Dextranomer/hyaluronic acid injections for patients with vesicoureteral reflux Does the age at injection predict the outcome?

INTRODUCTION

We aimed to assess the impact of age of the initial dextranomer/hyaluronic acid (Dx/HA) injection on the subsequent outcome, including the need for repeated injections.

METHODS

The charts of patients who underwent Dx/HA injection from 2010-2020 were retrospectively reviewed. Two groups were created according to the number of Dx/HA injections: single vs. repeated injections. Patients who presented with antenatal hydronephrosis, neurogenic bladder, and followup less than one year after the first injection were excluded. Repeated Dx/HA injections were indicated in patients with documented vesicoureteric reflux (VUR) who experienced recurrent febrile urinary tract infection (fUTI) postoperatively.

RESULTS

A total of 172 patients with 189 renal units were included; 139 (73.5%) units underwent single injections, whereas 50 (26.5%) had repeated injections. Twenty-three (48.9%) patients with repeated injections presented before the age of one year vs. 24 (51.1%) after the age of one year (p=0.02). Of the repeated group, 34 (68%) units received two injections, 14 (28%) were injected three times or more, and two (4%) had other treatment modalities. Forty-four percent of units requiring repeated injections had high-grade VUR (grades 4 and 5), compared to only 22.3% of those successfully treated with a single injection (p=0.003).

CONCLUSIONS

In our cohort, 26.5% of renal units underwent repeated Dx/HA injections. Forty-four percent of units with repeated injections had grade 4-5 VUR. Patients with VUR who were injected or presented with fUTI before the age of one year old were at higher risk of repeated injections than those who were injected or presented later.