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OBJECTIVES: MDR bacteria have become a prevailing health threat worldwide. We here aimed to use optical DNA mapping (ODM) as a rapid method to trace nosocomial spread of bacterial clones and gene elements. We believe that this method has the potential to be a tool of pivotal importance for MDR control. METHODS: Twenty-four Escherichia coli samples of ST410 from three different wards were collected at an Ethiopian hospital and their plasmids were analysed by ODM. Plasmids were specifically digested with Cas9 targeting the antibiotic resistance genes, stained by competitive binding and confined in nanochannels for imaging. The resulting intensity profiles (barcodes) for each plasmid were compared to identify potential clonal spread of resistant bacteria. RESULTS: ODM demonstrated that a large fraction of the patients carried bacteria with a plasmid of the same origin, carrying the ESBL gene blaCTX-M-15, suggesting clonal spread. The results correlate perfectly with core genome (cg)MLST data, where bacteria with the same plasmid also had very similar cgMLST profiles. CONCLUSIONS: ODM is a rapid discriminatory method for identifying plasmids and antibiotic resistance genes. Long-range deletions/insertions, which are challenging for short-read next-generation sequencing, can be easily identified and used to trace bacterial clonal spread. We propose that plasmid typing can be a useful tool to identify clonal spread of MDR bacteria. Furthermore, the simplicity of the method enables possible future application in low- and middle-income countries.
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Surtos de Doenças , Infecções por Escherichia coli , Plasmídeos , Antibacterianos/farmacologia , Criança , Infecções por Escherichia coli/epidemiologia , Hospitais , Humanos , Lactente , Tipagem de Sequências Multilocus , beta-Lactamases/genéticaRESUMO
BACKGROUND: Wound infection is one of the health problems that are caused and aggravated by the invasion of pathogenic organisms. Information on local pathogens and sensitivity to antimicrobial agents, and topical agents like acetic acid is crucial for successful treatment of wounds. OBJECTIVES: To determine antimicrobial susceptibility pattern of bacterial isolates from wound infection and their sensitivity to alternative topical agents at Jimma University Specialized Hospital. METHODS: A cross sectional study was conducted among patients with wound infection visiting Jimma University Specialized Hospital, from May to September 2013. Wound swab was collected using sterile cotton swabs and processed for bacterial isolation and susceptibility testing to antimicrobial agents, acetic acid, hydrogen peroxide and dabkin solution following standard bacteriological techniques. Biochemical tests were done to identify the species of the organisms. Sensitivity testing was done using Kirby- Baur disk diffusion method. Minimum inhibitory and bactericidal concentration was done using tube dilution method. RESULTS: In this study 145 bacterial isolates were recovered from 150 specimens showing an isolation rate of 87.3%. The predominant bacteria isolated from the infected wounds were Staphylococcus aureus 47 (32.4%) followed by Escherichia coli 29 (20%), Proteus species 23 (16%), Coagulase negative Staphylococci 21 (14.5%), Klebsiella pneumoniae 14 (10%) and Pseudomonas aeruginosa 11 (8%). All isolates showed high frequency of resistance to ampicillin, penicillin, cephalothin and tetracycline. The overall multiple drug resistance patterns were found to be 85%. Acetic acid (0.5%), Dabkin solution (1%) and 3% hydrogen peroxide were bactericidal to all isolated bacteria and lethal effect observed when applied for 10 minutes. CONCLUSIONS: On in vitro sensitivity testing, ampicillin, penicillin, cephalothin and tetracycline were the least effective. Gentamicin, norfloxacin, ciprofloxacin, vancomycin and amikacin were the most effective antibiotics. Acetic acid (0.5%), dabkin solution (1%) and H2O2 (3%) were bactericidal to all isolates.
