Escherichia coli 0157 : H7 strains that express Shiga toxin (Stx) 2 alone are more neurotropic for gnotobiotic piglets than are isotypes producing only Stx1 or both Stx1 and Stx2
A. Donohue-rolfe et al., Escherichia coli 0157 : H7 strains that express Shiga toxin (Stx) 2 alone are more neurotropic for gnotobiotic piglets than are isotypes producing only Stx1 or both Stx1 and Stx2, J INFEC DIS, 181(5), 2000, pp. 1825-1829
Infection with Escherichia coli O157:H7 can lead to hemolytic uremic syndro
me (HUS) in some children. Epidemiologic data suggest that Shiga toxin (Stx
) 2-producing strains are more frequently associated with HUS than are Stx1
-producing strains. Less clear is whether strains that express Stx2 alone a
re more frequently associated with HUS than strains that express Stx1 and S
tx2, Isogenic mutants 933stx1(-) and 933stx2(-) were produced from strain 9
33 (Stx1 and Stx2 producer), and 86-24stx2(-) was produced from strain 86-2
4 (Stx2 producer). Neurologic lesions or symptoms developed in 18 (90%) of
20 gnotobiotic piglets orally infected with strain 86-24, in 15 (85%) of 18
infected with mutant 933stx1(-), in 9 (31%) of 29 infected with strain 933
, in 0 of 5 infected with mutant 86-24stx2(-), and in 0 of 6 infected with
mutant 933stx2(-). Tt was concluded that strains expressing Stx2 alone are
more neurotropic for piglets when fed orally than are those strains express
ing Stx1 and 2, whereas Stx1-producing strains induce only diarrhea. It is
also conceivable that strains that produce Stx2 may constitute a significan
t predictive risk factor for HUS in humans.