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The worldwide burden of disease of bacterial meningitis remains high, despite the decreasing incidence following introduction of routine vaccination campaigns.The aim of our study was to evaluate the epidemiological and bacteriological profile of paediatric bacterial meningitis (BM) in Tunisian children, during the period 2003-2019, following the implementation of Haemophilus influenzae type b (Hib) vaccine (April 2011) and before 10-valent pneumoccocal conjugate vaccine (PCV10) introduction to the childhood immunization program.All bacteriologically confirmed cases of BM admitted to children's hospital of Tunis were recorded (January 2003 to April 2019). Serogroups of Neisseria meningitidis (Nm) and serotypes of Streptococcus pneumoniae (Sp) and H. influenzae (Hi) and antibiotic resistance were determined using conventional and molecular methods.Among 388 cases, the most frequent species were Sp (51.3%), followed by Nm (27.5%) and Hi (16.8%). We observed a significant decrease in Hi BM rate during the conjugated Hib vaccine use period (P < 0.0001). The main pneumococcal serotypes were 14, 19F, 6B, 23F and 19A and the serotype coverage of PCV10, PCV13, PCV15 and PCV20 was 71.3 and 78.8%, 79.4 and 81.9% respectively. The most frequent Nm serogroup was B (83.1%). Most Hi strains were of serotype b (86.9%). High levels of resistance were found: Sp and Nm to penicillin (respectively 60.1 and 80%) and Hi to ampicillin (42.6%). All meningococcal and Hi isolates were susceptible to third-generation cephalosporins and 7.2% of pneumococcal strains had decreased susceptibility to these antibiotics.The Hib conjugate vaccine decreased the rate of BM. Sp dominated the aetiology of BM in children in Tunisia. Conjugate vaccines introducing decreases not only BM cases but also antimicrobial resistance.
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Antibacterianos , Meningites Bacterianas , Neisseria meningitidis , Vacinas Pneumocócicas , Streptococcus pneumoniae , Humanos , Tunísia/epidemiologia , Pré-Escolar , Lactente , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/isolamento & purificação , Streptococcus pneumoniae/efeitos dos fármacos , Meningites Bacterianas/epidemiologia , Meningites Bacterianas/microbiologia , Neisseria meningitidis/classificação , Neisseria meningitidis/isolamento & purificação , Neisseria meningitidis/efeitos dos fármacos , Masculino , Feminino , Criança , Vacinas Pneumocócicas/administração & dosagem , Antibacterianos/farmacologia , Haemophilus influenzae/isolamento & purificação , Haemophilus influenzae/classificação , Haemophilus influenzae/efeitos dos fármacos , Vacinas Anti-Haemophilus/administração & dosagem , Sorogrupo , Farmacorresistência Bacteriana , Testes de Sensibilidade Microbiana , Recém-Nascido , Adolescente , Cápsulas BacterianasRESUMO
INTRODUCTION: Rhinoviruses (HRV) are among the leading causes of Severe Acute Respiratory Infection (SARI). Their burden and genetic diversity vary from one region to another and little is known in Northern African regions. This study describes epidemiological patterns and genotypic diversity of HRV in SARI cases during a two and half year's study, in Northern Tunisia. METHODOLOGY: A total of 271 SARI cases, admitted into the Pediatric Intensive Care Unit of Bechir Hamza Children's Hospital in Tunis, were collected between September 2015 and December 2017. The investigation concerned 104 samples positive for HRV and/or HEV (Human Enterovirus) obtained among these cases. Specific HRV and HEV detections were assessed by real-time PCRs. The HRV molecular typing was based on the VP4-VP2 genomic region analyses. RESULTS: Among the viral SARI cases, 33.5% and 12.3% were positive for HRV and HEV respectively. Molecular investigations showed high prevalence of HRV-A (63.3%) followed by HRV-C (30.6%) and HRV-B (6.1%) and high genotypic diversity with 27 types. HRV cases were mostly detected in toddlers younger than 6 months. A total of 16 cases (28%) were found with bacterial and/or viral co-infection. HRV-C infection and HRV-A with bacterial co-infection were associated with complicated infection. Some of the detected types showed a continuous circulation or turnover during an extended period. HRV-A101 and HRV-C45 were the most frequently detected types. CONCLUSIONS: This study revealed, for the first time, the high HRV diversity in Tunisia, a North-African region. Specific phylogenetic investigations may help to evaluate their diversity and to trace their spread and epidemiological origin.