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Antibacterianos/farmacologia , Anti-Infecciosos Locais/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/microbiologia , Infecção dos Ferimentos/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bactérias/isolamento & purificação , Criança , Pré-Escolar , Estudos Transversais , Etiópia , Feminino , Hospitais Universitários , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Antimicrobials cause perturbations in the composition and diversity of the host microbiome. We aimed to compare gut microbiome perturbations caused by oral tebipenem pivoxil hydrobromide (a novel carbapenem) and by amoxicillin-clavulanic acid (an orally administered ß-lactam-ß-lactam inhibitor combination widely used in clinical practice). METHODS: We did a phase 1, single-centre, randomised, parallel-group, active-control trial to evaluate the effect of tebipenem pivoxil hydrobromide on the human gut microbiota. Healthy participants aged 18 years or older with no documented illnesses during recruitment were enrolled at Karolinska University Hospital (Stockholm, Sweden). Study participants were stratified by sex and block-randomised in a 1:1 ratio to treatment with either tebipenem pivoxil hydrobromide (600 mg orally every 8 h) or amoxicillin-clavulanic acid (500 mg amoxicillin and 125 mg clavulanic acid orally every 8 h). The study included 10 days of treatment (days 1-10) and four follow-up visits (days 14, 21, 90, and 180). The trial was open-label for clinical investigators and patients, but masked for microbiology investigators. Faecal samples were collected at all visits. Sequencing of 16S rDNA was used to measure the diversity metrics, and quantitative culture to quantify selected taxa. The primary outcomes were changes in the α and ß diversity and log count of colony-forming units for selected taxa between samples compared with baseline (day 1), and whether any changes reverted during the follow-up period. The analyses were done in the intention-to-treat population. This study was registered with ClinicalTrials.gov (NCT04376554). FINDINGS: The study was conducted between Jan 23, 2020, and April 6, 2021. 49 volunteers were screened for eligibility, among whom 30 evaluable participants (14 men and 16 women) were assigned: 15 (50%) to the tebipenem pivoxil hydrobromide group and 15 (50%) to the amoxicillin-clavulanic acid group. Baseline characteristics were similar between groups. Complete follow-up was available for all participants, and all participants except one completed treatment as assigned. The diversity metrics showed significant changes from baseline during the treatment period. Significant decreases in richness were observed on days 4-10 (p≤0·0011) in the amoxicillin-clavulanic acid group and on days 4-14 (p≤0·0019) in the tebipenem pivoxil hydrobromide group. Similarly, evenness was significantly decreased during treatment in the amoxicillin-clavulanic acid group (day 4, p=0·030) and the tebipenem pivoxil hydrobromide group (days 4-10, p<0·0001) compared with baseline. Quantitative cultures showed significant decreases in Enterobacterales (days 4-7, p≤0·0030), Enterococcus spp (days 4-14, p=0·025 to p<0·0001), Bifidobacterium spp (days 2-4, p≤0·026), and Bacteroides spp (days 4-10, p≤0·030) in the tebipenem pivoxil hydrobromide group. Similarly, in amoxicillin-clavulanic acid recipients, significant changes were observed in Enterobacterales (days 4-10, p≤0·048), Bifidobacterium spp (days 2-4, p≤0·013), and Lactobacillus spp (days 2-4, p≤0·020). Samples from the follow-up period were not significantly different from those at baseline in ß diversity analysis (PERMANOVA, p>0·99). By the end of the study, no significant change was observed compared with baseline in either group. There were no deaths or severe adverse events. INTERPRETATION: The impact of tebipenem pivoxil hydrobromide on the gut microbiome was similar to that of amoxicillin-clavulanic acid. The safety of antibiotic use with regard to the microbiome should be given attention, as dysbiosis is associated with health and disease. FUNDING: Spero Therapeutics.
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Carbapenêmicos , Microbioma Gastrointestinal , Masculino , Adulto , Humanos , Feminino , Combinação Amoxicilina e Clavulanato de Potássio/farmacologia , Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Suécia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , MonobactamasRESUMO
INTRODUCTION: Hospital acquired infections are recognized as critical public health problems. Infections are frequently caused by organisms residing in healthcare environment, including contaminated medical equipment like Stethoscopes. OBJECTIVE: To determine bacterial contamination, bacterial profile and anti-microbial susceptibility pattern of the isolates from stethoscopes at Jimma University Specialized Hospital. METHODOLOGY: Cross-sectional study conducted from May to September 2011 at Jimma University Specialized Hospital. One hundred seventy-six stethoscopes owned by Health Care Workers (HCWs) and Medical students were randomly selected and studied. Self-administered structured questionnaire was used to collect socio-demographic data. Specimen was collected using moisten sterile cotton swab and 1 ml normal saline was used to transport the specimen, all laboratory investigations were done following standard microbiological techniques, at Microbiology Laboratory, Jimma University. SPSS windows version 16 used for data analysis and P <0.05 was considered statistically significant. RESULT: A total, of 151 (85.8%) stethoscopes were contaminated. A total of 256 bacterial strains and a mean of 1.44×104 CFUs/diaphragm of stethoscopes was isolated. Of the 256 isolates, 133 (52%) were potential pathogens like S. aureus, Klebsiella spp., Citrobacter spp., Salmonella spp., Proteus spp., Enterobacter spp., P. aeruginosa and E. coli. All strains were resistant to multiple classes of antibiotics (two to eight classes of antibiotics). Disinfection practice was poor. Disinfection practice was found to be associated with bacterial contamination of stethoscopes (P < 0.05). High contamination rate 100 (90.9%) was observed among stethoscopes that had never been disinfected; while the least contamination 29 (72.2%) was found on those disinfected a week or less before the survey. CONCLUSION: Bacterial contamination of the stethoscope was significant. The isolates were potential pathogens and resistant to multiple classes of antibiotics. Stethoscope is potential vehicle in the transmission of infections between patients and Healthcare Workers. Stethoscope diaphragm should be disinfected before and after each patient contact.
