Abstract：
OBJECTIVE: To ascertain the frequency of coinfections in Acanthamoeba keratitis, the nature of copathogens involved, and to analyze the implications in the context of current research on amoebic interactions.
METHODS: A retrospective case review from a Tertiary Care Eye Hospital in South India. Smear and culture data for coinfections in Acanthamoeba corneal ulcers were collected from records over a 5-year period. The significance and relevance of our findings in the light of current research on Acanthamoeba interactions were analyzed.
RESULTS: Eighty-five cases of culture-positive Acanthamoeba keratitis were identified over a 5-year period (43 of them being coinfections). Fusarium was most commonly identified species, followed by Aspergillus and the dematiaceous fungi. Pseudomonas spp was the commonest bacterial isolate.
CONCLUSIONS: Coinfections with Acanthamoeba are common at our centre, and account for 50% of Acanthamoeba keratitis. The diverse nature of the organisms involved in coinfections suggest that such amoebic interactions with other organisms are probably more widespread than recognized. To the best of our knowledge, this is the first documentation from a long-term study of pathogen diversity in Acanthamoeba coinfections. It is possible that Acanthamoeba itself may be virulence enhanced and secondary to the co-organism, breaching the ocular surface defenses in an already compromised cornea. However, observations from the existing literature on Acanthamoeba interactions with bacteria and certain fungi are based mainly on nonocular or nonclinical isolates. It would be illuminating if such studies are performed on Acanthamoeba and coinfectors from corneal ulcers-to ascertain whether interactions are endosymbiotic or virulence enhanced through amoebic passage.
METHODS: A retrospective case review from a Tertiary Care Eye Hospital in South India. Smear and culture data for coinfections in Acanthamoeba corneal ulcers were collected from records over a 5-year period. The significance and relevance of our findings in the light of current research on Acanthamoeba interactions were analyzed.
RESULTS: Eighty-five cases of culture-positive Acanthamoeba keratitis were identified over a 5-year period (43 of them being coinfections). Fusarium was most commonly identified species, followed by Aspergillus and the dematiaceous fungi. Pseudomonas spp was the commonest bacterial isolate.
CONCLUSIONS: Coinfections with Acanthamoeba are common at our centre, and account for 50% of Acanthamoeba keratitis. The diverse nature of the organisms involved in coinfections suggest that such amoebic interactions with other organisms are probably more widespread than recognized. To the best of our knowledge, this is the first documentation from a long-term study of pathogen diversity in Acanthamoeba coinfections. It is possible that Acanthamoeba itself may be virulence enhanced and secondary to the co-organism, breaching the ocular surface defenses in an already compromised cornea. However, observations from the existing literature on Acanthamoeba interactions with bacteria and certain fungi are based mainly on nonocular or nonclinical isolates. It would be illuminating if such studies are performed on Acanthamoeba and coinfectors from corneal ulcers-to ascertain whether interactions are endosymbiotic or virulence enhanced through amoebic passage.
摘要：
目的：确定棘阿米巴角膜炎合并感染的频率，涉及的共病原体的性质，并在当前阿米巴相互作用研究的背景下分析其含义。
方法：来自印度南部一家三级护理眼科医院的回顾性病例回顾。从5年的记录中收集了棘阿米巴角膜溃疡合并感染的涂片和培养数据。根据当前有关棘阿米巴相互作用的研究，分析了我们发现的意义和相关性。
结果：在5年的时间里发现了85例培养阳性棘阿米巴角膜炎（其中43例为合并感染）。镰刀菌是最常见的物种，其次是曲霉和脱毛真菌。假单胞菌属是最常见的细菌分离株。
结论：在我们中心，棘阿米巴共感染很常见，占50%的棘阿米巴角膜炎。参与共感染的生物体的多样性表明，这种阿米巴与其他生物体的相互作用可能比公认的更为广泛。据我们所知,这是对棘阿米巴共感染病原体多样性的长期研究的第一份文献。棘阿米巴本身可能是毒力增强和继发于共生物，在已经受损的角膜中破坏眼表防御。然而,现有文献中有关棘阿米巴与细菌和某些真菌相互作用的观察结果主要基于非眼部或非临床分离株。如果对角膜溃疡的棘阿米巴和coinfector进行此类研究，以确定相互作用是内共生还是通过阿米巴通过增强毒力，这将是有启发性的。
方法：来自印度南部一家三级护理眼科医院的回顾性病例回顾。从5年的记录中收集了棘阿米巴角膜溃疡合并感染的涂片和培养数据。根据当前有关棘阿米巴相互作用的研究，分析了我们发现的意义和相关性。
结果：在5年的时间里发现了85例培养阳性棘阿米巴角膜炎（其中43例为合并感染）。镰刀菌是最常见的物种，其次是曲霉和脱毛真菌。假单胞菌属是最常见的细菌分离株。
结论：在我们中心，棘阿米巴共感染很常见，占50%的棘阿米巴角膜炎。参与共感染的生物体的多样性表明，这种阿米巴与其他生物体的相互作用可能比公认的更为广泛。据我们所知,这是对棘阿米巴共感染病原体多样性的长期研究的第一份文献。棘阿米巴本身可能是毒力增强和继发于共生物，在已经受损的角膜中破坏眼表防御。然而,现有文献中有关棘阿米巴与细菌和某些真菌相互作用的观察结果主要基于非眼部或非临床分离株。如果对角膜溃疡的棘阿米巴和coinfector进行此类研究，以确定相互作用是内共生还是通过阿米巴通过增强毒力，这将是有启发性的。
