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Environmental Health Insights 2024The emergence and spread of antibiotic resistance (ABR) have been a public health challenge globally. The burden is even higher in low-income countries where there is a...
The emergence and spread of antibiotic resistance (ABR) have been a public health challenge globally. The burden is even higher in low-income countries where there is a lack of appropriate healthcare systems, and inappropriate antibiotic disposal practices and utilization. Due to poor solid waste disposal practices in developing nations, municipal solid waste dumpsite (MSWDS) can be a reservoir for ABR bacteria. However, only a few studies demonstrated the prevalence of ABR in non-clinical environments such as MSWDS. This study assessed the prevalence of ABR bacteria at Bahir Dar City MSWDS, to understand the public health risks related to poor solid waste disposal systems. Nine soil samples were collected from the dumpsite. Bacteria were isolated, identified and tested for ABR. Seventy-one distinct colonies were isolated from all samples and identified into 10 bacterial genera based on morphological features and biochemical tests. For ABR tests, gentamicin (GN, 10 μg), streptomycin (ST, 30 μg), tetracycline (TE, 30 μg), ciprofloxacin (CIP, 5 μg), nalidixic acid (NAA, 30 μg), sulfonamide (SA, 250 μg), chloramphenicol (C, 30 μg), erythromycin (E, 15 μg), vancomycin (V, 30 μg), and amoxicillin (AMX, 25 μg) were used. The most frequently isolated bacteria were (23%) followed by species (17%). Ten isolates related to spp. were excluded from the antibiotic sensitivity test as there is no standard regarding this genus in the Clinical and Laboratory Standards Institute. The overall antibiotic résistance rate was 95.08%, and most isolates were found to be resistant to amoxicillin (100%), nalidixic acid (75.5%), and vancomycin (75%). Substantial proportions of the isolates were also resistant to tetracycline (55.35%), streptomycin (54.5%), and sulfonamide (50%). The overall multidrug resistance (MDR) rate was 36.06%. This high level of ABR calls for urgent intervention in waste management systems and regular surveillance programs.
PubMed: 38859927
DOI: 10.1177/11786302241260508 -
Infection and Drug Resistance 2024Methicillin-resistant (MRSA) enteritis is a condition in which MRSA grows abnormally in the intestine after administration of antimicrobial agents, resulting in...
BACKGROUND
Methicillin-resistant (MRSA) enteritis is a condition in which MRSA grows abnormally in the intestine after administration of antimicrobial agents, resulting in enteritis. Patients with MRSA detected in stool culture tests are often diagnosed with MSRA enteritis. However, uncertainty remains in the diagnostic criteria; therefore, we conducted epidemiological studies to define these cases.
PATIENTS AND METHODS
Patients who tested positive for MRSA by stool culture using selective media 48 h after admission to Kochi Medical School Hospital between April 1, 2012, and December 31, 2022, and did not meet the exclusion criteria were included. We defined MRSA enteritis (Group A) as cases that were responsive to treatment with vancomycin hydrochloride powder, had a Bristol Stool Scale of ≥ 5, and a stool frequency of at least three times per day; all others were MRSA carriers (Group B). Multivariate analysis was performed to risk factors associated with MRSA enteritis.
RESULTS
Groups A and B included 18 (25.4%) and 53 (74.6%) patients, respectively. Multivariate logistic regression analysis showed that a white blood cell count of > 10000/µL (odds ratio [OR], 5.50; 95% confidence interval [CI], 1.12-26.9), MRSA count of ≥ 2+ in stool cultures (OR, 8.91; 95% CI, 1.79-44.3), and meropenem administration within 1 month of stool specimen submission (OR, 7.47; 95% CI, 1.66-33.6) were risk factors of MRSA enteritis.
CONCLUSION
The case definitions reviewed for MRSA enteritis may be useful as diagnostic criteria.
PubMed: 38854779
DOI: 10.2147/IDR.S459708 -
Water Research Aug 2024Since stormwater conveys a variety of contaminants into water bodies, green infrastructure (GI) is increasingly being adopted as an on-site treatment solution in...
