Role of Yersinia enterocolitica-Reply

In Reply.—Chiesa et al are correct when stating that tests to place the Y enterocolitica isolated from our patient into a specific serogroup and biotype were not performed. My colleagues and I agree that knowing the serogroup and antibody response would be of interest; however, we do not think that it is necessary for confirming the diagnosis of Y enterocolitica gastroenteritis. In the study by Marks et al,¹ 545 asymptomatic children in their control group had cultures that were negative for Y enterocolitica of any serogroup. The 18 isolates of non-0:3 serogroups were obtained from children with gastroenteritis.¹ Asakawa et al² reported Y enterocolitica isolated from only 0.34% of 4,673 stool specimens of apparently healthy persons in Japan, an area where Yersinia infection is not uncommon. Clearly, the isolation of Y enterocolitica in the stool of asymptomatic persons is quite rare, and in our patient with