ALTHOUGH IT is often assumed that Lyme disease is a common cause of facial nerve palsy in endemic areas, in fact there are few data that address this issue. Furthermore, there is little information about how the condition of children who live in these areas in whom facial nerve palsy develops should be evaluated; there is also little information about how these children should be treated if they do have Lyme disease. Belman et al1recommend that serologic tests for Lyme disease and a lumbar puncture should be performed in all children with facial nerve palsy who live in endemic areas. The implication is that if a diagnosis of Lyme disease is made and test results of cerebrospinal fluid (CSF) are abnormal, such children should be treated with a course of parenterally administered antimicrobial therapy. Is such an approach justified? We do not know either the proportion of