Pub Date : 2025-03-24DOI: 10.1016/j.anaerobe.2025.102951
Paul A. Lawson, Ralph S. Tanner
A brief history of techniques in anaerobic microbiology are presented leading up to the incorporation of several improvements we have used over the years to improve our culture of anaerobic microorganisms of environmental, industrial and clinical importance. Two overriding aspects from our combined 90 years of experience here are: the better one's control of anaerobic conditions and gas phases, the better results are obtained; techniques can and should be targeted for individual microorganisms and accompanying experiments. Continued improvements in anaerobic microbiology are expected and encouraged for the future.
{"title":"Cultivation of anaerobic bacteria: Foundations and principles","authors":"Paul A. Lawson, Ralph S. Tanner","doi":"10.1016/j.anaerobe.2025.102951","DOIUrl":"10.1016/j.anaerobe.2025.102951","url":null,"abstract":"<div><div>A brief history of techniques in anaerobic microbiology are presented leading up to the incorporation of several improvements we have used over the years to improve our culture of anaerobic microorganisms of environmental, industrial and clinical importance. Two overriding aspects from our combined 90 years of experience here are: the better one's control of anaerobic conditions and gas phases, the better results are obtained; techniques can and should be targeted for individual microorganisms and accompanying experiments. Continued improvements in anaerobic microbiology are expected and encouraged for the future.</div></div>","PeriodicalId":8050,"journal":{"name":"Anaerobe","volume":"93 ","pages":"Article 102951"},"PeriodicalIF":2.5,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143724611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-24DOI: 10.1016/j.anaerobe.2025.102957
Mariela Alvarado-Rodríguez , Carlos Quesada-Gómez
This study analyzed antimicrobial resistance in 119 Clostridium species isolates collected at a Costa Rican trauma hospital (2018–2022). Isolates were identified using MALDI-TOF, and antimicrobial susceptibility was assessed by E-test. C. perfringens, C. tertium, and Paeniclostridium sordellii were most prevalent species. All isolates were susceptible to amoxicillin-clavulanic acid, linezolid, and metronidazole; however, resistance rates of 20 % to vancomycin and 25 % to clindamycin were observed. C. sphenoides showed the highest minimum inhibitory concentration values. Based on these findings, empirical treatment strategies at the hospital now prioritize amoxicillin-clavulanic acid, linezolid, and metronidazole, while reducing reliance on clindamycin due to observed resistance patterns.
{"title":"Antimicrobial resistance profiles of Clostridium species isolated from post-traumatic infections in a Costa Rican hospital","authors":"Mariela Alvarado-Rodríguez , Carlos Quesada-Gómez","doi":"10.1016/j.anaerobe.2025.102957","DOIUrl":"10.1016/j.anaerobe.2025.102957","url":null,"abstract":"<div><div>This study analyzed antimicrobial resistance in 119 <em>Clostridium</em> species isolates collected at a Costa Rican trauma hospital (2018–2022). Isolates were identified using MALDI-TOF, and antimicrobial susceptibility was assessed by E-test. <em>C. perfringens, C. tertium,</em> and <em>Paeniclostridium sordellii</em> were most prevalent species. All isolates were susceptible to amoxicillin-clavulanic acid, linezolid, and metronidazole; however, resistance rates of 20 % to vancomycin and 25 % to clindamycin were observed. <em>C. sphenoides</em> showed the highest minimum inhibitory concentration values. Based on these findings, empirical treatment strategies at the hospital now prioritize amoxicillin-clavulanic acid, linezolid, and metronidazole, while reducing reliance on clindamycin due to observed resistance patterns.</div></div>","PeriodicalId":8050,"journal":{"name":"Anaerobe","volume":"93 ","pages":"Article 102957"},"PeriodicalIF":2.5,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143727598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-22DOI: 10.1016/j.anaerobe.2025.102956
Elisabeth Nagy, Ellen Jo Baron
{"title":"Obituary of Mike Cox (1945–2024)","authors":"Elisabeth Nagy, Ellen Jo Baron","doi":"10.1016/j.anaerobe.2025.102956","DOIUrl":"10.1016/j.anaerobe.2025.102956","url":null,"abstract":"","PeriodicalId":8050,"journal":{"name":"Anaerobe","volume":"93 ","pages":"Article 102956"},"PeriodicalIF":2.5,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143680325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-19DOI: 10.1016/j.anaerobe.2025.102953
Jon J. Vernon , David W. Eyre , Mark H. Wilcox , Jane Freeman
Objectives
Reconstruct the phylogenetic status of a collection of historical Clostridioides difficile isolates and evaluate the congruence of their evolutionary trajectories with established molecular clock models.
