巴基斯坦南部84例真菌性角膜炎的研究

摘要

AIM:To identify the predisposing factors,causative fungi and to improve the facilities for the laboratory diagnosis of fungal keratitis.METHODS:Two hundred and forty eyes of 240 patients of clinically suspected microbial corneal ulcer were included in the study.Data was collected through history and slit lamp examination.Using standard techniques,corneal scraping was performed.A portion of each scraping was examined by direct microscopy for the presence of fungi,bacteria and acanthamoeba by using 10% potassium hydroxide and also by Gram and Giemsa stainings.Another portion was inoculated directly on the surface of solid media such as Blood agar,Mac-Conkey agar,chocolate agar and Sabouraud agar in C-shaped streaks for culture.RESULTS:A total of 240 patients with suppurative corneaI ulcer were enrolled in the study,out of which fungi were identified in 84(35%)patients.Of these,48(57.1%)were males and 36(42.9%)females.The age ranged between 22-80 years.Sixty patients(71.4%)belonged to rural population and twenty four(28.6%)to urban population.Trauma with vegetative material was the most frequent cause noted in eighteen(21.4%)patients.Peak incidence was in the months of October-Nevember.Out of 84 eyes with fungal keratitis,fungi alone were the etiologic agents in 74(80.10%)cases and bacteria with fungi were identified in 10(11.90%).The most frequently isolated organism was Candida albicans which was found in 66(78.6%)patients.CONCLUSION:Fungal keratitis is the leading cause of infective corneal ulcer and Candida albicans being the most commonly isolated pathogen in the patients belonging to Southern Pakistan.The direct microscopic examination with potassium hydroxide 100mL/L method is a simple,rapid,inexpensive and reliable method in the diagnosis of this infection.%目的:确定真菌性角膜炎的易感因素、致病真菌,以及提高相应的实验室诊断能力.方法:240例240眼临床疑似微生物感染的角膜溃疡患者进入本研究.通过病史回溯及裂隙灯检查获得病例资料.采用标准技术完成角膜刮片检查.取部分刮片样本加入10%的氢氧化钾液后,以及采用革兰氏和吉姆萨染色,在直接在显微镜下观察是否存在真菌、细菌和棘阿米巴.另一部分刮片样本直接接种在血琼脂、麦康基琼脂、巧克力琼脂和萨布罗琼脂表面.结果:在纳入本研究的240例伴有脓性分泌物的角膜溃疡患者中,84例(35%)被确认为真菌感染.其中48例(57.1%)为男性,其余36例(42.9%)为女性.年龄分布从22-80岁.其中60例(71.4%)为农村患者,其余24例(28.6%)为城市居民.18例(21.4%)曾有植物外伤史.病变高发于10月至11月间.在84例确诊为真菌性角膜炎的患眼,致病原因为单纯真菌者74眼(80.10%),其余10眼(11.90%)为真菌合并细菌感染.分离得到的最常见致病微生物为白色念珠菌,在66眼(78.6%)中被发现.结论:在巴基斯坦南部,感染性角膜溃疡中,最常见的是真菌性角膜炎,而白色念珠菌是最常见的致病原.采用加入10%的氢氧化钾液后直接显微镜下观察是此类感染原简单、迅速、价廉及可信的诊断方法.