Efficacy of empirically prescribed amoxicillin and amoxicillin + clavulanic acid in children's reactive arthritis: a randomised trial.

OBJECTIVE: To evaluate the efficacy of early empiric prescription of amoxicillin and amoxicillin + clavulanic acid in children with reactive arthritis (ReA) when the arthritis-triggering microorganism is not identified. METHODS: 138 children, ranging in age from 2 to 16 years, with ReA of up to 3 months duration were randomly assigned to 3 groups and either prescribed antibacterial treatment with amoxicillin or amoxicillin + clavulanic acid (amoxicillin-potassium clavulanate combination) or were not given antibiotics (control group). Patients in all 3 groups were prescribed the usual treatment with nonsteroidal antiinflammatory drugs. Both groups of patients under antibacterial treatment were randomised into 2 subgroups: patients given a 10- to 14-day or a 28-day-duration antibacterial course. The results of the study were evaluated after 1 and 3 months of observation by determining the percentage of patients that had no clinical or laboratory signs of disease activity. RESULTS: After 1 month of observation no signs of disease activity were found in 48.0% of patients who were prescribed amoxicillin, in 58.5% of patients treated with amoxicillin + clavulanic acid, and only in 13.0% of patients from the control group (p < 0.001 for either antibacterial treatment in comparison with the control group). After 3 months of observation no disease activity was found in 92.0% of patients who used amoxicillin, in 95.1% of those treated with amoxicillin + clavulanic acid, and in 58.7% of children from the control group (p < 0.001 for either antibacterial treatment in comparison with the control group). There was no significant difference in the efficacy of amoxicillin and amoxicillin + clavulanic acid. The duration of the antibacterial course showed no influence on the results of treatment. CONCLUSION: Amoxicillin or amoxicillin + clavulanic acid in 10- to 14-day courses are advisable, in addition to the antirheumatic treatment, for children in the early stage of ReA when the arthritis-triggering microorganism is not identified.