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Infecções por Picornaviridae/epidemiologia , Rhinovirus/isolamento & purificação , Síndrome Respiratória Aguda Grave/epidemiologia , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Tipagem Molecular , Infecções por Picornaviridae/virologia , Rhinovirus/classificação , Rhinovirus/genética , Síndrome Respiratória Aguda Grave/virologia , Tunísia/epidemiologiaRESUMO
BACKGROUND: Since the 1990s, the epidemiology of bacterial meningitis worldwide has changed thanks to vaccination. In Tunisia, the main causative pathogens were Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae serotype b (Hib). Only Hib vaccination was available during our study period. OBJECTIVES: We performed a laboratory case report based-study of suspected bacterial meningitis in Northern Tunisia from January 2014 to June 2017. METHODS: CSF samples obtained from children beyond neonatal age with suspicion of meningitis were tested by two real time PCRs, targeting pneumococcus, meningococcus and Hib, and conventional methods. RESULTS: Using real-time PCR, 63 were positive including ten supplementary cases compared to conventional methods. A general decrease of bacterial meningitis cases was demonstrated comparing to previous data. Pneumococcus was predominant (69.84%) followed by meningococcus (28.57%) and Hib (1.59%). The main serotypes were 14, 19F, 6B and 23F for pneumococcus and serogroup B for meningococcus. Most cases occurred during cold season and children under one year were the most affected by bacterial meningitis. CONCLUSION: Our study suggests the predominance of pneumococcal cases. It may provide valuable data on meningitis epidemiology before the introduction of pneumococcal vaccine, which may be useful for future evaluation.
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Líquido Cefalorraquidiano/microbiologia , Haemophilus influenzae tipo b/genética , Meningites Bacterianas/epidemiologia , Neisseria meningitidis/genética , Streptococcus pneumoniae/genética , Criança , Pré-Escolar , DNA Bacteriano , Estudos Epidemiológicos , Feminino , Haemophilus influenzae tipo b/isolamento & purificação , Humanos , Lactente , Recém-Nascido , Masculino , Meningites Bacterianas/líquido cefalorraquidiano , Meningites Bacterianas/diagnóstico , Meningites Bacterianas/microbiologia , Neisseria meningitidis/isolamento & purificação , Vigilância da População , Reação em Cadeia da Polimerase em Tempo Real , Estações do Ano , Streptococcus pneumoniae/isolamento & purificação , Tunísia/epidemiologiaRESUMO
The recent increase in pertussis cases observed in some countries may have several causes, including the evolution of Bordetella pertussis populations towards escape of vaccine-induced immunity. Most genomic studies of B. pertussis isolates performed so far are from countries that use acellular vaccines. The objective was to analyse genomic sequences of isolates collected during the 2014 whooping cough epidemic in Tunisia, a country where whole-cell vaccines are used. Ten Tunisian isolates and four vaccine strains were sequenced and compared to 169 isolates from countries where acellular vaccines are used. Phylogenetic analysis showed that Tunisian isolates are diverse, demonstrating a multi-strain 2014 epidemic peak, and are intermixed with those circulating in other world regions, showing inter-country transmission. Consistently, Tunisian isolates have antigen variant composition observed in other world regions. No pertactin-deficient strain was observed. The Tunisian B. pertussis population appears to be largely connected with populations from other countries.
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Bordetella pertussis/genética , Variação Genética , Genoma Bacteriano/genética , Filogenia , Coqueluche/microbiologia , Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/genética , Bordetella pertussis/classificação , Bordetella pertussis/imunologia , Bordetella pertussis/isolamento & purificação , DNA Bacteriano/genética , Humanos , Lactente , Recém-Nascido , Epidemiologia Molecular , Vacina contra Coqueluche/administração & dosagem , Vacina contra Coqueluche/genética , Análise de Sequência de DNA , Tunísia/epidemiologia , Virulência/genética , Fatores de Virulência de Bordetella/genética , Coqueluche/epidemiologia , Coqueluche/transmissãoRESUMO
PURPOSE: Pertussis remains a public health concern in most countries. Our study aimed to prospectively explore the epidemiology of pertussis in the Tunis area of Tunisia between 2007 and 2016, and to characterize the virulence-associated genes of the collected Bordetella pertussis isolates. METHODOLOGY: Infants and children hospitalized at the Children's Hospital of Tunis, Tunisia, between 2007 and 2016 for suspicion of pertussis were enrolled in the study. Culture and real-time PCR (qPCR) assays targeting IS481, IS1001, recA, H-IS1001 and ptxP were used to confirm the pertussis diagnosis. Phenotypic and genotypic characterization of recovered isolates was performed.Results/Key findings. A total of 1844 children were included in the study. Overall, 306 children (16.6â%) with Bordetella infection were confirmed by qPCR. Among them, 265 (86.6â%) were confirmed as having B. pertussis (IS481+, ptxP+, H-IS1001-), 18 (5.9â%) as having Bordetella parapertussis (IS481-, IS1001+) and 11 (3.6â%) as having Bordetella spp. (IS481+, ptxP-, H-IS1001-). No Bordetella holmesii (IS481+, IS1001-, H-IS1001+) was identified. The estimated pertussis incidence in the Tunis area was 134/100â000 in children aged less than 5 years. Two epidemic peaks were observed in 2009 and 2014. Ten B. pertussis isolates were cultured and characterized. Deficiency in pertactin expression was not observed, and genotyping of the isolates revealed a predominant allelic profile: ptxP3-ptxA1-prn2-fim2-1-fim3-2. CONCLUSION: This study demonstrated that pertussis is still present as a cyclical disease in Tunisia, despite high primo-vaccination coverage with a pertussis whole-cell vaccine. The predominant genotype of Tunisian B. pertussis isolates is similar to isolates circulating in countries using the acellular vaccine.
