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Updated: Jul 8, 2026

A High-throughput-compatible FRET-based Platform for Identification and Characterization of Botulinum Neurotoxin Light Chain Modulators
Published on: December 27, 2013
Neutralizing antibodies in dystonic patients who still respond well to botulinum toxin type A
1Department of Neurology, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria. gottfried.kranz@meduniwien.ac.at
Background:
Complete secondary therapy failure due to antibodies against botulinum toxin A (BoNT/A-ABs) may raise extensive treatment difficulties. We tested whether neutralizing BoNT/A-ABs can be detected in dystonic patients with good clinical responses to botulinum toxin A (BoNT/A) treatment.
Methods:
We used the ninhydrin sweat test (NST) and the mouse diaphragm test (MDT) in 28 subjects. Of 119 dystonic patients who responded well to BoNT/A, we randomly selected 14 and compared the results of the NST and MDT with 14 healthy controls.
Results:
Higher BoNT/A-AB titers correlated significantly with smaller anhidrotic areas. We found seven patients with borderline antibody (AB) values (MDT 0.4 to 0.8 mU/mL) with significantly smaller anhidrotic areas (NST) compared with healthy controls and AB-negative patients. Risk factors for smaller anhidrotic areas were short injection intervals but not prolonged exposure to BoNT/A or high injection doses.
Conclusions:
These data demonstrate that >40% of dystonic patients who respond well to botulinum toxin A (BoNT/A) show partial nonresponsiveness on the ninhydrin sweat test and have low titers of neutralizing BoNT/A antibodies.
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