Association of IL-8-inducing strains of diffusely adherent Escherichia coli with sporadic diarrheal patients with less than 5 years of age.
The role of diffusely adherent Escherichia coli (DAEC) in diarrheal disease has been controversial. However, DAEC strains were recently implicated in diarrheal disease in developing countries. To clarify whether DAEC are prevalent among sporadic cases of diarrheal illness in Osaka City, Japan, E. coli strains isolated between July 1997 and March 2000 during diarrheagenic E. coli (DEC) investigation were retrospectively examined. DAEC strains were recognized among 41 (4.4%) of 924 patients and formed the biggest subgroup of DEC. Previously, we reported that some DAEC strains caused epithelial cells to secrete as much IL-8 as enteroaggregative E. coli strains did. In this study, we attempted to evaluate epidemiologically whether the ability of DAEC to induce IL-8 was involved in the pathogenesis. Relationship among patient age, symptoms, Afa adhesins, season and IL-8 induction were examined. The subgroup of DAEC that possessed Afa genes and/or induced a high level of IL-8 was significantly prevalent among patients age 1 to 4 years; however total DAEC was not significantly high among the children compared to other age group. IL-8 inducing DAEC seems to play a role in causing sporadic diarrheal illnesses, particularly in pediatric fields. Investigations highlighting the relationship between IL-8 induction and enteropathogenicity are clearly necessary to confirm the role of DAEC in infectious enteritis.
Meraz
Ismail Mustafa
IM
Department of Food and Human Health Sciences, School of Human Life Science, Osaka City University, Osaka, Japan.
Arikawa
Kentaro
K
Nakamura
Hiromi
H
Ogasawara
Jun
J
Hase
Atsushi
A
Nishikawa
Yoshikazu
Y
D018830:Adhesins, Escherichia coli / Q000235:genetics* / Q000502:physiology; D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D001422:Bacterial Adhesion; D002648:Child; D002675:Child, Preschool; D003967:Diarrhea / Q000453:epidemiology / Q000382:microbiology*; D004926:Escherichia coli / Q000235:genetics / Q000472:pathogenicity*; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000378:metabolism / Q000382:microbiology*; D005243:Feces / Q000382:microbiology; D005260:Female; D006801:Humans; D007223:Infant; D016209:Interleukin-8 / Q000378:metabolism*; D007422:Intestines / Q000166:cytology / Q000276:immunology / Q000382:microbiology; D007564:Japan / Q000453:epidemiology; D008297:Male; D015995:Prevalence; D012189:Retrospective Studies; D012621:Seasons
D018830:Adhesins, Escherichia coli; D016209:Interleukin-8