Access microbiologyPub Date : 2024-07-08eCollection Date: 2024-01-01DOI: 10.1099/acmi.0.000683.v5
C N Nwofor, N E Onyenwe, C B Osuoha
{"title":"Pathogenicity and enzyme screening of some selected non-dermatophytic moulds.","authors":"C N Nwofor, N E Onyenwe, C B Osuoha","doi":"10.1099/acmi.0.000683.v5","DOIUrl":"10.1099/acmi.0.000683.v5","url":null,"abstract":"<p><p>Ten non-dermatophytic moulds isolated from both symptomatic and asymptomatic cattle skin, including <i>Penicillum citrinum, Aspergillus welwitschiae, Aspergillus aculeatus, Curvularia kusanol, Cladosporium teniussmum, Pestalotiopsis microspora, Fusarium oxysporum, Fusarium linchenicola, Absidia</i> sp. and <i>Aspergillus fumigatus,</i> were subjected to a pathogenicity test using albino mice. These isolates were also screened for five enzymes using a standard plate method. Results from pathogenicity tests showed that <i>Absidia</i> sp., <i>Cladosporium tenuissimum</i> and <i>Aspergillus welwitschiae</i> were able to elicit discoloration, lesion production and alopecia on the albino mice skin, respectively, providing evidence of clinical symptoms associated with cutaneous mycoses. The enzyme screening results revealed the highest zone of activity for keratinase (65 mm), amylase (86 mm), protease (60 mm), lipase (60 mm) and cellulase (86 mm) which were observed on <i>Pestalotiopsis microspora</i>, <i>Aspergillus welwitschiae</i>, <i>Cladosporium tenuissimum</i>, <i>Aspergillus welwitschiae</i> and <i>Aspergillus welwitschiae</i> respectively. Pathogenicity tests showed that some of these moulds may be virulent and this can be attributed to their possession of some virulence factors, including secretion of hydrolytic enzymes.</p>","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"6 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11316586/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141918504","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":"Invasive Streptococcus pyogenes infection: a case report.","authors":"Samia Bazhar, Yassine ElBenaissi, Elmostafa Benaissa, Yassine Ben Lahlou, Mariama Chadli","doi":"10.1099/acmi.0.000767.v3","DOIUrl":"10.1099/acmi.0.000767.v3","url":null,"abstract":"<p><p>The Group A Streptococcus (GAS), also known as <i>Streptococcus pyogenes</i> (<i>S. pyogenes</i>), is a human pathogen causing various infections, ranging from mild, such as tonsillitis and impetigo, to severe and invasive conditions like septicemia and necrotizing fasciitis. Despite a decline in incidence and severity during the twentieth century due to antibiotics, there has been a reported increase in severe cases since the 1980s in industrialized countries. <i>S. pyogenes</i> is a human pathogen with a natural reservoir in the pharynx and skin, exhibits asymptomatic carriage in various body sites. It is responsible for a spectrum of clinical manifestations, from asymptomatic carriage to severe invasive infections. Transmission occurs through respiratory droplets or direct contact with skin lesions. Bacteriologically, <i>S. pyogenes</i> is a Gram-positive β-hemolytic streptococcus. This summary highlights a case of invasive Group A Streptococcus infection in a 28-year-old diagnosed at the microbiology laboratory of the Mohammed V Military Training Hospital in Rabat, Morocco. A 28-year-old patient, without any specific medical history, presented with acute febrile oligoarthritis. Following a recent flu-like syndrome and febrile tonsillitis, the patient experienced asymmetric inflammatory oligoarthralgia affecting the left knee, left ankle, and right shoulder, accompanied by functional impairment of the left lower limb. Upon admission, clinical examination revealed swelling, positive patellar tap, and sternal involvement. Laboratory and imaging findings indicated an abscessed collection in the left knee and anterior mediastinitis. Emergency aspirations revealed Group A Streptococcus, specifically <i>Streptococcus pyogenes</i>, leading to a diagnosis of septic arthritis. Dual antibiotic therapy and knee joint drainage resulted in symptom resolution after 45 days. The rise in severe Group A Streptococcus infection underscores the need for early detection and treatment. Widely sharing the French High Council for Public Health's antibiotic prophylaxis recommendations is crucial for awareness. Collaborating between clinicians and microbiologists is essential for effective management.</p>","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"6 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11316590/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141918500","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}
