Risk factors for urinary tract infection after dextranomer/hyaluronic acid endoscopic injection

Endoscopic injection of dextranomer/hyaluronic acid is an option for primary vesicoureteral reflux. Few groups have assessed the rate of urinary tract infection after dextranomer/hyaluronic acid injection. We reviewed our experience with dextranomer/hyaluronic acid injection, and determined the incidence of and risk factors for postoperative urinary tract infection.

A retrospective cohort study was performed of all children with primary vesicoureteral reflux treated with dextranomer/hyaluronic acid from 2002 to 2007 at a single institution. Patient demographics and clinical outcomes were abstracted from the medical record. Risk factors for postoperative urinary tract infection, including female gender, preoperative vesicoureteral reflux grade, recurrent urinary tract infection, bladder dysfunction, nephropathy and persistent vesicoureteral reflux after surgery, were analyzed in a multivariate logistic regression model.

We treated 311 children, of whom 87% were female and 13% were male (464 renal units), during the study period. Mode of presentation was urinary tract infection in 85% of cases. Mean followup was 2.6 years. Postoperatively urinary tract infection developed in 40 patients (13%) and febrile urinary tract infection developed in 11 (3.5%). Of patients with urinary tract infection 26 had initially negative postoperative voiding cystourethrogram, of whom 16 underwent repeat voiding cystourethrogram and 9 showed recurrent vesicoureteral reflux. Five of these 9 patients had clinical pyelonephritis. Of assessed risk factors only preoperative recurrent urinary tract infection (OR 2.2, p = 0.03) and bladder dysfunction (OR 3.3, p = 0.001) were independent predictors of post-injection urinary tract infection.

In our series urinary tract infection after dextranomer/hyaluronic acid injection was rare. Patients with recurrent urinary tract infections and bladder dysfunction preoperatively are at increased risk for urinary tract infection after treatment. Patients with febrile urinary tract infection after dextranomer/hyaluronic acid injection are at high risk for recurrent vesicoureteral reflux.