[Isolation of enteroaggregative escherichia coli (EAggEC) from patients with diarrheal disease in an outbreak case of overseas tour].
Twenty four patients out of 78 Cambodia tourists (31%) suffered from diarrhea and/or abdominal pain. Though the stools of 20 patients were examined in some local health centers and institutes, well-known pathogens were detected in only a low level and the cause of the outbreak remained unclear. We suspected the enteroaggregative Escherichia coli (EAggEC) as a cause of this outbreak. We examined E. coli strains isolated from stools of 8 patients (Okayama:7, Aichi:1) at first by the PCR method targeted both the aggR and the astA genes related to the virulence factors of EAggEC. As a result, the E. coli strains with positive aggR and/or astA genes were isolated from 8 patients. And the E. coli strains with positive both aggR gene and clump formation isolated from 3 patients adhered aggregatively to HEp-2 cells and accordingly identified as EAggEC. The plasmid profiles, PFGE patterns and drug resistance patterns of these EAggECs agreed completely. From these results, we concluded that at least 3 patients were infected with EAggEC of the same origin. Though we could not examine all samples from 20 patients, it is possible that the still uncommon EAggEC might be a cause of the outbreak. The E. coli strains with positive aggR gene did not always aggregatively adhered to HEp-2 cells. So we recommend to perform stepwise EAggEC screening tests by the PCR and the clump formation, and final confirmation test by the aggregative adhesion to HEp-2 cells.
Nakajima
Hiroshi
H
Department of Bacteriology, Okayama Prefectural Institute for Environmental Science and Public Health.
Yamazaki
Mitsugu
M
Kariya
Hideaki
H
Ohata
Ritsuko
R
D002160:Cambodia; D003967:Diarrhea / Q000382:microbiology*; D004196:Disease Outbreaks; D004926:Escherichia coli / Q000737:chemistry / Q000302:isolation & purification*; D004927:Escherichia coli Infections / Q000382:microbiology*; D029968:Escherichia coli Proteins / Q000302:isolation & purification*; D006801:Humans; D015534:Trans-Activators / Q000302:isolation & purification*; D014195:Travel
C088603:AggR protein, E coli; D029968:Escherichia coli Proteins; D015534:Trans-Activators