Acanthamoeba spp. are free-living amebae that inhabit a variety of air, soil, and water environments. However, these amebae can also act as opportunistic as well as nonopportunistic pathogens. They are the causative agents of granulomatous amebic encephalitis and amebic keratitis and have been associated with cutaneous lesions and sinusitis. Immuno compromised individuals, including AIDS patients, are particularly susceptible to infections with Acanthamoeba. The immune defense mechanisms that operate against Acanthamoeba have not been well characterized, but it has been proposed that both innate and acquired immunity play a role. The ameba's life cycle includes an active feeding trophozoite stage and a dormant cyst stage. Trophozoites feed on bacteria, yeast, and algae. However, both trophozoites and cysts can retain viable bacteria and may serve as reservoirs for bacteria with human pathogenic potential. Diagnosis of infection includes direct microscopy of wet mounts of cerebrospinal fluid or stained smears of cerebrospinal fluid sediment, light or electron microscopy of tissues, in vitro cultivation of Acanthamoeba, and histological assessment of frozen or paraffin-embedded sections of brain or cutaneous lesion biopsy material. Immunocytochemistry, chemifluorescent dye staining, PCR, and analysis of DNA sequence variation also have been employed for laboratory diagnosis. Treatment of Acanthamoeba infections has met with mixed results. However, chlorhexidine gluconate, alone or in combination with propamidene isethionate, is effective in some patients. Furthermore, effective treatment is complicated since patients may present with underlying disease and Acanthamoeba infection may not be recognized. Since an increase in the number of cases of Acanthamoeba infections has occurred worldwide, these protozoa have become increasingly important as agents of human disease.

中文翻译：

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棘阿米巴属 作为人类疾病的媒介。

棘阿米巴属 是居住在各种空气，土壤和水环境中的自由生活的变形虫。但是，这些变形虫也可以作为机会性病原体和非机会性病原体。它们是肉芽肿性阿米巴性脑炎和阿米巴性角膜炎的病原体，并与皮肤病变和鼻窦炎有关。免疫受损的个体，包括艾滋病患者，尤其容易受到棘阿米巴感染的影响。针对棘阿米巴的免疫防御机制尚未得到很好的表征，但已提出先天和后天免疫均起着作用。变形虫的生命周期包括活跃的营养滋养子阶段和休眠的囊肿阶段。滋养体以细菌，酵母和藻类为食。然而，滋养体和囊肿均可保留活菌，并可作为具有人类致病潜能的细菌的贮藏库。感染的诊断包括直接显微镜检查湿的脑脊髓液坐骑或脑脊液沉积物的涂片涂片，组织的光镜或电镜检查，棘阿米巴的体外培养以及对冷冻或石蜡包埋的脑或皮肤病变活检材料的切片的组织学评估。免疫细胞化学，化学荧光染料染色，PCR和DNA序列变异分析也已用于实验室诊断。棘阿米巴感染的治疗取得了好坏参半的结果。但是，葡萄糖酸氯己定单独或与丙硫基羟乙磺酸盐联用对某些患者有效。此外，有效的治疗很复杂，因为患者可能患有基础疾病，而棘阿米巴感染可能无法被识别。由于全世界范围内发生了棘阿米巴感染病例的增加，这些原生动物作为人类疾病的传播者变得越来越重要。