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1.
R I Med J (2013) ; 103(2): 18-20, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32122094

RESUMO

Hospital antibiograms, because they are typically derived from samples obtained from hospitalized patients, may overestimate the prevalence of methicillin resistance in S. aureus in individuals presenting to the hospital for surgery. Because hospital antibiograms are commonly used to justify empiric perioperative prophylactic antibiotic selection prior to surgery, this may lead to unnecessary treatment with broad-spectrum antibiotics such as vancomycin. In a single-institution study, we observed that in our hospital antibiogram the proportion of S. aureus that are methicillin-resistant (MRSA) was significantly higher (45%) than isolates in preoperative nasal cultures obtained at the same hospital in outpatients prior to their lower extremity joint replacement surgery (13%): mean difference 0.32, [95% CI 0.25, 0.39], p <0.0001. These data suggest that hospital antibiograms may overstate the true prevalence of MRSA in those at risk for MRSA surgical site infections who present from the outpatient setting.


Assuntos
Antibacterianos/farmacologia , Portador Sadio/microbiologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Cavidade Nasal/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/isolamento & purificação , Adulto , Antibacterianos/uso terapêutico , Portador Sadio/epidemiologia , Feminino , Humanos , Masculino , Resistência a Meticilina , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Período Pré-Operatório , Prevalência , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/efeitos dos fármacos
2.
Ann Otol Rhinol Laryngol ; 129(1): 5-11, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31390881

RESUMO

OBJECTIVES: Intranasal septal splints are often used in nasal septal surgeries. Routine use of postoperative antibiotics is an accepted practice, although data regarding its efficacy in preventing postsurgical complications are limited. This study aimed to examine bacterial colonization on septal splints following prophylactic antibiotic therapy and the association with postoperative infections. METHODS: Fifty-five patients underwent septoplasty by a single surgeon between March 2015 and April 2016. All had intranasal septal splints and were given antibiotic prophylaxis for 7 days until removal of splints. Nasal cultures were taken before surgery, and septal splints were examined for bacterial colonization following their removal. RESULTS: Thirty-six patients (65%) had positive nasal culture prior to surgery. The most common isolates were Staphylococcus aureus (30%) and Enterobacteriaceae species (66%). All these patients had postoperative bacterial colonization on septal splints. In 15 patients with negative preoperative cultures, bacteria were isolated postoperatively. An increased resistance profile was documented postoperatively in 9 patients (16%), including two with multidrug resistance. In two of these patients preoperative wild-type strains acquired antibiotic resistance postoperatively. No adverse drug reactions to antibiotics were reported. CONCLUSIONS: Increased bacterial growth and emergence of resistant strains were observed on intranasal septal splints despite prophylactic antibiotic treatment. Nonetheless, this did not translate into clinical infection. Thus, considering antibiotics overuse and increasing bacterial resistance, further research is needed to determine the role of antibiotic prophylaxis in the setting of intranasal splints.


Assuntos
Antibacterianos/uso terapêutico , Antibioticoprofilaxia , Cavidade Nasal/microbiologia , Septo Nasal/cirurgia , Procedimentos Cirúrgicos Nasais/métodos , Contenções/microbiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Adolescente , Adulto , Idoso , Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Cefalexina/uso terapêutico , Técnicas de Cultura , Farmacorresistência Bacteriana , Farmacorresistência Bacteriana Múltipla , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/isolamento & purificação , Infecção da Ferida Cirúrgica/epidemiologia , Adulto Jovem
4.
BMC Infect Dis ; 19(1): 899, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31660878

RESUMO

BACKGROUND: Several reports designate the recent increase in community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) nasal carriage. Because of the scanty information regarding the nasal carriage sate of MRSA in the west of Iran, the purpose of the present study was to determine the frequency of CA-MRSA in Sanandaj city. METHODS: Swabs collected from anterior nares of 600 volunteers were analyzed for the presence of S. aureus. The isolates were further investigated for methicillin resistance by using the cefoxitin disk diffusion test, followed by PCR-amplification of the mecA gene. SCCmec types and the presence of the Panton-Valentine Leukocidin (pvl) encoding genes were determined through PCR. Finally, the antimicrobial susceptibility of the isolates was determined by the agar diffusion method. RESULTS: Nasal screening identified 181 S. aureus, of which 55 isolates were MRSA. SCCmec types IV and V were detected in MRSA at frequencies of 80 and 20%, respectively. The overall frequency of pvl genes among the MRSA isolates was 14.54%. MRSA isolates were highly susceptible (98.18%) to mupirocin, gentamicin, and fusidic acid. CONCLUSIONS: The high prevalence of CA-MRSA carriage in the population could pose a serious public health concern for the region. Additionally, advent of drug-resistant pvl-positive strains demands continuous surveillance on the colonization state of CA-MRSA in order to prevent dissemination of the bacterium in the community.