Access microbiologyPub Date : 2024-07-05eCollection Date: 2024-01-01DOI: 10.1099/acmi.0.000804.v3
Alexander J Cunliffe, Peter Askew, Gillian Iredale, Abby Marchant, James Redfern
{"title":"Methods to assess antibacterial, antifungal and antiviral surfaces in relation to touch and droplet transfer: a review, gap-analysis and suggested approaches.","authors":"Alexander J Cunliffe, Peter Askew, Gillian Iredale, Abby Marchant, James Redfern","doi":"10.1099/acmi.0.000804.v3","DOIUrl":"10.1099/acmi.0.000804.v3","url":null,"abstract":"<p><p>To help assess whether a potentially antimicrobial material, surface, or coating provides antimicrobial efficacy, a number of standardised test methods have been developed internationally. Ideally, these methods should generate data that supports the materials efficacy when deployed in the intended end-use application. These methods can be categorised based on their methodological approach such as suspension tests, agar plate/zone diffusion tests, surface inoculation tests, surface growth tests or surface adhesion tests. To support those interested in antimicrobial coating efficacy, this review brings together an exhaustive list of methods (for porous and non-porous materials), exploring the methodological and environmental parameters used to quantify antibacterial, antifungal, or antiviral activity. This analysis demonstrates that antimicrobial efficacy methods that test either fungi or viruses are generally lacking, whilst methods that test bacteria, fungi and viruses are not designed to simulate end-use/lack realistic conditions. As such, a number of applications for antimicrobial activity across medical touch screens, medical textiles and gloves and transport seat textiles are explored as example applications, providing guidance on modifications to existing methods that may better simulate the intended end-use of antimicrobial materials.</p>","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"6 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11316596/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141918501","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}
Access microbiologyPub Date : 2024-07-05eCollection Date: 2024-01-01DOI: 10.1099/acmi.0.000756.v3
Jake David Turnbull, Jo Dicks, Rachael Adkin, Alexander Dickinson, Dorota Kaushal, Mojisola Semowo, Hannah McGregor, Sarah Alexander
{"title":"Notification of bacterial strains made available by the United Kingdom National Collection of Type Cultures in 2022.","authors":"Jake David Turnbull, Jo Dicks, Rachael Adkin, Alexander Dickinson, Dorota Kaushal, Mojisola Semowo, Hannah McGregor, Sarah Alexander","doi":"10.1099/acmi.0.000756.v3","DOIUrl":"10.1099/acmi.0.000756.v3","url":null,"abstract":"<p><p>Here, we report on the one hundred and twenty-five bacterial strains made available by the National Collection of Type Cultures in 2022 alongside a commentary on the strains, their provenance and significance.</p>","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"6 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11316570/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141918503","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}
Access microbiologyPub Date : 2024-07-04eCollection Date: 2024-01-01DOI: 10.1099/acmi.0.000695.v4
Frederick J Passman, Jordan Schmidt, Danika Nicoletti
{"title":"The relationship between microbial population ATP and quantitative PCR bioburdens in diesel fuel microcosms.","authors":"Frederick J Passman, Jordan Schmidt, Danika Nicoletti","doi":"10.1099/acmi.0.000695.v4","DOIUrl":"10.1099/acmi.0.000695.v4","url":null,"abstract":"<p><p>Historically, fuel microbiology studies have relied on culture data. Potentially relevant but unculturable bacteria were not detected. Although ATP can quantify total microbial bioburdens in fuels, it cannot differentiate among the taxa present. Quantitative PCR (qPCR) testing promises to fill this gap by quantifying targeted amplicon sequences thereby detecting both culturable and non-culturable taxa and quantifying specifically targeted taxa. In this study, fluid samples drawn from the fuel, interface and water phases of fuel over water microcosms were tested for cellular ATP concentration ([cATP]) and qPCR bioburdens. Additionally, surface swab samples from steel corrosion coupon surfaces exposed to each of these three phases were collected and tested for total ATP concentration ([tATP]) and qPCR bioburdens. Statistical relationships between ATP and qPCR bioburdens were examined. Correlation coefficients between the two variables were matrix dependent and ranged from negligible (|<i>r</i>|=0.2) to strong (|<i>r</i>|=0.7). When results were categorized into negligible, moderate and heavy bioburdens, parameter agreement was again matrix dependent. Percentage agreement between [ATP] and qPCR gene copies ranged from 11 % to 89 % - with qPCR-bioburden ratings typically being greater than ATP-bioburden ratings.