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M Cormican

Publications and source records attributed to M Cormican.

32 records · Page 2Linked to original sources
PubMed2000

Molecular characterization of Irish Salmonella enterica serotype typhimurium: detection of class I integrons and assessment of genetic relationships by DNA amplification fingerprinting.

Salmonella enterica is among the principal etiological agents of food-borne illness in humans. Increasing antimicrobial resistance in S. enterica is a cause for worldwide concern. There is concern at present in relation to the increasing incidence of human infection with antimicrobial agent-resistant strains of S. enterica serotype Typhimurium, in particular of phage type DT104. Integrons appear to play an important role in the dissemination of antimicrobial resistance genes in many Enterobacteriaceae including S. enterica. In this study the antimicrobial susceptibilities and phage types of 74 randomly collected strains of S. enterica serotype Typhimurium from the Cork region of southern Ireland, obtained from human, animal (clinical), and food sources, were determined. Each strain was examined for integrons and typed by DNA amplification fingerprinting (DAF). Phage type DT104 predominated (n = 48). Phage types DT104b (n = 3), -193 (n = 9), -195 (n = 6), -208 (n = 3), -204a (n = 2), PT U302 (n = 1), and two nontypeable strains accounted for the remainder. All S. enterica serotype Typhimurium DT104 strains were resistant to ampicillin, chloramphenicol, streptomycin, Sulfonamide Duplex, and tetracycline, and one strain was additionally resistant to trimethoprim. All DT104 strains but one were of a uniform DAF type (designated DAF-I) and showed a uniform pattern of integrons (designated IP-I). The DT104b and PT U302 strains also exhibited the same resistance phenotype, and both had the DAF-I and IP-I patterns. The DAF-I pattern was also observed in a single DT193 strain in which no integrons were detectable. Greater diversity of antibiograms and DAF and IP patterns among non-DT104 phage types was observed. These data indicate a remarkable degree of homogeneity at a molecular level among contemporary isolates of S. enterica serotype Typhimurium DT104 from animal, human, and food sources in this region.

Animals↗
PubMed1999

Cost-effective methods for isolation of Salmonella enterica in the clinical laboratory.

Data from 8,717 fecal specimens indicate that primary inoculation of xylose lysine deoxycholate (XLD) agar may enhance the speed, but not the sensitivity, of isolation of Salmonella enterica over that achieved with Selenite enrichment only. Plating of Selenite broth onto both brilliant green and XLD agar offers no advantage over plating onto XLD alone.

Agar↗
PubMed1998

Extended spectrum beta-lactamase production and fluorquinolone resistance in pathogens associated with community acquired urinary tract infection.

We have evaluated the susceptibility of 199 pathogens isolated in pure culture from consecutive urine samples submitted from the community. Rates of susceptibility for all organisms were ampicillin, 48%; amoxycillin/clavulanic acid, 88%; cephalothin, 57%; cefuroxime axetil, 74%; nalidixic acid, 85%; ciprofloxacin, 99%; nitrofurantoin, 78%; and trimethoprim, 67%. Ciprofloxacin resistance and production of extended spectrum beta-lactamase enzymes were detected in Escherichia coli strains isolated from patients in the community.

Anti-Infective Agents↗
PubMed1995

The sensitive detection of fluorescently labelled PCR products using an automated detection system.

The polymerase chain reaction plays a central role in many detection assays and methods to improve the sensitivity and specificity of these detection systems are constantly being explored. In this study we investigated the use of an automated laser fluorescent system (ALF) in the context of DNA-based diagnostics for pathogenic bacteria. PCR products were generated using species-specific primer sets, one of which was labelled with a 5' fluorescein. PCR products with a fluorescent label were detected on line with an ALF DNA sequencer and the sensitivity of detection was found to be comparable to that for DNA probe hybridization with a radioactive probe. The technology was successfully applied to the detection of Mycobacterium tuberculosis supplemented into sputum samples and to the detection of listeria in paraffin-embedded tissue samples.

Base Sequence↗
PubMed1995

Multiplex PCR for identifying mycobacterial isolates.

