Visvesvara G S, Schuster F L, Martinez A J
Parasitic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia 30341-3724.
J Eukaryot Microbiol. 1993 Jul-Aug;40(4):504-14. doi: 10.1111/j.1550-7408.1993.tb04943.x.
We recently reported the isolation of a leptomyxid ameba from the brain of a mandrill baboon that died of meningoencephalitis. Based on light and electron microscopic studies, animal pathogenicity tests, and immunofluorescence patterns, we conclude that our isolate differs fundamentally from the other two amebas (Leptomyxa and Gephyramoeba) included in the Order Leptomyxida. We therefore created a new genus, Balamuthia, to accommodate our isolate and described it as Balamuthia mandrillaris to reflect the origin of the type species. Briefly, B. mandrillaris is a pathogenic ameba that causes amebic encephalitis in humans and animals. It has trophic and cyst stages in its life cycle, and is uninucleate with a large vesicular nucleus and a central nucleolus. Mature cysts have a tripartite wall consisting of an outer loose ectocyst, an inner endocyst and a middle mesocyst. Unlike Acanthamoeba and Naegleria, the other two amebas that cause amebic encephalitis in humans, Balamuthia will not grow on agar plates seeded with enteric bacteria. However, Balamuthia grows on a variety of mammalian cell cultures and kills mice following intranasal or intraperitoneal inoculation. Based on immunofluorescence testing, 35 cases of amebic encephalitis in humans and three in other animals have been identified worldwide as being caused by Balamuthia.
我们最近报告了从一只死于脑膜脑炎的山魈狒狒大脑中分离出一种纤毛黏液阿米巴。基于光学显微镜和电子显微镜研究、动物致病性试验以及免疫荧光模式，我们得出结论，我们分离出的菌株与纤毛黏液目（Leptomyxida）中包含的其他两种阿米巴（Leptomyxa和Gephyramoeba）有根本区别。因此，我们创建了一个新属——巴拉姆希阿米巴属（Balamuthia）来容纳我们分离出的菌株，并将其描述为曼氏巴拉姆希阿米巴（Balamuthia mandrillaris）以反映模式种的来源。简而言之，曼氏巴拉姆希阿米巴是一种致病性阿米巴，可导致人类和动物发生阿米巴性脑炎。它在生命周期中有滋养体和包囊阶段，单核，有一个大的泡状核和一个中央核仁。成熟包囊有三层壁，由外层疏松的外囊、内层的内囊和中间的中囊组成。与引起人类阿米巴性脑炎的另外两种阿米巴——棘阿米巴属（Acanthamoeba）和耐格里属（Naegleria）不同，巴拉姆希阿米巴不会在接种肠道细菌的琼脂平板上生长。然而，巴拉姆希阿米巴能在多种哺乳动物细胞培养物上生长，并在经鼻内或腹腔接种后杀死小鼠。基于免疫荧光检测，全世界已确认35例人类阿米巴性脑炎病例和3例其他动物的病例是由巴拉姆希阿米巴引起的。
