In vitro antibacterial activities of telithromycin against clinical isolates of Neisseria gonorrhoeae

In vitro antibacterial activity of telithromycin (TEL) against the isolates of Neisseria gonorrhoeae (212 isolates) derived from urine or genital secretion in 2002 (April to December) was examined in comparison with those of macrolides (erythromycin [EM], clarithromycin [CAM]), penicillins (penicillin G [PCG]), cephems (cefodizime [CDZM], cefixime [CFIX]), quinolones (levofloxacin [LVFX]), tetracyclines (minocycline [MINO]), and aminoglycosides (spectinomycin [SPCM]). The MIC of TEL was ranged from < or = 0.039 to 0.25 microg/mL and the MIC50 and MIC90 of TEL were respectively 0.125 and 0.25 microg/mL, which were the lowest values compared with those of other oral antibacterial agents measured. When compared TEL with other agents in the order of the MIC50 and MIC90, TEL was more superior to EM and CAM (both eight times), MINO (four times and twice), and LVFX (16 and 64 times). The MIC90 of TEL was superior in twice though the MIC50 was the same in comparison with CFIX. The CDZM resistant strain did not exist and SPCM also inhibit growth with 32 microg/mL or less that was the breakpoint MIC excluding one stock though the PCG sensitive strain was only 1.4% in the injection drug. However, clinical breakpoint MIC is not established, but the efficacy of TEL is prospective because of its high antibacterial activity to inhibit growth of all stocks for gonococcus with 0.25 microg/mL. It is expected that TEL can become an oral antibiotic recommended for treatment of gonococcus if dosage and administration are considered.