Since stormwater conveys a variety of contaminants into water bodies, green infrastructure (GI) is increasingly being adopted as an on-site treatment solution in addition to controlling peak flows. The purpose of this study was to identify differences in microbial water quality of stormwater in watersheds retrofitted with GI vs. those without GI. Considering stormwater is recently recognized as a contributor to the antibiotic resistance (AR) threat, another goal of this study was to characterize changes in the microbiome and collection of AR genes (resistome) of urban stormwater with season, rainfall characteristics, and fecal contamination. MinION long-read sequencing was used to analyze stormwater microbiome and resistome from watersheds with and without GI in Columbus, Ohio, United States, over 18 months. We characterized fecal contamination in stormwater via culturing Escherichia coli and with molecular microbial source tracking (MST) to identify sources of fecal contamination. Overall, season and storm event (rainfall) characteristics had the strongest relationships with changes in the stormwater microbiome and resistome. We found no significant differences in microbial water quality or the microbiome of stormwater in watersheds with and without GI implemented. However, there were differences between the communities of microorganisms hosting antibiotic resistance genes (ARGs) in stormwater from watersheds with and without GI, indicating the potential sensitivity of AR bacteria to treatment. Stormwater was contaminated with high concentrations of human-associated fecal bacterial genes, and the ARG host bacterial community had considerable similarities to human feces/wastewater. We also identified 15 potential pathogens hosting ARGs in these stormwater resistome, including vancomycin-resistant Enterococcus faecium (VRE) and multidrug-resistant Pseudomonas aeruginosa. In summary, urban stormwater is highly contaminated and has a great potential to spread AR and microbial hazards to nearby environments. This study presents the most comprehensive analysis of stormwater microbiome and resistome to date, which is crucial to understanding the potential microbial risk from this matrix. This information can be used to guide future public health policy, stormwater reuse programs, and urban runoff treatment initiatives.
Topics: Microbiota; Water Microbiology; Rain; Ohio; Feces; Escherichia coli; Drug Resistance, Microbial; Water Quality
PubMed: 38852387
DOI: 10.1016/j.watres.2024.121873 -
The Journal of Infection Jun 2024
PubMed: 38848967
DOI: 10.1016/j.jinf.2024.106191 -
Euro Surveillance : Bulletin Europeen... Jun 2024BackgroundVancomycin-resistant enterococci (VRE) are increasing in Denmark and Europe. Linezolid and vancomycin-resistant enterococci (LVRE) are of concern, as treatment...
BackgroundVancomycin-resistant enterococci (VRE) are increasing in Denmark and Europe. Linezolid and vancomycin-resistant enterococci (LVRE) are of concern, as treatment options are limited. Vancomycin-variable enterococci (VVE) harbour the gene complex but are phenotypically vancomycin-susceptible.AimThe aim was to describe clonal shifts for VRE and VVE in Denmark between 2015 and 2022 and to investigate genotypic linezolid resistance among the VRE and VVE.MethodsFrom 2015 to 2022, 4,090 Danish clinical VRE and VVE isolates were whole genome sequenced. We extracted vancomycin resistance genes and sequence types (STs) from the sequencing data and performed core genome multilocus sequence typing (cgMLST) analysis for . All isolates were tested for the presence of mutations or genes encoding linezolid resistance.ResultsIn total 99% of the VRE and VVE isolates were From 2015 through 2019, 91.1% of the VRE and VVE were . During 2020, to the number of increased to 254 of 509 VRE and VVE isolates. Between 2015 and 2022, seven clusters dominated: ST80-CT14 , ST117-CT24 , ST203-CT859 ST1421-CT1134 (VVE cluster) ST80-CT1064 , ST117-CT36 and ST80-CT2406 We detected 35 linezolid vancomycin-resistant and eight linezolid-resistant VVEfm.ConclusionFrom 2015 to 2022, the numbers of VRE and VVE increased. The spread of the VVE cluster ST1421-CT1134 in Denmark is a concern, especially since VVE diagnostics are challenging. The finding of LVRE, although in small numbers, ia also a concern, as treatment options are limited.
