TABLE 2.
Sample ID | Clinical diagnosisa | Age | Serotypeb | Genotypic characterizationc
|
FFStxd
|
|||
---|---|---|---|---|---|---|---|---|
eae/ehx | stx | Vero cell cytotoxicity assay | Stx Quik Chek assay | VHH-based ELISA | ||||
1 | HUS | 3 mo | O145:NM | +/+ | stx2a | ND | Pos (Stx2) | Pos |
2 | BD | 6 yr | O145:NM | +/+ | stx2a | ND | Pos (Stx2) | Pos |
3 | BD | 13 mo | O157:H7 | +/+ | stx2a/2c | ND | Pos (Stx2) | Pos |
4 | BD | 1 yr | O145:NM | +/+ | stx2a | ND | Pos (Stx2) | Pos |
5 | HUS | 41 mo | O59:H19 | −/+ | stx2a | Pos | Pos (Stx2) | Pos |
6 | UFS | 10 mo | O26:H11 | +/+ | stx1a | ND | Pos (Stx1) | Neg |
7 | UFS | 1 mo | ONT:HNT | +/+ | stx1a | ND | Neg | Neg |
8 | HUS | 20 mo | O157:H7 | +/+ | stx2a/2c | ND | Pos (Stx2) | Pos |
9 | D | 7 yr | O121:HNT | +/+ | stx2a | ND | Pos (Stx2) | Pos |
10 | D | 11 yr | O145:NM | +/+ | stx2a | ND | Pos (Stx2) | Pos |
11 | D | 10 mo | O145:NM | +/+ | stx2a | ND | Pos (Stx2) | Pos |
12 | HUS | 18 mo | O145:NM | +/+ | stx2a | Neg | Neg | Neg |
13 | HUS | 2 yr | O157:H7 | +/+ | stx2a/2c | Neg | Neg | Neg |
14 | HUS | 11 mo | O157:H7 | +/+ | Neg | Neg | Neg | Neg |
15 | HUS | 21 mo | ONT:HNT | ND | Neg | Neg | Neg | Neg |
16 | HUS | 60 mo | ONT:HNT | ND | Neg | Neg | Neg | Neg |
17 | D | 3 yr | ONT:HNT | ND | Neg | ND | Neg | Neg |
18 | BD | 2 yr | ONT:HNT | ND | Neg | ND | Neg | Neg |
19 | D | 2 yr | ONT:HNT | ND | Neg | ND | Neg | Neg |
20 | BD | 11 mo | ONT:HNT | ND | Neg | ND | Neg | Neg |
21e | HUS | 2 yr | ONT:HNT | ND | Neg | Pos | Neg | Pos |
22 | BD | 3 mo | ONT:HNT | ND | Neg | ND | Neg | Neg |
HUS, hemolytic-uremic syndrome; BD, bloody diarrhea; D, diarrhea; UFS, unspecific febrile syndrome.
Serotype was determined by seroagglutination using specific antisera. ONT, O polysaccharide not typified; HNT, flagellar H antigen not typified; NM, not motile.
eae, ehxA, and stx gene(s) detection by PCR. ND, not determined.
Free fecal Shiga toxin (FFStx) detection in stool samples. Pos, positive; Neg, negative; ND, not determined; VHH-based ELISA, biotin-streptavidin VHH-based capture ELISA with spectrophotometric detection.
Bacterial isolation, negative; immunomagnetic separation for O157, negative; multiple PCR for rfbO157/stx1/stx2, negative; PCR for diarrheagenic Escherichia coli including enteropathogenic E. coli (eae), enteroaggregative E. coli (aggR), enteroinvasive E. coli (ipaH), and enterotoxigenic E. coli (heat-labile enterotoxin/heat-stable enterotoxin), negative; Chemlis E. coli O157, O145, and O121 (Chemtest Argentina S.A., detection of specific IgM and IgG antibodies in serum sample), negative.