Lyme disease is a complex, multisystem illness that is caused by the microorganism Borrelia burgdorferi. Borrelia burgdorferi is a tick-borne spirochete, which is transmitted by Ixode ticks. The ticks act as a reservoir for the bacteria, which can then be transmitted through their bites. Typically the tick must stay attached to a human source for 24-48 hours in order to transmit the bacteria. The disease was first recognized in 1975 in Lyme, Connecticut, for which it is named.
Lyme disease can be broken down into three stages. The first stage begins after a period of 3-30 days, and is characterized by a classic “bulls-eye” lesion, also known as erythema migrans. This is pictured above, and is seen at the site of infection. It may be accompanied by fever, malaise, headache, and joint and/or muscle pain.
The second stage occurs 1-6 months following the initial stage. Arthritis is the main presenting symptom, with associated muscle pain and swollen lymph nodes. A certain percentage of patients will neurological symptoms, including meningitis or Bell’s Palsy. Some will present with carditis as well.
The third stage may occur months to years after exposure. There is chronic neurological involvement, most commonly a subtle form of encephalopathy that affects mood, memory, and sleep. Arthritis and muscle pain may be a chronic symptom by this stage.
Treatment of Lyme disease depends on the stage of the disease at presentation as well as the symptoms. Antibiotics are used in the early stages to fight the spirochete infection. Doxycycline, tetracycline, and amoxicillin have all been used. Neurological abnormalities may be treated with cephalosporins or penicillin. As for the arthritis associated with Lyme disease, the symptoms are generally treated much like any other arthritis. NSAIDs with or without intra-articular steroid injections may be of benefit.
Of course, the disease should be treated before it progresses from the first stage. With the presence of arthritis plus a history of possible exposure to ticks and a bulls-eye rash, antibiotics should be started. Laboratory testing is typically limited to a blood draw to look for IgM antibodies. However, this will often take 3-6 weeks to show up. Therefore, antibiotics may need to be started before an absolute diagnosis can be made. An ELISA test or a Western blot can be performed to confirm the diagnosis after empiric therapy is started.
Incidence of Lyme disease is most common in wooded areas. In particular, the disease persists in the Northeastern United States, as well as parts of Minnesota, Wisconsin, and Northern Michigan.
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