解脲脲原体是一种重要的病原微生物，近年来其耐药形势十分严峻，因此寻找一种全新的有效替代治疗方案尤为重要。本研究旨在探索光动力抗微生物化学疗法对解脲脲原体体外活性的影响。选取解脲脲原体两种生物群（Parvo生物群及T960生物群）代表菌株，包括标准株及临床株，与系列稀释的2.5~0.039 062 5 mmol/L光敏剂甲苯胺蓝孵育20 min或60 min，再以（633±10）nm红光照射，设置48、102、204和408 mJ/cm²共4组能量密度，48 h后判读结果。观察不同解脲脲原体与甲苯胺蓝孵育时间、甲苯胺蓝浓度、光照能量密度对光动力抗微生物化学疗法灭活解脲脲原体效果的影响，并观察两种生物群对光动力抗微生物化学疗法敏感性的差异。结果显示，光动力抗微生物化学疗法在体外对解脲脲原体有明显灭活作用。在光照能量密度及解脲脲原体与甲苯胺蓝孵育时间固定的前提下，这种灭活作用随甲苯胺蓝浓度的增加而增强；单一633 nm红光光源在408 J/cm²及以下的能量密度对解脲脲原体的活性无明显影响。在甲苯胺蓝浓度及解脲脲原体与甲苯胺蓝孵育时间固定的条件下，光动力抗微生物化学疗法对解脲脲原体的灭活作用随光照能量密度（48~408 mJ/cm²）的增加而增强；随甲苯胺蓝孵育时间（30~60 min）延长，光动力抗微生物化学疗法对解脲脲原体的灭活作用有增强的趋势。结果提示，解脲脲原体两种生物群对光动力抗微生物化学疗法的敏感性相似。本研究证实，光动力抗微生物化学疗法在体外能有效灭活解脲脲原体，有望成为解脲脲原体感染的有效替代治疗方法。

Ureaplasma urealyticum (U. urealyticum) is a very important pathogenic microorganism. In view of a worsen resistance of U. urealyticum to antibiotics recently, it’s in great need to exploit new alternative therapies for U. urealyticum infections. The aim of this research is to study the in vitro susceptibility of U. urealyticum to toluidine blue-mediated photodynamic antimicrobial chemotherapy (PACT). Two biovars of U. urealyticum including two standard strains and two clinical strains were incubated with photosensitizer toluidine blue with different concentrations from 2.5 to 0.039 062 5 mmol/L. After 20 or 60 min incubation, they were treated with (633±10) nm red light source, with four different light fluences including 48, 102, 204 and 408 mJ/cm². The association between the incubation time, toluidine blue concentration, as well as the light fluence and PACT effect on U. urealyticum was evaluated 48 h after treatment. Besides, the difference in response to PACT between the two biovars of U. urealyticum was also analyzed. The results showed that PACT had an inactivation effect on the growth of U. urealyticum, in a toluidine blue concentration-dependent and fluence-dependent manner. Longer incubation time induced more extensive inactivation of U. urealyticum. No significant difference in susceptibility to PACT was observed between the two biovars of U. urealyticum. It is concluded that toluidine blue-mediated PACT can inactivate U. urealyticum in vitro, and this therapy may become a promising alternative treatment for U. urealyticum infections.