BACKGROUND: Pharyngotonsillitis (PT) caused by group A beta hemolytic streptococci (GABHS) is one of the most common infections of childhood. Two antibiotic suspensions, cefaclor (CEF) and amoxicillin/clavulanate (AMC), are commonly used in Poland for the treatment of PT caused by GABHS in children. MATERIAL/METHODS: This multi-center, randomized, single-blinded study was undertaken in order to compare the efficacy and safety of CEF (20 mg/kg/d) and AMC (25 mg/kg/d) in 10 days treatment of GABHS-related PT. 100 children (mean age 6 years) were enrolled into the study. Clinical and bacteriological assessments were done on the 14-18 th, and 38-45 th days after randomization. RESULTS: No GABHS strain isolated from throat smears was resistant in vitro to both antibiotics. Both antibiotics had almost 98% effectiveness at the post therapy visit. On follow-up, significantly more relapses and recurrences were observed in the AMC-treated group than in the CEF-treated group (relapse rate 21.28% vs 15.56%, p<0.02, recurrence 10.64% vs 6.66%, p<0.002). The relapse odds ratio in the AMC group was 1.7 times greater than in the CEF group, and recurrence was 1.5 times higher. There were significantly higher rates of gastrointestinal adverse events in children treated by AMC (p<0.02). CONCLUSIONS: CEF provides a clinically and bacteriologically effective treatment for children with PT caused by GABHS, comparable to AMC but significantly safer in terms of gastrointestinal side effects. AMC shows a greater risk of relapse and recurrence than CEF.

Keywords: Amoxicillin-Potassium Clavulanate Combination - therapeutic use, Cefaclor - adverse effects, Cefaclor - therapeutic use, Drug Therapy, Combination - adverse effects, Drug Therapy, Combination - therapeutic use