Journal of medical microbiology最新文献

{"title":"Accuracy of classification of urinary Gram-stain findings by a computer-aided diagnosis app compared with microbiology specialists.","authors":"Kei Yamamoto, Goh Ohji, Isao Miyatsuka, Kei Furui-Ebisawa, Ataru Moriya, Shogo Maeta, Hidetoshi Nomoto, Masami Kurokawa, Kenichiro Ohnuma, Mari Kusuki, Yukari Uemura, Norio Ohmagari","doi":"10.1099/jmm.0.002008","DOIUrl":"https://doi.org/10.1099/jmm.0.002008","url":null,"abstract":"<p><p><b>Introduction.</b> Timely and accurate diagnosis of bacterial infections enables early administration of appropriate antimicrobial treatment and improved outcomes.<b>Hypothesis/Gap Statement.</b> The accuracy of computer-aided diagnosis (CAD) for identifying organisms on urine Gram stains has not been compared with that of microbiology specialists (MS).<b>Aim.</b> To compare the interpretation of urine Gram-stain results by MS and a CAD app designed using artificial intelligence.<b>Methodology.</b> Urine specimens from patients with urinary tract infections were used and collected at two tertiary hospitals between 1 April and 31 December 2022. Using non-inferiority analysis to assess whether CAD was non-inferior to expert interpretation, CAD-predicted microscopic findings of the Gram-stained slide generated from iPhone camera images from two hospitals were compared with those from ten MS. A total of 153 images were taken from each hospital, and CAD interpreted a total of 306. The primary endpoint was the prediction accuracy based on the morphology of the Gram-stained bacteria.<b>Results.</b> The accuracy (95% confidence interval) of MS and CAD predictions was 83.0% (81.6%-84.3%) and 87.9% (83.7%-91.3%), respectively, with a difference of -4.93% (-8.43% to -0.62%) indicating non-inferiority of CAD.<b>Conclusion.</b> CAD was non-inferior to MS predictions for identifying Gram-stained pathogens; therefore, CAD was suggested to have the potential for guiding empirical antibiotic selection in patients with urinary tract infections.</p>","PeriodicalId":94093,"journal":{"name":"Journal of medical microbiology","volume":"74 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12018707/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144055703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comments on 'Genotypic diversity of the <i>Helicobacter pylori vacA</i> c region and its correlation with gastric disease outcomes'.","authors":"Masoud Keikha","doi":"10.1099/jmm.0.002002","DOIUrl":"10.1099/jmm.0.002002","url":null,"abstract":"","PeriodicalId":94093,"journal":{"name":"Journal of medical microbiology","volume":"74 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11975057/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143797445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Causal relationship between gut microbiota and pyogenic arthritis: a two-sample Mendelian randomization study.","authors":"Ji-Ang Li, Chen-Han Zhou, Han-Dan Xiao, Hong-Bin Guo, Jie-Yu Liang, Yi Zhang","doi":"10.1099/jmm.0.002004","DOIUrl":"https://doi.org/10.1099/jmm.0.002004","url":null,"abstract":"<p><p><b>Introduction.</b> Accumulating evidence indicates a significant association between gut microbiota and the risk of developing pyogenic arthritis (PA). However, their causal relationship has yet to be elucidated.<b>Hypothesis.</b> The gut microbiota is causally associated with the risk of PA.<b>Aim.</b> The Mendelian randomization (MR) methodology was employed to assess the potential causal effects of gut microbiota on the susceptibility to PA.<b>Methodology.</b> A two-sample MR study was performed using the summary statistics of gut microbiota from the largest available genome-wide association study meta-analysis (<i>n</i>=13,266) conducted by the MiBioGen consortium. The summary statistics of PA were obtained from the R11 release data provided by the FinnGen consortium (2,441 cases and 2,87,796 controls). Inverse-variance weighted (IVW) model, weighted median estimator model, weighted model-based method and MR-Egger regression (MER) model were used to examine the causal association between gut microbiota and PA. To assess the heterogeneity and pleiotropic effects of the identified instrumental variables (IVs), we utilized several analytical methods, including the leave-one-out sensitivity analysis, the MR Pleiotropy Residual Sum and Outlier test and Cochran's Q test.