Assuntos
Resistência a Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/genética , Cavidade Nasal/microbiologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Adolescente , Adulto , Idoso , Toxinas Bacterianas/genética , Criança , Pré-Escolar , Estudos Transversais , Exotoxinas/genética , Feminino , Frequência do Gene , Humanos , Lactente , Irã (Geográfico)/epidemiologia , Leucocidinas/genética , Masculino , Programas de Rastreamento , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , Saúde Pública , Fatores de Risco , Adulto Jovem
5.
Mymensingh Med J ; 28(3): 627-633, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31391436

RESUMO

Healthcare providers colonized with Staphylococcus aureus may transmit the organism to patients and community. This study was carried out to determine the rate of nasal colonization of Methicillin resistant Staphylococcus aureus (MRSA) and Vancomycin resistant Staphylococcus aureus (VRSA) among healthcare providers. This cross sectional study was conducted among healthcare providers in a tertiary care hospital, Bangladesh. Nasal swabs from anterior nares of 250 physicians, nurses, and helping staffs working in Dhaka Medical College Hospital were analyzed. Methicillin resistance among MRSA was detected by disc diffusion technique using oxacillin, cefoxitin disc and MIC of oxacillin and methicillin resistance was confirmed by PCR detecting mec-A gene. Considering PCR for mec-A gene as gold standard the sensitivity and specificity of both cefoxitin disc diffusion method and MIC of oxacillin was 100%. Cefoxitin disc diffusion method was better alternative of oxacillin disc diffusion method for detection of MRSA. Nasal colonization by S. aureus was found among 23.2% healthcare providers and 7.2% were colonized with MRSA and no VRSA was detected. MRSA colonization was detected among 5% physicians, 6.43% nurses and 16.67% of helping staffs. Isolated MRSA strains were highly resistant to ciprofloxacin (88.9%), gentamicin (77.8%), erythromycin (72.2%) and Co-trimoxazole (72.2%). All the isolated MRSA were sensitive to linezolid and vancomycin. Periodic screening of healthcare providers should be done to find out MRSA carrier and should be treated accordingly to terminate chain of transmission of the multi-drug resistant organism.


Assuntos
Pessoal de Saúde , Staphylococcus aureus Resistente à Meticilina , Cavidade Nasal , Infecções Estafilocócicas , Antibacterianos , Bangladesh , Estudos Transversais , Humanos , Meticilina , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Cavidade Nasal/microbiologia , Infecções Estafilocócicas/diagnóstico , Staphylococcus aureus , Centros de Atenção Terciária
6.
BMC Infect Dis ; 19(1): 753, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462296

RESUMO

BACKGROUND: Leprosy continues to be a health problem in endemic areas. More than 200,000 new cases of leprosy per year suggest that transmission of the disease is still ongoing, presumably as airborne infection through nasal droplets. Late diagnosis supports continued transmission and increases the individual risk for functional disabilities. Laboratory tools are considered beneficial to facilitate early detection and clinical assessment of cases. The aim of this study was to validate molecular tools allowing detection, quantification and assessment of viability of M. leprae from nasal swab samples which are easy to obtain without the need of any invasive procedures. METHODS: Validation of two real-time PCRs detecting M. leprae DNA (RLEP qPCR) and RNA (16S rRNA RT qPCR) was conducted on "must not detect"/"must detect" samples and 160 pre-treatment nasal swab samples from 20 clinically diagnosed multibacillary (MB) leprosy patients from Togo. RESULTS: Both assays were 100% M. leprae specific and showed analytical sensitivities of three templates each. Out of 20 clinically diagnosed MB leprosy patients, 15 (75.0%) had a positive RLEP qPCR result from nasal swab samples. The 16S rRNA RT qPCR detected viable bacilli in nasal swab samples of ten out of these 15 RLEP positive patients (66.7%). CONCLUSION: The combined RLEP/16S rRNA (RT) qPCR assay provides a sensitive and specific tool to determine the bacterial load and viability of M. leprae from nasal swab samples and is applicable for early diagnosis, monitoring treatment response and investigating the role of nasal carriage of M. leprae in human-to-human transmission through aerosol infection.