Methods
Phylogenetic analysis was performed on Illumina sequence reads from previously analysed historic C. difficile isolates (1980–86; n = 75) demonstrating multiple antimicrobial resistances. Data was grouped by ribotype (RT), including comparators from European surveillance (2012–13) and phylogenetic studies (1985–2010). Reads were mapped to CD630/CD196 reference genomes and compared using recombination-adjusted maximum likelihood trees. Prediction intervals for expected SNP differences by age were calculated using a Poisson distribution and molecular clock estimates (0.74 SNPs per genome/per year). Root-to-tip analysis was performed to determine the date of most common recent ancestor of genomes sharing a ribotype.
Results
Moxifloxacin-resistant (>16 mg/L) RT027 isolate JV67 (1986) was two SNPs distinct from a 2006 genome, fewer than the expected lower estimate (4.4 SNPs) under current molecular clock calculations; (p = 3.93x10−5). For isolate JV02 (1981), the 13 SNP divergence from a 2008 isolate was consistent with expectations (5.9 SNPs; p = 0.07). JV73 (1983) demonstrated an 8 SNP difference, which although above the expected lower limit (5.5 SNPs), was outside the 95 % prediction interval; (p = 4.51x10−3). Only sixty-nine percent of historical genomes fit within the prediction interval for the number of SNPs expected compared to recent isolates, with fewer SNPs observed more frequently than expected. Root-to-tip analysis demonstrated a weak linear correlation.
Conclusions
C. difficile molecular clock estimations may be more complex than previously considered, with periods of spore quiescence potentially complicating analyses.
{"title":"Molecular clock complexities of Clostridioides difficile","authors":"Jon J. Vernon , David W. Eyre , Mark H. Wilcox , Jane Freeman","doi":"10.1016/j.anaerobe.2025.102953","DOIUrl":"10.1016/j.anaerobe.2025.102953","url":null,"abstract":"<div><h3>Objectives</h3><div>Reconstruct the phylogenetic status of a collection of historical <em>Clostridioides difficile</em> isolates and evaluate the congruence of their evolutionary trajectories with established molecular clock models.</div></div><div><h3>Methods</h3><div>Phylogenetic analysis was performed on Illumina sequence reads from previously analysed historic <em>C. difficile</em> isolates (1980–86; <em>n</em> = 75) demonstrating multiple antimicrobial resistances. Data was grouped by ribotype (RT), including comparators from European surveillance (2012–13) and phylogenetic studies (1985–2010). Reads were mapped to CD630/CD196 reference genomes and compared using recombination-adjusted maximum likelihood trees. Prediction intervals for expected SNP differences by age were calculated using a Poisson distribution and molecular clock estimates (0.74 SNPs per genome/per year). Root-to-tip analysis was performed to determine the date of most common recent ancestor of genomes sharing a ribotype.</div></div><div><h3>Results</h3><div>Moxifloxacin-resistant (>16 mg/L) RT027 isolate JV67 (1986) was two SNPs distinct from a 2006 genome, fewer than the expected lower estimate (4.4 SNPs) under current molecular clock calculations; (<em>p</em> = 3.93x10<sup>−5</sup>). For isolate JV02 (1981), the 13 SNP divergence from a 2008 isolate was consistent with expectations (5.9 SNPs; <em>p</em> = 0.07). JV73 (1983) demonstrated an 8 SNP difference, which although above the expected lower limit (5.5 SNPs), was outside the 95 % prediction interval; (<em>p</em> = 4.51x10<sup>−3</sup>). Only sixty-nine percent of historical genomes fit within the prediction interval for the number of SNPs expected compared to recent isolates, with fewer SNPs observed more frequently than expected. Root-to-tip analysis demonstrated a weak linear correlation.</div></div><div><h3>Conclusions</h3><div><em>C. difficile</em> molecular clock estimations may be more complex than previously considered, with periods of spore quiescence potentially complicating analyses.</div></div>","PeriodicalId":8050,"journal":{"name":"Anaerobe","volume":"93 ","pages":"Article 102953"},"PeriodicalIF":2.5,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143673198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Clostridium botulinum and botulinum neurotoxins have been recognized as an important food safety hazard. The objective of this study was to screen the prevalence of C. botulinum and botulinum toxin in various food products sold in the retail markets of India.
