In vitro activity of cefditoren against clinical isolates of penicillin-susceptible and penicillin-intermediate strains of Streptococcus pneumoniae isolated in Germany, 1992-1998.

This study investigates the susceptibility to cefditoren of penicillin-susceptible strains of invasive Streptococcus pneumoniae (n = 312) and of penicillin-intermediate strains of S. pneumoniae (n = 30) isolated mainly from patients with respiratory tract infections. The MIC(90)s of penicillin-susceptible and -intermediate isolates were as follows: cefditoren, < or =0.06 and 1 mg/L; penicillin G, < or =0.06 and 0.5 mg/L. Cefditoren showed the highest activity against the penicillin-intermediate strains investigated compared with the other beta-lactam antibiotics and is therefore considered to be a promising agent for the treatment of infections caused by pneumococci with reduced penicillin susceptibility.