Review Question - QID 103014

This patient with a pathognomonic Bull's eye rash most likely has Lyme disease. Prognosis following appropriate antibiotic therapy is excellent and most patients are symptom free.

Lyme disease is the most common tick-borne disease in the United States, and is seen mainly in the Northeast. It is caused by Borrelia burgdorferi, a bacteria carried by the Ixodes deer tick. The most common early manifestation of Lyme disease is erythema migrans, a characteristic target-shaped skin lesion at the site of the tick bite, while later manifestations include neurologic symptoms, carditis, ocular findings, and arthritis. A small proportion of Lyme patients may develop post-Lyme syndrome or chronic Lyme disease, which does not respond to additional antibiotics and presents clinicians a difficult challenge and may require further workup.

Wright et al. discuss treatment options for patients with early and late disease. They recommend oral doxycycline as first line treatment in early localized disease, while intravenous antibiotic regimens can be used in patients with neurologic, cardiac, and refractory arthritis symptoms.

Figure A is the classic erythema migrans rash, characteristic of Lyme disease.

Incorrect answers:
Answer 1: Arthritis sometimes develops as a result of disseminated Lyme disease. However, this patient has been started on appropriate antibiotics and is unlikely to develop disseminated disease.

Answer 2: Cardiovascular disease such as heart block sometimes develops as a result of disseminated Lyme disease. However, this patient has been started on appropriate antibiotics and is unlikely to develop disseminated disease.

Answer 3: Neurologic complications such as cerebritis and Bell palsy sometimes develops as a result of Lyme disease. However, this patient has been started on appropriate antibiotics thus limiting progression of their condition.

Answer 5: Borrelia burgdorferi is eradicated with appropriate antibiotic therapy and is not known to establish latency.

Bullet Summary:
Patients with early localized Lyme disease started on appropriate antibiotic therapy are unlikely to develop further complications of Lyme disease.