Previous Article | Next Article ![]()
Journal of Clinical Microbiology, November 2000, p. 4108-4113, Vol. 38, No. 11
Department of Microbiology, Sunnybrook and
Women's College Health Sciences Centre,1
and the University of Toronto,2
Toronto, Ontario, Canada
Received 1 June 2000/Returned for modification 30 June
2000/Accepted 28 August 2000
Rapid identification of Escherichia coli O157:H7 is
important for patient management and for prompt epidemiological
investigations. We evaluated one in-house method and three commercially
available kits for their ability to extract E. coli O157:H7
DNA directly from stool specimens for PCR. Of the 153 stool specimens
tested, 107 were culture positive and 46 were culture negative. The
sensitivities and specificities of the in-house enrichment method,
IsoQuick kit, NucliSens kit, and QIAamp kit were comparable, as
follows: 83 and 98%, 85 and 100%, 74 and 98%, and 86 and 100%,
respectively. False-negative PCR results may be due to the presence of
either inherent inhibitors or small numbers of organisms. The presence of large amounts of bacteria relative to the amount of the E. coli O157:H7 target may result in the lower sensitivities of the assays. All commercial kits were rapid and easy to use, although DNA
extracted with the QIAamp kit did not require further dilution of the
DNA template prior to PCR.
0095-1137/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.
PCR Detection of Escherichia coli O157:H7 Directly
from Stools: Evaluation of Commercial Extraction Methods for
Purifying Fecal DNA
*
Corresponding author. Mailing address: Department of
Microbiology, Sunnybrook and Women's College Health Sciences Centre, Rm. B1-21, 2075 Bayview Ave., Toronto, Ontario, Canada M4N 3M5. Phone:
(416) 480-4253. Fax: (416) 480-6845.
This article has been cited by other articles:
| Antimicrob. Agents Chemother. | Clin. Microbiol. Rev. |
|---|---|
| Clin. Vaccine Immunol. | ALL ASM JOURNALS |
|---|