棘阿米巴角膜炎致病虫株的超微结构观察  

Ultrastructure study of pathogen of acanthamoeba keratitis

作　　者：罗时运[1] 金秀英[1] 王智群[1] 李然[1] 殷晓棠[1] 王民[2] 孙旭光[1] 

机构地区：[1]首都医科大学附属北京同仁医院北京同仁眼科中心北京市眼科研究所,100005 [2]首都医科大学电镜室

出　　处：《中华眼科杂志》2008年第11期1020-1024,共5页Chinese Journal of Ophthalmology

摘　　要：目的探讨氯己定（洗必泰）对棘阿米巴角膜炎患者角膜内分离培养虫株的作用，为临床治疗棘阿米巴角膜炎提供实验室依据。方法实验研究。利用扫描电镜观察分离培养虫株的形态特征以及0．02％氯己定作用后的结构变化；利用透射电镜观察角膜病变组织内棘阿米巴的超微结构特征。结果体外培养的棘阿米巴滋养体大小约15～45μm呈圆形、椭圆形、不规则形状，虫体体表粗糙，有棘状胞质突起，以二分裂方式繁殖。包囊大小约10～25μm，球形，表面见皱襞、壁孔及圆形孔盖。棘阿米巴自壁孔处逸出转变成滋养体，脱囊后遗留空囊。经0．02％氯己定作用24h后的滋养体和包囊结构被破坏，虫体崩解成残膜碎片或凝块、颗粒状。经过抗棘阿米巴治疗后的角膜病变组织内未见滋养体，仅见包囊。包囊内外壁结构基本保留，但细胞质蛋白凝固，亚细胞结构退变缺失，包囊处于变性失活状态。结论0．02％氯己定在体外可杀灭棘阿米巴滋养体和包囊，在组织内可杀灭棘阿米巴滋养体，致包囊变性失活。变性失活的棘阿米巴包囊仍可较长时间存留在角膜组织中，并可引发免疫病理性炎性反应，临床治疗中应引起注意。Objective To observe the ultrastructure of the strains of acanthamoeba isolated from acanthamoeba keratitis （AK）, the morphologic changes of acanthamoeba after culture with 0. 02% chlorhexidine, and uhrastructure characteristics of acanthamoeba in corneal tissue of AK. Methods It was a experimental study. The uhrastructure of acanthamoeba strains cultured with 0.02% chlorhexidine was observed with scanning electron microscope （SEM）. The excited cornea tissues from AK were observed with transmission electron microscope （TEM）. Results Cultured acanthamoeba trophozoites were approximately 15-45 μm in diameter, appeared irregularly round or oval in shape, with rough surface and intrusion of cytoplasm. The trophozoite propagated by ways of binary division. The acanthamoeba cysts were approximately 10-25 μm in diameter, round in shape and with a plica-like surface. The acanthamoeba could change from trophozoite to cyst. The amoeba emerging through ostioles could turn into trophozoite and left an empty cyst. After cultured with 0.02% chlorhexidine for 24 hours, the trophozoite and cyst collapsed and distorted. However, after clinical treatment with 0. 02% chlorhexidine, only the cysts could be seen in corneal tissue of AK. Ectro-and endo-cystic walls were preserved, but the cytoplasma was aggregated and the sub-cytoarchitectures were degenerated or disappeared. Discussion Chlorhexidine at a concentration of 0.02% kills acanthamoeba trophozoites and cysts in vitro. Chlorhexidine （0. 02% ） also kills trophozoites and inhibits the activity of cysts in corneal tissues. However, it should be noticed that the inactive cysts can stay in the cornea for a long time and may cause an immuno-pathologic inflammation of the cornea.

关 键 词：棘阿米巴属 角膜炎 显微镜检查 电子 扫描 显微镜检查 电子 透射 

分 类 号：R686[医药卫生—骨科学]