Impact of intradetrusor botulinum toxin A injections on serum and urinary concentrations of nerve growth factor and brain-derived neurotrophic factor in patients with multiple sclerosis and neurogenic detrusor overactivity.

AIMS: To evaluate the practical relevance of changes in serum and urinary neurotrophins levels in patients with multiple sclerosis (MS) and neurogenic lower urinary tract dysfunction (NLUTD) after intradetrusor injections of botulinum toxin A (BoNTA). METHODS: The study included 36 patients with MS and NLUTD and 20 controls. The patients with NLUTD received intradetrusor injection of BoNTA (200 U). The nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) levels were measured in serum and urine at baseline and then at 1, 3, and 6 months by enzyme-linked immunosorbent assay. Urinary NGF and BDNF were normalized to creatinine (NGF/Cr, BDNF/Cr). Patients' assessment included urodynamic examination and Neurogenic Bladder Symptom Score (NBSS). RESULTS: After BoNTA injections, no significant changes were observed in the serum NGF and BDNF or the urinary BDNF/Cr. The urinary NGF/Cr was significantly higher in MS patients (1.23 ± 0.34) at baseline compared with controls (0.084 ± 0.02; p = .021). The urinary NGF/Cr decreased to 0.51 ± 0.12 (p = .001) and 0.53 ± 0.32 (p = .005) at 1 and 3 months, increasing to 1.12 ± 0.49 (p = .003) at 6 months. The urinary NGF/Cr level at baseline demonstrated a low diagnostic accuracy in predicting a better response to the BoNTA treatment (area under the curve = 0.661; p = .047) and no correlation with the urodynamic parameters. CONCLUSIONS: The urinary NGF/Cr at baseline or its reduction at the first month following treatment does not serve as a predictor for the response to the BoNTA injections or for urodynamic changes.