[Secondary megaureter: A rare complication of Deflux endoscopic management of vesicoureteral reflux in children].

Endoscopic management is the gold standard for symptomatic low-grade vesicoureteral reflux (VUR) in children. Deflux (hyaluronic acid/dextranomer) injection is highly effective and has very few complications. We report on two cases of secondary megaureter after Deflux injections. In the first case, a boy presented with Grade 4 VUR. He received a bilateral Deflux injection with a total of three syringes. The postoperative ultrasound was normal. However, a check-up ultrasound 3 years later showed a significant ureteropyelocalyceal dilatation, with stasis and decreased renal function on scintigraphy, the reason why antireflux surgery (Cohen procedure) was performed. In the second case, a girl diagnosed with bilateral VUR at birth received bilateral injections with one syringe on each side at the age of 12 months. One month later, the ultrasound showed a dilation of the distal ureters (diameter of the right ureter, up to 10mm; left ureter, up to 6.7mm). The child underwent surgery 8 months later (Cohen procedure) because of iterative pyelonephritis and persistent ureter dilatation. Only one previous case has been described in the literature. In our experience, this complication has occurred only twice in 452 injections (4‰). In conclusion, endoscopic treatment with hyaluronic acid/dextranomer injection is a minimally invasive procedure that improves the situation in cases of VUR. It has few complications. Other than failure, there is a low risk of secondary expansion requiring, in our opinion, ultrasound verification over the long term.