</p>","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"6 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11316577/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141918505","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":"Reducing Blood Culture Contamination Rates: Introduction of a Combined Education and Skin Antisepsis Intervention","authors":"Niamh Mullane, Niall O'Mara, Darragh Coffey, Aine Connolly, Isabelle O'Callaghan, Deborah Kelly, Deirdre Broderick, Caitriona Hickey","doi":"10.1099/acmi.0.000806.v3","DOIUrl":"https://doi.org/10.1099/acmi.0.000806.v3","url":null,"abstract":"\u0000 Background. Blood culture contamination (BCC) is an important quality concern in clinical microbiology as it can lead to unnecessary antimicrobial therapy in patients and increased workload for laboratory scientists. The Clinical Laboratory and Standards Institute recommend BCC rates to be <3 % and recently updated guidelines have set a new goal of 1 %. The aim of this project was to design and implement interventions to reduce BCC rates at our institution.\u0000 \u0000 Methods. We introduced a combined education and skin antisepsis intervention in a large Model 4 academic teaching hospital in the South of Ireland. BD ChloraPrep skin antisepsis applicators (2 % chlorhexidine gluconate/70 % isopropyl alcohol), licensed for use for blood culture specimen collection, were introduced, replacing Clinell (2 % chlorhexidine gluconate/70 % isopropyl alcohol) wipes. In addition, a multimodal education programme was designed and delivered. This consisted of a video demonstrating the recommended blood culture specimen collection technique using the new applicators as well as simulation training for all interns. The video was uploaded to the intranet as an educational resource available to all staff.\u0000 \u0000 Results. The interventions were implemented in July 2022 and BCC rates pre- and post-intervention were calculated. The average BCC rate for the 12 months preceding the intervention (July 2021 to July 2022) was 2.56 % with highest rates in the Emergency Department. This compared to an average rate of 2.2 % in the 12 months post-intervention (July 2022 to July 2023). In comparing the two rates the reduction in BCC rates between the two periods was not statistically significant (P=0.30).\u0000 \u0000 Conclusion. Overall BCC rates reduced but the difference between the two periods did not reach statistical significance. The resource-intensive nature of providing regular and timely feedback of contamination rates and the larger impact of in-person education and training over virtual modalities may explain the modest reduction. Further investments in these areas, particularly in the Emergency Department, will be necessary to further reduce rates in line with new recommendations.","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"15 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141710553","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}
Ingrid Hoff, Eivind Rath, Slobodanka Pena-Karan, Elisabeth Sivy Nginamau, A. Holm, T. Thune, Tehmina Mustafa
{"title":"Atypical presentation of varicella-zoster virus reactivation in a lung transplant patient: a case report","authors":"Ingrid Hoff, Eivind Rath, Slobodanka Pena-Karan, Elisabeth Sivy Nginamau, A. Holm, T. Thune, Tehmina Mustafa","doi":"10.1099/acmi.0.000763.v3","DOIUrl":"https://doi.org/10.1099/acmi.0.000763.v3","url":null,"abstract":"\u0000 Background. Varicella-zoster virus (VZV) is a human neurotropic virus which commonly causes infection during childhood, presenting as chickenpox. Later in life it may reactivate as herpes zoster. We report a rare manifestation of reactivation of VZV infection presenting as cutaneous vasculitis and varicella pneumonia in a lung transplant recipient.