Assuntos
Hanseníase/microbiologia , Mycobacterium leprae/genética , Cavidade Nasal/microbiologia , RNA Ribossômico 16S , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , DNA Bacteriano/genética , Humanos , Hanseníase/diagnóstico , Hanseníase Multibacilar/diagnóstico , Hanseníase Multibacilar/microbiologia , Pessoa de Meia-Idade , Mycobacterium leprae/isolamento & purificação , Mycobacterium leprae/patogenicidade , RNA Ribossômico 16S/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Togo , Adulto Jovem
7.
PLoS One ; 14(7): e0218511, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31276521

RESUMO

BACKGROUND: Use of hormonal contraceptives has been associated with Staphylococcus aureus nasal carriage in adult women. However, the role of hormonal contraceptives in S. aureus colonization among adolescents and associations with progestin only contraceptives are unknown. METHODS: We obtained nasal and throat swab samples from 439 girls aged 17-21 years in the population-based Tromsø study Fit Futures, 2012-2013, Norway, with information on lifestyle, health and biomarkers. We used multivariable logistic regression to study the association between use of hormonal contraceptives and Staphylococcus aureus carriage while adjusting for potential confounding factors. RESULTS: Staphylococcus aureus nasal carriage prevalence were 34%, 42%, and 61% among progestin-only users, non-users, and progestin-estrogen combination contraceptive users, respectively (P<0.001). Use of combination contraceptives doubled the odds of nasal carriage (non-users reference; OR = 2.31, 95%CI = 1.43-3.74). The OR of nasal carriage was 0.29 among progestin-only users compared to combination contraceptives users (95% CI = 0.12-0.67). DISCUSSION: In this study, use of combination hormonal contraceptives was associated with higher risk of Staphylococcus aureus nasal carriage in adolescent girls. Experimental design studies are needed to establish the role of exogenous sex steroids in Staphylococcus aureus colonization in women.


Assuntos
Comportamento Contraceptivo , Anticoncepcionais Orais Hormonais/administração & dosagem , Estrogênios , Cavidade Nasal/microbiologia , Faringe/microbiologia , Progestinas , Staphylococcus aureus , Adolescente , Adulto , Estrogênios/administração & dosagem , Estrogênios/efeitos adversos , Feminino , Humanos , Noruega/epidemiologia , Prevalência , Progestinas/administração & dosagem , Progestinas/efeitos adversos , Fatores de Risco , Infecções Estafilocócicas/induzido quimicamente , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/isolamento & purificação , Adulto Jovem
8.
Eur J Clin Microbiol Infect Dis ; 38(11): 2037-2044, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31332610

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) nasal carriage is a major risk factor for infection, namely among populations in the community with inherent prompting factors, such as the homeless. In Portugal, there are no data on S. aureus/MRSA nasal carriage among the homeless community. A total of 84 homeless individuals living in Lisbon (34 with no permanent address and 50 living in shelter) were nasally screened for S. aureus/ MRSA. All isolates were characterized to determine antimicrobial susceptibility and clonal type. A total of 43 (51.2%) S. aureus carriers were identified, including a single individual colonized with MRSA (1.2%). S. aureus carriage rate was higher among individuals with no permanent address (58.8% versus 46%), younger (45.7 ± 12.7 versus 52.5 ± 10.8 years), and with diagnosis of asthma (9% versus 0%). The single MRSA belonged to the EMRSA-15 clone (PFGE D, ST15-SCCmec IVh, and spa type t790). Almost half of the methicillin-susceptible S. aureus (MSSA) isolates (41.9%, n = 18) belonged to two major clones, ST398-t1451 (n = 13) and ST30-t399/t11980/t12808 associated with PFGE I (n = 5). A high proportion of isolates showed non-susceptibility to mupirocin (64%), erythromycin (45%), and fusidic acid (20%) and induced resistance to clindamycin (39%). None of the isolates harboured PVL. Our results suggest that the homeless population of Lisbon does not constitute a reservoir of MRSA in the community, but harbour the highly transmissible ST398-t1451 MSSA lineage.


