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Antimicrobial Resistance In Clostridium Difficile Ribotype 017, Korakrit Imwattana, Daniel R. Knight, Brian Kullin, Deirdre A. Collins, Papanin Putsathit, Pattarachai Kiratisin, Thomas V. Riley

Research outputs 2014 to 2021

Introduction:

Antimicrobial resistance (AMR) played an important role in the initial outbreaks of Clostridium difficile infection (CDI) in the 1970s. C. difficile ribotype (RT) 017 has emerged as the major strain of C. difficile in Asia, where antimicrobial use is poorly regulated. This strain has also caused CDI outbreaks around the world for almost 30 years. Many of these outbreaks were associated with clindamycin and fluoroquinolone resistance. AMR and selective pressure is likely to be responsible for the success of this RT and may drive future outbreaks.

Areas covered:

This narrative journalarticle summarizes the prevalence and mechanisms of AMR in …

Clostridium Difficile In Asia: Opportunities For One Health Management, Deirdre A. Collins, Thomas V. Riley

Research outputs 2014 to 2021

Clostridium difficile is a ubiquitous spore-forming bacterium which causes toxin-mediated diarrhoea and colitis in people whose gut microflora has been depleted by antimicrobial use, so it is a predominantly healthcare-associated disease. However, there are many One Health implications to C. difficile, given high colonisation rates in food production animals, contamination of outdoor environments by use of contaminated animal manure, increasing incidence of community-associated C. difficile infection (CDI), and demonstration of clonal groups of C. difficile shared between human clinical cases and food animals. In Asia, the epidemiology of CDI is not well understood given poor testing practices in many countries. …

Evolutionary And Genomic Insights Into Clostridioides Difficile Sequence Type 11: A Diverse Zoonotic And Antimicrobial-Resistant Lineage Of Global One Health Importance, Daniel R. Knight, Brian Kullin, Grace O. Androga, Frederic Barbut, Catherine Eckert, Stuart Johnson, Patrizia Spigaglia, Kazuhiro Tateda, Pei-Jane Tsai, Thomas V. Riley

Research outputs 2014 to 2021

Clostridioides difficile (Clostridium difficile) sequence type 11 (ST11) is well established in production animal populations worldwide and contributes considerably to the global burden of C. difficile infection (CDI) in humans. Increasing evidence of shared ancestry and genetic overlap of PCR ribotype 078 (RT078), the most common ST11 sublineage, between human and animal populations suggests that CDI may be a zoonosis. We performed whole-genome sequencing (WGS) on a collection of 207 ST11 and closely related ST258 isolates of human and veterinary/environmental origin, comprising 16 RTs collected from Australia, Asia, Europe, and North America. Core genome single nucleotide variant (SNV) analysis identified …

Recurrence Of Clostridium Difficile Infection In The Western Australian Population, M. Alfayyadh, Deirdre A. Collins, S. Tempone, R. Mccann, P. K. Armstrong, Thomas V. Riley, A. Cook

Research outputs 2014 to 2021

Clostridium difficile, the most common cause of hospital-associated diarrhoea in developed countries, presents major public health challenges. The high clinical and economic burden from C. difficile infection (CDI) relates to the high frequency of recurrent infections caused by either the same or different strains of C. difficile. An interval of 8 weeks after index infection is commonly used to classify recurrent CDI episodes. We assessed strains of C. difficile in a sample of patients with recurrent CDI in Western Australia from October 2011 to July 2017. The performance of different intervals between initial and subsequent episodes of CDI was investigated. …

Clostridium Difficile Ribotype 017–Characterization, Evolution And Epidemiology Of The Dominant Strain In Asia, Korakrit Imwattana, Daniel R. Knight, Brian Kullin, Deirdre A. Collins, Papanin Putsathit, Pattarachai Kiratisin, Thomas V. Riley

Research outputs 2014 to 2021

Clostridium difficile ribotype (RT) 017 is an important toxigenic C. difficile RT which, due to a deletion in the repetitive region of the tcdA gene, only produces functional toxin B. Strains belonging to this RT were initially dismissed as nonpathogenic and circulated largely undetected for almost two decades until they rose to prominence following a series of outbreaks in the early 2000s. Despite lacking a functional toxin A, C. difficile RT 017 strains have been shown subsequently to be capable of causing disease as severe as that caused by strains producing both toxins A and B. While C. difficile RT …

Microbiological Evaluation Of The Ability Of The Deko-190 Washer/Disinfector To Remove Clostridium Difficile Spores From Bedpan Surfaces, Deirdre A. Collins, Kerry C. Carson, Thomas V. Riley

Research outputs 2014 to 2021

BACKGROUND: Clostridium difficile is a major nosocomial pathogen causing mild diarrhoea to life-threatening pseudomembranous colitis, and its spores frequently contaminate hospital environments and equipment. Washer/Disinfectors (WDs) are commonly used to clean and decontaminate soiled equipment in health care facilities. This study aimed to evaluate the effectiveness of the DEKO-190 WD in removing C. difficile spores from bedpans.