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Bactérias/classificação , Bactérias/isolamento & purificação , Estetoscópios/microbiologia , Biodiversidade , Contagem de Colônia Microbiana , Estudos Transversais , Etiópia , Hospitais Universitários , Humanos , Testes de Sensibilidade MicrobianaRESUMO
Objectives: Colistin is a last-resort antibiotic, but there has been a rapid increase in colistin resistance, threatening its use in the treatment of infections with carbapenem-resistant Enterobacterales (CRE). Plasmid-mediated colistin resistance, in particular the mcr-1 gene, has been identified and WGS is the go-to method in identifying plasmids carrying mcr-1 genes. The goal of this study is to demonstrate the use of optical DNA mapping (ODM), a fast, efficient and amplification-free technique, to characterize plasmids carrying mcr-1. Methods: ODM is a single-molecule technique, which we have demonstrated can be used for identifying plasmids harbouring antibiotic resistance genes. We here applied the technique to plasmids isolated from 12 clinical Enterobacterales isolates from patients at a major hospital in Thailand and verified our results using Nanopore long-read sequencing. Results: We successfully identified plasmids encoding the mcr-1 gene and, for the first time, demonstrated the ability of ODM to identify resistance gene sites in small (â¼30â kb) plasmids. We further identified bla CTX-M genes in different plasmids than the ones encoding mcr-1 in three of the isolates studied. Finally, we propose a cut-and-stretch assay, based on similar principles, but performed using surface-functionalized cover slips for DNA immobilization and an inexpensive microscope with basic functionalities, to identify the mcr-1 gene in a plasmid sample. Conclusions: Both ODM and the cut-and-stretch assay developed could be very useful in identifying plasmids encoding antibiotic resistance in hospitals and healthcare facilities. The cut-and-stretch assay is particularly useful in low- and middle-income countries, where existing techniques are limited.
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BACKGROUND: Identification of pathogens is crucial to efficiently treat and prevent bacterial infections. However, existing diagnostic techniques are slow or have a too low resolution for well-informed clinical decisions. METHODS: In this study, we have developed an optical DNA mapping-based method for strain-level bacterial typing and simultaneous plasmid characterisation. For the typing, different taxonomical resolutions were examined and cultivated pure Escherichia coli and Klebsiella pneumoniae samples were used for parameter optimization. Finally, the method was applied to mixed bacterial samples and uncultured urine samples from patients with urinary tract infections. RESULTS: We demonstrate that optical DNA mapping of single DNA molecules can identify Escherichia coli and Klebsiella pneumoniae at the strain level directly from patient samples. At a taxonomic resolution corresponding to E. coli sequence type 131 and K. pneumoniae clonal complex 258 forming distinct groups, the average true positive prediction rates are 94% and 89%, respectively. The single-molecule aspect of the method enables us to identify multiple E. coli strains in polymicrobial samples. Furthermore, by targeting plasmid-borne antibiotic resistance genes with Cas9 restriction, we simultaneously identify the strain or subtype and characterize the corresponding plasmids. CONCLUSION: The optical DNA mapping method is accurate and directly applicable to polymicrobial and clinical samples without cultivation. Hence, it has the potential to rapidly provide comprehensive diagnostics information, thereby optimizing early antibiotic treatment and opening up for future precision medicine management.
For bacterial infections, it is important to rapidly and accurately identify and characterize the type of bacteria involved so that optimal antibiotic treatment can be given quickly to the patient. However, current diagnostic methods are sometimes slow and cannot be used for mixtures of bacteria. We have, therefore, developed a method to identify bacteria directly from patient samples. The method was tested on two common species of disease-causing bacteria Escherichia coli and Klebsiella pneumoniae and it could correctly identify the bacterial strain or subtype in both urine samples and mixtures. Hence, the method has the potential to provide fast diagnostic information for choosing the most suited antibiotic, thereby reducing the risk of death and suffering.
