A rare case of laryngeal dystonia associated with neurosyphilis: Response to botulinum toxin injection

Educational Objective: At the conclusion of this presentation, the participants should be able to describe the clinical characteristics of laryngeal dystonia in an adult with neurosyphilis and identify botulinum toxin injection as an effective treatment option. Objective: To present a case report of laryngeal dystonia associated with neurosyphilis and the therapeutic outcome of botulinum toxin injection. Study design: Case report Methods: A 43 year-old male with neurosyphilis was evaluated for persistent strained and stuttering voice despite systemic penicillin therapy. MRI of brain revealed lesions in the basal ganglia. Initial videostroboscopy showed aperiodic mucosal waves, hyperfunction of the false vocal cords, and anterior-posterior compression consistent with laryngeal dystonia. Results: After two months of speech therapy with limited improvement, the patient received 2.5 units of botulinum toxin injection to each thyroarytenoid muscle. Post-injection videostroboscopy showed marked improvement of voice quality with bilateral periodic mucosal waves and resolution of false vocal cord hyperfunction. Conclusions: This is, to our knowledge, the first case report of laryngeal dystonia associated with neurosyphilis. Botulinum toxin injection provided significant voice improvement in this setting.