Lyme Disease in Canada

A 56-year-old woman presented to the emergency department with a new well-defined erythematous patch on her right clavicular region (Figure 1), myalgia and chills. The patient was prescribed cephalexin for cellulitis by the emergency department physician; however, the patient returned 15 days later with palpitations and light-headedness. She remembered a possible tick bite while running outdoors in a region endemic for Lyme disease.