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Bordetella pertussis/isolamento & purificação , Coqueluche/epidemiologia , Coqueluche/microbiologia , Antibacterianos/farmacologia , Bordetella pertussis/classificação , Bordetella pertussis/efeitos dos fármacos , Brônquios/microbiologia , Criança , Pré-Escolar , Tosse , Cianose , Feminino , Genótipo , Humanos , Immunoblotting , Lactente , Recém-Nascido , Masculino , Nasofaringe/microbiologia , Fenótipo , Reação em Cadeia da Polimerase , Estudos Prospectivos , Traqueia/microbiologia , Tunísia/epidemiologiaRESUMO
This cross-sectional study aimed to assess pertussis seroprevalence among healthy healthcare workers (HCW) of the Children's Hospital of Tunis, Tunisia. During the study period, 236 blood samples were obtained to determine HCW exposure to pertussis. Concentrations of immunoglobulin G (IgG) to pertussis toxin (PT) were measured using a commercial enzyme-linked immunosorbent assay. Cut-offs values used were 40 and 100â¯IU/ml, respectively indicative of an infection within the last year and a current/recent infection. Overall, seropositivity rate was 11.4% (95% CI 7.4-15.5) and 2.5% (95% CI 0.5-4.6) of ELISA results were indicative of a current infection. Seroprevalence was significantly most important in nurses (pâ¯=â¯0.03) and in participants aged 21-31y (pâ¯=â¯0.009). Our study confirmed that pertussis is circulating in hospital settings and affecting Tunisian HCW, in close contact with infants. Therefore, a booster dose of acellular pertussis vaccine needs to be considered.
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Pessoal de Saúde/estatística & dados numéricos , Imunoglobulina G/sangue , Toxina Pertussis/imunologia , Coqueluche/epidemiologia , Adulto , Anticorpos Antibacterianos/sangue , Bordetella pertussis/imunologia , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Hospitais/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Vacina contra Coqueluche/administração & dosagem , Estudos Soroepidemiológicos , Tunísia/epidemiologia , Adulto JovemRESUMO
INTRODUCTION: Bacterial meningitis is a medical emergency requiring a fast and reliable diagnosis. Molecular methods such as real-time PCR (rt-PCR) offer an attractive alternative. Thus, this study aims to establish multiplex rt-PCRs detecting N. meningitidis, S. pneumoniae and H. influenzae b from cerebrospinal fluid in Tunisian children beyond neonatal age. METHODOLOGY: Using bioinformatic tools and experimentation, we validated the specificity and optimal criteria of PCRs for primers and probes of plyA (S. pneumoniae), ctrA and sodC (N. meningitidis) and bexA genes (H. influenzae b). We performed one multiplex RT-PCR for detection of S. pneumoniae and N. meningitidis targeting plyA and ctrA, sodC genes respectively, simultaneously with a singleplex RT-PCR for H. influenzae b. The sensitivity and specificity of our methods were assessed. Then, we tested our methods for 122 CSF samples collected from suspected meningitis cases between 2014 and 2016 in Bechir Hamza Children's Hospital of Tunis. RESULTS: Our results have shown the sensitivity of the designed PCRs was up to 10-4 DNA dilution and the specificity was 100%. PCR evaluation has shown 51 positive samples: 38 of pneumococcal cases, 12 meningococcal cases, 1 case of H. influenzae b with 8.57% and 50% of supplementary positive cases rates respectively. CONCLUSIONS: Our assay proved to be very sensitive, specific and rapid for bacterial meningitis diagnosis. In the recent context of Hib vaccination, the possibility of detecting S. pneumoniae and N. meningitidis separately constitute an attractive opportunity. Nevertheless, simultaneous detection of Hib remains relevant in specific clinical context and for epidemiologic study.
