Isolated vagus nerve palsy probably associated with herpes simplex virus infection.

Vagus nerve palsy caused by herpes simplex virus (HSV) infection is rare. Here, we present a 29-year-old man with acute onset of right side otalgia and sore throat, followed by dysphonia, dysphagia and some vesicles seen on the deep soft palate. Laryngoscopy revealed right vocal cord palsy. Neck to chest CT did not reveal local lesion. Three months later, his serum HSV IgG antibody titer was eight times elevation and a throat swab culture for virus isolation yielded HSV type I. T2-weighted images of neck MRI showed abnormally high signal intensity on the right sub-glottis region with Gadolinium enhancement that was compatible with local infection. Thereafter, one course of acyclovir; was given. Three months after finishing the acyclovir, his symptoms were almost gone and neck MRI did not show the aforementioned lesions. HSV infection should be considered as a differential diagnosis for patients with idiopathic dysphonia and dysphagia.