American Board of Internal Medicine (ABIM) Certification Practice Exam

What is the first-line treatment for Lyme disease with multiple erythema migrans?

1. Ceftriaxone

2. Oral doxycycline, amoxicillin, or cefuroxime axetil

3. Azithromycin

4. Metronidazole

The correct answer is: Oral doxycycline, amoxicillin, or cefuroxime axetil

The first-line treatment for Lyme disease with multiple erythema migrans is oral doxycycline, amoxicillin, or cefuroxime axetil. These antibiotics are effective because they target the bacteria responsible for Lyme disease, Borrelia burgdorferi, and are the preferred agents for treating early localized or early disseminated Lyme disease, which is characterized by the presence of multiple lesions. Doxycycline is especially favored for adults and children over eight due to its efficacy and the additional benefit of treating co-infections such as Anaplasma, which can be transmitted by the same ticks. Amoxicillin and cefuroxime axetil provide alternative options, catering to individuals who may not tolerate doxycycline, such as those with certain allergies or contraindications. Other options, such as ceftriaxone, while effective for serious or neurological manifestations of Lyme disease, are typically reserved for patients with more severe conditions or those requiring intravenous therapy. Azithromycin and metronidazole are not recommended as first-line treatments for Lyme disease because they lack efficacy against the Borrelia bacteria. Thus, the oral antibiotics mentioned are the standard care for managing the condition effectively in its early stages.