METHODS: Plastic carriers were inoculated with suspensions of C. difficile spores in autoclaved (sterile) human faeces. The carriers were then taped to a sterile plastic bedpan which was subjected to short, long or intensive wash cycles in the WD using one of two …

Status Of Vaccine Research And Development For Clostridium Difficile, T.V. Riley, D. Lyras, G. R. Douce

Research outputs 2014 to 2021

Clostridium difficile associated disease is fundamentally associated with dysbiosis of the gut microbiome as a consequence of antibiotic use. This is because this sporulating, obligate anaerobe germinates and proliferates rapidly in the dysbiotic gut, which is an indirect consequence of their use. During its growth, C. difficile produces two toxins, toxin A (TcdA) and toxin B (TcdB), which are responsible for the majority of clinical symptoms associated with the disease. Three parenterally delivered vaccines, based on detoxified or recombinant forms of these toxins, have undergone or are undergoing clinical trials. Each offers the opportunity to generate high titres of toxin …

Different Molecular Characteristics And Antimicrobial Resistance Profiles Of Clostridium Difficile In The Asia-Pacific Region, Yun Luo, Elaine Cheong, Qiao Bian, Deirdre A. Collins, Julian Ye, Jeong Hwan Shin, Wing Cheong Yam, Tohru Takata, Xiaojun Song, Xianjun Wang, Mini Kamboj, Thomas Gottlieb, Jianmin Jiang, Thomas V. Riley, Yi-Wei Tang, Dazhi Jin

Research outputs 2014 to 2021

Molecular epidemiology of Clostridium difficile infection (CDI) has been extensively studied in North America and Europe; however, limited data on CDI are available in the Asia-Pacific region. A multicentre retrospective study was conducted in this region. C. difficile isolates were subjected to multilocus sequence typing (ST) and antimicrobial susceptibility testing. Totally, 394 isolates were collected from Hangzhou, Hong Kong, China; Busan, South Korea; Fukuoka, Japan; Singapore; Perth, Sydney, Australia; New York, the United States. C. difficile isolates included 337 toxin A-positive/B-positive/binary toxin-negative (A+B+CDT-), 48 A-B+CDT-, and nine A+B+CDT+. Distribution of dominant STs varied geographically with ST17 in Fukuoka (18.6%), Busan …

Genomic Delineation Of Zoonotic Origins Of Clostridium Difficile, Daniel R. Knight, Thomas V. Riley

Research outputs 2014 to 2021

Clostridium difficile is toxin-producing antimicrobial resistant (AMR) enteropathogen historically associated with diarrhea and pseudomembranous colitis in hospitalized patients. In recent years, there have been dramatic increases in the incidence and severity of C. difficile infection (CDI), and associated morbidity and mortality, in both healthcare and community settings. C. difficile is an ancient and diverse species that displays a sympatric lifestyle, establishing itself in a range of ecological niches external to the healthcare system. These sources/reservoirs include food, water, soil, and over a dozen animal species, in particular, livestock such as pigs and cattle. In a manner analogous to human infection, …

Effect Of Natural Products On The Production And Activity Of Clostridium Difficile Toxins In Vitro, Niloufar Roshan, Thomas Riley, Daniel R Knight, Katherine A Hammer

Research outputs 2014 to 2021

Clostridium difficile infection is a toxin-mediated disease of the colon. C. difficile virulence is primarily attributed to the production of toxin A and toxin B; thus this study was aimed to investigate the effect of a range of natural products on the production and activity of C. difficile toxins in vitro. Twenty-two natural products were investigated against four C. difficile strains. The activity of products against toxins was determined using Vero and HT-29 cells cytotoxicity and neutral red uptake assays. The indirect effect of products on toxin-mediated cytotoxicity was determined using the same cell lines. The effect of seven products …

Prevalence Of Binary Toxin Positive Clostridium Difficile In Diarrhoeal Humans In The Absence Of Epidemic Ribotype 027, Alan M. Mcgovern, Grace O. Androga, Daniel R. Knight, Mark W. Watson, Briony Elliott, Niki F. Foster, Barbara J. Chang, Thomas V. Riley

Research outputs 2014 to 2021

Virulence of Clostridium difficile is primarily attributed to the large clostridial toxins A and B while the role of binary toxin (CDT) remains unclear. The prevalence of human strains of C. difficile possessing only CDT genes (A¯B¯CDT ⁺) is generally low (< 5 %), however, this genotype is commonly found in neonatal livestock both in Australia and elsewhere. Zoonotic transmission of C. difficile has been suggested previously. Most human diagnostic tests will not detect A¯B¯CDT ⁺ strains of C. difficile because they focus on detection of toxin A and/or B. We performed a prospective investigation into the prevalence and genetic characteristics of A¯B¯CDT ⁺ C. difficile in symptomatic humans. All glutamate dehydrogenase or …

High Prevalence Of Toxigenic Clostridium Difficile In Public Space Lawns In Western Australia, Peter Moono, Su Chen Lim, Thomas V. Riley

Research outputs 2014 to 2021

Clostridium difficile is a well-established hospital pathogen. Recently, it has been detected increasingly in patients without hospital contact. Given this rise in community associated infections with C. difficile, we hypothesized that the environment could play an important role in transmission of spores outside the hospital. Lawn samples (311) collected in public spaces in the metropolitan area of Perth, Western Australia, from February to June 2016 were cultured for C. difficile. C. difficile was isolated from the samples by direct and enrichment culture, and characterized by standard molecular methods using toxin gene PCR and ribotyping. The overall prevalence of …