Topics: Vancomycin-Resistant Enterococci; Enterococcus faecium; Humans; Denmark; Gram-Positive Bacterial Infections; Anti-Bacterial Agents; Bacterial Proteins; Carbon-Oxygen Ligases; Linezolid; Multilocus Sequence Typing; Microbial Sensitivity Tests; Vancomycin Resistance; Whole Genome Sequencing; Vancomycin; Genotype
PubMed: 38847117
DOI: 10.2807/1560-7917.ES.2024.29.23.2300633 -
Frontiers in Immunology 2024bacteremia (SAB) is a life-threatening infection particularly involving methicillin-resistant (MRSA). In contrast to resolving MRSA bacteremia (RB), persistent MRSA...
INTRODUCTION
bacteremia (SAB) is a life-threatening infection particularly involving methicillin-resistant (MRSA). In contrast to resolving MRSA bacteremia (RB), persistent MRSA bacteremia (PB) blood cultures remain positive despite appropriate antibiotic treatment. Host immune responses distinguishing PB vs. RB outcomes are poorly understood. Here, integrated transcriptomic, IL-10 cytokine levels, and genomic analyses sought to identify signatures differentiating PB vs. RB outcomes.
METHODS
Whole-blood transcriptomes of propensity-matched PB (n=28) versus RB (n=30) patients treated with vancomycin were compared in one independent training patient cohort. Gene expression (GE) modules were analyzed and prioritized relative to host IL-10 cytokine levels and DNA methyltransferase-3A () genotype.
RESULTS
Differential expression of T and B lymphocyte gene expression early in MRSA bacteremia discriminated RB from PB outcomes. Significant increases in effector T and B cell signaling pathways correlated with RB, lower IL-10 cytokine levels and heterozygous A/C genotype. Importantly, a second PB and RB patient cohort analyzed in a masked manner demonstrated high predictive accuracy of differential signatures.
DISCUSSION
Collectively, the present findings indicate that human PB involves dysregulated immunity characterized by impaired T and B cell responses associated with excessive IL-10 expression in context of the A/A genotype. These findings reveal distinct immunologic programs in PB vs. RB outcomes, enable future studies to define mechanisms by which host and/or pathogen drive differential signatures and may accelerate prediction of PB outcomes. Such prognostic assessment of host risk could significantly enhance early anti-infective interventions to avert PB and improve patient outcomes.
Topics: Humans; Bacteremia; Methicillin-Resistant Staphylococcus aureus; Staphylococcal Infections; Male; Female; Middle Aged; Gene Expression Profiling; Transcriptome; Aged; Interleukin-10; DNA Methyltransferase 3A; Anti-Bacterial Agents; Adult
PubMed: 38846955
DOI: 10.3389/fimmu.2024.1373553 -
Medecine Tropicale Et Sante... Mar 2024To determine the etiology of cervico-vaginal infections by cytobacteriology and the efficacy of qPCR for the diagnosis of sensitive strains such as and
OBJECTIVE
To determine the etiology of cervico-vaginal infections by cytobacteriology and the efficacy of qPCR for the diagnosis of sensitive strains such as and
METHODOLOGY
This prospective cross-sectional study was performed between January and September 2021 in 346 women who were examined for cervico-vaginal infection at the Hôpital Principal de Dakar (HPD). Cytobacteriological (direct examination, agar culture) and molecular analyses were performed.
RESULTS
Vaginal flora imbalances predominated, with a rate of 72.3%. The proportion of type IV vaginal flora was 46.5%. Of the 199 germs isolated, (25.1%), (17.6%), (7.8%), (6.6%) and nonalbicans (5.5%) were the main pathogens responsible for cervico-vaginal infections in patients. Among women tested for mycoplasma, was identified in 43.3% of patients. Among those tested for the proportion of infected women was low (4%). The prevalence of was higher in pregnant women (38.3%) than in nonpregnant women (19.2%). strains showed high resistance to certain beta-lactam antibiotics (pristinamycin 100%, gentamycin 100%, ampicillin 92.5% and cefalotin 85.2%) and to a glycopeptide antibiotic (vancomycin 100%). The strain had good sensitivity to antibiotics except gentamycin (100%) and kanamycin (100%). The enterobacteria tested were all sensitive to phenicols, carbapenems, cephalosporins and aminoglycosides. However, showed high resistance to tetracycline. The different methods showed low prevalences of and so comparisons Test RapidChlamydia/qPCR for and culture/qPCR for N. were not possible. For on the other hand, qPCR was more advantageous than culture. The χ test showed a significant difference (Yates χ = 33.77 and p = 1) for the diagnosis of qPCR had a sensitivity of 40.7%, a specificity of 94%, and positive and negative predictive values of 36.7% and 94.9% respectively, as well as a kappa = 0.33.
