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J S Brazier

Publications and source records attributed to J S Brazier.

At least 19 recordsLinked to original sources
PubMed2006

Comparative phylogenomics of Clostridium difficile reveals clade specificity and microevolution of hypervirulent strains.

Clostridium difficile is the most frequent cause of nosocomial diarrhea worldwide, and recent reports suggested the emergence of a hypervirulent strain in North America and Europe. In this study, we applied comparative phylogenomics (whole-genome comparisons using DNA microarrays combined with Bayesian phylogenies) to model the phylogeny of C. difficile, including 75 diverse isolates comprising hypervirulent, toxin-variable, and animal strains. The analysis identified four distinct statistically supported clusters comprising a hypervirulent clade, a toxin A(-) B(+) clade, and two clades with human and animal isolates. Genetic differences among clades revealed several genetic islands relating to virulence and niche adaptation, including antibiotic resistance, motility, adhesion, and enteric metabolism. Only 19.7% of genes were shared by all strains, confirming that this enteric species readily undergoes genetic exchange. This study has provided insight into the possible origins of C. difficile and its evolution that may have implications in disease control strategies.

Animals↗
PubMed2005

A modified pulsed-field gel electrophoresis (PFGE) protocol for subtyping previously non-PFGE typeable isolates of Clostridium difficile polymerase chain reaction ribotype 001.

A modified pulsed-field gel electrophoresis (PFGE) protocol was developed and applied to 50 isolates of the UK epidemic strain of Clostridium difficile, polymerase chain reaction (PCR) ribotype 001, to develop a PFGE-based subtyping scheme. This protocol overcame the inherent DNA degradation problems associated with typing this strain of C. difficile by this method, and whole genomic digestion with SmaI restriction enzyme yielded seven distinct and reproducible PFGE banding patterns. Modified PFGE is an appropriate method for subtyping C. difficile PCR ribotype 001 that could be used to improve epidemiological investigations.

Bacterial Typing Techniques↗
PubMed2005

Anaerobic sepsis due to multidrug-resistant Bacteroides fragilis: microbiological cure and clinical response with linezolid therapy.

We describe the first reported case of anaerobic sepsis due to Bacteroides fragilis with simultaneous resistance to metronidazole, beta-lactams, beta lactam/beta-lactamase inhibitors, carbapenems, macrolides, and tetracyclines. Microbiological cure and clinical improvement was achieved with linezolid therapy, an agent that may be useful for the treatment of multidrug-resistant anaerobic infections.

Acetamides↗
PubMed2005

Subtyping of Clostridium difficile polymerase chain reaction (PCR) ribotype 001 by repetitive extragenic palindromic PCR genomic fingerprinting.

Fifty isolates of the most common UK strain of Clostridium difficile [polymerase chain reaction (PCR) ribotype 001] were analysed by three PCR-based typing methods in order to determine genomic diversity within this strain that may form the basis of a subtyping method. The three methods used were repetitive extragenic palindromic elements (REP), conserved repetitive DNA elements (BOX), and enterobacterial repetitive PCR intergenic consensus sequences (ERIC). The performance of each typing method was assessed by comparing powers of discrimination, typeability and reproducibility. All methods had satisfactory levels of typeability and reproducibility as determined by blind-coded repeats, but REP-PCR typing proved to be the most discriminatory method, yielding seven distinct amplicon profiles consisting of up to eight major bands. BOX-PCR generated between two and five major amplicons with four distinct BOX profiles. ERIC-PCR primers, however, could not discriminate between isolates. These results suggest that PCR ribotype 001 is not clonal in nature at present, and that REP-PCR subtyping methods offer promise to further our understanding of the epidemiology of C. difficile PCR ribotype 001 disease in UK hospitals.

Belgium↗
PubMed2005

Antimicrobial susceptibility of polymerase chain reaction ribotypes of Clostridium difficile commonly isolated from symptomatic hospital patients in the UK.