Assuntos
Portador Sadio/epidemiologia , Pessoas em Situação de Rua/estatística & dados numéricos , Cavidade Nasal/microbiologia , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/isolamento & purificação , Adulto , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana , Portador Sadio/microbiologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Feminino , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Portugal/epidemiologia , Prevalência , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética
9.
Int J Syst Evol Microbiol ; 69(9): 2928-2935, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31310200

RESUMO

Three Gram-stain-positive, rod-to-coccoid-shaped, catalase-positive and non-motile bacterial strains isolated from the choanae of a Northern bald ibis, designated strains 200CHT, W8T and 812CHT, respectively, were subjected to comprehensive taxonomic characterization. The three strains were oxidase-negative. The 16S rRNA gene sequence of 200CHT showed highest similarities to Corynebacterium epidermidicanis 410T (96.7 %) followed by Corynebacterium argentoratense DSM 44202T, Corynebacterium ulcerans NCTC 7910T and Corynebacterium pseudotuberculosis CIP 102968T (each 96.3 %). Strains W8T and 812CHT both showed highest 16S rRNA gene sequence similarities to Corynebacterium pelargi 136/3T (98.0 and 99.9 %, respectively). Comparison of the partial housekeeping gene sequence of fusA showed higher sequence similarities of 812CHT to C. pelargi (95.8 %) than W8T (90.9 %) which was also confirmed by corresponding amino acid sequences. In both, fusA gene and corresponding protein sequence strain 200CHT showed low sequence similarities to C. epidermidicanis 410T(81.6 and 87.4 %, respectively). Strains 812CHT and W8T had 76.7 % ANI similarity to each other and 88.2 and 76.4 % to C. pelargi 136/3T, respectively. In silico DNA-DNA hybridization values for 812CHT and W8T were 22.1 % among the two strains and 35.3 and 21.7 % to C. pelargi 136/3T, respectively. These data not only demonstrate that strain W8T is a representative of a novel species, but despite the high 16S rRNA gene sequence similarity to C. pelargi, strain 812CHT is also a representative of another novel species. All three strains possessed corynemycolic acids and contained meso-diaminopimelic acid as the diagnostic diamino acid of the peptidoglycan. The two strains, 200CHT and W8T, are distinguished from each other and established Corynebacterium species phylogenetically and phenotypically. In conclusion, three novel species of the genus Corynebacterium are proposed, namely Corynebacteriumpseudopelargi 812CHT (=LMG 30627T=CCM 8832T), Corynebacterium choanae 200CHT (=LMG 30628T=CCM 8831T) and Corynebacteriumgerontici W8T (=LMG 30629T=CCM 8833T), respectively.


Assuntos
Aves/microbiologia , Corynebacterium/classificação , Cavidade Nasal/microbiologia , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Corynebacterium/isolamento & purificação , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Genes Bacterianos , Hibridização de Ácido Nucleico , Peptidoglicano/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
10.
Artigo em Inglês | MEDLINE | ID: mdl-31165051

RESUMO

The nasal mucosa provides first line defense against inhaled pathogens while creating a unique microenvironment for bacterial communities. Studying the impact of microbiota in the nasal cavity has been difficult due to limitations with current models including explant cultures, primary cells, or neoplastic cell lines. Most notably, none have been shown to support reproducible colonization by bacterial communities from human donors. Therefore, to conduct controlled studies of the human nasal ecosystem, we have developed a novel ex vivo mucosal model that supports bacterial colonization of a cultured host mucosa created by immortalized human nasal epithelial cells (NEC). For this model, immortalized NEC established from 5 male and 5 female donors were cultured with an air-interfaced, apical surface on a porous transwell membrane. NEC were grown from nasal turbinate tissues harvested from willed bodies or from discarded tissue collected during sinonasal procedures. Immortalized cells were evaluated through molecular verification of cell type, histological confirmation of tissue differentiation including formation of tight junctions, NEC multilayer viability, metabolism, physiology and imaging of the luminal surface by scanning electron microscopy. Results showed proper differentiation and multilayer formation at seven to 10 days after air interface that was maintained for up to 3 weeks. The optimized mucosal cultures created an environment necessary to sustain colonization by nasal microbiomes (NMBs) that were collected from healthy volunteers, cryogenically preserved and characterized with customized quantitative polymerase chain reaction (qPCR) arrays. Polymicrobial communities of nasal bacteria associated with healthy and inflamed states were consistently reproduced in matured NEC co-cultures by transplant of NMBs from multiple community types. The cultured NMBs were stable after an initial period of bacterial replication and equilibration. This novel ex vivo culture system is the first model that supports controlled cultivation of NMBs, allowing for lab-based causation studies and further experimentation to explore the complexities of host-microbe and microbe-microbe interactions.