AIMS: To develop a multiplex polymerase chain reaction (PCR) method to facilitate identification of mycobacterial isolates. METHODS: Type strains of 14 species of mycobacteria and 56 clinical isolates were lysed by boiling in TE Triton. The lysate (5 microliters) was used directly in a PCR reaction incorporating three pairs of PCR primers expected to amplify fragments from the genome of (a) all mycobacteria, (b) Mycobacterium tuberculosis complex only and (c) M avium only. PCR products were visualised by electrophoresis on agarose gels. RESULTS: Multiplex PCR applied to 14 type strains yielded patterns on electrophoresis which permitted identification of the mycobacterial isolates as M tuberculosis complex, M avium or as mycobacteria other than the former. The identification of 56 clinical isolates by multiplex PCR was consistent with other methods and was accomplished in less than one working day. CONCLUSIONS: This method may facilitate rapid and convenient identification of most clinical isolates of mycobacteria by PCR and gel electrophoresis. Further evaluation is warranted.

Base Sequence↗
PubMed1994

The ribosomal intergenic spacer region: a target for the PCR based diagnosis of tuberculosis.

SETTING: DNA Diagnostics, The National Diagnostics Centre and University College Hospital, Galway, Republic of Ireland. OBJECTIVE: To investigate the possibility of developing a DNA probe to distinguish the members of the Mycobacterium tuberculosis complex and develop an assay for the detection of M. tuberculosis in sputum. DESIGN: The ribosomal intergenic spacer regions from the members of the M. tuberculosis complex were sequenced and analysed for the ability of this region to provide sequence diversity for DNA probe development. RESULTS: The 100% sequence homology in this region precluded the development of a probe to distinguish the individual members of the M. tuberculosis complex. However it was possible to develop a DNA probe that could specifically detect only the members of the M. tuberculosis complex. CONCLUSION: A specific DNA probe was developed for the detection of the M. tuberculosis complex and its application to M. tuberculosis detection in sputum was demonstrated.

Base Sequence↗
PubMed1993

A comparison of antimicrobial sensitivities of urinary pathogens for the years 1980 and 1990.

Urinary tract infection is a major cause of morbidity in both the hospital and community which often requires empirical therapy. We have retrospectively studied laboratory diagnosed urinary tract infections for the years 1980 and 1990 to document the common pathogens and antimicrobial susceptibility patterns. In 1990 a significantly lower proportion of specimens yielded Proteus sp. or Klebsiella sp. than was the case in 1980. This was true of specimens from both the hospital and the community. There was an increase in the proportion of specimens yielding Pseudomonas sp. and coagulase negative Staphylococci (CNS). Significant changes in the antimicrobial susceptibility of urinary pathogens are also noted. In particular a greater proportion of isolates from the community were sensitive to cephalothin in 1990, while fewer isolates were sensitive to nalidixic acid and gentamicin. A greater proportion of isolated from hospital practice were sensitive to ampicillin, to cephalothin and to trimethoprim in 1990 while fewer isolates were sensitive to gentamicin. In relation to nitrofurantoin no significant change was noted. In respect of isolates from both community and hospital practice the agents ofloxacin, co-amoxiclav (not available in 1980) and gentamicin are those which are most consistently active.

Anti-Bacterial Agents↗
PubMed1989

Ulcerative enteritis--atypical features.

A 40 year old man with two month history of vomiting and weight loss, was found to have multiple strictures in his small bowel. Investigations outruled known causes of small bowel ulceration, and the flat bowel mucosa did not respond to a gluten free diet. Treatment with steroids conferred a temporary benefit, however, small bowel ulceration persisted.

Adult↗
PubMedDate not supplied

In-vitro activity of piperacillin/tazobactam relative to other antibiotics against blood culture isolates.