Two hundred and seventy-one clinical isolates of Clostridium difficile, including the six most common polymerase chain reaction (PCR) ribotypes isolated from symptomatic patients in UK hospitals, were tested against nine antibiotics (imipenem, erythromycin, levofloxacin, piperacillin/tazobactam, ciprofloxacin, co-amoxiclav, cefotaxime, amoxicillin and clindamycin). All 271 strains were susceptible to co-amoxiclav, piperacillin/tazobactam and amoxicillin, and resistant to cefotaxime and ciprofloxacin. Variable degrees of resistance were found to imipenem, erythromycin, levofloxacin and clindamycin. Significantly greater resistance to erythromycin, levofloxacin and imipenem was found in virtually all members of the two most common PCR ribotypes, 001 and 106. Resistance to these agents may have played a part in their selection as the most common strains of C. difficile found in UK hospitals.

Anti-Bacterial Agents↗
PubMed2005

Soft tissue infections caused by spore-forming bacteria in injecting drug users in the United Kingdom.

From 2000 to May 2004 there has been a marked increase in illness resulting from spore-forming bacteria in injecting heroin users in the United Kingdom. Clostridium novyi caused 63 cases of severe illness in 2000 and seven further cases from 2001. Wound botulism first occurred in 2000 (six cases) with 51 further cases to March 2004. Tetanus occurred in 20 cases between late 2003 and March 2004. Infections with C. histolyticum (nine cases), C. sordellii (one case) and Bacillus cereus (one case) were also reported. The reasons for the increase in illness are unclear. The major risk factor was skin- or muscle-popping. The problem appears to be here to stay. This review describes the causative organisms, pathogenesis, clinical presentation, epidemiology and treatment of cases. Clinical vigilance and a high standard of anaerobic microbiology are essential. Clinicians and laboratories must report such cases (or likely cases) rapidly so that clusters can be rapidly identified, in order to control disease. Prevention relies on tetanus immunization.

Age Distribution↗
PubMed2004

Metronidazole resistance in Bacteroides spp. carrying nim genes and the selection of slow-growing metronidazole-resistant mutants.

OBJECTIVES: Human clinical isolates of Bacteroides spp. originating from patients in the UK were investigated for the presence of metronidazole resistance determinants (nim genes) and their presence was related to the MIC of metronidazole for the isolates. METHODS: Isolates were screened for susceptibility to a metronidazole disc and had their MIC determined by the Etest method. They were investigated for the presence of nim genes by PCR. An experiment to determine the effect of prolonged exposure to metronidazole was applied to nim-positive isolates with MICs below the therapeutic breakpoint. RESULTS: Fifty of 206 isolates (24%) were found to possess nim genes and these had MICs of metronidazole ranging from 1.5 to >256 mg/L with 24 (11.6%) above the therapeutic breakpoint of 16 mg/L. The remaining 26 nim-gene-positive isolates had MICs that were still below the therapeutic breakpoint, ranging from 1.5 to 6.0 mg/L. nim genes were not found in 156 (76%) isolates, and all but seven of these were susceptible to a 5 microg disc of metronidazole. Ten members of the group for which the MICs were below the therapeutic level were found to have slow-growing sub-populations with metronidazole MICs ranging from 8.0 to >256 mg/L that became evident after prolonged exposure to metronidazole in vitro. This resistance selection process was sometimes reversible after passage in the absence of metronidazole; however, seven of the 10 slow-growing mutants converted to stable high-level resistance (MIC >256 mg/L). CONCLUSIONS: Although the presence of nim genes per se does not always equate to therapeutic resistance, and other metronidazole resistance mechanisms may exist, this study has shown that prolonged exposure of nim-gene-carrying Bacteroides spp. to metronidazole can select for therapeutic resistance.

Amino Acid Sequence↗
PubMed2004

Real-time PCR investigation into the importance of Fusobacterium necrophorum as a cause of acute pharyngitis in general practice.