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Introduction: Pseudomonas aeruginosa (P. aeruginosa) and Acinetobacter baumannii (A. baumannii) can cause difficult-to-treat infections. We characterized molecular epidemiology of ceftazidime-resistant P. aeruginosa and carbapenem-resistant A. baumannii at a tertiary hospital in Ethiopia. Materials and methods: Non-fermenting gram-negative bacilli (n = 80) isolated from admitted patients were subjected for species identification by MALDI-TOF. Pseudomonas species resistant to ceftazidime or meropenem, and Acinetobacter species resistant to meropenem, or imipenem were selected for whole genome sequencing. DNA extracted with EZ1 Advanced XL instrument (Qiagen, Hilden, Germany) was sequenced on Illumina (HiSeq2500) using libraries prepared by NEXTRA-kits (Illumina). Raw reads were assembled using SPAdes 3.13.0, and assembled genomes were used to query databases for resistome profile and sequence types. Result: Among Pseudomonas species isolated, 31.7% (13/41), and 7.3% (3/41) were non-susceptible to ceftazidime, and meropenem, respectively. Carbapenem-resistance was 56.4% (22/39) among Acinetobacter species. Moreover, 92% (12/13) of Pseudomonas species non-susceptible to ceftazidime and/or meropenem, and 89.4% (17/19) of Acinetobacter species encoded multiple resistance genes for at least three classes of antimicrobials. The prevalent ß - lactamase genes were bla OXA-486 (53.8%, 7/13), bla CTX-M-15 (23.0%, 3/13) among Pseudomonas, and bla GES-11 (57.8%, 11/19) among Acinetobacter. The bla OXA-51-like ß - lactamase, bla OXA-69 (63.1%, 12/19) was the most prevalent carbapenemase gene among Acinetobacter isolates. Single isolates from both P. aeruginosa, and A. baumannii were detected with the bla NDM-1. Sequence type (ST)1 A. baumannii and ST274 P. aeruginosa were the prevalent sequence types. A cgMLST analysis of the ST1 A. baumannii isolates showed that they were closely related and belonged to the international clonal complex one (ICC1). Similarly, ST274 P. aeruginosa isolates were clonally related. Conclusion: The prevalence of MDR isolates of Pseudomonas and Acinetobacter spp. was high. A. baumannii isolates were clonally spreading in the admission wards at the hospital. Emergence of bla NDM-1 in the intensive care, and surgical wards of the hospital is a severe threat that requires urgent intervention.
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OBJECTIVES: The burden of antimicrobial resistance and spread of epidemic clones are rarely reported from low-income countries. We aimed to investigate the genome-based epidemiology of extended-spectrum ß-lactamase-producing Escherichia coli (ESBL-EC) at a tertiary hospital in Jimma, Ethiopia. METHODS: Bacteria were isolated from clinical specimens at Jimma Medical Center and subjected to species identification (MALDI-TOF), antimicrobial susceptibility testing (disk diffusion) and whole-genome sequencing (Illumina, HiSeq2500). Genomic data analysis was performed using EnteroBase and Center for Genomic Epidemiology bioinformatics pipelines. A maximum likelihood tree was generated using FastTree/2.1.8 based on single nucleotide polymorphisms (SNPs) in shared genomic regions to identify transmission clusters. RESULTS: Escherichia coli isolates (n = 261) were collected from 1087 single non-duplicate clinical specimens over a 5-month period in 2016. The prevalence of ESBL-EC was 54.8% (143/261), 96% of which were resistant to multiple antibiotic classes. The blaCTX-M-15 ESBL gene was present in 88.4.% of isolates (122/138). Genes conferring resistance to aminoglycosides and ciprofloxacin [aac(6')-Ib-cr, 62.3% (86/138)], phenicols [catB3, 56.5% (78/138)], sulfonamides [sul1, 68.1% (94/138), trimethoprim [dfrA17, 58.0% (80/138)] and macrolides [mph(A), 67.4% (93/138) were detected. The most prevalent sequence types were ST410 (23%), ST648 (17%), ST131 (10%) and ST167 (7%). Isolates of the same sequence type collected from different units of the hospital were highly similar in the SNP analysis. CONCLUSION: A high prevalence of ESBLs and dissemination of blaCTX-M-15 through multiple high-risk E. coli clones was detected. Nosocomial spread of multidrug-resistant ESBL-EC within the hospital puts vulnerable patients at risk of difficult-to-treat infections.
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Infecções por Escherichia coli , Escherichia coli , Antibacterianos/farmacologia , Células Clonais , Infecções por Escherichia coli/microbiologia , Etiópia/epidemiologia , Humanos , Centros de Atenção Terciária , beta-Lactamases/genéticaRESUMO
Antimicrobial resistance (AMR) is a fast-growing threat to global health. The genes conferring AMR to bacteria are often located on plasmids, circular extrachromosomal DNA molecules that can be transferred between bacterial strains and species. Therefore, effective methods to characterize bacterial plasmids and detect the presence of resistance genes can assist in managing AMR, for example, during outbreaks in hospitals. However, existing methods for plasmid analysis either provide limited information or are expensive and challenging to implement in low-resource settings. Herein, we present a simple assay based on CRISPR/Cas9 excision and DNA combing to detect antimicrobial resistance genes on bacterial plasmids. Cas9 recognizes the gene of interest and makes a double-stranded DNA cut, causing the circular plasmid to linearize. The change in plasmid configuration from circular to linear, and hence the presence of the AMR gene, is detected by stretching the plasmids on a glass surface and visualizing by fluorescence microscopy. This single-molecule imaging based assay is inexpensive, fast, and in addition to detecting the presence of AMR genes, it provides detailed information on the number and size of plasmids in the sample. We demonstrate the detection of several ß-lactamase-encoding genes on plasmids isolated from clinical samples. Furthermore, we demonstrate that the assay can be performed using standard microbiology and clinical laboratory equipment, making it suitable for low-resource settings.
