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1.
Medicine (Baltimore) ; 99(26): e20517, 2020 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-32590733

RESUMEN

Literature regarding the value of pre-operative nasal methicillin resistant Staphylococcus aureus (MRSA) swabs to predict surgical site infections (SSIs) in children undergoing lower extremity surgery is limited. The purpose of our study was to determine if pre-operative nasal MRSA swab results were predictive of SSI development in children undergoing a femoral varus derotational osteotomy (VDRO).Patients who underwent VDRO between 2004-2016 were reviewed to determine pre-operative MRSA colonization rates and SSI devolvement rates. Patients with less than 1 year of follow-up, previous history of infections, or absent pre-operative MRSA swab were excluded. SSI rates of patients with negative MRSA and positive MRSA swab result were compared using the Fisher exact test. Aside from contact isolation precautions, no other changes in treatment were made during inpatient hospital course based on positive pre-operative nasal MRSA swab results.247 patients met the inclusion criteria (mean age: 9.3 ±â€Š3.6 years, 62% male). There were 242 (98%) patients with a negative MRSA swab and 5 (2%) patients with a positive MRSA swab. Out of the 242 patients with a negative MRSA swab, 4 developed an SSI. Of the patients with positive MRSA swab results, 0% (0/5) developed an SSI compared to 1.7% (4/242) of negative MRSA swab results who developed an SSI. Results indicated no significant difference in SSI development rates between the groups (P = 1.00).In this series of children undergoing VDRO surgery, the results of a pre-operative MRSA nasal swab had no relationship to SSI incidence and no impact on clinical patient care. Pre-operative MRSA nasal swabs appear to be of limited benefit for routine pre-operative screening in this patient population.Level III, retrospective comparative.


Asunto(s)
Portador Sano , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Cavidad Nasal/microbiología , Osteotomía , Infección de la Herida Quirúrgica/epidemiología , Niño , Femenino , Fémur/cirugía , Estudios de Seguimiento , Humanos , Masculino , Cuidados Preoperatorios , Infecciones por Pseudomonas/epidemiología , Estudios Retrospectivos , Infecciones Estafilocócicas/epidemiología , Infección de la Herida Quirúrgica/microbiología
2.
R I Med J (2013) ; 103(2): 18-20, 2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-32122094

RESUMEN

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.


Asunto(s)
Antibacterianos/farmacología , Portador Sano/microbiología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Cavidad Nasal/microbiología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/aislamiento & purificación , Adulto , Antibacterianos/uso terapéutico , Portador Sano/epidemiología , Femenino , Humanos , Masculino , Resistencia a la Meticilina , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Cuidados Preoperatorios , Periodo Preoperatorio , Prevalencia , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/clasificación , Staphylococcus aureus/efectos de los fármacos
3.
BMC Vet Res ; 16(1): 28, 2020 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32000773

RESUMEN

BACKGROUND: Previous studies have shown that the genus Moraxella is commonly present in the nasal microbiota of swine. RESULTS: In this study, 51 isolates of Moraxella were obtained from nasal swabs from 3 to 4 week old piglets, which represented 26 different fingerprintings by enterobacterial repetitive intergenic consensus (ERIC)-PCR. Whole 16S rRNA gene sequencing allowed the identification at species level of the Moraxella spp. isolates. The majority of the field strains were identified as Moraxella pluranimalium, but Moraxella porci was also detected. In addition, a cluster of 7 strains did not group with any described Moraxella species, probably representing a new species. Subsequent phenotypic characterization indicated that strains of Moraxella pluranimalium were mainly sensitive to serum complement, while the cluster representing the putative new species was highly resistant. Biofilm formation capacity was very variable among the Moraxella spp. isolates, while adherence to epithelial cell lines was similar among selected strains. Additionally, variability was also observed in the association of selected strains to porcine alveolar macrophages. Antimicrobial tests evidenced the existence of multidrug-resistance in the strains. CONCLUSIONS: In summary, phenotypic characterization revealed heterogeneity among Moraxella strains from the nasal cavity of piglets. Strains with pathogenic potential were detected as well as those that may be commensal members of the nasal microbiota. However, the role of Moraxella in porcine diseases and health should be further evaluated.