Fusobacterium necrophorum is recognized as the cause of a severe life-threatening illness characterized by bacteraemia with metastatic abscesses following an acute sore throat (Lemierre's disease). However, the importance of F. necrophorum as a cause of simple sore throat in the community is unknown. Using quantitative real-time PCR with primers targeting the rpoB gene, 100 routine throat swabs collected from patients presenting to general practitioners with pharyngitis were analysed for the presence of F. necrophorum-specific DNA. The results were compared with those obtained from throat swabs collected from 100 healthy subjects. Ten clinical samples were positive for F. necrophorum DNA, identified as F. necrophorum subspecies funduliforme, using a haemagglutinin-related protein gene-specific PCR assay. All the healthy controls were negative (two-tailed P value = 0.0015; Fisher exact test). These findings suggest that F. necrophorum may play a more important role as a cause of simple sore throat in the community than has been previously appreciated.

Acute Disease↗
PubMed2004

Outbreak of Clostridium histolyticum infections in injecting drug users in England and Scotland.

Clostridial infections in injecting drug users in the United Kingdom are a relatively new phenomenon that came to light in 2000 when cases of serious illness and deaths due to Clostridium novyi were recorded. In the period December 2003 to April 2004, the Anaerobe Reference Laboratory received twelve referrals of an extremely rare isolate, Clostridium histolyticum, from cases of infection in injecting drug users submitted from nine different hospitals in England and Scotland. Molecular typing of these isolates by two different methods of pulsed-field gel electrophoresis and PCR ribotyping revealed they are all indistinguishable, indicating a common source of the infections, most probably a batch of heroin that was recently distributed across the UK.

Adult↗
PubMed2003

Antibiotic susceptibilities of Gram-positive anaerobic cocci: results of a sentinel study in England and Wales.

OBJECTIVE: A sentinel study was carried out to determine the antimicrobial susceptibilities of Gram-positive anaerobic cocci (GPAC) freshly isolated from clinical material in diagnostic laboratories in England and Wales. METHODS: A total of 113 GPAC isolates consisting predominantly of current or former members of the genus Peptostreptococcus was obtained from 17 sentinel laboratories in England and one in Wales. Minimum inhibitory concentrations (MICs) of 10 antimicrobial agents were determined by the Etest method. The agents tested were: penicillin, tetracycline, erythromycin, cefoxitin, clindamycin, chloramphenicol, imipenem, co-amoxiclav, piperacillin/tazobactam and metronidazole. MIC50 and MIC90 values for each drug-species combination were calculated whenever suitable numbers of each species were obtained. RESULTS: Excellent spectra of activity (0% resistance) against GPAC were seen for metronidazole, piperacillin/tazobactam, cefoxitin, imipenem and chloramphenicol. Low degrees of resistance to co-amoxiclav (3.5%), clindamycin (7.1%), penicillin (7.1%) and significant degrees of resistance to tetracycline (41.6%) and erythromycin (27.4%) were detected. Some examples of putative macrolide-lincosamide linked resistance were noted in seven (6.2%) isolates of GPAC. CONCLUSION: This study is one of the largest susceptibility studies specifically on GPAC carried out to date and the resulting data may be of value to those involved in the empirical treatment of infections involving Gram-positive anaerobic cocci.

Anti-Bacterial Agents↗
PubMed2003

Heat and acid tolerance of Clostridium novyi Type A spores and their survival prior to preparation of heroin for injection.

Clostridium novyi Type A was implicated as a cause of an outbreak of serious illness and deaths among drug users in the United Kingdom who injected heroin intramuscularly. A contaminated batch of heroin was believed to be the source of infection. To test the ability of the outbreak strain to survive certain processes associated with heroin use, it was tested for its ability to survive a range of temperature and pH and the process used in preparation of "street" heroin for injection. C. novyi spores survived temperatures of up to 100 degrees C in aqueous solution for 5 min and survived pH 2.0 at ambient temperatures for a similar time. However, a combination of low pH and raised temperatures reduced survival times. An experiment reconstructing the "street" preparation of heroin demonstrated that any C. novyi spores present would survive this process and thus be capable of initiating infection under the right conditions.