<b>Results.</b> Utilizing the IVW method, we identified six bacterial traits that were negatively correlated with PA: <i>Eubacterium eligens</i> group [OR: 0.6057; 95 % confidence interval (CI): 0.4525 to 0.8107; <i>P</i>=0.0007], <i>Barnesiella</i> (OR: 0.7456; 95 % CI: 0.5760 to 0.9651; <i>P</i>=0.0258), <i>Coprococcus2</i> (OR: 0.7257; 95 % CI: 0.5352 to 0.9840; <i>P</i>=0.0391), <i>Ruminococcaceae</i> UCG005 (OR: 0.7562; 95 % CI: 0.5920 to 0.9660; <i>P</i>=0.0252), <i>E. oxidoreducens</i> group (OR: 0.7311; 95 % CI: 0.5547 to 0.9637; <i>P</i>=0.0262) and <i>Lachnospiraceae FCS020</i> group (OR: 0.7825; 95 % CI: 0.6135 to 0.9981; <i>P</i>=0.0482), respectively. On the contrary, four bacterial traits were positively correlated with PA: <i>Adlercreutzia</i> (OR 1.3210, 95 % CI 1.0181-1.7141, <i>P</i>=0.0362), <i>Holdemania</i> (OR 1.2239, 95 % CI 1.0013-1.4960, <i>P</i>=0.0485), <i>Anaerostipes</i> (OR 1.3614, 95 % CI 1.0189-1.8191, <i>P</i>=0.0369) and <i>Butyricimonas</i> (OR 1.2627, 95 % CI 1.0016-1.5921, <i>P</i>=0.0484), respectively. No significant heterogeneity among IVs or evidence of horizontal pleiotropy was detected.<b>Conclusion.</b> Our research demonstrates a potential causal link between various gut microbiota and the risk of PA. Further research is imperative to elucidate the mechanisms by which gut microbiota influence the pathogenesis of PA.</p>","PeriodicalId":94093,"journal":{"name":"Journal of medical microbiology","volume":"74 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144046701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antimicrobial and antiparasitic potential of lupeol: antifungal effect on the <i>Candida parapsilosis</i> species complex and nematicidal activity against <i>Caenorhabditis elegans</i>.","authors":"Marrie da Silva Dutra, Paulo Ricardo Monteiro Araújo, Maria Gleiciane da Rocha, Vinícius Carvalho Pereira, Alyne Soares Freitas, Raissa Geovanna Pereira Lopes, Pedro Filho Noronha Souza, Raquel Carvalho Montenegro, Waldemiro de Aquino Pereira-Neto, Géssica Dos Santos Araújo, Rossana de Aguiar Cordeiro, José Júlio Costa Sidrim, Glaucia Morgana de Melo Guedes, Débora de Souza Collares Maia Castelo-Branco, Marcos Fábio Gadelha Rocha","doi":"10.1099/jmm.0.001976","DOIUrl":"10.1099/jmm.0.001976","url":null,"abstract":"<p><p><b>Introduction.</b> There is growing concern about infections caused by non-<i>albicans Candida</i> species, including species of the <i>Candida parapsilosis</i> complex - which have seen a considerable increase in cases during the COVID-19 pandemic - in addition to concern about nematode resistance to currently used anthelmintics.<b>Gap Statement.</b> Lupeol is a triterpenoid phytosterol that has a wide range of biological activities, although its antifungal and antiparasitic potential is still poorly explored. Additionally, its effect on the biofilm of the <i>C. parapsilosis</i> species complex has not yet been studied.<b>Aim.</b> This study aimed to investigate the antifungal effect of lupeol against <i>C. parapsilosis</i> complex species, in planktonic cells and mature biofilms, as well as its nematicidal potential against <i>Caenorhabditis elegans</i>. In addition, molecular docking was performed to identify potential target molecules for lupeol's antifungal effect.<b>Methodology.</b> Twelve strains of <i>C. parapsilosis</i> species complex were used. Planktonic susceptibility was performed through the broth microdilution assay, while the antibiofilm effect was investigated by measuring the biomass and metabolic activity. The antifungal mechanism of action of lupeol was investigated by target fishing. The evaluation of the nematicidal effect was performed using the <i>C. elegans</i> infection model.<b>Results.</b> Lupeol demonstrated antifungal activity against planktonic cells with a MIC between 64 and 512 µg ml^-1. In mature biofilms, lupeol was able to reduce biomass starting from a concentration of 1024 µg ml^-1 and reduce metabolic activity from a concentration of 64 µg ml^-1. It was observed that there was interaction of lupeol with the enzyme 14α-demethylase. Furthermore, lupeol had a nematicidal effect from a concentration of 64 µg ml^-1.<b>Conclusion.