Asunto(s)
Moraxella/aislamiento & purificación , Cavidad Nasal/microbiología , Porcinos/microbiología , Células A549 , Animales , Antiinfecciosos , Biopelículas , Línea Celular , Farmacorresistencia Bacteriana Múltiple , Humanos , Macrófagos Alveolares/microbiología , Moraxella/clasificación , Moraxella/genética , ARN Ribosómico 16S/genética
4.
Ann Otol Rhinol Laryngol ; 129(1): 5-11, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31390881

RESUMEN

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.


Asunto(s)
Antibacterianos/uso terapéutico , Profilaxis Antibiótica , Cavidad Nasal/microbiología , Tabique Nasal/cirugía , Procedimientos Quírurgicos Nasales/métodos , Férulas (Fijadores)/microbiología , Infección de la Herida Quirúrgica/prevención & control , Adolescente , Adulto , Anciano , Combinación Amoxicilina-Clavulanato de Potasio/uso terapéutico , Cefalexina/uso terapéutico , Técnicas de Cultivo , Farmacorresistencia Bacteriana , Farmacorresistencia Bacteriana Múltiple , Enterobacteriaceae/aislamiento & purificación , Infecciones por Enterobacteriaceae/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/aislamiento & purificación , Infección de la Herida Quirúrgica/epidemiología , Adulto Joven
5.
Cell Host Microbe ; 27(1): 68-78.e5, 2020 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-31866425

RESUMEN

The composition of the human microbiome profoundly impacts human well-being. However, the mechanisms underlying microbiome maturation are poorly understood. The nasal microbiome is of particular importance as a source of many respiratory infections. Here, we performed a large sequencing and culture-based analysis of the human nasal microbiota from different age groups. We observed a significant decline of pathogenic bacteria before adulthood, with an increase of the commensal Staphylococcus epidermidis. In seniors, this effect was partially reversed. In vitro, many S. epidermidis isolates stimulated nasal epithelia to produce antimicrobial peptides, killing pathogenic competitors, while S. epidermidis itself proved highly resistant owing to its exceptional capacity to form biofilms. Furthermore, S. epidermidis isolates with high antimicrobial peptide-inducing and biofilm-forming capacities outcompeted pathogenic bacteria during nasal colonization in vivo. Our study identifies a pivotal role of S. epidermidis in healthy maturation of the nasal microbiome, which is achieved at least in part by symbiotic cooperation with innate host defense.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/biosíntesis , Microbiota/inmunología , Cavidad Nasal/microbiología , Staphylococcus epidermidis , Adulto , Anciano de 80 o más Años , Biopelículas/crecimiento & desarrollo , Línea Celular , Niño , Preescolar , Células Epidérmicas , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Interacciones Microbiota-Huesped , Humanos , Inmunidad Innata , Masculino , Metagenómica , ARN Ribosómico 16S , Staphylococcus epidermidis/aislamiento & purificación , Staphylococcus epidermidis/metabolismo , Simbiosis , Adulto Joven
6.
Rheumatology (Oxford) ; 59(1): 77-83, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31834404

