Lyme disease is a multisystem illness with acute and chronic manifestations as a result of infection by the spirochete Borrelli port dorsi. This spirochete is borne by the deer tick Ixodes dsammini. Lyme disease was first encountered in 1975 when several children in a Connecticut town developed arthritic illnesses of unknown origin. Lyme disease is one of the most prevalent vector borne illnesses in the United States with nearly 50,000 cases reported since 1982. The Northeast portion of the US reports the highest incidences of Lyme disease followed by the Midwest and Pacific Northwest. Lyme disease has also been reported in Asia and parts of Europe.
Patients with Lyme disease initially have variable flu-like symptoms. It is often overlooked as being viral illness when in fact it is the early manifestations of this disease. The symptoms are commonly accompanied by distinctive skin lesions known as a “target lesion” (erythema migrans) A “target lesion” is found on the extremities or in areas where the patient has been bitten by a tic. Arthralgia associated with Lyme disease will present as isolated unilateral knee pain and swelling. Remember that unilateral joint arthralgia and swelling should make the provider think of other possible manifestations. However polyarticular arthralgias are uncommon with Lyme disease. There are cardiovascular manifestations that occur and less than 10% of patients and neurologic symptoms that affect less than 15% of patients. These neurologic effects typically present as cranial nerve palsy (Bell’s palsy). In patients who have developed chronic Lyme disease, often have symptoms that do not manifest themselves for several years but develop chronic or recurrent arthritic conditions. Patient’s can present with chronic fatigue, fibromyalgia-type symptoms, encephalopathy’s resulting in memory loss and difficulties with concentration.
Physical examination for patients exposed to Lyme disease should undergo a comprehensive skin assessment, evaluation for erythema migrans and joint evaluations for symptomatic complaints. Patient’s who present with Lyme disease related arthralgia would have limited range of motion, joint effusions and/or symptoms of acute or subacute recurrent synovitis. There is usually no history of trauma, joint instability or musculoskeletal weakness directly related to Lyme disease. X-ray findings may reveal some osteoarthritis joint changes but no clear-cut manifestations are associated with Lyme disease. Lyme disease is usually diagnosed through serology specifically looking for levels of Borrellia in the blood. These are typically referred to as a Lyme panel or Lyme titers. A positive Lyme titer is usually evident in later stages of the disease and is not found on acute infection. Difficulty in diagnosing Lyme disease can occur secondary to patients who have an underlying history of arthritic changes in weight bearing joints, history of cranial nerve palsy, fibromyalgia or chronic fatigue syndrome’s, cognitive abnormalities, cardiac conduction abnormalities and peripheral vascular disease or peripheral neuropathy.
Avoidance is the most common way to minimize exposure to Lyme disease. Patients should take great care when walking in wooded areas or in areas that have a history of endemic Lyme disease. Long sleeves, tucking in shirttails, wearing long pants and tucking long pants into socks are all methods to limit ticks gaining access to skin surfaces. Frequent checks of clothing and skin are important to limit tick bites. If an imbedded tick is found on the skin, it should be removed within 24-36 hours to minimize exposure to Lyme disease. The best method for removal of imbedded ticks is using fine tweezers to disengage the tick. Using heat or caustic chemicals can have an adverse effect on the patient’s skin tissues. Once a tick is removed the skin should be thoroughly cleansed and monitored for several days. Antibiotic treatment for Lyme disease is typical but often not necessary if the tick is removed within 24 hours. However patient’s concerns, expectations and sound clinical judgment should all be taken into consideration when determining if antibiotic therapy is warranted.
Those patients who have confirmed cases of Lyme disease (or exposures) are treated with antibiotics to eradicate the spirochete. Doxycycline (100 mg twice daily for 10-30 days) and Amoxicillin (500 mg 3 times daily for 10-30 days) are the common antibiotics used in treatment for adult patients. Children under the age of 8 years should be treated with Amoxicillin 20 mg per kilogram in divided doses according to their weight. Duration of treatment is between 10 and 30 days in these patients. If patient’s bitten by a tick who so not present initially with symptoms but later develop changes in mentation, develop monoarticular joint manifestations, erythema migrans, evidence of skin or joint infection they should be treated accordingly. Close follow-up of patients who have been bitten by a tick or who have acute manifestations, of Lyme disease is encouraged to ensure no further manifestations of this disease.
Lyme disease can often be overlooked in patients who present with flulike symptoms and who report little exposure to the Borrellia spirochete. It is important to determine the level of a patient’ outdoor activities and possible tick exposure during the historical review. This is especially important during warm weather months and for patients living in high exposure areas. However, providers who work in year-round warm weather climates should always be suspicious of Lyme disease exposures. If detected early and the tick is removed no treatment is necessary. However, in a patient who have concerns regarding contracting Lyme disease or who presents with the classic target lesion (erythema migrans) antibiotic therapy is recommended. In most cases patients will have resolution of there symptoms after completing antibiotic therapy and usually will not be affected long-term.
See Thomas Gocke, MS, ATC, PA-C, DFAAPA speak in 2017 at Skin, Bones, Hearts & Private Parts.