Methods

A retrospective observational study was carried out, reviewing records of patients diagnosed with vesicoureteral reflux, and submitted to endoscopic injection surgery between December 2011 and February 2015, by the Pediatric Urology Department of the Hospital Nacional de Niños (National Children’s Hospital) “Dr. Carlos Sáenz Herrera “.

Patients with a diagnosis of primary or secondary VUR were included, in whom it was possible to correct the secondary cause, although they persisted with VUR. Patients with persistent voiding dysfunction and those without VCUG after anti-VUR endoscopic injection were excluded.

In each case, the patient’s epidemiology (gender, age of diagnosis, patient’s clinical condition, surgical indication, associated pathologies) and pre-surgical studies (urinary tract ultrasound, VCUG, DMSA), surgical indication, the substance used for endoscopic injection, and post-surgical studies (ultrasound of the urinary tract, VCUG and VCUG by radionuclides).

Figure 1: Original endoscopic injection technique. The arrow shows the injection site related to the ureteral orifice (middle image) 

Figure 2: A) Appearance of a refluxing ureter B) After endoscopic injection, a bulge image is seen (mount shape). 

Substances used in this study for endoscopic anti-reflux injection are: Macroplastique and Vantris.

Data was tabulated and graphs were made in the Microsoft Office Excel 2013 software.

Results

A total of 33 cases evaluated at the Pediatric Urology Service of the Hospital Nacional de Niños with a diagnosis of VUR, according to clinical and test results, were submitted to endoscopic anti-VUR injection between December 2011 and February 2015.

Out of the analyzed population, 66.6% were girls and 33.3% were boys. There was no mean age of VUR diagnosis. In patients with VUR, the degree of reflux was classified on each affected side, with a total of 42.4% of patients with bilateral VUR (14 cases), 36.36% (12 Cases) with left VUR, and 21.21% (7 cases) with a right side affected; accounting for a total of 47 ureteral units evaluated.

The most frequently diagnosed reflux degree was grade II, in 44.7%, followed by grade III in 38.3% of cases. The most frequent reflux type was of primary origin, in 82% of patients.

The most frequent symptoms were: symptomatic urinary tract infection (82%), enuresis (3%), macroscopic hematuria (3%), impaired renal function (6%) and only 6% of the patients were asymptomatic (incidental diagnosis due to ureteral dilatation).

VUR was associated with detrusor sphincter dyssynergia in 12% of cases, duplicated collecting system in 9%, polycystic kidney in 6%, paraureteral diverticulum, renal agenesis and hypospadias in 3% of cases.

The preoperative studies performed in all cases were: urinary tract ultrasound, VCUG and DMSA. The most frequent alteration was the loss of the cortical-medullary ratio in 24% of the cases, followed by the ureteropyelocalicial dilatation of the affected system in 21%, multicystic kidney in 6%, renal ectopia, lithiasis and renal agenesia in only 3% of the cases. Preoperative DMSA showed that 57.6% of the patients had renal scars.

The most frequent surgical indication was recurring urinary tract infection (39.4%); followed by persistent VUR (24.2%).

Vantris was used in 63.6% of patients and Macroplastique in 27.4%. Subureteral STING technique was the most used, in 93.9%, and only 2 cases (6.1%), performed the intraureteral technique.

Most patients presented resolved their vesicoureteral reflux after surgery (88%); less patients persisted with a lower degree of reflux than at the time of diagnosis (12%); all were again submitted endoscopic anti-reflux injection, and only one patient persisted with VUR, however it was a low grade VUR with no associated symptoms, so it is being managed conservatively.

One patient had a surgical complication, with a false urethral passage, which was managed conservatively, with excellent evolution.

Discussion

In the study population, VUR was more frequent in girls, there were patients from all provinces of the country, and the most frequent degree of VUR in patients undergoing endoscopic anti-reflux injection was grade II, followed by grade III. The sample has an important heterogeneity regarding age, ranging from 6 months to 8 years old at the time of diagnosis, and an average of 4 years old.

The average time between diagnosis and surgery was 2 and a half years, which is short considering that it includes an observation period before surgical management is indicated. As for epidemiology, data resembles that found in the literature: girls account for most diagnosis and the most common presenting symptom is urinary tract infection.

Changes in DMSA were found in 57.57%, which is associated, according to the literature, with late diagnosis of vesicoureteral reflux, and inadequate management of urinary tract infections. Preoperative studies were those used in the literature: urinary tract ultrasound, VCUG and DMSA. The most frequent surgical indication is persistent urinary tract infection, and the persistence of reflux beyond 5 years old, which is the time when anatomic growth and ureterovesical junction remodeling occurs. These data agree with those described in the literature.

The majority of patients had a diagnosis of grade II and III VUR, and reported a higher rate of resolution by endoscopic anti-reflux injection; only four cases had persistent vesicoureteral reflux following anti-reflux injection, but with a lesser degree than at baseline; three cases had grade III VUR and one had grade IV; all four cases were re-injected with endoscopic anti-reflux therapy, and three resolved their VUR, while only one persisted with grade I asymptomatic VUR, so it is being given a conservative management. There are no reports of patients with grade V VUR treated with endoscopic anti-reflux injection.

Only one patient presented a complication related to the surgical procedure, and was a false urethral passage, which was managed conservatively, without major problems. According to the literature, there is a low incidence of complications with endoscopic anti-reflux injection, with injected ureterovesical junction stenosis being the most common.

The success rate of endoscopic injection in the analyzed patients was 88%. Further prospective studies are required to assess the long-term outcome of these patients, since even in the literature the latency of the injected material for this surgery has not been defined.

The correction of vesicoureteral reflux by endoscopic injection with Macroplastique and Vantris is safe, effective and minimally invasive. Early correction of VUR protects children with and without renal scars, and decreases the prolonged use of antibiotic prophylaxis. Endoscopic subureteral injection with Vantris and Macroplastique is an effective method for short-term RVU correction; the success rate is not influenced by the degree of reflux and the configuration of the ureteral orifice. Long-term results are needed from patients with VUR treated with endoscopic anti-reflux injection to assess the rate of VUR recurrence.

Authors affiliations:

¹ Urology Department, Hospital Nacional de Niños.

² Urology Department, Hospital San Juan de Dios, Caja Costarricense de Seguro Social. Universidad de Costa Rica.

Abbreviations: VUR, Vesicoureteral Reflux; VCUG, voiding cystourethrogram; US, ultrasound; DMSA, Dimercaptosuccinic Acid Gammagraphy.

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