Journal Article↗
PubMed2003

A European survey of diagnostic methods and testing protocols for Clostridium difficile.

OBJECTIVE: To conduct a survey of the methods used in clinical microbiology laboratories in Europe to diagnose infection with Clostridium difficile. METHODS: A questionnaire was devised and sent to a co-ordinating member of the Study Group in each of eight European countries. This co-ordinator was in charge of forwarding the questionnaire to hospital laboratories arbitrarily selected. The number of laboratories in each country was determined on the basis of one laboratory for 10,000 beds of hospitalization. This questionnaire covered different aspects pertaining to Clostridium difficile associated to diarrhea (CDAD) diagnosis such as circumstances of request, criteria used for undertaking C. difficile investigations, methods used for the diagnosis, etc. RESULTS: A total of 212 questionnaires were completed and submitted for analysis: 87.7% of laboratories reported routinely performing C. difficile diagnostic tests. Methods used included toxin detection (93%), culture (55%), and glutamate dehydrogenase (GDH) detection (5.9%). Among the laboratories detecting toxins, different enzyme immunoassays (EIA) and cytotoxicity assays were used in 79% and 17.3% of cases, respectively. Among the different strategies reported, 4.8% were considered suboptimal for the diagnosis of C. difficile infections, but marked discrepancies could be observed between countries. The overall incidence (median) of CDAD was estimated at 1.1 for 1,000 patient admissions. CONCLUSION: The results of this study suggest marked discrepancies between laboratories and also between countries regarding the criteria by which C. difficile is investigated for, and the methods and the strategies that are used for the diagnosis of C. difficile. These discrepancies could be explained by the lack of clear guidelines for C. difficile diagnosis in each country, and by the importance that physicians attach to C. difficile. Precise guidelines for C. difficile diagnosis would be the first step to make possible accurate comparison of the incidence and the epidemiology of CDAD from one hospital to another or from one country to another.

Bacterial Proteins↗
PubMed2003

Prevalent PCR ribotypes of clinical and environmental strains of Clostridium difficile isolated from intensive-therapy unit patients in Kuwait.

Ninety-five isolates of Clostridium difficile from symptomatic and asymptomatic patients and 18 from their environment in the intensive-therapy units (ITUs) of four teaching hospitals in Kuwait were typed by PCR amplification of rRNA intergenic spacer regions (PCR ribotyping). A total of 32 different ribotypes was detected among the clinical isolates. The predominant ribotypes from the clinical isolates were types 097 and 078, which accounted for approximately 40 % of all isolates in the ITUs in Kuwait. Ribotypes 097 (toxigenic), 078 (toxigenic) and 039 (non-toxigenic) were three distinct clones that were circulating in all four hospitals. Ribotypes 097, 078 and 076 (i.e. 50 % of isolates from symptomatic patients) were the predominant isolates associated with C. difficile-associated disease (CDAD). The environmental isolates belonged to a diverse range of ribotypes, with no particular types common to all the hospitals. Ribotype 078 was found only in the patient environment in Mubarak hospital, while ribotype 097 was restricted to Amiri hospital. The hospital environment occupied by symptomatic as well as symptom-free patients was contaminated with C. difficile. Eight new strains that did not match any in the PCR ribotype library established at the PHLS Anaerobe Reference Unit, Cardiff, UK, were assigned ribotypes 105, 125, 128, 129, 131, 134, 140 and 141. These findings show that the isolates associated with CDAD in Kuwait are different from those found in the UK and some other European countries.

Clostridioides difficile↗
PubMed2002

Isolation and identification of Clostridium spp. from infections associated with the injection of drugs: experiences of a microbiological investigation team.

Pathogenic species of the genus Clostridium may contaminate the materials used in the injection of drugs and under the right conditions may cause serious or life-threatening disease. C. novyi type A was implicated in an outbreak of severe infection with high mortality in injecting drug users who injected heroin extravascularly. The isolation of such highly oxygen-sensitive clostridia from clinical material may require adherence to enhanced methods and, once isolated, commercially available anaerobe identification kits alone may not give an accurate identification. Additional phenotypic tests that are useful in recognising the main pathogenic species are described. Differentiation of C. novyi type A from C. botulinum type C in reference laboratories was based on 16S rDNA sequence data and specific neutralisation of cytopathic effects in tissue culture.

