Verocytotoxigenic Escherichia coli serologic responses in patients with hemolytic uremic syndrome.

To the Editor—We read with interest the recent paper by Jelacic et al. [1], in which they unsuccessfully sought a link between ABO and P1 blood groups and outcomes of childhood infections by Escherichia coli O157. We would like to draw readers’ attention to our observations during an outbreak of hemolytic-uremic syndrome (HUS), in which we compared the numbers of seroreactivities to potential enterohemorrhagic E. coli (EHEC)–related E. coli O antigens versus the total complications and the mean total complication score as determined clinically by an independent observer. Our results clearly show that, as the number of complications increased or as the complication score increased, all mean seroreactivities also increased [2, 3]. This strongly supports the conclusion that multiple infections with a variety of verocytotoxigenic E. coli (VTEC) contributed to the outbreak. It also appears that the larger the variety of infecting VTEC, the greater the possibility of complication. We do not doubt the significance of EHEC O157 as an important cause of HUS and other human infections; however, until such infections are thoroughly investigated—including testing for the presence of non-O157 VTEC, which are known to be present on meat derived from ruminant animals [4–6]—false interpretations are likely.