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The Global Meningococcal Initiative (GMI) has recently considered current issues in Middle Eastern and African countries, and produced two recommendations: (i) that vaccination of attendees should be considered for some types of mass-gathering events, as some countries mandate for the Hajj, and (ii) vaccination of people with human immunodeficiency virus should be used routinely, because of increased meningococcal disease (MD) risk. Differences exist between Middle Eastern and African countries regarding case and syndrome definitions, surveillance, and epidemiologic data gaps. Sentinel surveillance provides an overview of trends and prevalence of different capsular groups supporting vaccine selection and planning, whereas cost-effectiveness decisions require comprehensive disease burden data, ideally counting every case. Surveillance data showed importance of serogroup B MD in North Africa and serogroup W expansion in Turkey and South Africa. Success of MenAfriVac® in the African "meningitis belt" was reviewed; the GMI believes similar benefits may follow development of a low-cost meningococcal pentavalent vaccine, currently in phase 1 clinical trial, by 2022. The importance of carriage and herd protection for controlling invasive MD and the importance of advocacy and awareness campaigns were also highlighted.
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Surtos de Doenças , Infecções Meningocócicas/epidemiologia , África Subsaariana/epidemiologia , África do Norte/epidemiologia , Humanos , Programas de Imunização , Meningite Meningocócica/epidemiologia , Infecções Meningocócicas/microbiologia , Infecções Meningocócicas/prevenção & controle , Vacinas Meningocócicas/administração & dosagem , Vacinas Meningocócicas/efeitos adversos , Oriente Médio/epidemiologia , Neisseria meningitidis/imunologia , Neisseria meningitidis/isolamento & purificação , Sorogrupo , Turquia/epidemiologia , VacinaçãoRESUMO
AIM: The aims of our study were to characterize phenotypically and genotypically erythromycin-resistant Streptococcus pyogenes or group A streptococci (ERGAS) isolates, to evaluate macrolide resistance and to analyze the association between emm types and virulence factors. Included in this study were all ERGAS strains isolated from 2000 to 2013 at the Children's hospital of Tunis. Antimicrobial susceptibility was performed according to the CA-SFM guidelines. Macrolide resistance genes were revealed by polymerase chain reaction (PCR) method. Virulence factor genes (pyrogenic exotoxin genes and superantigen gene) were detected by PCR, and the emm types were defined by the sequencing of the variable 5' end of the emm gene. RESULTS: Among the 289 GAS isolates collected, 15 (5.2%) were resistant to erythromycin; 7 of the strains were assigned to the cMLSB phenotype (46.6%); 5 harbored ermB gene alone (33.3%); and 2 strains coharbored ermB and mefA (13.3%). The remaining (53.4%) were assigned to the M phenotype and harbored the mefA gene. The frequency of detection of each toxin gene among ERGAS was 13.4% for speA (2 strains), 53.4% for speC (8 strains), and 13.4% for ssa (2 strains). Emm types 1, 58, 11, and 78 were the most frequent among ERGAS strains. The distribution of the cMLSB and M phenotypes changed over the period of investigation with a decrement of cMLSB phenotype and ermB gene that predominated between 2000 and 2006 and an increase of M phenotype and mefA gene between 2007 and 2013, but this difference was nonstatistically significant because of the low number of resistant strains. Emm types 1, 58, and 4 were only present among strains assigned to the M phenotype. However strains assigned to the cMLSB phenotype were associated to emm11, emm22, emm28, emm78, or emm76. There was diversity in emm distribution in ERGAS between the two study periods. There was diversity in emm distribution among ERGAS particularly in 2000-2006. Indeed, from 2000 to 2006, the 6 ERGAS belonged to 5 different emm types (22, 28, 76, 11, and 4), while between 2007 and 2013, seven among the nine ERGAS belonged to only 2 emm types 58 and 1. The speA gene was present only among emm1 isolates, and the ssa gene was associated with emm4 and emm78 types. All emm78, emm28, and emm11 strains harbored speC gene. CONCLUSIONS: Our study revealed a low frequency of ERGAS and few emm types were associated with these strains.
