1887

Abstract

Verocytotoxin-producing O157 (O157 VTEC) has become well recognised as an important enteric pathogen. The number of organisms present in environmental and clinical samples may be low and efforts have been made to increase the sensitivity of O157 VTEC detection. Immunomagnetic separation (IMS) has been shown to improve O157 VTEC detection in bovine faeces and food samples. A milk-borne outbreak of O157 VTEC infection allowed us to compare the isolation rates from human faeces by IMS, direct faecal culture on sorbitol-MacConkey agar and a PCR test for verotoxin gene carriage. Of 142 faecal samples examined, 20 were positive on both direct culture and IMS and a further 13 on IMS alone. Therefore, IMS increased the detection rate of individual cases of O157 VTEC infection and also compared well with PCR. We recommend IMS for use in routine diagnostic laboratories where a more sensitive method than direct faecal culture is required for O157 VTEC isolation.

Loading

Article metrics loading...

/content/journal/jmm/10.1099/00222615-44-3-219
1996-03-01
2022-10-01
Loading full text...

Full text loading...

/deliver/fulltext/jmm/44/3/medmicro-44-3-219.html?itemId=/content/journal/jmm/10.1099/00222615-44-3-219&mimeType=html&fmt=ahah

References

  1. Riley L. W., Rimis R. S., Helgerson S. D. Hemorrhagic colitis associated with a rare Escherichia coli serotype. N Engl J Med 1983; 308:681–685
    [Google Scholar]
  2. Karmali M. A., Petrie M., Steele B. T., Lim C. Sporadic cases of haemolytic uraemic syndrome associated with faecal cytotoxin and cytotoxin-producing Escherichia coli in stools. Lancet 1983; 1:619–620
    [Google Scholar]
  3. Gross R. J. Escherichia coli diarrhoea. In Smith G. R., Easmon C. S. F. (eds) Topley and Wilson’s Principles of bacteriology, virology and immunity 8th edn London: Hodder and Stoughton; 1990469–487
    [Google Scholar]
  4. March S. B., Ratnam S. Sorbitol MacConkey medium for the detection of Escherichia coli O157:H7 associated with haemorrhagic colitis. J Clin Microbiol 1986; 23:869–872
    [Google Scholar]
  5. Chapman P. A. Evaluation of commercial latex slide test for identifying Escherichia coli O157. J Clin Pathol 1989; 42:1109–1110
    [Google Scholar]
  6. March S. B., Ratnam S. Latex agglutination test for the detection of Escherichia coli serotype O157. J Clin Microbiol 1989; 27:1675–1677
    [Google Scholar]
  7. Konowalchuk J., Spiers J. I., Stavric S. Vero response to a cytotoxin of Escherichia coli . Infect Immun 1977; 18:775–779
    [Google Scholar]
  8. Scotland S. M., Rowe B., Smith H. R., Willshaw G. A., Gross R. J. Verocytotoxin-producing strains of Escherichia coli from children with haemolytic uraemic syndrome and their detection by specific DNA probes. J Med Microbiol 1988; 25:237–243
    [Google Scholar]
  9. Chapman P. A. Isolation, identification and typing of verocytotoxin-producing Escherichia coli O157. PHLS Microbiology Digest 1994; 11:13–17
    [Google Scholar]
  10. Chapman P. A., Siddons C. A., Zadik P. M., Jewes L. An improved selective medium for the isolation of Escherichia coli O157. J Med Microbiol 1991; 35:107–110
    [Google Scholar]
  11. Zadik P. M., Chapman P. A., Siddons C. A. Use of tellurite for the selection of verocytotoxigenic Escherichia coli O157. J Med Microbiol 1993; 39:155–158
    [Google Scholar]
  12. Ritchie M., Partington S., Jessop J., Kelly M. T. Comparison of a direct shiga-like toxin assay and sorbitol MacConkey agar culture for laboratory diagnosis of enterohaemorrhagic Escherichia coli infection. J Clin Microbiol 1992; 30:461–464
    [Google Scholar]
  13. Paton A. W., Paton J. C., Goldwater P. N., Manning P. A. Direct detection of Escherichia coli shiga-like toxin genes in primary faecal cultures by polymerase chain reaction. J Clin Microbiol 1993; 31:3063–3067
    [Google Scholar]
  14. Chapman P. A., Wright D. J., Siddons C. A. A comparison of immunomagnetic separation and direct culture for the isolation of verocytotoxin-producing Escherichia coli O157 from bovine faeces. J Med Microbiol 1994; 40:424–427
    [Google Scholar]
  15. Chapman P. A., Wright D. J., Higgins S. R. Untreated milk as a source of verotoxigenic Escherichia coli O157. Vet Rec 1993; 133:171–172
    [Google Scholar]
  16. Wright D. J., Chapman P. A., Siddons C. A. Immunomagnetic separation as a sensitive method for isolating Escherichia coli O157 from food samples. Epidemiol Infect 1994; 113:31–39
    [Google Scholar]
  17. Okrend A. J. G., Rose B. E., Lattuada C. P. Isolation of Escherichia coli O157:H7 using O157 specific antibody coated magnetic beads. J Food Protect 1992; 55:214–217
    [Google Scholar]
  18. Mortlock S. Recovery of Escherichia coli O157:H7 from mixed suspensions: evaluation and comparison of pre-coated immunomagnetic beads and direct plating. Br J Biomed Sci 1994; 51:207–214
    [Google Scholar]
  19. Upton P., Coia J. E. Outbreak of Escherichia coli O157 infection associated with a pasteurised milk supply. Lancet 1994; 344:1015
    [Google Scholar]
  20. Pollard D. R., Johnson W. M., Lior H., Tyler S. D., Rozee K. R. Rapid and specific detection of verotoxin genes in Escherichia coli by the polymerase chain reaction. J Clin Microbiol 1990; 28:540–545
    [Google Scholar]
  21. Tarr P. I., Neill M. A., Clausen C. R., Watkins S. L., Christie D. L., Hickman R. O. Escherichia coli O157:H7 and the haemolytic uraemic syndrome: importance of early cultures in establishing the etiology. J Infect Dis 1990; 162:553–556
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/jmm/10.1099/00222615-44-3-219
Loading
/content/journal/jmm/10.1099/00222615-44-3-219
Loading

Data & Media loading...

Most cited this month Most Cited RSS feed

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