Neuronal intranuclear inclusion disease presenting with dysphagia: a report of three cases

Neuronal intranuclear inclusion disease (NIID) is a rare neurodegenerative disease that is pathologically characterized by the presence of eosinophilic hyaline intranuclear inclusions in neurons, astrocytes, and specific somatic cells. Previously reported cases of NIID displayed various neurological symptoms, including dementia, muscle weakness, ataxia, etc. However, dysphagia associated with NIID have rarely been reported. Here, we report on three cases of NIID with dysphagia. Bolus mastication and transport were impaired in all three cases. Delay of the initiation of pharyngeal swallowing and silent aspiration was observed in two cases. Combined with the brain magnetic resonance imaging (MRI) findings, oropharyngeal dysphagia associated with NIID was suggested to be attributed to diffuse subcortical lesions.