RESUMEN

OBJECTIVE: To identify the role of Staphylococcus aureus (SA) or its intracellular small-colony variant phenotype (SCV) with co-trimoxazole (CTX) or ANCA-associated vasculitis (AAV) activity. METHODS: All consecutive AAV patients with granulomatosis with polyangiitis (GPA), eosinophilic GPA or microscopic polyangiitis, followed at the French National Vasculitis Referral Center (09/2012-05/2013), and hospitalized non-AAV controls, exclusively for SA/SCV carriage comparisons, were enrolled. All had bilateral anterior nasal swab cultures. Nasal SA or SCV carriage was determined and associations with relapse(s), BVAS, ANCA-positivity, anti-staphylococcal and immunosuppressant use, were analysed ⩾4 years post-inclusion. RESULTS: Nasal SA carriage rates did not differ among AAVs (P = 0.53): GPA (24/80; 30%), EGPA (7/28; 25%) and microscopic polyangiitis (3/11; 27.3%); and the rate was less frequent in controls than in GPA patients not taking CTX (P = 0.04). AAV patients taking CTX prophylaxis had less nasal SA carriage (8.7% vs 36.2%; P = 0.02). Nasal SA carriage or CTX use did not modify relapse rates, BVAS or ANCA-positivity at inclusion or during follow-up. Nasal SCV carriage, found in 15/207 (7.2%) patients, was similar for GPA (10/24; 41.7%), microscopic polyangiitis (2/7; 28.6%) and eosinophilic GPA (2/3; 66.7%), but higher (P = 0.02) than controls (1/14; 7.1%). SCV carriage by AAV groups did not modify relapse rates or ANCA positivity at inclusion or during follow-up; a trend towards higher BVAS was observed only for anti-PR3 ANCA patients. CONCLUSION: Nasal SA or SCV carriage was comparable among AAVs but more frequent than in controls. Nasal SA or SCV carriage and CTX use did not modify AAV relapse rates.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/microbiología , Profilaxis Antibiótica/métodos , Prevención Secundaria/métodos , Staphylococcus aureus/crecimiento & desarrollo , Combinación Trimetoprim y Sulfametoxazol/administración & dosificación , Adulto , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/tratamiento farmacológico , Síndrome de Churg-Strauss/tratamiento farmacológico , Síndrome de Churg-Strauss/microbiología , Femenino , Francia , Granulomatosis con Poliangitis/tratamiento farmacológico , Granulomatosis con Poliangitis/microbiología , Humanos , Masculino , Poliangitis Microscópica/tratamiento farmacológico , Poliangitis Microscópica/microbiología , Persona de Mediana Edad , Cavidad Nasal/microbiología , Fenotipo , Estudios Prospectivos , Recurrencia , Infecciones Estafilocócicas/prevención & control , Resultado del Tratamiento
8.
BMC Infect Dis ; 19(1): 899, 2019 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-31660878

RESUMEN

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.


Asunto(s)
Resistencia a la Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/genética , Cavidad Nasal/microbiología , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Adolescente , Adulto , Anciano , Toxinas Bacterianas/genética , Niño , Preescolar , Estudios Transversales , Exotoxinas/genética , Femenino , Frecuencia de los Genes , Humanos , Lactante , Irán/epidemiología , Leucocidinas/genética , Masculino , Tamizaje Masivo , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Prevalencia , Salud Pública , Factores de Riesgo , Adulto Joven
10.
BMC Infect Dis ; 19(1): 753, 2019 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-31462296

RESUMEN

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.


Asunto(s)
Lepra/microbiología , Mycobacterium leprae/genética , Cavidad Nasal/microbiología , ARN Ribosómico 16S , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , ADN Bacteriano/genética , Humanos , Lepra/diagnóstico , Lepra Multibacilar/diagnóstico , Lepra Multibacilar/microbiología , Persona de Mediana Edad , Mycobacterium leprae/aislamiento & purificación , Mycobacterium leprae/patogenicidad , ARN Ribosómico 16S/genética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Togo , Adulto Joven
11.
Mymensingh Med J ; 28(3): 627-633, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31391436

RESUMEN

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.


Asunto(s)
Personal de Salud , Staphylococcus aureus Resistente a Meticilina , Cavidad Nasal , Infecciones Estafilocócicas , Antibacterianos , Bangladesh , Estudios Transversales , Humanos , Meticilina , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Cavidad Nasal/microbiología , Infecciones Estafilocócicas/diagnóstico , Staphylococcus aureus , Centros de Atención Terciaria
12.
Eur J Clin Microbiol Infect Dis ; 38(11): 2037-2044, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31332610

RESUMEN

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.


