Recognizing And Treating Lyme Disease In The Lower Extremity

In January this year, when the weather was unusually warm, I decided to go for a hike through Pennsylvania with my husband and dogs. I couldn’t believe my eyes when I spotted a tick in the brush. Sure enough, we found several more on our dogs that evening. With mild winter temperatures continuing well into the months of January and February, expect an early return of Lyme disease.

Lyme disease is the most common tickborne disease in the United States and Europe. The average incidence in the United States in 2015 was 8.9 confirmed cases per 100,000 people.¹ Lyme disease can affect all ages and genders although there is an increased risk of infection with longer times spent outdoors.² It most commonly occurs in forested regions. In the United States, Connecticut, Maine, Pennsylvania, Rhode Island and Vermont are just a few of the high incidence states, all reporting over 50 confirmed cases per 100,000 people in 2015.¹

Lyme disease is a spirochetal infection caused by the Gram-negative bacteria Borrelia burgdorferi sensu lato. B. burgdorferi is the primary cause of Lyme disease in the United States. In addition to B. burgdorferi, Borrelia afzelii and Borrelia garinii are identified causes of Lyme disease in Europe and Asia.^2,3 

Lyme disease is transmitted via the bite of an infected blacklegged tick Ixodes ricinus or Ixodes scapularis.⁴ The tick acts as a vector and must be attached for 24 to 48 hours for transmutation of the spirochete to occur.⁵

What Are The Stages And Clinical Manifestations Of Lyme Disease?

We can divide clinical manifestations of Lyme disease into three phases: early localized disease, early disseminated disease and late Lyme disease. It is important to recognize and understand the phases of Lyme disease as this dictates antibiotic therapy and treatment. Patients may present at any point during the course of the infection and each phase has overlapping symptoms. Furthermore, not everyone may experience the early symptoms of the disease.

Early localized disease begins three to 30 days after a tick bite. The characteristic, painless erythema migrans skin rash is evident and often the first sign of the disease. Patients may also experience mild flu-like symptoms, such as fatigues, headache, myalgias, arthralgia, fever, lymphadenopathy or loss of appetite.

Early disseminated disease begins within one month following the appearance of the erythema migrans skin rash. At this point, the spirochete has entered the blood or lymphatic system. Symptoms at this sage include transient monoarticular or oligoarticular arthritis, radiculopathy, lymphocytic meningitis, cranial neuropathies, myopericarditis, or atrioventricular nodal block. Furthermore, flu-like symptoms that present with early localized disease may still be evident.

Late disseminated Lyme disease may occur months to years following a tick bite. In this stage, systemic and flu-like symptoms are no longer present. Patients may experience intermittent or chronic arthritis, peripheral neuropathy or encephalomyelitis.^5,6

Pertinent Insights On Diagnosing Lyme Disease

Serologic testing is indicated in the presence of symptoms consistent with the early disseminated or late disseminated disease. Perform serologic testing with an enzyme-linked immunosorbent assay (ELISA), which can identify IgM or IgG antibodies to B. burgdorferi. If the ELISA demonstrates positive or borderline positive results, one can utilize a Western blot test. If the Western blot test is negative, it invalidates a positive ELISA result.^2,5-6

Although these diagnostic modalities are effective, if a patient presents with a known tick bite and an erythema migrans rash in an area where Lyme disease is endemic, authors do not recommend serologic testing.⁴ Furthermore, it is not the standard of care to perform an ELISA or Western blot test on all individuals bitten by a tick. Only about one-fourth of individuals with Lyme disease will remember being bitten by a tick but the inability to recall a tick bite does not dismiss the diagnosis of Lyme disease.⁵

What Are The Treatment Option For Lyme Disease?

Drugs of choice for Lyme disease include penicillin, cephalosporins and tetracyclines. For early localized disease, oral doxycycline, cefuroxime or amoxicillin for 14 to 21 days can effectively eradicate the disease. With early disseminated disease, treatment extends to 28 days. In the presence of late disseminated disease with organ involvement, intravenous antibiotics, such as ceftriaxone, may be required for two to four weeks until symptoms resolve.^2,5-6

References

1. Centers for Disease Control and Prevention. Lyme disease data tables. Available at https://www.cdc.gov/lyme/stats/tables.html#modalIdString_CDCTable_1 .
2. Beard BC. Epidemiology of Lyme disease. UpToDate. Available at https://www.uptodate.com/contents/epidemiology-of-lyme-disease?source=see_link . Published Aug. 18, 2016.
3. Vázquez-López ME, Díez-Morrondo C, Sánchez-Andrade A, et al. Articular manifestations in patients with Lyme disease. Reumatol Clín. 2016; 12(6):327-330.
4. Lascher S, Goldmann DR. Efficacy of antibiotic prophylaxis for the prevention of Lyme disease after tick bite. Am J Med. 2016; 129(9):935-937.
5. Gerstenblith TA, Stern TA. Lyme disease: A review of its epidemiology, evaluation, and treatment. Psychosomatics. 2014; 55(5):421-429.
6. Hu L. Clinical manifestations of Lyme disease in adults. UpToDate. Available at https://www.uptodate.com/contents/clinical-manifestations-of-lyme-disease-in-adults?source=search_result&search=lyme%20disease&selectedTitle=1~150. Published Aug. 17, 2016.
7. Oda R, Kutsuna S, Sekikawa Y, et al. The first case of imported Borrelia miyamotoi disease concurrent with Lyme disease. J Infect Chemother. 2017; epub Feb. 2.
8. Moore KS. Lyme disease: diagnosis, treatment guidelines, and controversy. J Nurse Pract. 2015; 11(1):64-69.