Assuntos
Células Epiteliais/microbiologia , Microbiota , Cavidade Nasal/microbiologia , Mucosa Nasal/microbiologia , Bactérias , Linhagem Celular , Células Imobilizadas , Técnicas de Cultura , Ecossistema , Células Epiteliais/imunologia , Feminino , Humanos , Masculino , Interações Microbianas , Cavidade Nasal/imunologia , Mucosa Nasal/imunologia , Texas , Voluntários
11.
Medicine (Baltimore) ; 98(18): e15499, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31045837

RESUMO

Given the emergence of community-acquired methicillin-resistant Staphylococcus aureus (MRSA) as a global health threat, understanding the risk factors for MRSA infection in the community may be a reasonable strategy to prevent it. We investigated the associations between serum homocysteine levels and prevalence of nasal colonization with S aureus and MRSA among United States adults. We conducted a cross-sectional analysis of a nationally representative sample of 7832 adults (20 years or older). The main outcome variables were nasal colonization with S aureus and MRSA. Percentages of colonization with S aureus and MRSA were calculated by the quartiles of serum homocysteine. A total of 7832 of 2051 subjects (26.2%) were culture positive for S aureus, 98 (4.8%) of whom had nasal colonization with MRSA. In comparison with subjects having the lowest serum homocysteine, the odds of nasal colonization with MRSA were significantly higher in those with the highest homocysteine (odds ratio, 3.09; 95% confidence interval, 1.11-8.61) in multivariate analysis, adjusted for all confounding variables. By contrast, homocysteine elevation was not significantly associated with S aureus colonization. Nasal colonization with MRSA in the general community was significantly associated with increases in serum homocysteine levels.


Assuntos
Homocisteína/sangue , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Cavidade Nasal/microbiologia , Infecções Estafilocócicas/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Contagem de Colônia Microbiana , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Razão de Chances , Prevalência , Fatores de Risco , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Estados Unidos/epidemiologia , Adulto Jovem
12.
Thorax ; 74(6): 592-599, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31076501

RESUMO

BACKGROUND: Emerging evidence shows that airway microbiota may modulate local immune responses, thereby contributing to the susceptibility and severity of acute respiratory infections (ARIs). However, there are little data on the longitudinal relationships between airway microbiota and susceptibility to ARIs in children. OBJECTIVE: We aimed to investigate the association of early nasal microbiota and the subsequent risk of ARIs during the first years of life. METHODS: In this prospective population-based birth-cohort study in Finland, we followed 839 healthy infants for ARIs from birth to age 24 months. Nasal microbiota was tested using 16S rRNA gene sequencing at age 2 months. We applied an unsupervised clustering approach to identify early nasal microbiota profiles, and examined the association of profiles with the rate of ARIs during age 2-24 months. RESULTS: We identified five nasal microbiota profiles dominated by Moraxella, Streptococcus, Dolosigranulum, Staphylococcus and Corynebacteriaceae, respectively. Incidence rate of ARIs was highest in children with an early Moraxella-dominant profile and lowest in those with a Corynebacteriaceae-dominant profile (738 vs 552/100 children years; unadjusted incidence rate ratio (IRR), 1.34; 95% CI 1.16 to 1.54; p < 0.001). After adjusting for nine potential confounders, the Moraxella-dominant profile-ARI association persisted (adjusted IRR (aIRR), 1.19; 95% CI 1.04 to 1.37; p = 0.01). Similarly, the incidence rate of lower respiratory tract infections (a subset of all ARIs) was significantly higher in children with an early Moraxella-dominant profile (aIRR, 2.79; 95% CI 1.04 to 8.09; p = 0.04). CONCLUSION: Moraxella-dominant nasal microbiota profile in early infancy was associated with an increased rate of ARIs during the first 2 years of life.


