Jpn.J.Infect.Dis., 52, 33-37, 1999

Original Article

A Clinical and Bacteriological Study of Children Suffering from Haemolytic Uraemic Syndrome in Tucman, Argentina

Susana Miceli³, Maria Angela Jure^1,2, Olga A de Saab¹, Marta C de Castillo^1,*, Susana Rojas³, Aida P de Ruiz Holgado^1,2 and Olga M de Nader¹

¹Instituto de Microbiologia, Facultad de Bioquimica, Quimica y Farmacia,Universidad Nacional de Tucuman (UNT), Ayacucho 471, (4000) S.M. de Tucuman, Argentina, ²CERELA (Centro de Referencias para Lactobacilos) (Lactobacillus Reference Centre), Chacabuco 145, (4000) S.M. de Tucuman, Argentina and ³Servicio de Nefrologia, Hospital del Nino Jesus (Nephrology Department, Children's Hospital), Tucuman, Argentina

(Received October 6, 1998. Accepted March 23, 1999)

SUMMARY: Haemolytic uraemic syndrome (HUS) is a disease with serious consequences for children, such as terminal chronic renal failure. During the last few years there have been numerous studies undertaken to determine whether there is a relationship between this disease and the presence of Shiga toxin-producing bacteria. Escherichia coli (E. coli) O157:H7 is one of the most frequent etiologic agents of HUS. It acts through cytotoxins called Shiga toxin 1 (Stx1) and/or Shiga toxin 2 (Stx2) and carries a 90-Kb plasmid codified for an adhesion fimbria which is part of its pathogenicity. The objectives of this study were to: 1) confirm whether there exists a relationship between severity and clinical presentation of HUS; 2) prove the existence of Stx1 and/or Stx2 in the faeces of HUS patients; and 3) detect the presence of Stx1- and/or Stx2-producing E. coli. Our results did not show any difference in the average age, sex or clinical behavior between children with diarrhea positive (D+) HUS and diarrhea negative (D-) HUS. Male patients were predominant, as was incidence during summer, considering all cases. Nor could we find any relationship between severity and HUS type. E. coli O157:H7 was isolated in 40% of the patients with (D+) HUS and in 50% of patients with (D-) HUS. Another serotype, O55:K59, was also isolated (7%). Stx1 and/or Stx2 were found in all HUS cases. The following virulence factors of E. coli strains isolated from 12 patients were found: Adhesion fimbria (100%), Stx1 (16%), Stx2 (32%), and Stx1 + Stx2 (50%). None of these factors was found in control patients. Sixty-three percent of the HUS cases showed seroconversion for lipopolysaccharides of E. coli O157. We drew the following conclusions: 1) there is no significant relationship between seriousness of HUS and type of disease; 2) an association exists between HUS and the production of Stx1 and Stx2; 3) the incidence of E. coli O157:H7 was high in Tucuman, Argentina; and 4) Stx2 alone or in association with Stx1 was the predominant toxin.

*Corresponding author: Address: Avenida J.B. Justo 1192, (4000) S.M. de Tucuman, Argentina, Fax: +54-381-424 8169

Go to JJID Homepage                                      Go to JJID 52(2)