Repeated Intradetrusor Botulinum Toxin Type A in Children With Neurogenic Bladder Due to Myelomeningocele

Abstract

We evaluated the effect of repeated intradetrusor injections of BTA in pediatric myelomeningocele not responding to medical management. 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. 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. 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.