Lainson Ralph, de Souza Manoel C, Franco Constância M
Departamento de Parasitologia, Instituto Evandro Chagas, Av. Almirante Barroso 492, 66090-000 Belém, PA, Brasil.
Mem Inst Oswaldo Cruz. 2003 Dec;98(8):1067-70. doi: 10.1590/s0074-02762003000800016.
Three different haematozoan parasites are described in the blood of the teiid lizard Ameiva ameiva Linn. from North Brazil: one in the monocytes and the other two in erythrocytes. The leucocytic parasite is probably a species of Lainsonia Landau, 1973 (Lankesterellidae) as suggested by the presence of sporogonic stages in the internal organs, morphology of the blood forms (sporozoites), and their survival and accumulation in macrophages of the liver. One of the erythrocytic parasites produces encapsulated, stain-resistant forms in the peripheral blood, very similar to gametocytes of Hemolivia Petit et al., 1990. The other is morphologically very different and characteristically adheres to the host-cell nucleus. None of the parasites underwent development in the mosquitoes Culex quinquefasciatus and Aedes aegypti and their behaviour in other haematophagous hosts is under investigation. Mixed infections of the parasites commonly occur and this often creates difficulties in relating the tissue stages in the internal organs to the forms seen in the blood. Concomitant infections with a Plasmodium tropiduri-like malaria parasite were seen and were sometimes extremely heavy.
在来自巴西北部的鞭尾蜥Ameiva ameiva Linn.的血液中发现了三种不同的血寄生虫：一种存在于单核细胞中，另外两种存在于红细胞中。根据内脏中孢子生殖阶段的存在、血液形态（子孢子）以及它们在肝脏巨噬细胞中的存活和积累情况，白细胞内的寄生虫可能是1973年的Lainsonia Landau属（兰克斯特鞭毛虫科）的一个物种。其中一种红细胞内的寄生虫在外周血中产生包囊化、抗染色的形态，与1990年的Hemolivia Petit等人描述的配子体非常相似。另一种在形态上有很大差异，其特征是附着在宿主细胞核上。这些寄生虫在致倦库蚊和埃及伊蚊中均未发育，它们在其他吸血宿主中的行为正在研究中。寄生虫的混合感染很常见，这常常给将内脏中的组织阶段与血液中所见形态联系起来带来困难。同时还发现了与一种类热带疟原虫的疟原虫同时感染的情况，有时感染程度极其严重。