</b> Lupeol exhibits an antifungal effect on the <i>C. parapsilosis</i> species complex, in the planktonic and mature biofilm forms, possibly by affecting the ergosterol synthesis. Lupeol further demonstrated a nematicidal potential.</p>","PeriodicalId":94093,"journal":{"name":"Journal of medical microbiology","volume":"74 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11936342/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143574930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phenotype and genotype of carbapenem-resistant hypervirulent <i>Klebsiella pneumoniae</i> in a teaching hospital in Shanghai, China.","authors":"Wei Ma, Yuxiang Wan, Xuejiao Li, Xiaochun Huang, Changzi Deng, Qin Qin","doi":"10.1099/jmm.0.001960","DOIUrl":"10.1099/jmm.0.001960","url":null,"abstract":"<p><p><b>Introduction.</b> Carbapenem-resistant hypervirulent <i>Klebsiella pneumoniae</i> (CR-hvKP) is an emerging pathogen associated with severe clinical outcomes, prompting an urgent investigation into its genomic characteristics and pathogenic potential.<b>Hypothesis/Gap Statement.</b> We hypothesize that CR-hvKP strains exhibit high-level resistance and high virulence, leading to their rapid spread in clinical settings and posing a serious threat to clinical treatment.<b>Aim.</b> The aim of the study was to investigate the phenotype and genotype of CR-hvKP strains, reveal their resistance- and virulence-related genomic characteristics and elucidate the biological characteristics of high-virulence and high-resistance strains to provide molecular epidemiological data for clinical use.<b>Methodology.</b> Carbapenem-resistant <i>K. pneumoniae</i> (CRKP) strains were obtained from clinical samples, from January 2013 to December 2018. PCR amplification was conducted to screen for carbapenem genes. To evaluate the virulence potential of the isolates, we conducted various tests, including a string test, Galleria mellonella larvae infection test, capsular polysaccharide synthesis genotyping and genetic sequencing analyses. We used PFGE, multilocus sequence typing and next-generation sequencing to detect the genetic relationship and homology of the strains.<b>Results.</b> In this study, we obtained 500 strains of CRKP, among which 18 strains were identified as CR-hvKP. All CR-hvKP strains were multidrug-resistant, exhibiting high-level resistance to most <i>β</i>-lactam antibiotics, including carbapenems. All CR-hvKP strains except N5 were positive for <i>bla</i>KPC-2, of which 14 isolates belonged to capsular serotype K64. Ten unrelated PFGE types were identified by PFGE analysis. Based on the results of PFGE, a total of 12 CR-hvKP isolates were selected from the 18 isolates for further testing, and 9 isolates had high homology with pLVPK virulence-related plasmids. All CR-hvKP strains showed high virulence in the Galleria mellonella infection model.<b>Conclusions.</b> The study revealed the resistance- and virulence-related genomic characteristics of CR-hvKP strains and confirmed the high virulence of these strains. These results are of great significance for understanding the epidemiological characteristics and clinical treatment of CR-hvKP and provide basic data for the formulation of corresponding prevention and control strategies.</p>","PeriodicalId":94093,"journal":{"name":"Journal of medical microbiology","volume":"74 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11897171/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143560423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genomic insights into extended-spectrum <i>β</i>-lactamase- and plasmid-borne AmpC-producing <i>Escherichia coli</i> transmission between humans and livestock in rural Cambodia.","authors":"Ebraheem D Elmarghani, John H-O Pettersson, Clara Atterby, Rachel A Hickman, Sokerya Seng, Sorn San, Kristina Osbjer, Ulf Magnusson, Evangelos Mourkas, Josef D Järhult","doi":"10.1099/jmm.0.001988","DOIUrl":"10.1099/jmm.0.001988","url":null,"abstract":"<p><p><b>Introduction.</b> The global spread of extended-spectrum cephalosporinase-producing <i>Escherichia coli</i> (producing extended-spectrum <i>β</i>-lactamase or plasmid-borne AmpC, hereafter ESC-Ec) is a major public health concern. Whilst extensively studied in high-income countries, the transmission pathways between humans and animals in low- and middle-income countries (LMICs) remain unclear. In rural Cambodia, the asymptomatic carriage and transmission dynamics of ESC-Ec between humans and animals living in close proximity are poorly understood, highlighting the need for targeted research in this area.