[Evaluation of the lower urinary tract function in pediatric patients with primary vesicoureteral reflux]

To present a methodology of perioperative evaluation of lower urinary tract function in patients with primary VUR. To describe the most frequent urodynamic patterns in patients with primary VUR and their treatment. To show the results of a lower urinary tract evaluation in a prospective study in a pediatric population of 63 patients, with persistent primary VUR, with the aim to help to a better understanding of the natural history of VUR.

The study includes a pediatric population of 63 patients with primary grade II-V VUR, 28 girls and 35 boys, with ages between six months and 15 years (mean age 5.9 yr.). In the study protocol for the systematic study of primary vesicoureteral reflux we perform a non invasive screening for lower urinary tract dysfunction, which select patients that will benefit from a complete cystomanometry.

age, gender, VUR side and grade, and renal function, in relation with the lower urinary tract function at the time of recruitment. The results of urodynamics have been evaluated in relation to urinary symptoms and history of lower urinary tract infection.

Differential characteristics of the study population: high mean age (overall 5.9 yr.; 7.7 in girls), high percentage of high grade VUR (59%), renal damage (52%) and lower urinary tract dysfunction (86%) without significant differences between boys and girls. Statistically significant associations between: VUR grade and renal damage; presence of lower urinary tract dysfunction and bilateral VUR; female gender and lower urinary tract dysfunction; and normal lower urinary tract function and absence of renal damage. The voiding dysfunction pattern was predominant in females and bladder hyperactivity in males. Urinary symptoms did not differ between the various patterns of urodynamic abnormalities. The incidence of UTI shows significant differences between the various urodynamic patterns, being more frequent in girls with type 4 urodynamic pattern (dysfunctional voiding).

The performance of a non invasive screening of lower urinary tract function by medical history, urine analysis, ultrasound and post void residual ultrasound evaluation enabled the selection of patients who would benefit from a complete urodynamic study. If there are symptoms or signs of lower urinary tract dysfunction it is recommended to perform a complete urodynamic study. Pediatric cystomanometry provides precise data about bladder filling and voiding phases, facilitating the specific treatment of the lower urinary tract dysfunction. The urodynamic study has a special significance in the prognosis of the urological malformation associated in children with VUR. With this systematic study of the lower urinary tract function early diagnosis and treatment of patients in risk may be achieved, as well as adequate selection of patients that will benefit from pharmacotherapy and/or urotherapy, with the aim to prevent renal damage progression and to potentiate definitive cure of VUR.