光动力疗法(photodynamic therapy，PDT)利用光敏剂与光源反应后产生的活性氧，破坏细菌组分，进而致细菌死亡。其多靶位杀伤特性在治疗耐甲氧西林金黄色葡萄球菌(methicillin-resistant Staphylococcus aureus，MRSA)感染方面有应用前景，但相关研究尚处于起步阶段。本研究MRSA菌株取自烧伤、急性咽炎、鼻窦炎和肺炎4类临床常见MRSA感染性疾病患者，使用5-氨基酮戊酸(5-aminolevulinic acid，ALA)光敏剂、发光二极管光源，于体外检测ALA介导的PDT(ALA-PDT)对MRSA菌株的杀伤作用。结果显示，经5 mmol/L ALA孵育1 h后，给予360 J/cm²强光〔(633±10)nm〕照射1 h，ALA-PDT对MRSA菌株具有1.80 log₁₀ cfu的有效杀伤作用。结果提示，在相同实验条件和参数下，ALA-PDT对上述4种疾病来源的MRSA菌株体外杀伤作用无统计学差异。

In photodynamic therapy (PDT), the reactive oxygen species generated by the activation of photosensitizers by light of an appropriate wavelength, are able to inactivate microbes by damaging various microbial components. Due to its multi-targeting antimicrobial capability, PDT has shown a potential as an effective alternative therapeutic option against methicillin-resistant Staphylococcus aureus (MRSA). In this study, MRSA strains isolated from burn, acute pharyngitis, nasosinusitis and pneumonia patients were subjected to a 5-aminolevulinic acid (ALA) mediated light emitting diode (LED) array in vitro. The results showed that a significant reduction (1.8 log₁₀ cfu) was achieved with an ALA treatment (1 h, 5 mmol/L) followed by 1 h of illumination [(633±10) nm wavelength light source, and a 360 J/cm² light dose]. MRSA strains collected from different tissues showed a similar sensitivity to the treatment.