Choice of an oral beta-lactam antibiotic for infections due to penicillin-resistant Streptococcus pneumoniae.

The activity, pharmacokinetic and pharmacodynamic parameters of 5 oral beta-lactams have been compared against 400 penicillin-resistant Streptococcus pneumoniae (PRSP) isolated in 9 European countries. All the data have been calculated for the highest recommended oral dosage in France. Amoxicillin was by far the most effective antibiotic when considering its intrinsic activity (96% of the PRSP inhibited at 2 mg/l), the inhibitory quotient (100% of the PRSP > 1 vs 69.2% for cefuroxime) or a time above MIC > 40% which best correlates with clinical results (96% for amoxicillin vs < 25% for the cephalosporins).