CONCLUSION
The methods applied enabled us to identify the pathogens that cause cervicovaginal infections. The results suggest that qPCR may be an alternative, at least for the diagnosis of However, culture remains indispensable for studying antibiotic sensitivity. In order to improve patient care, molecular techniques need to be integrated into the HPD testing toolbox. To broaden the repertoire of pathogens to be diagnosed by qPCR, targeted comparison studies will be needed to increase the probability of encountering infected individuals.
Topics: Humans; Female; Senegal; Cross-Sectional Studies; Adult; Prospective Studies; Young Adult; Real-Time Polymerase Chain Reaction; Middle Aged; Adolescent; Vaginitis
PubMed: 38846122
DOI: 10.48327/mtsi.v4i1.2024.298 -
The Brazilian Journal of Infectious... 2024C. difficile has been increasingly reported as a cause of gastrointestinal disease in children, ranging from mild self-limiting diarrhea to severe conditions such as...
Molecular epidemiology and antimicrobial resistance in Clostridioides difficile strains isolated from children and adolescents in a tertiary referral pediatric hospital in Fortaleza, Brazil.
BACKGROUND
C. difficile has been increasingly reported as a cause of gastrointestinal disease in children, ranging from mild self-limiting diarrhea to severe conditions such as pseudomembranous colitis and toxic megacolon. Only two pediatric research groups reported the presence of C. difficile infection in Brazilian children, but no previous research has examined C. difficile infection among children in northeastern Brazil. This prospective cross-sectional study investigated the molecular epidemiology and antimicrobial resistance of C. difficile strains isolated from children and adolescents with diarrhea referred to a tertiary pediatric hospital in Brazil while exploring the associated risk factors.
RESULTS
Toxin positivity or C. difficile isolation was found in 30.4 % (17/56) samples. C. difficile was isolated from 35 % (6/17) samples. Four toxigenic strains were identified (tpi+, tcdA+, tcdB+, cdtB-, without tcdC deletions) belonging to PCR ribotypes and PFGE-pulsotypes: 046 (new pulsotype 1174), 106 (NAP11), 002 (new pulsotype 1274), 012 (new pulsotype NML-1235). Two of the six isolates belonging to ribotypes 143 and 133 were non-toxigenic. All toxigenic strains were sensitive to metronidazole and vancomycin. Regarding the clinical manifestation, diarrhea lasted an average of 11 days, ranging from 3 to 50 days and was often associated with mucus and/or blood. All six patients from whom the C. difficile was isolated had a chronic disease diagnosis, with these comorbidities as the main risk factors.
CONCLUSION
Our study enhances our understanding of the present epidemiological landscape of C. difficile-associated diarrhea (CDI) among children in northeastern Brazil, reveling a substantial CDI frequency of 30.4 %, with toxigenic strains detected in 76.4 % of cases, highlighting a higher prevalence compared to earlier Brazilian studies. In the globalized world, an understanding of disease-generating strains, the associated risk factors, clinical manifestation, and antimicrobial sensitivity has fundamental epidemiological importance and draws attention to preventive measures, allowing for more decisive action.
Topics: Humans; Clostridioides difficile; Child; Adolescent; Female; Male; Brazil; Cross-Sectional Studies; Prospective Studies; Tertiary Care Centers; Child, Preschool; Anti-Bacterial Agents; Clostridium Infections; Microbial Sensitivity Tests; Risk Factors; Infant; Hospitals, Pediatric; Molecular Epidemiology; Diarrhea; Ribotyping; Drug Resistance, Bacterial
PubMed: 38843868
DOI: 10.1016/j.bjid.2024.103767 -
International Journal of Medical... Jun 2024Staphylococcus aureus is a notorious pathogen responsible for various severe diseases. Due to the emergence of drug-resistant strains, the prevention and treatment of S....
