had a significantly higher frequency of lower RTIs and related hospitalization than their siblings. We also found significantly reduced IgG2 levels as well as significantly lower counts of total lymphocytes, CD4(+) T lymphocytes, CD4(+) invariant natural killer (iNKT) cells and regulatory T cells in the DS group. CONCLUSION: In children with DS, reduced levels of IgG2, total lymphocytes, T lymphocytes, iNKT cells and regulatory T cells might contribute to their higher susceptibility to lower RTIs.


Subject(s)
Adaptive Immunity , Down Syndrome/immunology , Respiratory Tract Infections/immunology , Biomarkers/blood , CD4-Positive T-Lymphocytes/metabolism , Case-Control Studies , Child , Down Syndrome/complications , Female , Heart Defects, Congenital/complications , Heart Defects, Congenital/immunology , Hospitalization/statistics & numerical data , Humans , Immunoglobulin G/blood , Lymphocyte Count , Male , Natural Killer T-Cells/metabolism , Respiratory Tract Infections/complications , Respiratory Tract Infections/epidemiology , Siblings
19.
J Trop Pediatr ; 58(4): 275-9, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22141110

ABSTRACT

INTRODUCTION: In-hospital treatment of children with tuberculous meningitis (TBM) is not a feasible option in many resource-poor countries. Home-based treatment has shown to be a viable alternative. Adherence is an important factor determining success of treatment. OBJECTIVE: Identify possible barriers to adherence of home-based treatment and caretaker perception of the disease. METHOD: A qualitative study consisting of 11 in-depth semi-structured interviews was performed based on principles of the health belief model. RESULTS: Barriers of adherence identified include poor understanding of the disease and transmission route, difficulty with medication administration and side effects, lack of access to the health-care facility, long waiting times and hidden costs of transportation. Caretakers showed good appreciation of the adverse effects of noncompliance and benefits obtained from taking treatment in the home environment. CONCLUSION: Improved doctor-patient communication, information brochures, structural changes to hospital settings, provision of financial and peer support all contribute to optimal TBM home-based treatment.


Subject(s)
Antitubercular Agents/therapeutic use , Caregivers/psychology , Health Knowledge, Attitudes, Practice , Medication Adherence , Tuberculosis, Meningeal/drug therapy , Adult , Child , Child, Preschool , Communication , Female , Health Services Accessibility , Home Care Services/organization & administration , Humans , Infant , Interviews as Topic , Male , Middle Aged , Perception , Professional-Family Relations , Qualitative Research , Socioeconomic Factors , South Africa , Surveys and Questionnaires , Treatment Outcome
20.
Front Neurol ; 13: 804838, 2022.
Article in English | MEDLINE | ID: mdl-35386409

ABSTRACT

Mycobacterium tuberculosis infection, which claims hundreds of thousands of lives each year, is typically characterized by the formation of tuberculous granulomas - the histopathological hallmark of tuberculosis (TB). Our knowledge of granulomas, which comprise a biologically diverse body of pro- and anti-inflammatory cells from the host immune responses, is based mainly upon examination of lungs, in both human and animal studies, but little on their counterparts from other organs of the TB patient such as the brain. The biological heterogeneity of TB granulomas has led to their diverse, relatively uncoordinated, categorization, which is summarized here. However, there is a pressing need to elucidate more fully the phenotype of the granulomas from infected patients. Newly emerging studies at the protein (proteomics) and metabolite (metabolomics) levels have the potential to achieve this. In this review we summarize the diverse nature of TB granulomas based upon the literature, and amplify these accounts by reporting on the relatively few, emerging proteomics and metabolomics studies on TB granulomas. Metabolites (for example, trimethylamine-oxide) and proteins (such as the peptide PKAp) associated with TB granulomas, and knowledge of their localizations, help us to understand the resultant phenotype. Nevertheless, more multidisciplinary 'omics studies, especially in human subjects, are required to contribute toward ushering in a new era of understanding of TB granulomas - both at the site of infection, and on a systemic level.

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