Asunto(s)
Portador Sano/epidemiología , Personas sin Hogar/estadística & datos numéricos , Cavidad Nasal/microbiología , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/aislamiento & purificación , Adulto , Antibacterianos/farmacología , Técnicas de Tipificación Bacteriana , Portador Sano/microbiología , Farmacorresistencia Bacteriana/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Femenino , Humanos , Masculino , Staphylococcus aureus Resistente a Meticilina/clasificación , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Portugal/epidemiología , Prevalencia , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/clasificación , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/genética
13.
PLoS One ; 14(7): e0218511, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31276521

RESUMEN

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.


Asunto(s)
Conducta Anticonceptiva , Anticonceptivos Hormonales Orales/administración & dosificación , Estrógenos , Cavidad Nasal/microbiología , Faringe/microbiología , Progestinas , Staphylococcus aureus , Adolescente , Adulto , Estrógenos/administración & dosificación , Estrógenos/efectos adversos , Femenino , Humanos , Noruega/epidemiología , Prevalencia , Progestinas/administración & dosificación , Progestinas/efectos adversos , Factores de Riesgo , Infecciones Estafilocócicas/inducido químicamente , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus aureus/aislamiento & purificación , Adulto Joven
14.
Int J Syst Evol Microbiol ; 69(9): 2928-2935, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31310200

RESUMEN

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.


Asunto(s)
Aves/microbiología , Corynebacterium/clasificación , Cavidad Nasal/microbiología , Filogenia , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , Corynebacterium/aislamiento & purificación , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Genes Bacterianos , Hibridación de Ácido Nucleico , Peptidoglicano/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
15.
Ann N Y Acad Sci ; 1449(1): 3-24, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31180143

RESUMEN

Microorganisms resident in our bodies participate in a variety of regulatory and pathogenic processes. Here, we describe how etiological pathways implicated in Alzheimer's disease (AD) may be regulated or disturbed by symbiotic microbial activity. Furthermore, the composition of symbiotic microbes has changed dramatically across human history alongside the rise of agriculturalism, industrialization, and globalization. We postulate that each of these lifestyle transitions engendered progressive depletion of microbial diversity and enhancement of virulence, thereby enhancing AD risk pathways. It is likely that the human life span extended into the eighth decade tens of thousands of years ago, yet little is known about premodern geriatric epidemiology. We propose that microbiota of the gut, oral cavity, nasal cavity, and brain may modulate AD pathogenesis, and that changes in the microbial composition of these body regions across history suggest escalation of AD risk. Dysbiosis may promote immunoregulatory dysfunction due to inadequate education of the immune system, chronic inflammation, and epithelial barrier permeability. Subsequently, proinflammatory agents-and occasionally microbes-may infiltrate the brain and promote AD pathogenic processes. APOE genotypes appear to moderate the effect of dysbiosis on AD risk. Elucidating the effect of symbiotic microbiota on AD pathogenesis could contribute to basic and translational research.


Asunto(s)
Enfermedad de Alzheimer/microbiología , Enfermedad de Alzheimer/patología , Microbioma Gastrointestinal/fisiología , Envejecimiento/fisiología , Evolución Biológica , Encéfalo/microbiología , Disbiosis/inmunología , Disbiosis/microbiología , Humanos , Inflamación/inmunología , Inflamación/microbiología , Boca/microbiología , Cavidad Nasal/microbiología , Simbiosis/fisiología
16.
Artículo en Inglés | MEDLINE | ID: mdl-31165051

RESUMEN

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.


