Lyme disease (also called Lyme borreliosis) is a multisystem illness caused by the spirochete Borrelia burgdorferi. It is the most prevalent tick-vectored illness in North America and Europe. The dermatologic and neurologic signs and symptoms were first described in Europe in the early 1900s. In the United States the first report of a case of erythema migrans (EM), the characteristic skin manifestation, occurred in Wisconsin in 1969. The broader clinical spectrum of the disease was recognized in the mid-1970s with the occurrence of a cluster of arthritis cases in the lower Connecticut River Valley town of Lyme, for which the disease was named.

Largely because this complex disease is newly recognized and incompletely studied, knowledge of it has had to be continually updated. This has created confusion and controversy. For example, it was first thought that the etiologic agent was a virus until the causative spirochete was discovered (Burgdorfer et al, 1982). Initially, the disease was termed Lyme arthritis, and “no arthritis, no Lyme” was a common dictum. The illness is now known to be more complex, and the name has been changed to Lyme disease. Arthritis is a common, but not necessary, component.

Patients who fulfill the diagnostic criteria are more numerous and geographically widespread than previously thought. Both seronegativity (Dattwyler et al, 1988; Liegner, 1993) and persistent infection after standard antibiotic therapy have been proven (Preac-Mursic et al, 1989). There has been a trend toward longer and more aggressive antibiotic therapy (Rakel, 1997). The Ixodes dammini deer tick as a separate tick species no longer exists and has been reclassified back to the more widespread Ixodes scapularis (Oliver et al, 1993). Increasing heterogeneity of the spirochetes is now known (Mathiesen et al, 1997), as is the ability of culture media to select or favor certain strains or genotypes (Norris et al, 1997). Failure to obtain a positive culture does not prove absence of infection.

The entire concept of Lyme disease in the lower Midwest and South challenges the prevailing paradigm (Oliver, 1996). Clinically the patients are similar (Masters et al., 1994; Masters & Donnell, 1995), but what to call the condition when the etiologic agent is found to be a related spirochete, but not B. burgdorferi, has not be determined. Regardless of the name, these Southern and Midwestern patients with clinical Lyme disease need to be treated (Masters & Donnell, 1996).

The primary care provider’s role is paramount in the diagnosis and treatment of Lyme disease, as early diagnosis and treatment translate into better outcomes. The best opportunity for an accurate early diagnosis is the characteristic EM or bull’s-eye rash stage (Fig. 16-1; Masters, 1995). The rash, however, may be transient, while the infection can persist and disseminate. Patients may get the rash, make an appointment that is 2 weeks away, and then have the rash fade. Believing they are getting well, patients might cancel the appointment, and an early therapeutic and diagnostic opportunity is missed. The rash is often relatively asymptomatic, and because tick bites on the hands and face are unusual, rarely are they found on a cosmetically sensitive body area. This adds to the lack of awareness by the patient of the seriousness of the condition. If patients with rashes or febrile illnesses after tick bites are not given prompt appointments, preferably within 2 or 3 days, the chances of dissemination, canceled appointments, and missed pathology are all increased.

Researchers and providers are still on the front end of the learning curve for this complicated disease, especially when it is in the late or disseminated phase. Providers can best serve their patients with education, early diagnosis, and effective treatment.