Staphylococcus aureus is a notorious pathogen responsible for various severe diseases. Due to the emergence of drug-resistant strains, the prevention and treatment of S. aureus infections have become increasingly challenging. Vancomycin is considered to be one of the last-resort drugs for treating most methicillin-resistant S. aureus (MRSA), so it is of great significance to further reveal the mechanism of vancomycin resistance. VraFG is one of the few important ABC (ATP-binding cassette) transporters in S. aureus that can form TCS (two-component systems)/ABC transporter modules. ABC transporters can couple the energy released from ATP hydrolysis to translocate solutes across the cell membrane. In this study, we obtained a strain with decreased vancomycin susceptibility after serial passaging and selection. Subsequently, whole-genome sequencing was performed on this laboratory-derived strain MWA2 and a novel single point mutation was discovered in vraF gene, leading to decreased sensitivity to vancomycin and daptomycin. Furthermore, the mutation reduces autolysis of S. aureus and downregulates the expression of lytM, isaA, and atlA. Additionally, we observed that the mutant has a less net negative surface charge than wild-type strain. We also noted an increase in the expression of the dlt operon and mprF gene, which are associated with cell surface charge and serve to hinder the binding of cationic peptides by promoting electrostatic repulsion. Moreover, this mutation has been shown to enhance hemolytic activity, expand subcutaneous abscesses, reflecting an increased virulence. This study confirms the impact of a point mutation of VraF on S. aureus antibiotic resistance and virulence, contributing to a broader understanding of ABC transporter function and providing new targets for treating S. aureus infections.
Topics: Virulence; Staphylococcal Infections; Anti-Bacterial Agents; Vancomycin; Animals; ATP-Binding Cassette Transporters; Bacterial Proteins; Staphylococcus aureus; Microbial Sensitivity Tests; Vancomycin Resistance; Whole Genome Sequencing; Daptomycin; Mice; Autolysis; Humans; Point Mutation; Mutation; Female
PubMed: 38838390
DOI: 10.1016/j.ijmm.2024.151624 -
Journal of Ophthalmic Inflammation and... Jun 2024To report a case of endogenous endophthalmitis caused by the dematiaceous fungus Cladophialophora devriesii.
PURPOSE
To report a case of endogenous endophthalmitis caused by the dematiaceous fungus Cladophialophora devriesii.
METHODS
Observational case report and literature review.
CASE PRESENTATION
A 73-year-old female with a history of chronic obstructive pulmonary disease presented with a red and painful left eye. Examination revealed anterior segment inflammation and vitritis, indicative of endophthalmitis. She underwent core vitrectomy and intravitreal injection of vancomycin and amphotericin B. The vitreous sample showed inflammatory cells and fungal hyphae, and systemic amphotericin B and itraconazole were commenced for fungal endophthalmitis. Targeted amplification of the sample for bacterial DNA (V2-V3 region of 16 S rDNA) was negative, but fungal DNA targets (ITS1 and ITS2) were present, and their sequences were consistent with Cladophialophora devriesii. Phenotypic characterisation and sequencing of ITS1 and ITS2, carried out on cultured fungus from the sample, also revealed Cladophialophora devriesii. She received repeated intravitreal injections of voriconazole, and based on the antifungal susceptibility results, her systemic medication was changed to posaconazole. After 12 months, the eye showed no signs of inflammation, and posaconazole therapy was discontinued. After 3 months without antifungal medication, the inflammation recurred, and she was restarted on antifungal therapy for an additional 20 months. Another recurrence occurred 3 months after discontinuation of treatment, and a repeat vitreous sample confirmed the presence of Cladophialophora devriesii. She was started on isavuconazole, but developed seclusio pupillae and painful secondary glaucoma. Due to the duration and severity of the infection, the eye was enucleated. Histopathology revealed persistent fungal elements at the ciliary processes and the posterior lens surface.
CONCLUSIONS
This second reported case of endogenous endophthalmitis caused by Cladophialophora devriesii illustrates the role of vitreous sampling and molecular methods in diagnosis and treatment of fungal endophthalmitis. Despite early diagnosis and prolonged local and systemic antifungal therapy, it was not possible to achieve long-term control of the fungal infection.
PubMed: 38836962
DOI: 10.1186/s12348-024-00408-y