Material and methods
A total of 236 food products collected from Indian retail markets were screened for preformed botulinum toxin using a mouse bioassay. This was followed by enrichment and isolation and further testing of isolates for botulinum toxin production using an additional mouse bioassay. A toxin neutralization test with type specific antitoxins, 16S rRNA gene sequencing and BoNT (botulinum neurotoxin) gene amplification confirmed the presence of C. botulinum and its toxin production potential.
Results and discussion
Preformed botulinum toxin was not detected in any of the products. The overall prevalence of C. botulinum in the products was 11 %, but pure cultures of C. botulinum could be isolated only from 10 samples. The isolates were identified as C. botulinum type A, type B and type E based on toxin typing with type specific antitoxins and amplification of the botulinum neurotoxin (BoNT) gene. One of the isolates was designated as C. botulinum subtype A1B. This is the first report of isolation of C. botulinum type E and subtype A1B in seafood from India. The presence of C. botulinum in the products tested can be a significant public health hazard since the organism can grow when exposed to favourable conditions and can produce neurotoxin in the food.
{"title":"Prevalence of toxigenic Clostridium botulinum in food products sold in Indian retail markets","authors":"Athira Vidyadharan, Arun Jyothi Puthiya Veettil, Athira Pulickal Santhosh, Kuttanapilly Velayudhan Lalitha, Toms Cheriyath Joseph","doi":"10.1016/j.anaerobe.2025.102954","DOIUrl":"10.1016/j.anaerobe.2025.102954","url":null,"abstract":"<div><h3>Introduction</h3><div><em>Clostridium botulinum</em> and botulinum neurotoxins have been recognized as an important food safety hazard. The objective of this study was to screen the prevalence of <em>C. botulinum</em> and botulinum toxin in various food products sold in the retail markets of India.</div></div><div><h3>Material and methods</h3><div>A total of 236 food products collected from Indian retail markets were screened for preformed botulinum toxin using a mouse bioassay. This was followed by enrichment and isolation and further testing of isolates for botulinum toxin production using an additional mouse bioassay. A toxin neutralization test with type specific antitoxins, 16S rRNA gene sequencing and <em>BoNT</em> (botulinum neurotoxin) gene amplification confirmed the presence of <em>C. botulinum</em> and its toxin production potential.</div></div><div><h3>Results and discussion</h3><div>Preformed botulinum toxin was not detected in any of the products. The overall prevalence of <em>C. botulinum</em> in the products was 11 %, but pure cultures of <em>C. botulinum</em> could be isolated only from 10 samples. The isolates were identified as <em>C. botulinum</em> type A, type B and type E based on toxin typing with type specific antitoxins and amplification of the botulinum neurotoxin (<em>BoNT)</em> gene. One of the isolates was designated as <em>C. botulinum</em> subtype A<sub>1</sub>B. This is the first report of isolation of <em>C. botulinum</em> type E and subtype A<sub>1</sub>B in seafood from India. The presence of <em>C. botulinum</em> in the products tested can be a significant public health hazard since the organism can grow when exposed to favourable conditions and can produce neurotoxin in the food.</div></div>","PeriodicalId":8050,"journal":{"name":"Anaerobe","volume":"93 ","pages":"Article 102954"},"PeriodicalIF":2.5,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143673199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-15DOI: 10.1016/j.anaerobe.2025.102955
Isabela Leite de Oliveira Rosa, Eliane de Oliveira Ferreira, Ana Paula Vieira Colombo
Objectives
The oral cavity is the main gateway for the entry of C. difficile spores to the digestive tract. In conditions of poor oral hygiene and periodontal diseases, the dysbiotic oral microbiota may be a reservoir for several human pathogens. Here, we explored the prevalence of C. difficile in the oral microbiota of patients with severe periodontitis by the molecular detection of species specific genes.
