La prise en charge endoscopique du reflux vésico-urétéral (RVU) de l’enfant par injection acide de dextranomer/hyaluronique (Dx/Ha, Deflux^®) se complique dans moins de 0,6 % des cas d’une obstruction urétérale nécessitant une reprise chirurgicale. Dans la majorité des cas, cela survient lors de la période postopératoire immédiate. Nous présentons ici le cas d’un garçon de neuf ans ayant une obstruction urétérale distale à plus de deux ans du geste chirurgical initial. C’est le deuxième cas d’obstruction symptomatique retardée en raison de Dx/Ha rapporté dans la littérature.

Surgically relevant obstruction after dextranomer/hyaluronic acid injection (Dx/Ha, Deflux^®) for the treatment of vesicoureteral reflux (VUR) is rare with a 0.6% incidence. It occurs usually during the early postoperative period. We report here the case of a 9-year-old boy with a history of VUR who was previously treated with Deflux^® and was referred more than 2 years later with acute flank pain (as he already did 2weeks after surgery with a spontaneous relief under medical treatment). Initial radiological investigations showed hydronephrosis caused by distal ureteral obstruction which required open surgery removal of the Dx/Ha and Cohen procedure. This is the second case of delayed symptomatic obstruction due to Dx/Ha reported in the literature.