RESUMEN
<p><b>OBJECTIVES</b>To study the antibacterial effect of Niaoluqing Oral Liquid (NOL) on clinical drug-resistant strains and 14 serotype strains Ureaplasma Urealyticum (UU).</p><p><b>METHODS</b>Sixty-three clinical strains of UU were detected to determine their serology and antibiotic susceptibilities by the metabolic inhibition test (MIT). Mininum inhibitory concentration (MIC) was used to evaluate the sensitivity of NOL to different serotypes of UU. The sensitivity of NOL, erythromycin and tetracycline to 63 clinical strains of UU was also studied.</p><p><b>RESULTS</b>In 63 clinical strains of UU, the range of MIC to NOL was from 0.48 mg/ml to 15.63 mg/ml, MIC50 < or = 1.95 mg/ml, MIC90 < or = 3.91 mg/ml. Among them, 31 strains were resistant to tetracycline and 31 were resistant to erythromycin. No obvious correlation between the sensitivity of NOL to UU clinical strains and that of erythromycin and tetracycline to UU clinical strains (P > 0.05). Clinical strains of UU in this experiment contains all of its serotypes, also having a higher sensitivity to NOL (MIC < or = 3.91 mg/ml) except serology 1, 2, 3 and 11 (MIC > or = 7.81 mg/ml).</p><p><b>CONCLUSIONS</b>NOL exerts a strong in vitro antibacterial effect on erythromycin-resistant and tetracycline-resistant clinical strains of UU. All kinds of serotype strains had a higher sensitivity to NOL, too. Chinese medicinal herbs are of momentous significance in the treatment of UU infection.</p>