Asunto(s)
Células Epiteliales/microbiología , Microbiota , Cavidad Nasal/microbiología , Mucosa Nasal/microbiología , Bacterias , Línea Celular , Células Inmovilizadas , Técnicas de Cultivo , Ecosistema , Células Epiteliales/inmunología , Femenino , Humanos , Masculino , Interacciones Microbianas , Cavidad Nasal/inmunología , Mucosa Nasal/inmunología , Texas , Voluntarios
17.
Pathog Dis ; 77(3)2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-31247637

RESUMEN

Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) clones other than Clonal Complex (CC)398, as CC1, have been isolated in pigs in some countries, and appeared to be prevalent in Italy. The aim of this study was to evaluate the capability of Sequence Type (ST)1, CC1, LA-MRSA clone to colonize and to be transmitted among piglets. Eighteen caesarean-derived/colostrum-deprived piglets of 35 days of age were assigned randomly to three groups: four seeder piglets were contaminated with a spa type t127, ST1, SCCmec V, MRSA (Group A), 10 MRSA-negative piglets were exposed to Group A after 2 days post-contamination, dpc (Group B) and 4 piglets were used as control group (Group C). Piglets were evaluated until 44 dpc (Group A) or at 42 days post-exposure, dpe (Group B) and then euthanized and necropsied. All nasal and skin cultures of Group A resulted MRSA-positive throughout the experiment starting from two dpc, while Group C tested always MRSA-negative. At first sampling, all Group B piglets became positive and remained positive throughout the experiment. This is the first colonization/transmission study with a CC1 LA-MRSA in pigs. The results add further knowledge on the ability of CC1 LA-MRSA to colonize pigs, and on colonization/transmission patterns, both suggesting good host adaptation.


Asunto(s)
Portador Sano/microbiología , Portador Sano/transmisión , Transmisión de Enfermedad Infecciosa , Genotipo , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Estafilocócicas/veterinaria , Porcinos/microbiología , Animales , Italia , Staphylococcus aureus Resistente a Meticilina/clasificación , Staphylococcus aureus Resistente a Meticilina/genética , Tipificación de Secuencias Multilocus , Cavidad Nasal/microbiología , Piel/microbiología , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/transmisión
18.
BMC Infect Dis ; 19(1): 478, 2019 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-31142269

RESUMEN

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.


Asunto(s)
Farmacorresistencia Bacteriana , Infecciones por Bacterias Grampositivas/diagnóstico , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Niño , Preescolar , Estudios Transversales , Farmacorresistencia Bacteriana/efectos de los fármacos , Femenino , Infecciones por Bacterias Grampositivas/microbiología , Humanos , Masculino , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Cavidad Nasal/microbiología , Factores de Riesgo , Factores Socioeconómicos , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/genética , Staphylococcus aureus/aislamiento & purificación , Streptococcus/efectos de los fármacos , Streptococcus/genética , Streptococcus/aislamiento & purificación
19.
J Anim Sci ; 97(6): 2368-2375, 2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-31144716

RESUMEN

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.


Asunto(s)
Bacterias/clasificación , Enfermedades de los Bovinos/epidemiología , Bovinos/microbiología , Microbiota , Infecciones del Sistema Respiratorio/veterinaria , Animales , Bacterias/genética , Biodiversidad , Enfermedades de los Bovinos/microbiología , Secuenciación de Nucleótidos de Alto Rendimiento/veterinaria , Incidencia , Cavidad Nasal/microbiología , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/microbiología , Análisis de Secuencia de ADN , Simbiosis , Estados Unidos/epidemiología , Destete
20.
Medicine (Baltimore) ; 98(18): e15499, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31045837

RESUMEN

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.


Asunto(s)
Homocisteína/sangre , Staphylococcus aureus Resistente a Meticilina/crecimiento & desarrollo , Cavidad Nasal/microbiología , Infecciones Estafilocócicas/sangre , Adulto , Anciano , Anciano de 80 o más Años , Recuento de Colonia Microbiana , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Oportunidad Relativa , Prevalencia , Factores de Riesgo , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Estados Unidos/epidemiología , Adulto Joven
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