Assuntos
Antibacterianos/farmacologia , Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Transporte/genética , Farmacorresistência Bacteriana/genética , Eritromicina/farmacologia , Genótipo , Streptococcus pyogenes/genética , Fatores de Virulência/genética , Adolescente , Antígenos de Bactérias/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Transporte/metabolismo , Criança , Pré-Escolar , Exotoxinas/genética , Exotoxinas/metabolismo , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Testes de Sensibilidade Microbiana , Fenótipo , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/microbiologia , Streptococcus pyogenes/classificação , Streptococcus pyogenes/efeitos dos fármacos , Streptococcus pyogenes/isolamento & purificação , Superantígenos/genética , Superantígenos/metabolismo , Fatores de Virulência/metabolismoRESUMO
Background Community-acquired pleuropneumonia (CPP) is a common complication of pneumonia in children. It is serious given its high morbidity and significant mortality. Aim To study clinical and paraclinical features of CPP in children and to establish a common therapeutic strategy. Methods Our retrospective study included patients who were hospitalized for CPP between 2004 and 2012. All data were collected from patients' medical files. Statistical analysis was made by Epi-Info 6. Results One hundred and sixty four patients were registered. The mean age was 32 months (15 days - 14.5 years). The hospital incidence of CPP doubled between 2004 and 2012. The symptomatology was dominated by fever (93.9%), cough (56.7%) and dyspnea (48.1%). The pleural effusion was frequently moderately abundant and loculated. Pleural sample, performed in 53.6% of cases, was the most beneficial bacteriological examination (p=10-6 ). The bacteriological confirmation was attained in 44.5% of cases with the predominance of Staphylococcus aureus (59%) followed by Streptococcus pneumoniae (26%). The S. aureus occurred basically in most young infants (p=0.04) and was responsible for the most severe cases (p=0.01). The CPP management included heterogeneous intravenous antibiotics associated with a pleural drainage in 40% of cases. The quarter of our patients were transferred to an intensive care unit. Six patients died. Conclusion The bacteriological confirmation is difficult. Pleural aspiration is the key tool. S. aureus is the first microorganism followed by S. pneumoniae. A therapeutic strategy is proposed based on large spectrum intravenous antibiotics. The pleural drainage indication is limited.
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Infecções Comunitárias Adquiridas/epidemiologia , Derrame Pleural/epidemiologia , Pleuropneumonia/epidemiologia , Adolescente , Animais , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/terapia , Tosse/epidemiologia , Tosse/etiologia , Drenagem/métodos , Dispneia/epidemiologia , Dispneia/etiologia , Feminino , Febre/epidemiologia , Febre/etiologia , Humanos , Lactente , Recém-Nascido , Masculino , Derrame Pleural/microbiologia , Derrame Pleural/terapia , Pleuropneumonia/microbiologia , Pleuropneumonia/terapia , Estudos RetrospectivosRESUMO
BACKGROUND: Critical pertussis is characterized by severe respiratory failure, important leukocytosis, pulmonary hypertension, septic shock and encephalopathy. AIM: To describe the clinical course of critical pertussis, and identify predictors of death at the time of presentation for medical care. METHODOLOGY: Retrospective study conducted in children's hospital Tunisian PICU between 01 January and 31 October 2013. Patients with critical pertussis confirmed by RT-PCR and requiring mechanical ventilation were included. Predictors of death were studied. RESULTS: A total of 17 patients was studied. Median age was 50 days. Mortality was 23%. Predictors risk of mortality were : high PRISM score (Pediatric Risk of Mortality Score) (p=0,007), shock (p=0,002), tachycardia (p=0,005), seizures (p=0,006), altered mental status (p=0,006), elevated WBC count (p=0,003) and hemodynamic support (p=0022). However, the difference did not reach statistical significance in comorbidity, pneumoniae, high pulmonary hypertension or exchange transfusion. Concomitant viral or bacterial co-infection was not related to poor outcome. CONCLUSION: Young infants are at high risk to have critical pertussis. Despite advances in life support and the treatment of organ failure in childhood critical illness, critical pertussis remains difficult to treat.
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The prevalence of plasmid-mediated quinolone resistance genes [qnr, aac(6')-Ib-cr and qepA] was sought among Enterobacteriaceae strains obtained from the Children's Hospital of Tunis (Tunisia). Non-duplicate isolates (nâ=â278) with resistance to extended-spectrum cephalosporins and collected in 2003, 2007, 2008 and 2009 were screened for qnr genes. Forty (14.4â%) isolates were qnr positive and were screened for the presence of the aac(6')-Ib-cr and qepA genes. qnrB was detected in 21 Klebsiella pneumoniae, 11 Escherichia coli and 6 Enterobacter cloacae isolates. Sequence analysis of the qnrB amplicons revealed variants including 24 qnrB1, 11 qnrB2 and 3 qnrB6. qnrS (qnrS1 allele) was detected only in K. pneumoniae isolates, either alone (two isolates) or with the qnrB gene (one isolate). The qnrA, qnrC and qnrD genes were not found in any of the 278 isolates. No qnr-positive isolates carried the qepA gene. Pyrosequencing results showed that aac(6')-Ib-cr, a variant of the aac(6')-Ib gene, was present in 31 qnr-positive isolates (21 K. pneumoniae isolates, seven Escherichia coli isolates and three Enterobacter cloacae isolates). aac(6')-Ib was also found either alone (two isolates) or in association with aac(6')-Ib-cr (one isolate). Of the 40 qnr-positive isolates, 92.5, 82.5, 57.5, 85 and 82.5â% were non-susceptible to nalidixic acid, ciprofloxacin, levofloxacin, ofloxacin and norfloxacin, respectively, and all were extended-spectrum ß-lactamase producers. Random amplified polymorphic DNA-PCR typing of these isolates showed 16, 8 and 5 different genotypes in K. pneumoniae, Escherichia coli and Enterobacter cloacae isolates, respectively. Our study highlights the high prevalence of qnr in association with aac(6')-Ib-cr among Enterobacteriaceae isolates, even from children, who are patients not overtreated with quinolones.