\u0000 \u0000 Case presentation. A 65-year-old man was lung transplanted bilaterally for emphysema and had repeated posttransplant chest infections and colonization with Pseudomonas aeruginosa. Nine months post-transplant he presented with dyspnoea and a cutaneous vasculitis-like eruption with a predilection over face, thorax and distal extremities. Initially, VZV reactivation was not suspected due to absence of the typical vesicular eruptions. The diagnosis was confirmed by VZV PCR from the swabs of the ulcer after skin punch biopsy of a lesion and from bronchoalveolar lavage (BAL). The histology of skin biopsy demonstrated epithelial damage and vascular damage but no typical epithelial virus associated changes. The patient responded to antiviral therapy with total remission of rash and VZV DNA was finally not detectable from repeated BAL after 29 days of therapy. However, the pulmonary radiological features and dyspnoea persisted due to reasons possibly unrelated to the VZV infection.\u0000 \u0000 Conclusion. Had it not been for the patient to mention the resemblance of the vasculitic rash with his primary VZV infection, the diagnosis would easily have been overlooked. In this case, the biopsy did not show typical histopathologic findings of VZV-vasculitis. What led the diagnosis was a PCR from the wound swab taken after the punch biopsy. This case serves as a reminder for atypical presentation of common conditions in immunosuppressed patients and that extensive diagnostic sampling may be warranted in this group.","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141705805","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":"In silico analysis of Ffp1, an ancestral Porphyromonas spp. fimbrillin, shows differences with Fim and Mfa","authors":"L. Acuña-Amador, F. Barloy-Hubler","doi":"10.1099/acmi.0.000771.v3","DOIUrl":"https://doi.org/10.1099/acmi.0.000771.v3","url":null,"abstract":"\u0000 Background. Scant information is available regarding fimbrillins within the genus Porphyromonas, with the notable exception of those belonging to Porphyromonas gingivalis, which have been extensively researched for several years. Besides fim and mfa, a third P. gingivalis adhesin called filament-forming protein 1 (Ffp1) has recently been described and seems to be pivotal for outer membrane vesicle (OMV) production.\u0000 \u0000 Objective. We aimed to investigate the distribution and diversity of type V fimbrillin, particularly Ffp1, in the genus Porphyromonas.\u0000 \u0000 Methods. A bioinformatics phylogenomic analysis was conducted using all accessible Porphyromonas genomes to generate a domain search for fimbriae, using hidden Markov model profiles.\u0000 \u0000 Results. Ffp1 was identified as the sole fimbrillin present in all analysed genomes. After manual verification (i.e. biocuration) of both structural and functional annotations and 3D modelling, this protein was determined to be a type V fimbrillin, with a closer structural resemblance to a Bacteroides ovatus fimbrillin than to FimA or Mfa1 from P. gingivalis.\u0000 \u0000 Conclusion. It appears that Ffp1 is an ancestral fimbria, transmitted through vertical inheritance and present across all Porphyromonas species. Additional investigations are necessary to elucidate the biogenesis of Ffp1 fimbriae and their potential role in OMV production and niche adaptation.","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"99 S7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141695865","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}
D. Seymour, G. Forshaw, M. Porteous, D. Mawer, F. Wiggins, A. Mitchell, C. Hewitt, T. Beetar-King, K.A. Davies, D. Jackson, M.J. Hannah, M. Pitcher, U. Arnold, R. Strachan, M.J. Killip, P. Nixon
{"title":"Investigating the effectiveness of commercially available mouthwash on SARS-CoV-2 in vivo using viable virus titre as the primary outcome. A randomised controlled trial","authors":"D. Seymour, G. Forshaw, M. Porteous, D. Mawer, F. Wiggins, A. Mitchell, C. Hewitt, T. Beetar-King, K.A. Davies, D. Jackson, M.J. Hannah, M. Pitcher, U. Arnold, R. Strachan, M.J. Killip, P. Nixon","doi":"10.1099/acmi.0.000722.v3","DOIUrl":"https://doi.org/10.1099/acmi.0.000722.v3","url":null,"abstract":"This multi-arm, parallel group, single-blinded randomised controlled trial aimed to assess three commercially available mouthwashes effectiveness against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This manuscript has been written in accordance with the CONSORT statement.