Repeated intradetrusor botulinum toxin type A in children with neurogenic bladder due to myelomeningocele

Purpose: We evaluated the effect of repeated intradetrusor injections of BTA in pediatric myelomeningocele not responding to medical management. Materials and Methods: After baseline history, physical examination and urodynamic assessment BTA was injected (5 IU/kg body weight, maximum 300 IU) at 10 to 30 sites. Clinical and urodynamic assessment was performed at 3 months after each injection. Re-treatment was offered when clinical symptoms returned. Results: A total of 20 patients (average age 13 years) received BTA injections. Of the patients 13 became continent. MBC increased from 215.6 +/- 58.8 cc to 338.3 +/- 98.4 cc (p < 0.01), MDP decreased from 43 +/- 13.7 cm H2O to 21.6 +/- 10.5 cm. H2O (p < 0.01) and compliance increased from 5.2 +/- 2.6 ml/cm H2O to 13 +/- 6.9 ml/cm. H2O (p < 0.01). At an average of 8.1 months after the first injection all 13 patients received a second injection, which led to similar improvement, ie MBC increased from 200.5 +/- 41.6 cc to 404.2 +/- 57.8 cc (p < 0.001), MDP decreased from 48.18 +/- 6.1 cm H2O to 27.8 +/- 3.7 cm H2O (p < 0.01) and compliance increased from 6.0 +/- 3.1 ml/cm. H2O to 15.1 +/- 5.2 ml/cm H2O (p < 0.01). Among the responders 3 received 3 injections and 1 received 4 injections, all of whom exhibited improvement similar to that seen initially. Among our initial cohort of 20 patients 7 failed to improve initially and 6 failed to improve after a second injection. Conclusions: BTA seems to be a simple and safe way to postpone or avoid invasive procedures in two thirds of children with myelomeningocele not responding to usual medical treatment.