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Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Plasmídeos/análise , Quinolonas/farmacologia , Adolescente , Criança , Pré-Escolar , DNA Bacteriano/química , DNA Bacteriano/genética , Enterobacter cloacae , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Escherichia coli , Feminino , Genes Bacterianos , Variação Genética , Hospitais Pediátricos , Humanos , Lactente , Klebsiella pneumoniae , Masculino , Prevalência , Análise de Sequência de DNA , Tunísia/epidemiologiaRESUMO
The prevalence of pertussis in Tunisia remains undetermined essentially because of the unavailability of a basic laboratory diagnostic service. Specific diagnostic tools were applied for the first time in a Tunisian prospective study in order to get a first estimation of the prevalence of Bordetella pertussis/parapertussis infections and to evaluate their use to determine the epidemiologic characteristics of these infections in Tunisian infants. Between 2007 and 2011, a total of 626 samples from 599 infants aged <1 year with and without pertussoid cough were investigated for the presence of B. pertussis/parapertussis using culture and real-time polymerase chain reaction (PCR). The real-time PCR (RT-PCR) targets include IS481 commonly found in B. pertussis, B. bronchiseptica, and B. holmesii; IS1001 specific of B. parapertussis, in combination with the pertussis toxin promoter region gene (ptx) of B. pertussis; and the recA gene specific of B. holmesii. When possible, patients' household contacts provided nasopharyngeal aspirates (NPAs) for RT-PCR detection of B. pertussis/parapertussis or single-serum samples for anti-PT IgG quantification. All except 1 NPAs were negative by conventional culture, whereas PCR gave positive signals for 126 specimens (21%): B. pertussis, B. parapertussis, and Bordetella spp. were detected in 82%, 6%, and 4% of the samples, respectively. The simultaneous presence of B. pertussis and B. parapertussis was noted in 8% of the cases. Pertussis was reported throughout the year with a peak during the summer of the year 2009. The prevalence of Bordetella infection was 20% between 2007 and 2011. Most of these cases corresponded to patients younger than 6 months who received <3 doses of pertussis vaccine. Among the household contacts enrolled in the study, mothers seemed to be the likely source of infection. This study showed that pertussis is still prevalent in Tunisia and that the disease remains a public health problem affecting not only infants but also adults. Given this situation, sensitive and specific laboratory tests are needed to improve the accuracy of pertussis diagnosis.
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Infecções por Bordetella/epidemiologia , Bordetella parapertussis/isolamento & purificação , Bordetella pertussis/isolamento & purificação , Hospitalização , Coqueluche/epidemiologia , Adulto , Infecções por Bordetella/diagnóstico , Infecções por Bordetella/microbiologia , Bordetella parapertussis/genética , Bordetella pertussis/genética , Pré-Escolar , DNA Bacteriano/análise , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Nasofaringe/microbiologia , Toxina Pertussis , Prevalência , Estudos Prospectivos , Saúde Pública , Reação em Cadeia da Polimerase em Tempo Real , Tunísia/epidemiologia , Coqueluche/diagnóstico , Coqueluche/microbiologiaRESUMO
Despite the introduction of routine vaccination against pertussis for more than a half century, leading to a drastic decline in the number of reported cases, pertussis continues to be an important respiratory disease afflicting unvaccinated infants and previously vaccinated children as well as adults in whom immunity has waned. The diagnosis of pertussis is challenging and accurate laboratory identification of Bordetella infections remains problematic. Common laboratory diagnostic methods used for pertussis diagnosis include culture, direct-fluorescent-antibody testing (DFA), serology and polymerase chain reaction (PCR). Culture of Bordetella pertussis is highly specific but fastidious and has limited sensitivity. DFA provides a much more rapid result, but has the disadvantage of poor sensitivity and specificity. Serology is not useful in infants. In older persons, it is hampered by the limitations of paired sera and it provides mainly a retrospective diagnosis. Such limitations of conventional diagnosis testing have led to the development of PCR assays. Notwithstanding its lack of standardization, PCR has been found to be more sensitive and more specific than other methods. In this report, we aimed to review current knowledge about the available diagnostic methods and tests that accurately diagnose pertussis.