Methods
Subgingival biofilm, saliva and/or feces from 659 patients with gingivitis, periodontitis and no periodontal diseases were screened for the tpi and toxin A/B genes specific for C. difficile by multiplex PCR. Differences among groups were sought by the Chi-square test.
Results
The overall frequency of C. difficile tpi gene was 29 %, with a high detection of tcdB gene (44.8 %). Patients with periodontitis showed a greater prevalence of this gene in the biofilm than individuals with gingivitis and periodontal health (p = 0.001), particularly at more severe stages of disease (p < 0.05). No toxin genes were detected in feces or biofilm from healthy patients, whereas >70 % of the biofilm from patients with periodontal diseases were positive for these genes (p < 0.001). Detection of C. difficile tpi gene in oral/fecal samples correlated with periodontal inflammation (p < 0.05). A modest intra-individual agreement between tpi gene detection in feces and saliva was found within periodontitis patients (Kappa = 0.314; p = 0.003).
Conclusion
The high frequency of the C. difficile specific genes tpi and tcdB in the dysbiotic subgingival biofilm of advanced periodontitis could support the presence of the bacterium in this niche.
{"title":"Molecular detection of toxigenic Clostridioides difficile in subgingival biofilm of severe periodontitis","authors":"Isabela Leite de Oliveira Rosa, Eliane de Oliveira Ferreira, Ana Paula Vieira Colombo","doi":"10.1016/j.anaerobe.2025.102955","DOIUrl":"10.1016/j.anaerobe.2025.102955","url":null,"abstract":"<div><h3>Objectives</h3><div>The oral cavity is the main gateway for the entry of <em>C. difficile</em> spores to the digestive tract. In conditions of poor oral hygiene and periodontal diseases, the dysbiotic oral microbiota may be a reservoir for several human pathogens. Here, we explored the prevalence of <em>C. difficile</em> in the oral microbiota of patients with severe periodontitis by the molecular detection of species specific genes.</div></div><div><h3>Methods</h3><div>Subgingival biofilm, saliva and/or feces from 659 patients with gingivitis, periodontitis and no periodontal diseases were screened for the <em>tpi</em> and toxin A/B genes specific for <em>C. difficile</em> by multiplex PCR. Differences among groups were sought by the Chi-square test.</div></div><div><h3>Results</h3><div>The overall frequency of <em>C. difficile tpi</em> gene was 29 %, with a high detection of <em>tcd</em>B gene (44.8 %). Patients with periodontitis showed a greater prevalence of this gene in the biofilm than individuals with gingivitis and periodontal health (p = 0.001), particularly at more severe stages of disease (p < 0.05). No toxin genes were detected in feces or biofilm from healthy patients, whereas >70 % of the biofilm from patients with periodontal diseases were positive for these genes (p < 0.001). Detection of <em>C. difficile tpi</em> gene in oral/fecal samples correlated with periodontal inflammation (p < 0.05). A modest intra-individual agreement between <em>tpi</em> gene detection in feces and saliva was found within periodontitis patients (Kappa = 0.314; p = 0.003).</div></div><div><h3>Conclusion</h3><div>The high frequency of the <em>C. difficile</em> specific genes <em>tpi</em> and <em>tcd</em>B in the dysbiotic subgingival biofilm of advanced periodontitis could support the presence of the bacterium in this niche.</div></div>","PeriodicalId":8050,"journal":{"name":"Anaerobe","volume":"93 ","pages":"Article 102955"},"PeriodicalIF":2.5,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143647230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-08DOI: 10.1016/j.anaerobe.2025.102952
William Johnston, Ryan Kean
Bacterial vaginosis (BV) is characterised by a polymicrobial biofilm forming on the vaginal epithelium. In this study, we have developed a host-pathogen model of BV to replicate disease. We demonstrated tissue colonisation by four key vaginal pathobionts that formed metronidazole tolerant biofilms, with subtle changes in cytotoxicity and inflammation.
