Cerebellar mutism caused by primary varicella infection in an immunocompetent child

Varicella (chickenpox) is a common childhood infection caused by the varicella-zoster virus, which is often self-limiting and usually benign. Although uncommon, neurologic complications of varicella have been documented that include postinfectious cerebellar ataxia, meningoencephalitis, Reye syndrome, myelitis, optic neuritis, stroke, Guillain-Barré syndrome, seventh cranial nerve palsy, and Ramsay-Hunt syndrome. In this case study, the authors describe a 7-year-old girl who presented with varicella skin rash with unsteady gait and anarthria on day 2, and her condition was attributed to cerebellar mutism. To date, this complication has never been reported in a child with primary varicella infection. Therefore, this case study documents a rare but serious complication of childhood chickenpox.