A two-centre study of risk factors involved in renal deterioration in neurogenic bladder in children after myelomeningocele

Introduction
Myelomeningocele (MMC) is the first cause of neurogenic bladder in children. Adequate nephrourological management is crucial to prevent renal damage and bladder dysfunction. In the last decade, the prognosis of MMC children has dramatically improved, but can we do better? We wanted to detect risk factors involved in renal deterioration in MMC patients.

Material and methods
This retrospective analysis was based on 178 children with MMC (99 girls and 79 boys) from two Polish hospitals, in Bialystok and Cracow. The children’s medical records were analysed to determine sex, age, and kidney and urinary tract ultrasound, voiding cystourethrogram, and urodynamic findings. The number of clean intermittent catheterisations performed per day, cystatin C, serum creatinine, urea, and glomerular filtration rate (GFR) Schwartz were also recorded. The Hoffer scale was used to assess MMC children’s motor function.

Results
Of the 111 from Bialystok and 67 children from Cracow, with a median age of nine years, 45 (25%) had vesicoureteral reflux. The most common urodynamic finding was overactive bladder with a prevalence of 59%. There were statistically significant differences between girls and boys, including the presence of reflux, increased echogenicity of the kidneys’ parenchyma in ultrasound examination and cystometric capacity in urodynamic study. There were statistically significant differences between the Hoffer scale groups, including GFR Schwartz. The number of performed urodynamics correlated with GFR Schwartz, serum concentrations of cystatin C, and creatinine.

Conclusions
Potential risk factors of renal deterioration in children with MMC are abnormalities in ultrasound, the presence of high-grade vesicoureteral reflux in cystogram, increased bladder pressure on urodynamics, hyperfiltration, and increased levels of cystatin C. Urodynamic evaluation may play a role in the management of children with MMC by identifying those with increased bladder pressures. Frequent urodynamic assessment may contribute to prevention of renal function in children with MMC.