{"title":"Development of a polymicrobial host-bacterial interface biofilm model for bacterial vaginosis","authors":"William Johnston, Ryan Kean","doi":"10.1016/j.anaerobe.2025.102952","DOIUrl":"10.1016/j.anaerobe.2025.102952","url":null,"abstract":"<div><div>Bacterial vaginosis (BV) is characterised by a polymicrobial biofilm forming on the vaginal epithelium. In this study, we have developed a host-pathogen model of BV to replicate disease. We demonstrated tissue colonisation by four key vaginal pathobionts that formed metronidazole tolerant biofilms, with subtle changes in cytotoxicity and inflammation.</div></div>","PeriodicalId":8050,"journal":{"name":"Anaerobe","volume":"93 ","pages":"Article 102952"},"PeriodicalIF":2.5,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143595977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bacteroides fragilis is one of the most frequently isolated pathogenic anaerobic bacteria. Infections caused by B. fragilis are commonly treated with carbapenems or tazobactam/piperacillin. However, there is no evidence for the optimal antibiotic choice against infections caused by B. fragilis as an empirical therapy owing to its varied antibiotic resistance mechanisms. Hence, we compared the effectiveness of carbapenems and tazobactam/piperacillin as an antibiotic therapy in patients infected with B. fragilis.
Methods
We investigated mortality, clinical and antimicrobial efficacy, and the percentage of patients who switched to broad-spectrum antibiotics, such as carbapenems or tazobactam/piperacillin, due to the aggravated symptoms of infection in patients receiving carbapenems or tazobactam/piperacillin from 2019 to 2024.
Results
A total of 60 patients were included in the study; 24 patients received carbapenems and 36 received tazobactam-piperacillin as an empirical treatment against B. fragilis infections. None of the patients in either group died. Compared to carbapenem treatment, tazobactam/piperacillin treatment significantly improved inflammatory markers, including body temperature and C-reactive protein (45.8 % vs. 72.2 %, p = 0.039 and 37.5 % vs. 63.4 %, p = 0.045, respectively; carbapenem vs. tazobactam/piperacillin). The percentage of patients switching from carbapenems to tazobactam/piperacillin or vice versa was significantly lower in the tazobactam/piperacillin group than in the carbapenem group (41.7 % vs. 11.1 %, p < 0.001).
Conclusions
Our findings suggest that tazobactam/piperacillin can be used as the first-line empirical treatment for patients infected with B. fragilis.
背景：脆弱拟杆菌是最常见的致病性厌氧菌之一。易裂芽孢杆菌引起的感染通常用碳青霉烯类或他唑巴坦/哌拉西林治疗。然而，由于脆弱芽孢杆菌的多种抗生素耐药机制，尚无证据表明针对脆弱芽孢杆菌感染的最佳抗生素选择是一种经验疗法。因此，我们比较了碳青霉烯类和他唑巴坦/哌拉西林作为抗生素治疗脆弱杆菌感染患者的有效性。方法：研究2019年至2024年期间，由于碳青霉烯类或他唑巴坦/哌拉西林感染症状加重，患者改用碳青霉烯类或他唑巴坦/哌拉西林等广谱抗生素的死亡率、临床和抗菌效果，以及患者比例。结果：共纳入60例患者；24例患者接受碳青霉烯类药物治疗，36例接受他唑巴坦-哌拉西林治疗。两组患者均未死亡。与碳青霉烯治疗相比，他唑巴坦/哌西林治疗显著改善炎症标志物，包括体温和c反应蛋白（分别为45.8%比72.2%,p = 0.039和37.5%比63.4%,p = 0.045）；碳青霉烯与他唑巴坦/哌拉西林)。他唑巴坦/哌拉西林组患者从碳青霉烯类药物转向他唑巴坦/哌拉西林或反之的比例显著低于碳青霉烯类药物组（41.7% vs. 11.1%, p < 0.001）。结论：他唑巴坦/哌拉西林可作为脆弱贝氏杆菌感染的一线经验治疗方案。
