Lymedisease is a tick-borne illness caused by the spirochete B burgdorferi. Lymedisease can be divided into early disease (stage 1, EM), disseminated infection (stage 2), and late disease (stage 3, persistent infection). The first stage involves the skin, followed by stages 2 and 3, which often affect the skin, joints, CNS, and heart. However, any of the stages may fail to appear or may overlap with one another
|Localized erythema chronicum migrans||Early infection|
|Disseminated infection||Within days or years|
|Persistent infection||Months to years|
The diagnosis of Lymedisease is made on clinical findings, epidemiologic features, and an elevated antibody response to B burgdorferi. The available laboratory tests (with the exception of a positive culture from an EM lesion) can be unreliable. Serologic testing only should be undertaken when clinical and epidemiologic features suggest Lymediseaseas the diagnosis.
Most patients with B burgdorferi are found to have detectable antibodies when tested with enzyme-linked immunosorbent assay (60-70% within 2-4 weeks of infection and 90% by the disseminated and persistent stages). However, serologic tests lack standardization, their accuracy is often unsubstantiated, and false-positive results are common. IgM antibody appears 2-4 weeks after the EM lesion, peaks at 6-8 weeks, and declines after 4-6 months. IgG antibody appears 6-8 weeks after the EM lesion, peaks at 4-6 months, and remains at low levels despite antibiotic therapy. A fourfold rise in antibody titer would be suggestive of recent infection. Western blot analysis is used to confirm results obtained by enzyme-linked immunosorbent assay.
Lyme disease is a bacterial disease caused by Borrelia burgdorferi. The bacterium is transmitted to humans via a tick bite. Within 1 to 2 weeks after being infected, a “bull’s-eye” rash can develop at the tick bite site accompanied by fever, headache, and muscle or joint pain. Some people may have Lymedisease and not have any early symptoms. However, others can have a fever and other “flu-like” symptoms without a rash.
Lyme disease may be hard to diagnose because its symptoms are like those of many other illnesses. Your doctor will take a careful medical history and do a physical examination to help diagnose early Lyme disease. You may be asked whether you have recently visited an area where you may have been exposed to ticks. The doctor will ask about your symptoms and look for physical signs that may indicate Lyme disease. The clearest physical sign is an expanding, circular red rash (called erythema migrans). See a picture of a Lyme disease rash.
The often vague, flu-like symptoms of Lyme disease can easily be misdiagnosed as another illness(such as chronic fatigue syndrome).