The authors report the case of a 16 year-old boy admitted for the seve
nth acute occurrence in 18 months of abdominal pain associated with hy
pereosinophilia. Each episode was identical in nature and receded spon
taneously after 5 or 6 days. Biopsy of a fiber colonoscopically obtain
ed specimen of small intestin was performed The diagnosis of eosinophi
lic gastroenteritis was based upon art infiltration of the digestive m
ucosa by eosinophils, the absence of elements in favor of other types
of digestive-tract disease (parasitic, allergic hematologic, or inflam
matory), and the absence or other illness outside the digestive system
. However, the incidental discovery of a distal dilation of both of th
e patient's ureters during one such episode, that disappeared with the
other symptoms, mises the possibility of a bladder location as well,
and thus of a hypereosinophilic syndrome. Corticoids were administered
then tapered down. A relapse occurred 2 months later Currently, he is
taking 20 mg of a corticoid every other day and has presented no mani
festations over the last 9 months.