Article

Some patients receiving botulinum toxin type A therapy develop
immunological resistance due to the production of neutralizing antibodies against
the neurotoxin, thus partially or completely reducing the therapeutic effect.
We report here neurophysiological and clinical findings for a
58-year-old man treated with botulinum toxin type A for spasticity after
ischaemic stroke, who became a secondary non-responder patient. Subsequent
treatment with a different preparation of botulinum toxin type A had a great
therapeutic effect on his spasticity. The muscles injected and the dosages were
the same for each treatment, but evaluation with the Modified Ashworth Scale
after treatment with the second preparation showed a reduction of approximately 2
points compared with the first examination. The clinical results were also
supported by extensor digitorum brevis testing of the right muscle, which showed
a reduction in compound muscle action potential, whereas it was unchanged in the
non-injected muscle. No side-effects were reported, and after 1 year of treatment
with this formulation clinical benefits were still evident. CONCLUSION: The
neurophysiological and clinical results obtained in this patient suggest that
switching therapy from a complexing protein-containing product to a product
potentially free of complexing proteins, which has low immunogenicity, may be a
viable therapeutic option in secondary non-responder patients.

Langue : ANGLAIS