Reversible palsy of the hypoglossal nerve complicating infectious mononucleosis in a young child.

We report a 7-year-old boy with serologic evidence of active Epstein-Barr virus (EBV) infection who developed transient unilateral hypoglossal nerve palsy, with complete recovery within 21 days. This is, to our knowledge, the youngest reported patient with isolated hypoglossal nerve palsy in the context of EBV infection. Acute EBV infection should be considered early in the evaluation of children with twelfth nerve palsy in order to avoid extensive ancillary testing.