Lyme disease affects an estimated 300,000 people per year in the United States.
Lyme disease is divided into
Early disease (erythema migrans [EM])
Early disseminated disease (multiple EM lesions, Bell palsy, meningitis, carditis)
Late disease (arthritis)
EM should be diagnosed clinically, as laboratory test results may be negative.
Serology should be considered for the diagnosis of disseminated or late disease only in children with compatible clinical symptoms.
Lyme disease has an excellent prognosis if treated with appropriate antibiotics.