{"title":"A retrospective study comparing the effectiveness of carbapenems and tazobactam/piperacillin as an empirical treatment for patients infected with Bacteroides fragilis","authors":"Hideo Kato , Mao Hagihara , Nobuhiro Asai , Hiroshige Mikamo , Takuya Iwamoto","doi":"10.1016/j.anaerobe.2025.102950","DOIUrl":"10.1016/j.anaerobe.2025.102950","url":null,"abstract":"<div><h3>Background</h3><div><em>Bacteroides fragilis</em> is one of the most frequently isolated pathogenic anaerobic bacteria. Infections caused by <em>B. fragilis</em> are commonly treated with carbapenems or tazobactam/piperacillin. However, there is no evidence for the optimal antibiotic choice against infections caused by <em>B. fragilis</em> as an empirical therapy owing to its varied antibiotic resistance mechanisms. Hence, we compared the effectiveness of carbapenems and tazobactam/piperacillin as an antibiotic therapy in patients infected with <em>B. fragilis</em>.</div></div><div><h3>Methods</h3><div>We investigated mortality, clinical and antimicrobial efficacy, and the percentage of patients who switched to broad-spectrum antibiotics, such as carbapenems or tazobactam/piperacillin, due to the aggravated symptoms of infection in patients receiving carbapenems or tazobactam/piperacillin from 2019 to 2024.</div></div><div><h3>Results</h3><div>A total of 60 patients were included in the study; 24 patients received carbapenems and 36 received tazobactam-piperacillin as an empirical treatment against <em>B. fragilis</em> infections. None of the patients in either group died. Compared to carbapenem treatment, tazobactam/piperacillin treatment significantly improved inflammatory markers, including body temperature and C-reactive protein (45.8 % vs. 72.2 %, <em>p</em> = 0.039 and 37.5 % vs. 63.4 %, <em>p</em> = 0.045, respectively; carbapenem vs. tazobactam/piperacillin). The percentage of patients switching from carbapenems to tazobactam/piperacillin or vice versa was significantly lower in the tazobactam/piperacillin group than in the carbapenem group (41.7 % vs. 11.1 %, <em>p</em> < 0.001).</div></div><div><h3>Conclusions</h3><div>Our findings suggest that tazobactam/piperacillin can be used as the first-line empirical treatment for patients infected with <em>B. fragilis</em>.</div></div>","PeriodicalId":8050,"journal":{"name":"Anaerobe","volume":"92 ","pages":"Article 102950"},"PeriodicalIF":2.5,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143539745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Clostridioides difficile, a leading cause of healthcare-associated infections, causes significant morbidity and mortality. Its pathogenesis centers on TcdA and TcdB toxins, which disrupt intestinal integrity, trigger inflammation, and promote extensive neutrophil infiltration.
Objective
The main objective of this study was to evaluate the role of PMNs in CDI using neutrophil depletion in a murine-ileal-ligated loop.
Methods
Mice were treated with C. difficile toxins TcdA, TcdB, and TcdBv, with PMN depletion achieved via intraperitoneal injections of Ly6G/Ly6C antibody. Histopathological analysis, cytokine quantification, and MPO activity assays were performed to assess the inflammatory and tissue damage responses.
Results
PMN depletion significantly reduced histopathological damage and proinflammatory responses. TcdA induced the highest inflammation and epithelial damage, while TcdB showed lower activity, except for MPO. TcdBvNAP1's activity was comparable to that of TcdBNAP1 but less than TcdA. The findings indicate that TcdA's enterotoxin effects are more damaging than TcdBs from different strains and confirm the critical role of PMNs in CDI pathogenesis.
Conclusion
Our results show that PMN depletion reduced inflammatory responses and tissue damage, highlighting potential therapeutic strategies targeting PMN regulation. Further research on PMN extracellular traps (NETs) and their role in CDI is necessary to develop comprehensive treatments. Future studies should focus on combined in vivo and in vitro approaches to fully understand the pathological mechanisms and identify effective biomarkers for CDI therapy.
