Antimicrobial susceptibility of Chlamydia pneumoniae isolates from children and their families

Eighteen isolates of Chlamydia pneumoniae from ill children with bronchitis and/or pneumonia and their families were tested in terms of susceptibility to antimicrobial agents. (These strains were isolated from May 1992 to December 1995). The antibiotics used were doxycline (DOXY), erythromycin (EM), rokitamycin (RKM), azithromycin (AZM), clarithromycin (CAM), roxithromycin (RXM) and ofloxacin (OFLX). The MIC ranges of these antibiotics against the isolates wee 0.03~0.125 μg/ml except OFLX (0.5~2.5 μg/ml), and the MICs were similar to those for C. pneumoniae TW 183 and C. trachomatis serovar L2. The minimal chlamydiacidal concentration was also determined by using 10 isolates for which the concentration was about 10 times higher than the MIC. No difference was found among the isolates from the same patients.