<b>Gap statement.</b> An enhanced understanding of the genetic epidemiology of ESC-Ec can enable mitigation strategies to reduce the burden of disease and drug-resistant infections in LMIC settings.<b>Aim.</b> This study aimed to investigate the genetic relatedness and genotypic antibiotic resistance profiles of ESC-Ec strains from humans and livestock in rural Cambodia and to identify patterns of antimicrobial resistance (AMR) gene transmission between hosts and across households and villages.<b>Methodology.</b> Faecal samples were collected from 307 humans and 285 livestock in 100 households in or near Kampong Cham Province in rural Cambodia. From these samples, 108 ESC-Ec strains were subjected to whole-genome sequencing. Core genome MLST (cgMLST) and phylogenetic analysis determined genetic relationships between strains. All strains were screened for the presence of antibiotic resistance genes and plasmids.<b>Results.</b> Human and livestock isolates were assigned to six phylogroups, with phylogroup A being the most common (56.5%). MLST identified 50 sequence types (STs), 17 of which were shared between humans and animals, with ST155 being the most prevalent. cgMLST revealed 97 distinct cgMLST sequence types (cgST), indicating strain sharing between humans and animals. Additionally, AMR gene analysis showed widespread resistance, with genes from the <i>bla</i> _CTX-M group detected in 84.2% of isolates. Notably, AMR genes such as <i>aph(3'')-Ib-sul2</i> co-occurred in 50% of isolates. Finally, plasmid analysis identified IncF plasmids in 75.9% of isolates, likely facilitating AMR gene transmission across hosts.<b>Conclusions.</b> Our findings demonstrate that ESC-Ec strains and their AMR genes are transmitted between humans and livestock in rural Cambodia, likely driven by both clonal spread and plasmid-mediated horizontal gene transfer. These results highlight the urgent need for antimicrobial stewardship and infection control strategies to mitigate the spread of multidrug-resistant pathogens in both human and animal populations.</p>","PeriodicalId":94093,"journal":{"name":"Journal of medical microbiology","volume":"74 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11915462/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143627255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of whole-genome sequencing protocols for detection of antimicrobial resistance, virulence factors and mobile genetic elements in antimicrobial-resistant bacteria.","authors":"Gabriel Cipriani, Karin Helmersen, Ricardo Ruiz Mazzon, Glauber Wagner, Hege Vangstein Aamot, Fabienne Antunes Ferreira","doi":"10.1099/jmm.0.001990","DOIUrl":"10.1099/jmm.0.001990","url":null,"abstract":"<p><p><b>Introduction.</b> Antimicrobial resistance (AMR) poses a critical threat to global health, underscoring the need for rapid and accurate diagnostic tools. Methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) and extended-spectrum beta-lactamase (ESBL)-producing <i>Klebsiella pneumoniae</i> (ESBL-Kp) are listed among the World Health Organization's priority pathogens.<b>Hypothesis.</b> A rapid nanopore-based protocol can accurately and efficiently detect AMR genes, virulence factors (VFs) and mobile genetic elements (MGEs) in MRSA and ESBL-Kp, offering performance comparable to or superior to traditional sequencing methods.<b>Aim.</b> Evaluate whole-genome sequencing (WGS) protocols for detecting AMR genes, VFs and MGEs in MRSA and ESBL-Kp, to identify the most accurate and efficient tool for pathogen profiling.<b>Methodology.</b> Five distinct WGS protocols, including a rapid nanopore-based protocol (ONT20h) and four slower sequencing methods, were evaluated for their effectiveness in detecting genetic markers. The protocols' performances were compared across AMR genes, VFs and MGEs. Additionally, phenotypic antimicrobial susceptibility testing was performed to assess concordance with the genomic findings.<b>Results.