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Antibacterianos , Imagem Individual de Molécula , Antibacterianos/farmacologia , Bactérias/genética , Farmacorresistência Bacteriana/genética , Microscopia de Fluorescência , Plasmídeos/genéticaRESUMO
OBJECTIVES: Carbapenemase-producing Enterobacterales (CPE) are high priority targets of global antimicrobial surveillance. Herein, we determined the colonization rate of CPE on admission to intensive care units in Vientiane, Lao PDR in August-September 2019. METHODS: Data regarding clinical conditions, infection control, and antibiotic usage were collected during admission. Rectal swab samples (n = 137) collected during admission were inoculated to selective chromogenic agars, followed by confirmatory tests for extended-spectrum beta-lactamases and carbapenemases. All CPE isolates were sequenced on Illumina (HiSeq2500), reads assembled using SPAdes 3.13, and the draft genomes used to query a database (https://www.genomicepidemiology.org) for resistome, plasmid replicons, and sequence types (ST). Optical DNA mapping (ODM) was used to characterize plasmids and to determine location of resistance genes. Minimum spanning tree was generated using the Bacterial Isolate Genome Sequence database (BIGSdb) and annotated using iTOL. RESULT: From 47 Enterobacterales isolated on selective agars, K. pneumoniae (25/47) and E. coli (12/47) were the most prevalent species, followed by K aerogenes (2/47), K. variicola (1/47), and K. oxytoca (1/47). The overall prevalence of ESBLs was 51.0%; E. coli 83.3% (10/12) and Klebsiella spp. 41.3% (12/29). Twenty percent of the K. pneumoniae (5/25) isolates were carbapenem-resistant, and 4/5 contained the blaNDM-1 gene. All blaNDM-1 isolates belonged to ST147 and were indistinguishable with cgMLST. ODM showed that the blaNDM-1 gene was located on identical plasmids in all isolates. CONCLUSION: The prevalence of ESBL-producing Enterobacterales was high, while carbapenemases were less common. However, the detection of clonal dissemination of blaNDM-1-producing K. pneumoniae isolates in one of the intensive care units calls for vigilance. Stringent infection prevention and antimicrobial stewardship strategies are highly important measures.
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Infecções por Klebsiella , Klebsiella pneumoniae , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Proteínas de Bactérias/uso terapêutico , Carbapenêmicos/uso terapêutico , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli/genética , Humanos , Unidades de Terapia Intensiva , Infecções por Klebsiella/microbiologia , Laos , Testes de Sensibilidade Microbiana , Plasmídeos/genética , beta-Lactamases/genética , beta-Lactamases/uso terapêuticoRESUMO
OBJECTIVES: The carbapenemase-encoding gene blaNDM-1 has been reported in Vietnam during the last 10 years, and blaNDM-producing Enterobacteriaceae are now silently and rapidly spreading. A key factor behind dissemination of blaNDM-1 is plasmids, mobile genetic elements that commonly carry antibiotic resistance genes and spread via conjugation. The diversity of blaNDM-1-encoding plasmids from neonates at a large Vietnamese hospital was characterized in this study. METHODS: 18 fecal Klebsiella pneumoniae and Klebsiella quasipneumoniae isolates collected from 16 neonates at a large pediatric hospital in Vietnam were studied using optical DNA mapping (ODM) and next-generation sequencing (NGS). Plasmids carrying the blaNDM-1 gene were identified by combining ODM with Cas9 restriction. The plasmids in the isolates were compared to investigate whether the same plasmid was present in different patients. RESULTS: Although the same plasmid was found in some isolates, ODM confirmed that there were at least 10 different plasmids encoding blaNDM-1 among the 18 isolates, thus indicating wide plasmid diversity. The ODM results concur with the NGS data. Interestingly, some isolates had two distinct plasmids encoding blaNDM-1 that could be readily identified with ODM. The coexistence of different plasmids carrying the same blaNDM-1 gene in a single isolate has rarely been reported, probably because of limitations in plasmid characterization techniques. CONCLUSIONS: The plasmids encoding the blaNDM-1 gene in this study cohort were diverse and may represent a similar picture in Vietnamese society. The study highlights important aspects of the usefulness of ODM for plasmid analysis.
