Erythema Chronicum Migrans of Lyme Disease

Abstract

• Erythema chronicum migrans (ECM) is the distinctive cutaneous lesion of the multisystem tick-borne spirochetosis, Lyme disease. Its clinical and histologic pictures are variable. Of the 51 patients with ECM of Lyme disease, 38 patients (75%) had single lesions, 13 patients (25%) had multiple lesions, and 32 patients (62%) had extracutaneous signs and symptoms. Only 15 patients (29%) had symptoms referable to ECM. Extracutaneous signs and symptoms were absent in 12 (80%) of the 15 patients. These patients had uneventful recoveries following treatment with systemic antibiotics. Thirty-four skin biopsy specimens were obtained from the ECM lesions of 30 patients. With Warthin-Starry silver stain, the Ixodes dammini spirochete was found in 14 specimens (41%) taken from 12 (40%) of the 30 patients. Two of the Ixodes dammini spirochete-positive specimens were obtained from secondary ECM lesions. Careful clinical and histologic examination of skin lesions suggestive of ECM of Lyme disease will expedite its early diagnosis and treatment. (Arch Dermatol 1984;120:1017-1021)