\u0000 \u0000 Methods. Eligible participants were SARS-CoV-2 positive with a positive test in the last 72 h. All participants had mild to moderate symptoms and could provide five saliva samples over a 60 min period. Participants delivered a baseline saliva sample and then used a mouthwash as per manufacturer’s instructions. They provided further saliva samples at minute 1, 10, 30 and 60. Participants were randomised to one of four groups; OraWize+, Total Care Listerine, Cool Mint Listerine and water (control). The lab-based research team were blind to the intervention. The research question was: can SARS-CoV-2 be rendered inactive in saliva by using a mouthwash and how long does this effect last? The primary outcome was the amount of viable infectious SARS-CoV-2 virus in the sample, compared to the baseline sample. The secondary outcome measure was the amount of genetic material from the SARS-CoV-2 virus in the sample, measured via PCR testing.\u0000 \u0000 Results. In total 100 participants were recruited (25 per group). Eight participants did not receive the allocated intervention and did not have saliva samples collected. There were no adverse events. In total 42 of the 92 participants had viable virus which could be cultured at baseline. Statistical analysis of the primary outcome was not advised due to the reduced level of viable virus at baseline and the positive skewness present in the distribution of log10(titre) data. Observational data of the primary outcome measure is presented.\u0000 Analysis of the secondary outcome PCR measure showed that there was strong evidence for a decrease in SARS-CoV-2 RNA levels compared to water for all mouthwashes after 1 min, OraWize+ −0.49 (−0.92, –0.05), p-value 0.029, Cool Mint Listerine −0.81 (−1.25, –0.38), p-value<0.001, Total Care Listerine −1.05 (−1.48, –0.62), p-value<0.001. For the remaining timepoints there was generally no evidence of virus level reduction compared to water although there is weak evidence for a decrease at ten minutes using Total Care Listerine −0.44 (−0.88, 0.01), p-value 0.053.\u0000 \u0000 Conclusion. The three mouthwashes included in this trial observationally demonstrated a reduction in virus titre level 1 min after use, with virus levels normalising up to 60 min compared to the control. Although an interesting observation, this result could not be statistically analysed. Using the secondary outcome PCR measure all three included mouthwashes reduced virus levels compared to water at 1 min and these results were statistically significant. Clinically this result does not support the use of the included mouthwashes to reduce SARS-CoV-2 levels in saliva.","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"353 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141691725","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}
Access microbiologyPub Date : 2024-06-28eCollection Date: 2024-01-01DOI: 10.1099/acmi.0.000744.v3
Andrew Mead, Stefano Azzariti, Ludovic Pelligand
{"title":"Hollow-fibre infection model: adaptations for the culture and assessment of fastidious organisms.","authors":"Andrew Mead, Stefano Azzariti, Ludovic Pelligand","doi":"10.1099/acmi.0.000744.v3","DOIUrl":"10.1099/acmi.0.000744.v3","url":null,"abstract":"<p><p>The hollow-fibre infection model (HFIM) is a valuable <i>in vitro</i> platform for emulating antimicrobial drug pharmacokinetic profiles. Despite its potential, standardized protocols for HFIM operation, especially concerning fastidious organisms, are lacking. This study addresses this gap by examining challenges in culturing <i>Pasteurella multocida</i> and <i>Actinobacillus pleuropneumoniae</i>, two fastidious organisms, in the HFIM. Our findings reveal effective strategies to prevent system clogging, involving multiple freeze-thaw cycles of horse blood, centrifugation and cell straining to enhance the clarity of the Mueller-Hinton fastidious medium defined by the European Committee on Antimicrobial Susceptibility Testing and Clinical and Laboratory Standards Institute. Additionally, we propose that the provision of a CO<sub>2</sub> atmosphere, along with the utilization of gas-permeable tubing and gas vent filters, significantly facilitates the growth of fastidious organisms. Remarkably, both <i>P. multocida</i> and <i>A. pleuropneumoniae</i> were sustained for a period of up to 10 days under these optimized conditions. This study provides crucial insights into the modifications necessary to successfully culture fastidious organisms in the HFIM, paving the way for more accurate and representative <i>in vitro</i> models for antimicrobial drug testing. These advancements hold promise for advancing research in the field of antimicrobial pharmacokinetics and efficacy against challenging pathogens.</p>","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"6 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11261730/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141753789","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}