A complete atrioventricular block was seen in a nine year old girl in
whom an infection with Borrelia burgdorferi was confirmed by serologic
al testing. There were no other symptoms or cutaneous manifestations o
f the disease. Though a rash on the right ear was later recalled by he
r parents. The patient was treated with high dose penicillin and orcip
renaline was given intermittently. The complete heart block disappeare
d within four days.