Lyme disease

Lyme disease

A multisystemic disorder, Lyme disease is caused by the spirochete Borrelia burgdorferi, which is carried by the minute tick Ixodes dammini or another tick in the Ixodidae family. It typically begins in summer, with the classic skin lesion called erythema chronicum migrans (ECM). Weeks or months later, cardiac or neurologic abnormalities sometimes develop, possibly followed by arthritis.

Lyme disease occurs primarily in areas of the United States inhabited by the deer tick, such as:

  • in the northeast, from Massachusetts to Maryland

  • in the midwest, in Wisconsin and Minnesota

  • in the west, in California and Oregon.

Although Lyme disease is endemic to these areas, cases have been reported in 43 states and 20 other countries, including Germany, Switzerland, France, and Australia.


Lyme disease occurs when a tick injects spirochete-laden saliva into the bloodstream
or deposits fecal matter on the skin. After incubating for 3 to 32 days, the spirochetes migrate out to the skin, causing ECM. Then they disseminate to other skin sites or organs by the bloodstream or lymph system.

The spirochetes’ life cycle isn’t completely clear: They may survive for years in the joints or they may trigger an inflammatory response in the host and then die.

Jun 16, 2016 | Posted by in GENERAL & FAMILY MEDICINE | Comments Off on Lyme disease

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