The tick-borne spirochete responsible for
Lyme disease is highly antibiotic-sensitive. Treatment related misconceptions can be attributed to confusion in three principal realms: (1) the appropriate approach to diagnosis (who should be treated); (2) necessary and appropriate treatment; and (3) what actually constitutes nervous system infection and to what extent this mandates different treatment. Contrary to often-repeated assertions, laboratory-based diagnosis-in the appropriate setting-is as valid as it is in most other serologically diagnosed infections. Treatment is highly effective in the vast majority of patients, including those with nervous system
disease. Nervous system infection, most typically meningitis, cranial neuritis, radiculoneuritis, and other forms of mononeuropathy multiplex, is highly antibiotic responsive. The encephalopathy that can be seen in some patients with active infection represents the same phenomenon that occurs in patients with many other inflammatory disorders, is not evidence of central nervous system (CNS) infection, and does not require any different, more prolonged, or more intensive treatment. In patients with infection not involving the CNS, oral treatment with amoxicillin, cefuroxime axetil, or doxycycline for 2-4 weeks is almost always curative. Despite historic preferences for parenteral treatment with ceftriaxone, cefotaxime, or meningeal dose penicillin, patients with the forms of nervous system involvement listed above are highly responsive to oral doxycycline. Parenteral regimens can be reserved for those very rare patients with parenchymal CNS involvement, other severe forms of infection, or the approximately 5 % of patients who fail to respond to oral regimens.