{"title":"Polymorphonuclear neutrophil depletion in ileal tissues reduces the immunopathology induced by Clostridioides difficile toxins","authors":"Montoya-Torres Brayan , Alfaro-Alarcón Alejandro , Quesada-Gómez Carlos , Chaves-Olarte Esteban , Barquero-Calvo Elías","doi":"10.1016/j.anaerobe.2025.102947","DOIUrl":"10.1016/j.anaerobe.2025.102947","url":null,"abstract":"<div><h3>Introduction</h3><div><em>Clostridioides difficile</em>, a leading cause of healthcare-associated infections, causes significant morbidity and mortality. Its pathogenesis centers on TcdA and TcdB toxins, which disrupt intestinal integrity, trigger inflammation, and promote extensive neutrophil infiltration.</div></div><div><h3>Objective</h3><div>The main objective of this study was to evaluate the role of PMNs in CDI using neutrophil depletion in a murine-ileal-ligated loop.</div></div><div><h3>Methods</h3><div>Mice were treated with <em>C. difficile</em> toxins TcdA, TcdB, and TcdBv, with PMN depletion achieved via intraperitoneal injections of Ly6G/Ly6C antibody. Histopathological analysis, cytokine quantification, and MPO activity assays were performed to assess the inflammatory and tissue damage responses.</div></div><div><h3>Results</h3><div>PMN depletion significantly reduced histopathological damage and proinflammatory responses. TcdA induced the highest inflammation and epithelial damage, while TcdB showed lower activity, except for MPO. TcdBv<sub>NAP1</sub>'s activity was comparable to that of TcdB<sub>NAP1</sub> but less than TcdA. The findings indicate that TcdA's enterotoxin effects are more damaging than TcdBs from different strains and confirm the critical role of PMNs in CDI pathogenesis.</div></div><div><h3>Conclusion</h3><div>Our results show that PMN depletion reduced inflammatory responses and tissue damage, highlighting potential therapeutic strategies targeting PMN regulation. Further research on PMN extracellular traps (NETs) and their role in CDI is necessary to develop comprehensive treatments. Future studies should focus on combined <em>in vivo</em> and <em>in vitro</em> approaches to fully understand the pathological mechanisms and identify effective biomarkers for CDI therapy.</div></div>","PeriodicalId":8050,"journal":{"name":"Anaerobe","volume":"92 ","pages":"Article 102947"},"PeriodicalIF":2.5,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143536405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-26DOI: 10.1016/j.anaerobe.2025.102945
A. Neubeck , N. Callac , S. Isaksson , A. Schnürer
This study investigated the long-term potential of low-temperature serpentinization of dunite to support the growth of the hydrogenotrophic methanogen Methanoculleus bourgensis strain MAB1. Incubation experiments were conducted for over 800 days, using dunite powder as the sole energy source, with and without the addition of nickel, an essential cofactor for methanogenesis. The results indicated that hydrogen released from dunite was sufficient to sustain methanogen growth, but the process was slow, with methane production beginning only after approximately 300 days. The release of toxic metals from dunite, particularly zinc, appeared to inhibit methanogen growth over time, leading to the cessation of methane production after 528 days and likely the lysing of the methanogenic cells. The study suggests that hydrogen availability, rather than nickel, is the limiting factor for methanogen growth in these conditions.
{"title":"Growth of hydrogenotrophic methanogen Methanoculleus bourgensis MAB1 in the presence of dunite","authors":"A. Neubeck , N. Callac , S. Isaksson , A. Schnürer","doi":"10.1016/j.anaerobe.2025.102945","DOIUrl":"10.1016/j.anaerobe.2025.102945","url":null,"abstract":"<div><div>This study investigated the long-term potential of low-temperature serpentinization of dunite to support the growth of the hydrogenotrophic methanogen <em>Methanoculleus bourgensis</em> strain MAB1. Incubation experiments were conducted for over 800 days, using dunite powder as the sole energy source, with and without the addition of nickel, an essential cofactor for methanogenesis. The results indicated that hydrogen released from dunite was sufficient to sustain methanogen growth, but the process was slow, with methane production beginning only after approximately 300 days. The release of toxic metals from dunite, particularly zinc, appeared to inhibit methanogen growth over time, leading to the cessation of methane production after 528 days and likely the lysing of the methanogenic cells. The study suggests that hydrogen availability, rather than nickel, is the limiting factor for methanogen growth in these conditions.</div></div>","PeriodicalId":8050,"journal":{"name":"Anaerobe","volume":"92 ","pages":"Article 102945"},"PeriodicalIF":2.5,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143531190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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