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Infecções por Klebsiella , Klebsiella pneumoniae , Antibacterianos/farmacologia , Povo Asiático , Hospitais , Humanos , Recém-Nascido , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Vietnã , beta-Lactamases/genéticaRESUMO
BACKGROUND: Genomic epidemiology of antibiotic resistance is not sufficiently studied in low-income countries. OBJECTIVES: To determine prevalence of ESBL production, and resistome and virulome profiles, of Klebsiella pneumoniae isolated at Jimma Medical Center, Ethiopia. METHODS: Strains isolated from patients with suspected infections between June and November 2016 were characterized by MALDI-TOF for species identification and disc diffusion for antimicrobial susceptibility testing. All K. pneumoniae isolates were characterized by double disc diffusion for ESBL production and all ESBL-producing strains (ESBL-KP) were subjected to WGS on the Illumina (HiSeq 2500) platform. DNA was extracted by automated systems (MagNA Pure 96). Genome assembly was performed using SPAdes (v. 3.9) and draft genomes were used for analysing molecular features of the strains. Maximum likelihood trees were generated using FastTree/2.1.8 based on SNPs in shared genomic regions to identify transmission clusters. RESULTS: Of the 146 K. pneumoniae strains isolated, 76% were ESBL-KP; 93% of the ESBL-KP strains showed resistance to multiple antimicrobial classes. bla CTX-M-15 (84.4%) was the most prevalent ESBL gene. Resistance genes for aminoglycosides and/or fluoroquinolones [aac(6')-Ib-cr (65.1%)], phenicols [catB3 (28.4%)], sulphonamides [sul1 (61.2%) and sul2 (60.5%)], trimethoprim [dfrA27 (32.1%)], macrolides [mph(A) (12.8%)] and rifampicin [arr2/arr3 (39.4%)] were prevalent. Plasmids of the IncF and IncR families were prevalent among ST218, ST147, ST15 and ST39. KL64 and KL57 capsular types and O1 and O2 LPSs were prevalent. A high-risk clone, ST218-KL57 encoding rmpA1/rmpA2 and iutA, was detected. Phylogenetic analysis showed a cluster of clonally related strains from different units of the hospital. CONCLUSIONS: Prevalence of ESBL-KP was high and bla CTX-M-15 was the predominant ESBL gene. ESBL genes had spread through both clonal and polyclonal expansion of high-risk and hypervirulent clones. Nosocomial transmission of MDR strains between different units of the hospital was observed.
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Carbapenem-resistant Klebsiella pneumoniae (CR-KP) in patients admitted to hospitals pose a great challenge to treatment. The genes causing resistance to carbapenems are mostly found in plasmids, mobile genetic elements that can spread easily to other bacterial strains, thus exacerbating the problem. Here, we studied 27 CR-KP isolates collected from different types of samples from 16 patients admitted to the medical ward at Siriraj Hospital in Bangkok, Thailand, using next generation sequencing (NGS) and optical DNA mapping (ODM). The majority of the isolates belonged to sequence type (ST) 16 and are described in detail herein. Using ODM, we identified the plasmid carrying the blaNDM-1 gene in the ST16 isolates and the plasmids were very similar, highlighting the possibility of using ODM of plasmids as a surrogate marker of nosocomial spread of bacteria. We also demonstrated that ODM could identify that the blaCTX-M-15 and blaOXA-232 genes in the ST16 isolates were encoded on separate plasmids from the blaNDM-1 gene and from each other. The other three isolates belonged to ST147 and each of them had distinct plasmids encoding blaNDM-1.
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Optical DNA mapping (ODM) has developed into an important technique for DNA analysis, where single DNA molecules are sequence-specifically labeled and stretched, for example, in nanofluidic channels. We have developed an ODM assay to analyze bacterial plasmids-circular extrachromosomal DNA that often carry genes that make bacteria resistant to antibiotics. As for most techniques, the next important step is to increase throughput and automation. In this work, we designed and fabricated a nanofluidic device that, together with a simple automation routine, allows parallel analysis of up to 10 samples at the same time. Using plasmids encoding extended-spectrum beta-lactamases (ESBL), isolated from Escherichiacoli and Klebsiellapneumoniae, we demonstrate the multiplexing capabilities of the device when it comes to both many samples in parallel and different resistance genes. As a final example, we combined the device with a novel protocol for rapid cultivation and extraction of plasmids from fecal samples collected from patients. This combined protocol will make it possible to analyze many patient samples in one device already on the day the sample is collected, which is an important step forward for the ODM analysis of plasmids in clinical diagnostics.
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Human brucellosis is neglected in southern Ethiopia. Although traditional food processing practices and animal husbandry which increase the risk of brucellosis are common, it has not been properly studied yet. This study was conducted to determine the seroepidemiology of brucellosis among apparently healthy individuals in southern Ethiopia. In the study, blood samples were collected to screen for serum agglutinins reactive to stained antigen of Brucella abortus Standard tube titration was performed for reactive serum to determine the titer of the agglutinin. A structured questionnaire was used to collect data on possible risk factors for brucellosis. The seroprevalence of human brucellosis in this study was found to be 10.6% (95% confidence interval = 7.0, 14.0). Possession of domestic ruminant animals, contact with ruminant animals, and husbandry practices at home were associated with seropositivity. The higher seroprevalence of human brucellosis in the study area needs attention and additional confirmatory investigation.