Assuntos
Microbiota , Cavidade Nasal/microbiologia , Infecções Respiratórias/microbiologia , Doença Aguda , Corynebacterium/isolamento & purificação , Suscetibilidade a Doenças , Feminino , Finlândia/epidemiologia , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Moraxella/isolamento & purificação , Estudos Prospectivos , Infecções Respiratórias/epidemiologia , Staphylococcus/isolamento & purificação , Streptococcus/isolamento & purificação
13.
BMC Infect Dis ; 19(1): 478, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31142269

RESUMO

BACKGROUND: Staphylococcus aureus and beta-hemolytic streptococci (BHS) diseases disproportionately affect populations in middle/low-income countries. To assess if this disparity is reflected in colonization by these organisms, we compared their colonization frequency among children from different socioeconomic status (SES) communities in a city with high income inequality. METHODS: Between May-August 2014, we collected nasal and throat swabs to investigate S. aureus and BHS colonization among children who attended private and public pediatric clinics. Patients were classified as high SES, middle/low SES, and slum residents. We investigated the antimicrobial resistance profile, the SCCmec types and the presence of PVL genes among methicillin-resistant S. aureus (MRSA). We also examined the antimicrobial resistance profile and serogroups of BHS. RESULTS: Of 598 children, 221 (37%) were colonized with S. aureus, of which 49 (22%) were MRSA. MRSA colonization was higher in middle/low SES (n = 18; 14%) compared with high SES (n = 17; 6%) and slum (n = 14; 8%) residents (p = 0.01). All MRSA strains were susceptible to clindamycin, nitrofurantoin, and rifampin. The highest non-susceptibility frequency (42.9%) was observed to erythromycin. SCCmec type V was only found in isolates from high SES children; types I and II were found only in middle/low SES children. Ten (20%) MRSA isolates carried PVL genes. Twenty-four (4%) children were BHS carriers. All BHS (n = 8) found in high SES children and six (67%) isolates from slum patients belonged to group A. All group B streptococci were from middle/low SES children, corresponding to five (71%) of the seven BHS isolated in this group. BHS isolates were susceptible to all drugs tested. CONCLUSIONS: Children from different SES communities had distinct bacterial colonization profiles, including MRSA carriage. Public health officials/researchers should consider SES when assessing disease transmission and control measures.


Assuntos
Farmacorresistência Bacteriana , Infecções por Bactérias Gram-Positivas/diagnóstico , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Criança , Pré-Escolar , Estudos Transversais , Farmacorresistência Bacteriana/efeitos dos fármacos , Feminino , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Cavidade Nasal/microbiologia , Fatores de Risco , Fatores Socioeconômicos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Streptococcus/efeitos dos fármacos , Streptococcus/genética , Streptococcus/isolamento & purificação
14.
J Anim Sci ; 97(6): 2368-2375, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31144716

RESUMO

Disease incidence is intimately associated with an animal's commensal bacteria populations (microbiome), as microbes that are involved with morbidity and mortality are commonly found in animals with no sign of disease. An understanding of the animal's resident respiratory pathogens, in the upper nasal cavity prior to weaning, may help us to understand the impact of these pathogens on incidence of respiratory disease. For this research, the overall goal was to characterize bacterial populations associated with calves at an early age and through time periods prior to weaning in 3 herds at the U.S. Meat Animal Research Center. Nasal swabs from the upper nasal cavity were collected at initial vaccination (approximately 40 d of age), preconditioning (approximately 130 d of age), and weaning (approximately 150 d of age) in 2015 and 2016. DNA was extracted from nasal swabs and combined into 2 pools of 10 animals for each sampling time point, in each herd, for a total of 6 pools at each sampling time point and 18 pools for all sampling time points within each year. To evaluate and compare the microbiome of each pooled sample, hypervariable regions 1 through 3 along the 16S ribosomal RNA (rRNA) gene were amplified by PCR and sequenced using next-generation sequencing (Illumina MiSeq) for identification of the bacterial taxa present. Alpha and beta diversity were also measured. Overall, microbial communities were different between combinations of sampling year, herd location, and sampling time prior to weaning as shown by beta diversity. Analysis of these specific respiratory pathogens prior to weaning will present a clearer picture of the distribution of microbial populations in animals prior to weaning and not exhibiting clinical signs of respiratory disease. Therefore, evaluation of the animal's resident bacterial populations in the upper nasal cavity during different phases of the beef production system may help us to understand the impact of the microbiome on incidence of respiratory disease in cattle.