Resistance of bacteria to antibiotics is an increasing problem in many countries. Accurate locally relevant information is essential for detection and control of emerging resistance and to facilitate choice of empirical antibiotic therapy in the immediate management of seriously ill patients. We have determined the minimum inhibitory concentration of piperacillin/tazobactam for 97 strains of bacteria (55 Enterobacteriaceae, 13 non-fermentative Gram-negative bacilli, 22 Staphylococcus aureus, 6 Enterococcus faecalis and 1 Bacillus cereus) isolated from blood cultures and compared its activity to that of amoxycillin, co-amoxiclav, cephalothin, cefotaxime, ceftazidime, ciprofloxacin, gentamicin, piperacillin, cefotaxime. The strains were consecutive non-fastidious isolates with the following qualifications: coagulase negative staphylococci and diphtheroids were excluded and the number of Staphylococcus aureus isolates was limited to 12 methicillin-resistant and 10 methicillin-sensitive strains. Multiple isolates of the same species from individual patients were not included. The minimum inhibition concentrations of methicillin, penicillin, teichoplanin and vancomycin were also determined for specific groups of organisms. MICs were determined by the Etest method (AB Biodisk, Solna, Sweden) on Mueller Hinton agar. The MICs of appropriate American Type Culture Collection control strains were determined. Based on the interpretative criteria of the National Committee for Clinical Laboratory Standards (USA), 87 per cent of Gram-negative bacilli were susceptible to piperacillin/tazobactam compared with amoxycillin 26 per cent, cephalothin 35 per cent, co-amoxiclav 54 per cent, piperacillin 56 per cent, cefotaxime 69 per cent, ceftazidime 84 per cent, gentamicin 85 per cent and ciprofloxacin 91 per cent. Of all isolates 75 per cent were sensitive to piperacillin/tazobactam, compared with amoxycillin 22 per cent, cephalothin 35 per cent, piperacillin 41 per cent, co-amoxiclav 52 per cent, cefotaxime 59 per cent, ceftazidime 60 per cent, gentamicin 74 per cent and ciprofloxacin 77 per cent. Two isolates (1 E. coli and 1 Klebsiella pneumoniae) with antibiograms consistent with the relatively new resistance phenomenon of extended spectrum beta-lactamase production were identified. The spectrum of activity of piperacillin-tazobactam for empirical antibiotic therapy is significantly greater than that of piperacillin alone and is similar to that of ciprofloxacin and gentamicin.

Anti-Bacterial Agents↗
PubMedDate not supplied

Transport of digested decontaminated sputum specimens to a central laboratory for testing for M. tuberculosis by Amplicor MTB test.

Rapid diagnosis of tuberculosis may improve management of infected patients and facilitate infection control procedures. The relatively slow growth rate of M. tuberculosis and the limited sensitivity and specificity of microscopy make rapid diagnosis difficult. Nucleic acid amplification techniques have been extensively studied for the detection of M. tuberculosis DNA and a number of commercial products for detection of M. tuberculosis nucleic acid in clinical specimens are now available. As performance of diagnostic PCR at central reference laboratories may be desirable, the impact of specimen transport on the performance of the Amplicor MTB PCR assay is of practical importance. We have assessed the performance of the Amplicor MTB PCR on specimens submitted and initially processed in laboratories in 3 cities and then transported to a single laboratory for PCR assay. The overall sensitivity of the PCR test was 97 per cent and the corrected specificity was 100 per cent. All of 23 culture positive specimens collected locally were PCR positive compared with 10 of 11 culture positive specimens transported from elsewhere. In this study transportation of digested decontaminated specimens to a central laboratory either frozen at -20 degrees, or overnight at room temperature had no apparent effect on the performance characteristic of the Amplicor MTB PCR assay.

Decontamination↗
PubMedDate not supplied

Antimicrobial resistance in E.coli associated with urinary tract infection in the west of Ireland.

BACKGROUND: Knowledge of antimicrobial resistance patterns in E. coli, the predominant pathogen associated with urinary tract infection (UTI) is important as a guide in selecting empirical antimicrobial therapy AIMS: To describe the antimicrobial susceptibility of E. coli associated with UTI in a region in the West of Ireland. METHODS: A collection of 934 E. coli isolates associated with UTI were tested for susceptibility to a panel of antimicrobial agents by the disc diffusion method of the National Committee for Clinical Laboratory Standards. RESULTS: More than 50% of E. coli were resistant to ampicillin, more than 40% resistant to sulphonamide and more than 30% resistant to trimethoprim. From 7.9% (community) to 12.5% (hospital) are resistant to co-amoxiclav with approximately 20% of isolates of intermediate susceptibility. In general practice most E. coli remain susceptible to nitrofurantoin (96.7%), nalidixic acid (93.9%) and ciprofloxacin (94.7%). For all agents rates of resistance were higher in hospital as compared with general practice isolates. Three isolates with the phenotype of Extended Spectrum Beta-lactamase (ESBL) resistance were detected. CONCLUSIONS: Ampicillin/amoxicillin are not suitable for empiric therapy of UTI in general practice or hospital patients in this region. There is doubt as to the role of trimethorpim or co-trimoxazole for empiric therapy of UTI. Nitrofurantoin, nalidixic acid and ciprofloxacin are active against the great majority of UTI associated E. coli.

Anti-Bacterial Agents↗