Successful treatment of post COVID-19 neurogenic dysphagia with botulinum toxin

Introduction: Dysphagia in post COVID-19 patients could be caused by several factors, including reduced pharyngolaryngeal coordination due to SARS-CoV-2 tropism to the central and/or peripheral nervous system. To our knowledge, this is the first reported case of COVID-19-related dysphagia successfully treated with botulinum toxin type A injection. Case description: We report the case of a patient with severe oropharyngeal dysphagia due to COVID-19 confirmed by fibre endoscopy. As a result, the patient required an enteral feeding tube. After two months of traditional swallowing therapies, there was only limited improvement. An electrophysiologic evaluation of the cricopharyngeal muscle was performed and showed a normal inhibition of the cricopharyngeal muscle, followed by a hypertonic rebound. Based on this result, we decided to perform a unilateral laryngeal injection of botulinum toxin type A. After the injection, the patient’s swallowing function improved significantly, allowing him to return to oral feeding. Discussion: Newly diagnosed oropharyngeal dysphagia was found in 35.3% of hospitalised patients with COVID-19. There are several possible causes of COVID-19-associated dysphagia, including stroke, encephalitis, critical illness neuropathy, Guillain-Barré syndrome and skeletal muscle injury. In our case, since stroke was excluded by brain MRI, cranial nerve injury was a possible explanation for the difficult recovery of swallowing despite daily swallowing therapy. Conclusion: We suggest that electrophysiology is a valid tool for the diagnosis and follow-up of patients with oropharyngeal dysphagia.