Assuntos
Bactérias/classificação , Doenças dos Bovinos/epidemiologia , Bovinos/microbiologia , Microbiota , Infecções Respiratórias/veterinária , Animais , Bactérias/genética , Biodiversidade , Doenças dos Bovinos/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala/veterinária , Incidência , Cavidade Nasal/microbiologia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/microbiologia , Análise de Sequência de DNA , Simbiose , Estados Unidos/epidemiologia , Desmame
15.
PLoS Pathog ; 15(4): e1007696, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30970038

RESUMO

Infection and inflammation of the middle ears that characterizes acute and chronic otitis media (OM), is a major reason for doctor visits and antibiotic prescription, particularly among children. Nasopharyngeal pathogens that are commonly associated with OM in humans do not naturally colonize the middle ears of rodents, and experimental models in most cases involve directly injecting large numbers of human pathogens into the middle ear bullae of rodents, where they induce a short-lived acute inflammation but fail to persist. Here we report that Bordetella pseudohinzii, a respiratory pathogen of mice, naturally, efficiently and rapidly ascends the eustachian tubes to colonize the middle ears, causing acute and chronic histopathological changes with progressive decrease in hearing acuity that closely mimics otitis media in humans. Laboratory mice experimentally inoculated intranasally with very low numbers of bacteria consistently have their middle ears colonized and subsequently transmit the bacterium to cage mates. Taking advantage of the specifically engineered and well characterized immune deficiencies available in mice we conducted experiments to uncover different roles of T and B cells in controlling bacterial numbers in the middle ear during chronic OM. The iconic mouse model provides significant advantages for elucidating aspects of host-pathogen interactions in otitis media that are currently not possible using other animal models. This natural model of otitis media permits the study of transmission between hosts, efficient early colonization of the respiratory tract, ascension of the eustachian tube, as well as colonization, pathogenesis and persistence in the middle ear. It also allows the combination of the powerful tools of mouse molecular immunology and bacterial genetics to determine the mechanistic basis for these important processes.


Assuntos
Infecções por Bordetella/transmissão , Bordetella/patogenicidade , Modelos Animais de Doenças , Tuba Auditiva/microbiologia , Cavidade Nasal/microbiologia , Otite Média/microbiologia , Animais , Infecções por Bordetella/complicações , Infecções por Bordetella/microbiologia , Doença Crônica , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL
16.
PLoS Comput Biol ; 15(4): e1006534, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31009452

RESUMO

Bacterial populations that colonize a host can play important roles in host health, including serving as a reservoir that transmits to other hosts and from which invasive strains emerge, thus emphasizing the importance of understanding rates of acquisition and clearance of colonizing populations. Studies of colonization dynamics have been based on assessment of whether serial samples represent a single population or distinct colonization events. With the use of whole genome sequencing to determine genetic distance between isolates, a common solution to estimate acquisition and clearance rates has been to assume a fixed genetic distance threshold below which isolates are considered to represent the same strain. However, this approach is often inadequate to account for the diversity of the underlying within-host evolving population, the time intervals between consecutive measurements, and the uncertainty in the estimated acquisition and clearance rates. Here, we present a fully Bayesian model that provides probabilities of whether two strains should be considered the same, allowing us to determine bacterial clearance and acquisition from genomes sampled over time. Our method explicitly models the within-host variation using population genetic simulation, and the inference is done using a combination of Approximate Bayesian Computation (ABC) and Markov Chain Monte Carlo (MCMC). We validate the method with multiple carefully conducted simulations and demonstrate its use in practice by analyzing a collection of methicillin resistant Staphylococcus aureus (MRSA) isolates from a large recently completed longitudinal clinical study. An R-code implementation of the method is freely available at: https://github.com/mjarvenpaa/bacterial-colonization-model.


Assuntos
Biologia Computacional/métodos , Interações Hospedeiro-Patógeno/fisiologia , Staphylococcus aureus Resistente à Meticilina , Modelos Biológicos , Infecções Estafilocócicas/microbiologia , Algoritmos , Teorema de Bayes , Portador Sadio/microbiologia , Simulação por Computador , Humanos , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Staphylococcus aureus Resistente à Meticilina/fisiologia , Cavidade Nasal/microbiologia
17.
Microbiol Spectr ; 7(2)2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-31004422