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Bordetella pertussis/isolamento & purificação , Técnicas de Laboratório Clínico/métodos , Coqueluche/diagnóstico , Humanos , Técnicas de Diagnóstico Molecular/métodos , Sensibilidade e Especificidade , Fatores de TempoRESUMO
Despite high vaccination coverage rates, there has been a gradual increase in reported pertussis cases. Although whooping cough affects all ages, young infants continue to suffer the greatest pertussis disease burden. Adolescents and adults are the primary source of infection for young babies. In this paper, we report two cases involving the likely transmission of pertussis from mothers to infants in Tunisia.
Assuntos
Transmissão Vertical de Doenças Infecciosas , Coqueluche/diagnóstico , Coqueluche/transmissão , Adulto , Feminino , Humanos , Lactente , Vacina contra Coqueluche/administração & dosagem , Vacina contra Coqueluche/imunologia , TunísiaRESUMO
Of forty-seven extended-spectrum cephalosporin-resistant Escherichia coli isolates, collected from children at the Children's Hospital in 2006 (Tunis, Tunisia), we analyzed 32 isolates that were genotypically different by enterobacterial repetitive intergenic consensus -polymerase chain reaction. For all isolates, the double-disk diffusion test revealed synergy between clavulanate and cefotaxime and/or ceftazidime, suggesting the production of extended-spectrum beta-lactamases. Polymerase chain reaction experiments, performed on plasmid DNA, and sequencing revealed the presence of bla(TEM-1B) (26 isolates, 81%), bla(TEM-34(IRT-6)) (3 isolates, 9%), bla(SHV-12) (2 isolates, 6%), and bla(CTX-M-15) (31 isolates, 97%). Further, the insertion sequence ISEcp1 was found upstream from the bla(CTX-M-15) gene in 11 isolates. The bla genes were found alone or in various combinations in a single isolate. bla(TEM-1B) and bla(CTX-M-15) genes were detected in 26 out of the 32 isolates. Three isolates harbored both bla(TEM-34(IRT-6)) and bla(CTX-M-15). bla(SHV-12) was identified either alone or with bla(CTX-M-15) in a single isolate. Our investigation showed the dominance of CTX-M-type extended-spectrum beta-lactamases, with CTX-M-15 particularly common, and to our best knowledge, this is the first report of the coexistence of CTX-M-15 and IRT-6 in E. coli isolates from children in Tunisia.
Assuntos
Antibacterianos/farmacologia , DNA Bacteriano/sangue , Infecções por Escherichia coli/genética , Escherichia coli/genética , Escherichia coli/isolamento & purificação , beta-Lactamases/genética , Técnicas de Tipagem Bacteriana , Cefotaxima/farmacologia , Ceftazidima/farmacologia , Criança , Ácido Clavulânico/farmacologia , Elementos de DNA Transponíveis/genética , DNA Intergênico/análise , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana , Escherichia coli/classificação , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Fezes/microbiologia , Humanos , Plasmídeos/metabolismo , Reação em Cadeia da Polimerase , Tunísia , beta-Lactamases/sangueAssuntos
Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana , Farmacorresistência Bacteriana , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/isolamento & purificação , Humanos , Sorotipagem , Streptococcus pneumoniae/efeitos dos fármacos , TunísiaRESUMO
AIM: To evaluate the diagnostic delay and therapeutic insufficiencies delay before the transfer in ICU of the children admitted in the ICU of the children's hospital of Tunis with a purpura fulminans (PF). METHODS: A retrospective, descriptive study, of children with PF referred between January 2000 and January 2006 to a the paediatric intensive care unit (PICU) of the children's hospital of Tunis. The PF diagnosis was retained in any child presenting a feverish purpura and circulatory insufficiency signs. The optimal diagnostic and therapeutic charge taking was defined in three levels: parental, the first line doctors, and the hospital doctors. The symptoms' duration and the various treatments which were lavished to the patients were taken from the medical observations of the patients transferred in our PICU. RESULTS: Twenty one observations were collected. Twelve patients (57.1%) were addressed by a doctor exerting in a dispensary or by a free practicing doctor, 5 patients (23.8%) were transferred from a regional hospital and 4 children (19.1%) directly consulted the children hospital of Tunis urgencies delayed parental recognition occured in 11 children. The PF diagnosis was not evoked by the first line doctor in 62%. Eleven (52.4%) of the children with meningococcal disease were seen but not admitted by a doctor in the 48 hours before admission. Apart from 2 patients (9.5%) who were hospitalized in reanimation directly of the urgencies, all the other patients forwarded by a general pediatry service. In general pediatry, the PF diagnosis was not evoked in 3 cases (15.8%), 31.6% of patients had unnecessary a lumbar punctures and shock was not recognised or treated in 26.3%. Twelve patients (52.2%) died. The duration of hospitalization in general pediatry is significantly higher among deceased patients (5.5 +/- 6.6 hours) than among the surviving patients (2.6 +/- 1.5 hours); p < 0.05. CONCLUSION: Suboptimal treatement in PF is due to failure of parents, general practioners and hospital doctors to recognise specific features of the illness. Improvement in outcome could be achieved by public education and better training of clinicians in recognition, resuscitation, and stabilisation of seriously ill children.
