Hagan M, Wright E, Newman M, Dolin P, Johnson G
Korle Bu Teaching Hospital, University of Ghana, Accra, Ghana.
Br J Ophthalmol. 1995 Nov;79(11):1024-8. doi: 10.1136/bjo.79.11.1024.
Suppurative keratitis is a serious problem in all tropical countries, but very little information is available about the causative organisms in Africa. The objectives were to identify the causative organisms and the proportion of cases caused by fungi in southern Ghana, and to determine whether correct decisions about treatment could be made on the basis of Gram stain in the eye clinic.
Scrapings were taken from corneal ulcers of consecutive new patients presenting at Korle Bu Hospital, Accra, and inoculated on 'chocolate' and Sabouraud's agars. Further scrapings were taken for Gram staining and interpretation in the eye clinic. Duplicate slides were assessed by an experienced microbiologist in the UK.
One or more organisms were cultured from 114 of 199 patients (57.3%), the most common being Fusarium species, Pseudomonas aeruginosa, and Staphylococcus epidermidis. Fungi, alone or in combination, were isolated from 56% of the patients who had positive cultures. In total, 122 patients (61.3%) had their treatment either determined or altered based on the results of the microbiological diagnosis; in 87 of these solely on the basis of direct microscopic examination.
Infection by filamentous fungi accounted for more than half of the ulcers from which cultures were obtained. Both training in technique and experience in interpretation are necessary for microscopy based diagnosis by staff in the clinic to be of greatest value. Direct microscopy was particularly useful for detecting fungi.
化脓性角膜炎在所有热带国家都是一个严重问题，但关于非洲致病微生物的信息却非常少。目的是确定加纳南部化脓性角膜炎的致病微生物及其真菌所致病例的比例，并确定在眼科诊所能否根据革兰氏染色做出正确的治疗决策。
从阿克拉科勒布医院连续就诊的新患者角膜溃疡处取材，接种于“巧克力”琼脂和沙氏琼脂上。进一步取材用于革兰氏染色并在眼科诊所进行判读。重复玻片由英国一位经验丰富的微生物学家评估。
199例患者中有114例（57.3%）培养出一种或多种微生物，最常见的是镰刀菌属、铜绿假单胞菌和表皮葡萄球菌。在培养结果呈阳性的患者中，56%分离出真菌，单独或混合存在。总共有122例患者（61.3%）的治疗方案根据微生物学诊断结果确定或改变；其中87例仅基于直接显微镜检查。
丝状真菌感染占培养出微生物的溃疡病例的一半以上。诊所工作人员要想通过显微镜检查做出最有价值的诊断，技术培训和判读经验都必不可少。直接显微镜检查对检测真菌特别有用。