Bacterial Typing Techniques↗
PubMed2002

Amplified fragment length polymorphism (AFLP) analysis of Clostridium novyi, C. perfringens and Bacillus cereus isolated from injecting drug users during 2000.

As part of the follow-up investigations associated with an outbreak of severe illness and death among illegal injecting drug users during 2000, 43 cultures of Clostridium novyi type A, 40 C. perfringens type A and 6 isolates of Bacillus cereus were characterised by amplified fragment length polymorphism (AFLP) analysis. Among the 43 C. novyi isolates, 23 different AFLP profiles were detected. The same AFLP profile was detected in isolates from 18 drug users investigated during 2000 from Scotland, England, the Republic of Ireland and Norway and a wound from a patient in 2000 who was not identified as a drug user. Unique AFLP profiles were obtained from four drug users from England and the Republic of Ireland, 10 historical isolates from culture collections, an isolate from food (1989) and three isolates from wounds (1995, 1991, 1988). The 40 C. perfringens isolates were from 13 drug users, the contents of one syringe and two samples of heroin. Sixteen AFLP types of C. perfringens were distinguished and there was little evidence for commonality among the isolates. The AFLP types of C. perfringens from heroin differed and were unique. Six isolates of B. cereus were from four drug users and two samples of heroin. Four different AFLP patterns were distinguished. Three AFLP types were isolated from four drug users. B. cereus isolates from an aspirate and a heroin sample collected from the same drug user were identical, and were also indistinguishable from an isolate from a groin infection in a second drug user. The AFLP type of the isolate from a second and unrelated heroin sample was unique. The AFLP results showed no or very limited evidence for commonality between the different isolates of B. cereus and C. perfringens. In marked contrast, the C. novyi isolates from the majority of the drug users during 2000 were homogeneous, suggesting a common source or clonal selection of a C. novyi type, or both, which either had an adaptive advantage in spore germination, survival or growth following the drug preparation and the injection procedure, or produced a more severe clinical presentation.

Animals↗
PubMed2002

Fusobacterium necrophorum infections in England and Wales 1990-2000.

In response to a marked increase in both the number of Fusobacterium necrophorum bacteraemia reports to the PHLS Communicable Disease Surveillance Centre and the number of F. necrophorum isolates referred to the PHLS Anaerobe Reference Unit in 1999, the data from both sources on F. necrophorum infections were reviewed for the decade 1990-2000. There were 208 reports of F. necrophorum bacteraemia (average 19/year; range 14-34/year) with a peak in incidence in the late winter months; 68% were from male patients and the peak age range was 16-23 years. Of 205 referred isolates of F. necrophorum, 122 (59%) were from blood cultures and these represented 58% of the bacteraemia reports; the others were from brain and soft tissue abscesses, pleural and joint fluids, eyes, ears and lymphatic tissue. The average number of referrals was 19/year (range 9-37/year). The peak year for bacteraemia reports (34) and isolate referrals (37) was 1999; this increase was not sustained in 2000. All isolates were susceptible to metronidazole, but 2% were resistant to penicillin and 15% to erythromycin. F. necrophorum continues to be a regular but uncommon cause of bacteraemia and metastatic abscesses following an acute sore throat, especially in young, otherwise healthy adults.

Abscess↗
PubMed2001

Typing of Clostridium difficile.

Clostridium difficile is primarily recognised as a nosocomially acquired pathogen manifesting in gastrointestinal disease subsequent to the patient receiving broad-spectrum antibiotics. Infection can be sporadic, but outbreaks commonly occur within a ward or hospital as a result of cross-infection. Since the 1980s, the epidemiology of C. difficile disease has been studied by the application of many different typing or fingerprinting methods; these, and the lessons learned, are reviewed herein.

Clostridioides difficile↗