Assuntos
Vasculite por IgA/terapia , Causas de Morte , Criança , Pré-Escolar , Cuidados Críticos , Serviço Hospitalar de Emergência , Departamentos Hospitalares , Hospitalização , Humanos , Vasculite por IgA/diagnóstico , Lactente , Tempo de Internação , Erros Médicos , Corpo Clínico Hospitalar , Pais , Admissão do Paciente , Transferência de Pacientes , Pediatria , Médicos de Família , Encaminhamento e Consulta , Estudos Retrospectivos , Choque/diagnóstico , Punção Espinal , Fatores de Tempo , Procedimentos DesnecessáriosRESUMO
Clinical isolates of Neisseria meningitidis with reduced susceptibility to penicillin G (intermediate isolates, Pen(I)) harbor alterations in the penA gene encoding the penicillin binding protein 2 (PBP2). A 402-bp DNA fragment in the 3' half of penA was sequenced from a collection of 1,670 meningococcal clinical isolates from 22 countries that spanned 60 years. Phenotyping, genotyping, and the determination of MICs of penicillin G were also performed. A total of 139 different penA alleles were detected with 38 alleles that were highly related, clustered together in maximum-likelihood analysis and corresponded to the penicillin G-susceptible isolates. The remaining 101 penA alleles were highly diverse, corresponded to different genotypes or phenotypes, and accounted for 38% of isolates, but no clonal expansion was detected. Analysis of the altered alleles that were represented by at least five isolates showed high correlation with the Pen(I) phenotype. The deduced amino acid sequence of the corresponding PBP2 comprised five amino acid residues that were always altered. This correlation was not complete for rare alleles, suggesting that other mechanisms may also be involved in conferring reduced susceptibility to penicillin. Evidence of mosaic structures through events of interspecies recombination was also detected in altered alleles. A new website was created based on the data from this work (http://neisseria.org/nm/typing/penA). These data argue for the use of penA sequencing to identify isolates with reduced susceptibility to penicillin G and as a tool to improve typing of meningococcal isolates, as well as to analyze DNA exchange among Neisseria species.
Assuntos
Antibacterianos/farmacologia , Genes Bacterianos , Neisseria meningitidis/efeitos dos fármacos , Penicilina G/farmacologia , Proteínas de Ligação às Penicilinas/genética , Análise de Sequência de DNA , Sequência de Aminoácidos , Genótipo , Saúde Global , Humanos , Testes de Sensibilidade Microbiana/métodos , Dados de Sequência Molecular , Neisseria meningitidis/classificação , Neisseria meningitidis/genética , Neisseria meningitidis/isolamento & purificação , Resistência às Penicilinas , Proteínas de Ligação às Penicilinas/metabolismo , Fenótipo , Reação em Cadeia da Polimerase , Recombinação GenéticaRESUMO
A total of 23 invasive strains of Neisseria meningitidis were isolated between March 1998 and February 2004. 19 strains were recovered from cerebrospinal fluid (CSF) and 4 from blood. The majority of these strains were recovered from children with an age less to 4 years (86.9%). The antigenic formula'study (serogroup:serotype:serosubtype) of the strain's collection have shown there great diversity. The sero-group B was the most frequent (83%) followed by serogroup C (17%). The B:NT:NST phenotype was major among strains of the serogroup B and the C:4:P1-14 phenotype among strains of the serogroup C. No beta-lactamase activity was detected. 30.4% of the strains were of diminished susceptibility to penicillin G (CM190 = 0.38 Ig/ml). No resistance to amoxicillin (CMI90 = 0.19 microg/ml), to cefotaxime (CMI90 = 0.016 microg/ml) and to rifampin (CMI90-0.125 microg/ml) was detected; whereas 8.7% of strains-were resistant to chloramphenicol (CMI90=2 Ig/ml) and 65.2% to spiramycin.