</b> Compared to four slower sequencing protocols, the rapid nanopore-based protocol (ONT20h) demonstrated comparable or superior performance in AMR gene detection and equivalent VF identification. Although MGE detection varied among protocols, ONT20h showed a high level of agreement with phenotypic antimicrobial susceptibility testing.<b>Conclusion.</b> The findings highlight the potential of rapid WGS as a valuable tool for clinical microbiology, enabling timely implementation of infection control measures and informed therapeutic decisions. However, further studies are required to optimize the clinical application of this technology, considering costs, availability of bioinformatics tools and quality of reference databases.</p>","PeriodicalId":94093,"journal":{"name":"Journal of medical microbiology","volume":"74 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11923095/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143660220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"<i>Parachlamydia acanthamoebae</i>: disease-causing pathogen or opportunistic bystander?","authors":"Simone E Adams, Carole Kebbi-Beghdadi, Mirja Puolakkainen, Gilbert Greub, On Behalf Of The Escmid Study Group For Mycoplasma And Chlamydia Infections Esgmac","doi":"10.1099/jmm.0.001953","DOIUrl":"10.1099/jmm.0.001953","url":null,"abstract":"<p><p><b>Introduction.</b> <i>Parachlamydia acanthamoebae</i> is an obligate intracellular bacterium related to disease-causing bacteria like <i>Chlamydia trachomatis</i> and <i>Chlamydia pneumoniae</i> and is thus classified within the <i>Chlamydiales</i> order. <i>Parachlamydia</i> was initially discovered within an <i>Acanthamoeba</i> strain isolated from water in a humidifier during an investigation of an outbreak of respiratory infections in humans.<b>Gap Statement.</b> The disease-causing potential of this bacterium is not fully understood, but <i>Parachlamydia</i> has been associated with bronchiolitis, bronchitis, aspiration pneumonia and community-acquired pneumonia in humans. Additionally, diagnostic testing for <i>Parachlamydia</i> infection is not routinely performed, indicating that prevalence is underreported.<b>Aim.</b> This JMM profile aims to gauge what is currently known about the pathogenic potential of <i>P. acanthamoebae</i> and bring awareness to gaps in knowledge.<b>Results.</b> Amoebae appear to be the main reservoir of <i>P. acanthamoebae</i> and likely enter the nasal passages through contaminated water sources or contact with contaminated animals. The infected amoebae may then descend to the lower respiratory tract where the lytic cycle is triggered, causing human infection.<b>Conclusion.</b> By implementing serology and molecular testing, as well as conducting additional epidemiological studies, a better understanding of the association of human colonization with disease outcomes can be achieved.</p>","PeriodicalId":94093,"journal":{"name":"Journal of medical microbiology","volume":"74 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143660219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Epidemiology and management of infections in critically ill neonates: findings from a cohort study in a Brazilian neonatal intensive care unit.","authors":"Isadora Caixeta da Silveira Ferreira, Ralciane de Paula Menezes, Mallu Santos Mendonça Lopes, Lúcio Borges de Araújo, Daniela Marques de Lima Mota Ferreira, Denise Von Dolinger de Brito Röder","doi":"10.1099/jmm.0.001968","DOIUrl":"10.1099/jmm.0.001968","url":null,"abstract":"<p><p><b>Introduction.</b> Healthcare-associated infections (HAIs) are the leading cause of preventable death in neonatal intensive care units (NICUs), particularly among very low birth weight (VLBW) infants.<b>Hypothesis/Gap Statement</b>: VLBW neonates are at higher risk of HAIs, particularly those caused by Gram-negative bacteria (GNB) and fungi, which can negatively impact their survival and prolong hospitalization.<b>Aim.</b> To determine the risk factors, aetiology, antimicrobial susceptibility and clinical outcomes of HAIs in VLBW neonates in a Brazilian NICU.<b>Methodology.</b> This retrospective cohort study analysed the medical records of VLBW newborns admitted to the NICU from January 2015 to December 2022.<b>Results.