A commentary on the treatment of early lyme disease.

The question of how long to treat Borrelia burgdorferi infection is a topic that provokes confusion among a large number of physicians. As pointed out by Kowalski et al [1] in this issue of Clinical Infectious Diseases, many physicians tend to use longer courses of antibiotics for Lyme disease than they would for other bacterial infections. A few physicians advocate prolonged courses of antibiotics, claiming that Lyme disease is responsible for an array of vague subjective clinical concerns and a cause of chronic infection [2, 3]. One has to question why a reasonable physician would treat a patient this way and more importantly what has led to this confusion. In large part, one can look to the treatment trials of Lyme disease for an answer. How Lyme disease is defined and how “cure” is determined stands at the crux of the issue. The only clinical manifestation of B. burgdorferi infection that is diagnostic is erythema migrans (EM), a characteristic skin lesion associated with early infection [4, 5]. In contrast to most bacterial diseases in which infection is defined microbiologically by direct observation,