Aim of the study: To compare clinical effectiveness and safety of treatment with clarithromycin and amoxicillin in children with solitary erythema migrans (EM).
Methods: Consecutive patients younger than 15 years, referred to our institution in 2004 and 2005 with previously untreated solitary erythema migrans, were included in this prospective study. Basic demographic features and clinical data were collected by means of a questionnaire. The efficiency of treatment of acute disease, development of later major and/or minor manifestations of Lyme borreliosis (LB), and side effects of treatment were surveyed by follow-up visits during the first year after the initiation of antibiotic treatment.
Results: The study included 68 female and 67 male children patients. The median age of the patients was 6.5 years. Out of 135 patients, 66 received clarithromycin and 69 amoxicillin. Before treatment no differences in demographic and clinical characteristics between the two groups were observed. The mean duration of EM after the beginning of treatment was 4 days in both groups. Associated symptoms during treatment were present for 7 days in patients treated with clarithromycin and for 10 days in patients receiving amoxicillin (p = 0.188). Minor manifestations of LB were identified in 11 (22.0 %) of 50 patients receiving clarithromycin, and in 16 (29.6 %) of 54 patients receiving amoxicillin who remained in the study during the entire observation period. Major manifestations of LB were not identified in any patient treated with clarithromycin, while there were 2 (3.7 %) patients with major manifestations of LB, who were receiving amoxicillin. Side effects of treatment were identified in 24.2 % patients receiving clarithromycin and 28.1 % patients treated with amoxicillin (p = 0.761). Presence of the Jarisch-Herxheimer's reaction at the beginning of treatment was comparable in both groups (10.6 % and 10.3 %;p = 0.823).
Conclusion: Clarithromycin and amoxicillin are equally effective and safe in treatment of children with solitary EM and have comparable side effects.