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Doadores de Sangue , Brucelose/epidemiologia , Doenças Negligenciadas/epidemiologia , Estudos Soroepidemiológicos , Zoonoses/epidemiologia , Adolescente , Adulto , Animais , Etiópia/epidemiologia , Feminino , Humanos , Masculino , Fatores de Risco , Adulto JovemRESUMO
BACKGROUND: Neisseria gonorrhoeae is a bacterium responsible for one of the classic sexually transmitted infection (STI) gonorrhea. Antibiotic resistant strains are emerging at alarming rate. Multiple sexual partners, unsafe sex and substance use habits are the main host related risk factors for acquiring the infection. Thus, this study aimed at determining the magnitude, its determinants and antimicrobial resistance profile of N. gonorrhoeae in a place where there is risk related cultural practices and relatively high HIV prevalence. METHODS: A cross-sectional study was conducted on 186 STI suspected patients seen in Gambella hospital from March to July 2015. Data on socio-demographic characteristics and associated risk factors was collected using pre-designed questionnaire. Urethral or endo-cervical swabs were collected aseptically by trained nurses. Then, samples were transported to laboratory and processed within 15 min following standard microbiological culture techniques. Antimicrobial susceptibility test was performed by using Kirby-Bauer disk diffusion method. Data entry, transforming and analysis was done using SPSS version 20. RESULTS: In this study 11.3 % of the STI suspected patients were confirmed to have N. gonorrhoeae. The rate of infection in males was four times higher than in females accounting 16.0 and 5.0 % respectively (p = 0.049). It was also higher (18.9 %) in 20-24 years age group (p = 0.439). Alcohol intake (p = 0.013), less frequent condom use (p = 0.031), and multiple sex partners (p = 0.024) were associated with increased odds of infection. All N. gonorrhoeae isolates were susceptible to ceftriaxone and cefoxitin but all were resistant to penicillin and tetracycline. Alarmingly, 28.6 % of the isolates were resistant to ciprofloxacin. CONCLUSIONS: The proportion of urogenital symptoms attributable to N. gonorrhoeae was high (11 %), with highest prevalence among males and young adults. Hence, prevention efforts should consider behavioral risk reduction. Ceftriaxone and cefoxitin can be considered as excellent first-line treatment options. However, alarming rate of resistance to ciprofloxacin challenges the current use of this antibiotic in the syndromic management package of gonococcal infections. Thus, laboratory based diagnosis and treatment system is need.
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Farmacorresistência Bacteriana , Hospitais , Neisseria gonorrhoeae/fisiologia , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/microbiologia , Adolescente , Adulto , Idoso , Anti-Infecciosos/farmacologia , Demografia , Farmacorresistência Bacteriana/efeitos dos fármacos , Etiópia/epidemiologia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Neisseria gonorrhoeae/efeitos dos fármacos , Fatores de Risco , Assunção de Riscos , Comportamento Sexual , Adulto JovemRESUMO
BACKGROUND: Pseudomonas aeruginosa is among the most common bacterial pathogens with wide spread distribution in health care settings. Despite advances in medical and surgical care and introduction of wide variety of antimicrobial agents, Pseudomonas aeruginosa continues to cause life threatening infection. Thus, this study aims to isolate and determine antimicrobial susceptibility patterns of Pseudomonas aeruginosa from catheterized patients with urinary tract infection. RESULT: A cross-sectional study was conducted from January to May, 2013. Urine specimens of 73 catheterized patients who developed urinary tract infection after catheterization were collected from sampling port of the catheter. The urine samples were inoculated on MaConckey and blood agar plates, and incubated at 37 °C for 24 h. The isolates were identified by conventional microbiological tests. Antimicrobial susceptibility pattern was determined by modified Kirby-Bauer disk diffusion method. From a total of 73 urine samples collected P. aeruginosa was isolated from 36 (49.32%) catheterized patients; 17 (23.29%) males and 19 (26.03%) females. While all P. aeruginosa isolates were found to be susceptible to Norfloxacin and Ciprofloxacin most isolates were also susceptible to Gentamicin (86.12%). CONCLUSION: The result shows higher prevalence of P. aeruginosa isolates among catheterized patients and the isolates were susceptible to the antimicrobials studied. All P. aeruginosa isolates were susceptible to Ciprofloxacin and Norfloxacin with some of the isolates shown resistance to Gentamicin. While the susceptibility of the isolates to the two fluoroquinolones is a good news for the prescribers their future rational prescription and use should be the main focus.