RESUMO

Staphylococcus aureus is usually regarded as a bacterial pathogen due to its ability to cause multiple types of invasive infections. Nevertheless, S. aureus colonizes about 30% of the human population asymptomatically in the nares, either transiently or persistently, and can therefore be regarded a human commensal as well, although carriage increases the risk of infection. Whereas many facets of the infection processes have been studied intensively, little is known about the commensal lifestyle of S. aureus. Recent studies highlight the major role of the composition of the highly variable nasal microbiota in promoting or inhibiting S. aureus colonization. Competition for limited nutrients, trace elements, and epithelial attachment sites, different susceptibilities to host defense molecules and the production of antimicrobial molecules by bacterial competitors may determine whether nasal bacteria outcompete each other. This chapter summarizes our knowledge about mechanisms that are used by S. aureus for efficient nasal colonization and strategies used by other nasal bacteria to interfere with its colonization. An improved understanding of naturally evolved mechanisms might enable us to develop new strategies for pathogen eradication.


Assuntos
Fenômenos Fisiológicos Bacterianos , Microbiota , Cavidade Nasal/microbiologia , Staphylococcus aureus/crescimento & desenvolvimento , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Humanos , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/fisiologia
18.
Ann Otol Rhinol Laryngol ; 128(9): 819-828, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31014081

RESUMO

OBJECTIVE: The aim of the present study is to determine and compare the range of pH value in nasal and sinus cavities in vivo regarding the presence of bacteria colonizing sinonasal mucosa among healthy subjects. METHODS: The nasal pH value measurement using a portable pH meter (Dx-pH System, Restech) and the microbiological culture swab were taken from beneath the middle turbinate and in the sinus cavity in 39 healthy subjects during maxillary bone corrective osteotomy with the Le Fort I technique. RESULTS: The mean pH value (independently of sex, P = .441) in the healthy sinus cavity was statistically higher than in the nasal middle meatus: 7.96 (SD ± 0.29) versus 7.83 (SD ± 0.30) (P = .032). Forty-eight strains of bacteria were cultured from sinus maxillaries cavities-aerobic 36.8%, aerobic and anaerobic 52.6%, anaerobic only 10.5%-and 23 strains from the nasal meatus-aerobic 25%, aerobic and anaerobic 75%. A statistically significant correlation was found between the type and location of 8 microorganisms, especially Propionibacterium acnes, identified only in the sinus cavities. CONCLUSIONS: Differences in the pH value between the middle nasal meatus and the maxillary sinus are characteristic of healthy subjects and could be associated with the diverse bacterial flora. The role of bacteria Propionibacterium acnes seems to be crucial for the pH range and sinus flora in healthy subjects.


Assuntos
Seio Maxilar , Cavidade Nasal , Propionibacterium acnes/isolamento & purificação , Adulto , Correlação de Dados , Feminino , Voluntários Saudáveis , Humanos , Concentração de Íons de Hidrogênio , Masculino , Seio Maxilar/química , Seio Maxilar/microbiologia , Microbiota , Pessoa de Meia-Idade , Cavidade Nasal/química , Cavidade Nasal/microbiologia
20.
Pharmacology ; 103(5-6): 320-323, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30889613

RESUMO

BACKGROUND: Nasal carriage of Staphylococcus aureus is very common among health care workers, and treatment with mupirocin is one of the choicest antibiotics available. But with the rampant usage of mupirocin like other antibiotics, the emergence of mupirocin resistance is also on rise. This resistance is both low level as well as high level among the isolated strains. AIM: To screen for the high-level mupirocin resistance among the isolated Staphylococcus strains by Kirby Bauer disk diffusion method. MATERIALS AND METHODS: A total of 200 clinical isolates were tested for high level mupirocin resistance by disk diffusion method using Himedia disks. RESULTS: Among the 200 nasal swabs, 26 (13%) showed growth of S. aureus, whereas 174 (87%) showed the growth of coagulase negative staphylococcus (CONS) spp. Mupirocin resistance was observed only among CONS spp, which was 15% for low-level mupirocin and 8% for high-level mupirocin resistance. No mupirocin resistance was observed among the Staphylococcus spp. CONCLUSION: The identification of Mupirocin resistance will guide us to utilize the antibiotic in a judicious way to treat the nasal carriage effectively.


Assuntos
Antibacterianos/farmacologia , Mupirocina/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus/efeitos dos fármacos , Antibacterianos/administração & dosagem , Portador Sadio/microbiologia , Estudos Transversais , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana , Feminino , Pessoal de Saúde , Humanos , Masculino , Mupirocina/administração & dosagem , Cavidade Nasal/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/enzimologia , Staphylococcus/isolamento & purificação
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