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Evaluation of numerical typing systems for Escherichia coli using the API 50 CH and the PhP-EC systems as models*

Published online by Cambridge University Press:  15 May 2009

I. Kühn ,
A. Brauner  and
R. Möllby
I. Kühn
Affiliation:
Department of Bacteriology, Karolinska Institute, S-104 01 Stockholm, Sweden Department of Bacteriology, National Bacteriological Laboratory, S-105 21, Stockholm, Sweden
A. Brauner
Affiliation:
Department of Clinical Bacteriology, Stockholm City Council Central Microbiological Laboratory and Karolinska Hospital, S-107 26 Stockholm, Sweden
R. Möllby
Affiliation:
Department of Bacteriology, Karolinska Institute, S-104 01 Stockholm, Sweden
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Summary

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Reproducible and discriminating typing methods are required for epidemio-logical investigations. Numerical typing systems analyse patterns obtained in various ways by calculating similarity coefficients between isolates. In the present study, various measures of the efficiency of a numerical typing system are quantified. These include reproducibility, accuracy, and discrimination power.

Three different numerical typing methods for Escherichia coli were compared using these measures: (a) Biotyping with API 50 CH system, (b) Biochemical fingerprinting with the API 50 CH system and (c) Biochemical fingerprinting with the PhP-EC system. Biotyping qualitatively measures the results of a set of biochemical reactions as + or −. Biochemical fingerprinting also uses biochemical reactions, but the tests are scored quantitatively by measuring the kinetics and intensity of each reaction.

It was found that biotyping yielded poor reproducibility. When biochemical fingerprinting analysis was used with the API 50 CHE system the reproducibility and the discrimination was good. The PhP-EC system for biochemical fingerprinting showed equal reproducibility but was superior to the API 50 CH system with regard to discrimination power.

Type
Research Article
Information
Epidemiology & Infection , Volume 105 , Issue 3 , December 1990 , pp. 521 - 531
Copyright
Copyright © Cambridge University Press 1990

References

REFERENCES

1.Ørskov, F, Ørskov, I, Jann, B, Jann, K. Serology, chemistry, and genetics of O and K antigens of Escherichia coli. Bacteriol Rev 1977; 41: 667–710.CrossRefGoogle Scholar
2.Ørskov, F. Genus Escherichia. In: Kreig, NR, eds. Bergey's manual of systematic bacteriology. Baltimore: Williams and Wilkins, 9th ed, 1984 (1).Google Scholar
3.Gargan, R, Brumfitt, W, Hamilton-Miller, JMT. A concise biotyping system for differentiating strains of Escherichia coli. J Clin Pathol 1982; 35: 1366–1369.Google Scholar
4.Jackman, P. Microbial identification and systematics based on whole-cell protein patterns. In: Sanna, A, Morace, G, eds, New horizons in microbiology. Elsevier Science Publisher B.V. 1984: 71–8.Google Scholar
5.Achtman, M, Mercer, A, Kusecek, B et al. , Six widespread bacterial clones among Escherichia coli K1 isolates. Infect Immun 1983; 39: 315–35.Google Scholar
6.Achtman, M, Pluschke, G. Clonal analysis of descent and virulence among selected Escherichia coli. Ann Rev Microbiol 1986; 40: 185–210.Google Scholar
7.Crichton, PB, Old, DC. Biotyping of Escherichia coli. J Med Microbiol 1979; 12: 473–86.Google Scholar
8.Crichton, P, Old, DC. A biotyping scheme for the subspecific discrimination of Escherichia coli. J Med Microbiol 1982; 223–42.Google Scholar
9.Okerman, L, Devriese, LA. Biotypes of enteropathogenic Escherichia coli strains from rabbits. J Clin Microbiol 1985; 22: 955–58.CrossRefGoogle ScholarPubMed
10.Godbout-Delasalle, F, Higgins, R. Biotyping of clinical isolates of Escherichia coli of animal origin, using the API 20E system. Can J Vet Res 1986; 50: 418–21.Google ScholarPubMed
11.Cicmanec, JF, Evans, AT. Classification of urinary tract infections by biotype identification of the pathogens. J Urology 1979; 124: 68–9.Google Scholar
12.Brauner, AL, Boeufgras, JM, Jacobson, SH, Kaijser, B, Källenius, G, Svenson, SB, Wretlind, B. The use of biochemical markers, serotype and fimbriation in the detection of Escherichia coli clones. J Gen Microbiol 1987; 133: 2825–34.Google ScholarPubMed
13.Kühn, I. Biochemical fingerprinting of Escherichia coli. A simple method for epidemiological investigations. J Microbiol Meth 1985; 3: 159–70.CrossRefGoogle Scholar
14.Kühn, I, Burman, L, Ericsson, L, Möllby, R. Subtyping of Klebsiella by biochemical fingerprinting. A simple system for epidemiological investigations. J Microbiol Meth 1990; 11: 177–85.Google Scholar
15.Brauner, A, Hylander, B, Wretlind, B, Östenson, CG, Kühn, I. Escherichia coli populations from diabetic and non-diabetic patients with bacteraemia and faecal samples from healthy subjects-a comparative study. Epidemiol Infect 1990; 105: 533–40.Google Scholar
16.Sneath, PHA, Sokal, RR. Numerical taxonomy. San Francisco: W. H. Freeman and Company, 1973.Google Scholar
17.Hunter, PR, Gaston, MA. Numerical index of the discriminatory ability of typing systems: An application of Simpson's index of diversity. J Clin Microbiol 1988; 26: 2465–6.Google Scholar
18.Kühn, I, Franklin, A, Söderlind, O, Möllby, R. Phenotypic variations among enterotoxino-genic O-groups of Escherichia coli from Swedish piglets with diarrhoea. Med Microbiol Immun 1985; 174: 119–30.CrossRefGoogle ScholarPubMed
19.Kühn, I, Möllby, R. (1986) Phenotypic variations among enterotoxinogenic O-groups of Escherichia coli from various human populations. Med Microbiol Immun 1986; 175: 15–26.Google Scholar
20.Kühn, I, Tullus, K, Möllby, R. Colonization and persistence of Escherichia coli phenotypes in the intestines of children aged 0 to 18 months. Infection 1986; 14: 7–16.CrossRefGoogle Scholar
21.Old, DC, Barker, RM. Numerical index of the discriminatory ability of biotyping for strains of Salmonella typhimurium and Salmonella paratyphi B. Epidemiol Infect 1989; 103: 435–43.Google Scholar
22.Crichton, P, Old, DC. Biotyping of Escherichia coli: methods and applications. In: Sussman, M, ed. The virulence of Escherichia coli: reviews and methods. London: Academic Press, Inc., 1985.Google Scholar
23.Katouli, M, Kühn, I, Möllby, R. Evaluation of the stability of biochemical phenotypes of Escherichia coli upon subculturing and storage. J Gen Microbiol. In Press.Google Scholar