双相性马尔尼菲青霉菌的体外药敏试验研究

Susceptibility study on diphasic form of Penicillium marneffei to the antifungal agents in vitro

比较马尔尼菲青霉菌(Penicilliummarneffei,PM)分别在25℃菌丝相和37℃酵母相时的MIC值,研究PM菌丝相和酵母相的相位改变对药物敏感性的影响。采用M27-p方案中的E-test法测定6株PM分别在25℃菌丝相(mycelial)和37℃酵母相(yeast)时对伊曲康唑、酮康唑、氟康唑、5-氟胞嘧啶、两性霉素B等5种药物的MIC值。25℃菌丝相时伊曲康唑、酮康唑、5-氟胞嘧啶、氟康唑、两性霉素B的MIC值范围分别为:0.002～0.032μg/mL、0.016～0.19μg/mL、0.008～0.19μg/mL、1.0～8.0μg/mL、0.125～6.0μg/mL,仅两性霉素B出现耐药株各2株。37℃酵母相时伊曲康唑、酮康唑、5-氟胞嘧啶、氟康唑、两性霉素B的MIC值范围分别为:0.002～0.75μg/mL、0.012～0.125μg/mL、0.012～0.25μg/mL、1.5～6.0μg/mL、0.047～2.0μg/mL,对氟康唑耐药株1株,5-氟胞嘧啶和两性霉素B出现耐药株各2株。结果示伊曲康唑敏感性最强,其次是酮康唑和5-氟胞嘧啶,两性霉素B敏感性最弱。PM在25℃菌丝相和37℃酵母相时对抗真菌药物敏感性存在差异,但菌丝相和酵母相的相位改变不影响其敏感性。

To compare the MIC values between the mycelial form and yeast form and to study whether the tempera ture and form can influence the antifungal susceptibilities,according to the E-test method of NCCLS M27-p document ,the MIC of mycelial form at25℃and yeast form at37℃of6Penicillium marneffei(PM)strains to5antifungal agents(itraconazole,keto-conazole,fluconazole,5-fluorocytosine,amphotericin B)was acquired.The MIC ranges of itraconazole,ketoconazole,5-fluo-ro cyto sine,fluconazole and amphotericin B on mycelial form were0.002-0.032μg /mL,0.016-0.19μg /mL,0.008-0.19μg /mL,1.0-8.0μg /mL and0.125-6.0μg /mL respectively only there were3resistant strains on amphotericin B.The MIC ranges of i-tra conazole,ketoconazole,5-fluorocytosine,fluconazole and amphotericin B on yeast forms were0.002-0.75μg /mL,0.012-0.125μg /mL,0.012-0.25μg /mL,1.5-6.0μg /mL and0.047-2.0μg /mL respectively,there were2resistant strains on5-fluorocy-to sine and amphotericin B and1resistant strain on fluconazole.The results suggested that the susceptability to itraconazole was su perior to the other4antifungal agents,next were ketoconazole and5-fluorocytosine,by contrast,amphotericin B was the least suscep tible.The susceptabilities of mycelial and yeast of PM to the above mentioned antifungal agents were dif fer-ent.How ever,the temperature and form of PM did not affect the susceptibility.