1887

Abstract

SUMMARY

Trimethoprim-resistant urinary isolates of , collected in 1982, were studied and the results compared with those obtained for isolates collected during the period 1979-1980. Ninety-eight (81%; a 10% increase) were resistant to trimethoprim 1024 µg/ml and 93 (95%) were also resistant to sulphamethoxazole 1024 µg/ml. The frequency distributions of plasmids were similar in both collections although there was a significant increase in the number of small plasmids (mol. wt ⩽ 20 × 10) in the 1982 collection. Transfer of resistance was associated with isolates that carried larger numbers of plasmids.

A significantly smaller proportion of isolates in this, than in the earlier series, transferred trimethoprim resistance to K12 suggesting continued transposition of trimethoprim resistance on to the bacterial chromosome. Fifteen different trimethoprim resistance plasmids were identified, of which five, including that found most frequently, were common to both collections. Plasmids which transferred trimethoprim resistance without sulphonamide resistance were more common in the 1982 series. Plasmids which transferred linked trimethoprim and streptomycin resistances, in particular those not carrying other resistance markers, were less common in the 1982 series of isolates. Although the majority of isolates highly resistant to trimethoprim remained resistant to sulphonamide, our results suggested changes in the genetic location and linkage of the resistance markers.

Loading

Article metrics loading...

/content/journal/jmm/10.1099/00222615-18-1-95
1984-08-01
2024-04-24
Loading full text...

Full text loading...

/deliver/fulltext/jmm/18/1/medmicro-18-1-95.html?itemId=/content/journal/jmm/10.1099/00222615-18-1-95&mimeType=html&fmt=ahah

References

  1. Amyes S. G. B. 1983; The detection and incidence of transferable trimethoprim resistance. Health Bulletin Edinburgh: 41:100–107
    [Google Scholar]
  2. Brumfitt W., Hamilton-Miller J. M. T., Gooding A. 1980; Resistance to trimethoprim. Lancet 1:1409–1410
    [Google Scholar]
  3. Brumfitt W., Hamilton-Miller J. M. T., Wood A. 1983; Evidence for a slowing in trimethoprim resistance during 1981-a comparison with earlier years. Journal of Antimicrobial Chemotherapy 11:503–509
    [Google Scholar]
  4. Datta N., Hughes V. M., Nugent M. E., Richards H. 1979; Plasmids and transposons and their stability and mutability in bacteria isolated during an outbreak of hospital infection. Plasmid 2:182–196
    [Google Scholar]
  5. Griineberg R. N., Bendall M. J. 1979; Hospital outbreak of trimethoprim resistance in pathogenic coliform bacteria. British Medical Journal 2:7–9
    [Google Scholar]
  6. Huovinen P., Toivanen P. 1981; Trimethoprim highly resistant, sulphonamide sensitive bacteria. Lancet 2:1235–1236
    [Google Scholar]
  7. Huovinen P., Mantyjarvi R., Toivanen P. 1982; Trimethoprim resistance in hospitals. British Medical Journal 284:782–784
    [Google Scholar]
  8. Kasanen A., Sundquist H. 1982; Trimethoprim alone in the treatment of urinary tract infections: eight years of experience in Finland. Reviews of Infectious Diseases 4:358–365
    [Google Scholar]
  9. Kraft C. A., Platt D. J., Timbury M. C. 1983; Distribution and transferability of plasmids in trimethoprim resistant urinary Escherichia coli. Journal of Medical Microbiology 16:433–441
    [Google Scholar]
  10. Lacey R. W. 1982; Do sulphonamide-trimethoprim combinations select less resistance to trimethoprim than the use of trimethoprim alone?. Journal of Medical Microbiology 15:403–427
    [Google Scholar]
  11. Shapiro J. A., Sporn P. 1977; Tn 402: a new transposable element determining trimethoprim resistance that inserts in bacteriophage lambda. Journal of Bacteriology 129:1632–1635
    [Google Scholar]
  12. Sherratt D. J. 1982; The maintenance and propagation of plasmid genes in bacterial populations. Journal of General Microbiology 128:655–661
    [Google Scholar]
  13. Siegel S. 1956 Non-parametric statistics for the behavioural sciences McGraw Hill Book Company Inc; London:
    [Google Scholar]
  14. Towner K. J. 1981; A clinical isolate of Escherichia coli owing its trimethoprim resistance to a chromosomally-located trimethoprim transposon. Journal of Antimicrobial Chemotherapy 7:157–162
    [Google Scholar]
  15. Towner K. J. 1982; Resistance to trimethoprim among urinary tract isolates in the United Kingdom. Reviews of Infectious Diseases 4:456–460
    [Google Scholar]
  16. Towner K. J., Venning B. M., Pinn P. A. 1982; Occurrence of transposable trimethoprim resistance in clinical isolates of Escherichia coli devoid of self-transmissible resistance plasmids. Antimicrobial Agents and Chemotherapy 21:336–338
    [Google Scholar]
  17. Towner K. J., Wise P. J. 1983; Transferable resistance plasmids as a contributory cause of increasing trimethoprim resistance in general practice. Journal of Antimicrobial Chemotherapy 11:33–39
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/jmm/10.1099/00222615-18-1-95
Loading
/content/journal/jmm/10.1099/00222615-18-1-95
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error