Erythema Migrans Can Vary, Making Diagnosis Difficult
Symptoms and sources of early sign of Lyme disease vary widely
WEDNESDAY, June 20 (HealthDay News) -- Erythema migrans, one of the most common early signs of Lyme disease, can be a tricky diagnosis as patients often don't recall a tick bite and can present with multiple lesions or rashes without central clearing, researchers report in the June 20 issue of the Journal of the American Medical Association.
Carrie D. Tibbles, M.D., and Jonathan A. Edlow, M.D., of Beth Israel Deaconess Medical Center in Boston, report on their search of articles on erythema migrans published since 1966, including 8,493 patients from 32 European studies, 20 U.S. studies, and one from both regions.
Overall, few patients recalled being bitten by a tick. While a solitary bite was the most common presentation (81 percent U.S.; 88 percent Europe), some patients had multiple lesions. The extent of central clearing varied. Asian and European cases of the disease tended to have larger lesions than in the United States, and symptoms were more chronic and less systemic. In non-endemic southern states of the United States, patients were more likely to have a shorter incubation period, central clearing and a history of tick bites.
The authors detailed 12 diagnostic mimics of erythema migrans including contact dermatitis, spider bites and tinea. "There is no single element in the history or physical examination that is highly sensitive by itself for the diagnosis of erythema migrans," the authors conclude.