Task-specific facial dystonia following COVID-19 infection: A case report.

[RATIONALE] During the coronavirus disease of 2019 (COVID-19) pandemic, various movement disorders associated with COVID-19 infection have been reported. However, the incidence of dystonia specifically associated with COVID-19 infection has been particularly rare.

[PATIENT CONCERNS] A 43-year-old male patient presented to the movement disorders clinic with complaints of facial grimacing while chewing and experiencing spasms during nasal breathing. These symptoms appeared 2 weeks after he tested positive for COVID-19.

[DIAGNOSES] Based on normal diagnostic test results, including brain imaging and blood tests, it was concluded that task-specific facial dystonia following COVID-19 infection.

[INTERVENTIONS] Despite treatment with clonazepam, trihexyphenidyl, and carbamazepine, his condition did not improve. Subsequently, botulinum toxin injections were administered to the affected facial muscles identified through video analysis.

[OUTCOMES] Botulinum toxin injections led to a significant improvement in the patient's symptoms.

[LESSONS] Task-specific dystonia affecting the facial muscles, particularly induced by specific actions such as chewing and nasal breathing, is rare and may represent an atypical post-infectious manifestation of COVID-19.