Abstract
Enteropathogenic Escherichia coli (EPEC) strains designated on the basis of their serotypes are epidemiologically associated with diarrhea. They adhere to the intestinal mucosa, producing the characteristic attaching and effacing (AE) lesion in an in vitro organ culture system. EPEC manifest localized adherence (LA) in the HEp-2 cell assay, and this is commonly used for clinical diagnosis. Recently, the fluorescence actin staining (FAS) test was proposed for the identification of E. coli causing the AE lesion. We therefore compared the FAS test with the HEp-2 cell assay and the EPEC adherence factor (EAF) probe assay for the detection of EPEC strains. Among 240 stool samples from children with diarrhea examined, 176 yielded E. coli and 14 of these strains showed the LA pattern in the HEp-2 cell assay; 11 of these were positive by both the EAF and the FAS tests. By using the HEp-2 cell assay as the "gold standard," the FAS test gave a sensitivity of 78.5% and a specificity of 100%. The three localized adherent FAS-negative strains tested subsequently were positive by the enteroaggregative E. coli DNA Probe and failed to produce the AE lesions characteristic of EPEC. When these strains were not considered, the sensitivity of the FAS test for detecting isolates that manifest LA was 100%. Against the EAF probe, the sensitivity and specificity of the FAS test were 91.6 and 100%, respectively. The FAS test avoids infrequent but nevertheless important phenotypic misclassifications in the HEp-2 cell assay, and it may therefore serve as a confirmatory test for EPEC.
Full text
PDF
Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Baudry B., Savarino S. J., Vial P., Kaper J. B., Levine M. M. A sensitive and specific DNA probe to identify enteroaggregative Escherichia coli, a recently discovered diarrheal pathogen. J Infect Dis. 1990 Jun;161(6):1249–1251. doi: 10.1093/infdis/161.6.1249. [DOI] [PubMed] [Google Scholar]
- Bhan M. K., Raj P., Levine M. M., Kaper J. B., Bhandari N., Srivastava R., Kumar R., Sazawal S. Enteroaggregative Escherichia coli associated with persistent diarrhea in a cohort of rural children in India. J Infect Dis. 1989 Jun;159(6):1061–1064. doi: 10.1093/infdis/159.6.1061. [DOI] [PubMed] [Google Scholar]
- Jerse A. E., Gicquelais K. G., Kaper J. B. Plasmid and chromosomal elements involved in the pathogenesis of attaching and effacing Escherichia coli. Infect Immun. 1991 Nov;59(11):3869–3875. doi: 10.1128/iai.59.11.3869-3875.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Knutton S., Baldwin T., Williams P. H., McNeish A. S. Actin accumulation at sites of bacterial adhesion to tissue culture cells: basis of a new diagnostic test for enteropathogenic and enterohemorrhagic Escherichia coli. Infect Immun. 1989 Apr;57(4):1290–1298. doi: 10.1128/iai.57.4.1290-1298.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Knutton S., Phillips A. D., Smith H. R., Gross R. J., Shaw R., Watson P., Price E. Screening for enteropathogenic Escherichia coli in infants with diarrhea by the fluorescent-actin staining test. Infect Immun. 1991 Jan;59(1):365–371. doi: 10.1128/iai.59.1.365-371.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nataro J. P., Baldini M. M., Kaper J. B., Black R. E., Bravo N., Levine M. M. Detection of an adherence factor of enteropathogenic Escherichia coli with a DNA probe. J Infect Dis. 1985 Sep;152(3):560–565. doi: 10.1093/infdis/152.3.560. [DOI] [PubMed] [Google Scholar]
- Nataro J. P., Kaper J. B., Robins-Browne R., Prado V., Vial P., Levine M. M. Patterns of adherence of diarrheagenic Escherichia coli to HEp-2 cells. Pediatr Infect Dis J. 1987 Sep;6(9):829–831. doi: 10.1097/00006454-198709000-00008. [DOI] [PubMed] [Google Scholar]
- Ulshen M. H., Rollo J. L. Pathogenesis of escherichia coli gastroenteritis in man--another mechanism. N Engl J Med. 1980 Jan 10;302(2):99–101. doi: 10.1056/NEJM198001103020207. [DOI] [PubMed] [Google Scholar]
- Vial P. A., Robins-Browne R., Lior H., Prado V., Kaper J. B., Nataro J. P., Maneval D., Elsayed A., Levine M. M. Characterization of enteroadherent-aggregative Escherichia coli, a putative agent of diarrheal disease. J Infect Dis. 1988 Jul;158(1):70–79. doi: 10.1093/infdis/158.1.70. [DOI] [PubMed] [Google Scholar]