</b> Among VLBW neonates, 269/670 (40.1%) developed HAIs and 203/670 (30.3%) developed sepsis. The incidence of HAIs (54.5% vs. 36.2%) and sepsis (49.7% vs. 25%) was higher in neonates weighing less than 750 g. The median birth weight of infected newborns was 960 g, and the median age of infection onset was 16 days. There were 292/456 (64%) infections caused by Gram-positive bacteria, 138/456 (30.3%) by GNB and 26/456 (5.7%) by fungi. Of the isolates, 277/456 (60.7%) were multidrug-resistant. Newborns weighing less than 750 g or infected with GNB and/or fungi had lower survival rates. Previous use of antifungals was the main predictor of infection (<i>P</i><0.01; odds ratio=4.21). Infections prolonged hospital stay from 25 to 42 days. The mortality rate was 17.6%, with a case lethality rate of 16.4%; 75% of deaths in the infected group were due to sepsis.<b>Conclusion.</b> The high incidence of infection emphasizes the need for infection control and antimicrobial management. Low birth weight is associated with increased risk of infection and decreased survival. The increase in GNB and fungal infections requires prevention and treatment strategies to reduce neonatal morbidity and mortality.</p>","PeriodicalId":94093,"journal":{"name":"Journal of medical microbiology","volume":"74 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11936347/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143702539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fractional inhibitory concentration of bio-actives from agricultural waste disassembles biofilms and quenches virulence of nosocomial pathogens.","authors":"Srividhya Krishnan, Ponnusami Venkatachalam, Saravanan Ramiah Shanmugam, Nithyanand Paramasivam","doi":"10.1099/jmm.0.001980","DOIUrl":"10.1099/jmm.0.001980","url":null,"abstract":"<p><p><b>Introduction.</b> The contact surfaces in hospitals serve as reservoirs for pathogens and account for 20-40% of hospital-acquired infections. This resistance is mainly attributed to the biofilm-forming ability of the microbes. These biofilms restrict the entry of the antibiotics to penetrate them, thus giving rise to drug resistance. Hence, there is a renewed interest in formulating an environmentally friendly, non-allergic, quick mode of action, broad-spectrum disinfectant.<b>Hypothesis.</b> We hypothesize that the pure compounds present in the pyrolysis aqueous phase could act as an anti-infective and anti-biofilm agent.<b>Aim.</b> The present work investigates the effectiveness of furfuryl alcohol, 2-methyl-2-cyclopentenone and guaiacol as effective anti-infective agent followed by testing its biofilm eradication potential against the mixed species of multidrug-resistant pathogens such as <i>Acinetobacter baumannii</i>, methicillin-resistant <i>Staphylococcus aureus</i> and <i>Candida auris</i>.<b>Methodology.</b> The MIC and fractional inhibitory concentrations (FIC) of the pure compounds were determined using checkerboard assay for two-compound and three-compound combinations. The biofilm eradication concentration was performed on stainless coupons, followed by RNA isolation and quantitative PCR (qPCR) analysis to elucidate virulence gene downregulation.<b>Results.</b> The individual MICs of furfuryl alcohol, 2-methyl-2-cyclopentenone and guaiacol were found to be 8%, 9% and 2% (v/v), respectively. The two-compound combination FIC index of 0.75 showed partial synergy between the compounds, while the three-compound combination showed an additive effect with a FIC index of 0.87. Further, at ½ FIC (biofilm inhibitory concentration), the compounds showed 52% eradication of preformed biofilms on the hospital contact surfaces (stainless steel). The growth and time-to-kill curve showed that the compounds were not lethal to planktonic cells at BIC. Finally, the qPCR analysis showed a reduction in the expression levels of biofilm and adhesion genes, while the Quorum sensing (QS) genes were affected much more, elucidating a possible eradication mechanism.<b>Conclusion.</b> From this study, we have found a new class of compounds that have potential disinfecting ability. With the current knowledge, the future lead would be to effectively use them in disinfectant formulations.</p>","PeriodicalId":94093,"journal":{"name":"Journal of medical microbiology","volume":"74 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11920071/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143660221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}