Assuntos
Anti-Infecciosos/farmacologia , Cateterismo , Hospitais de Ensino , Hospitais Universitários , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Adolescente , Adulto , Etiópia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Tuberculosis (TB) is a cause of 1.2-1.5 million deaths worldwide, including deaths from TB among HIV positive people. Determining the extent of immune cells belonging to cell mediated immunity and haematological parameters is critical to maximize the potential benefit of anti-tubercular treatment and case management. MATERIALS AND METHODS: Comparative cross sectional study was conducted to determine the white blood cell (WBC) count, CD4, CD8, haemoglobin (Hgb), red blood cell (RBC) count, mean corpuscular haemoglobin (MCHC), mean corpuscular volume (MCV) between newly diagnosed TB patients and apparently healthy controls (HCs). RESULTS: From consecutively enrolled 108 TB patients, pulmonary TB (PTB) accounted for 48(44.4%), TB lymphadenitis accounted for 48(44.4%), and disseminated/miliary TB accounted for 12(11.1%). Analysis of variance revealed that mean ± SD of CD4 count of male TB patients (650 ± 224cells/µl) was significantly lower than male control group (883 ± 256 cells/µl) (p= 0.001). In a similar manner, the mean CD4 count of female TB patients (793 ± 332cells/µl) was lower than female control group (975 ± 300 cells/µl) (p=0.001). There was no statistically significant difference in CD8 counts between cases and controls for both genders. Forty (37.0%) TB patients had developed anaemia of whom 22(55%) were among PTB, 13(32.5%) from tuberculous lymphadenitis and 5(20%) from disseminated TB. Morphologically, from all anaemia among TB patients, normocytic normochromic anaemia accounted for 15(37.5%) followed by normocytic hypochromic anaemia 13(30.4%). CONCLUSION: CD4 lymphopenia was significant among TB patients. Granulocyte count was increased. Mild anaemia was found major haematological abnormality among newly diagnosed TB patients.
Assuntos
Anemia/complicações , Linfócitos T CD4-Positivos/metabolismo , Linfadenite/etiologia , Linfopenia/etiologia , Tuberculose/complicações , Adolescente , Adulto , Análise de Variância , Anemia/sangue , Anemia/epidemiologia , Contagem de Linfócito CD4 , Estudos Transversais , Etiópia/epidemiologia , Feminino , Granulócitos/metabolismo , Hospitais Universitários , Humanos , Linfadenite/epidemiologia , Linfopenia/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Tuberculose/sangue , Tuberculose/imunologia , Tuberculose Miliar/sangue , Tuberculose Miliar/complicações , Tuberculose Miliar/epidemiologia , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/epidemiologia , Adulto JovemRESUMO
Introduction. Campylobacter is one of the leading bacterial causes of food-borne disease. The prevalence of Campylobacter species resistant to antimicrobial agents is increasing. This study is intended to determine prevalence and antimicrobial susceptibility patterns of Campylobacter species among under-five children with diarrhea. Methodology. A cross-sectional study was conducted among 227 under-five children with diarrhea from July to October 2012 at Jimma town. Isolation and identification of Campylobacter species were performed using standard bacteriological techniques. Antimicrobial susceptibility test was performed following standard protocol. Chi-square and Fisher's exact tests were used for analysis. Results. From 227 under-five children, 16.7% were positive for Campylobacter spp.; isolates, C. jejuni, C. coli, and C. lari, accounted for 71.1%, 21.1%, and 7.9%, respectively. Higher rate of resistance was observed to ampicillin 76.3%, trimethoprim-sulfamethoxazole (68.4%), tetracycline (39.5%), chloramphenicol (31.6%), clindamycin (26.3%), and doxycycline (23.7%). Erythromycin, ciprofloxacin, gentamicin, norfloxacin, and nalidixic acid were effective for more than 80% of the isolates. Multiple drug resistance was observed among 78.9% of all the three spp. Conclusions. Isolation rate of Campylobacter spp. was high. C. lari was reported for the first time at this study area. Higher rate of resistance was observed to the commonly used drugs.
RESUMO
BACKGROUND: Unsafe working practices, working environments, disposable waste products, and chemicals in clinical laboratories contribute to infectious and non-infectious hazards. Staffs, the community, and patients are less safe. Furthermore, such practices compromise the quality of laboratory services. We conducted a study to describe safety practices in public hospital laboratories of Oromia Regional State, Ethiopia. METHOD: Randomly selected ten public hospital laboratories in Oromia Regional State were studied from Oct 2011- Feb 2012. Self-administered structured questionnaire and observation checklists were used for data collection. The respondents were heads of the laboratories, senior technicians, and safety officers. The questionnaire addressed biosafety label, microbial hazards, chemical hazards, physical/mechanical hazards, personal protective equipment, first aid kits and waste disposal system. The data was analyzed using descriptive analysis with SPSS version16 statistical software. RESULT: All of the respondents reported none of the hospital laboratories were labeled with the appropriate safety label and safety symbols. These respondents also reported they may contain organisms grouped under risk group IV in the absence of microbiological safety cabinets. Overall, the respondents reported that there were poor safety regulations or standards in their laboratories. There were higher risks of microbial, chemical and physical/mechanical hazards. CONCLUSION: Laboratory safety in public hospitals of Oromia Regional State is below the standard. The laboratory workers are at high risk of combined physical, chemical and microbial hazards. Prompt recognition of the problem and immediate action is mandatory to ensure safe working environment in health laboratories.