[Histopathology of protozoa]

Protozoa are single-celled animals hosted by animals and humans. Numerous parasites can be considered to be non-pathogenic for humans but, in tropical countries, pathology caused by protozoa is a major public health problem. The study of parasitic protozoa in tissues has provided fertile ground for investigation. In practical diagnosis, this test is useful when the parasite is not eliminated in stools or absent in the blood. This review considers all the morphological criteria allowing an accurate identification of species. The new infectious agents, recently emerged with HIV infection are analysed by simple technical procedures for their identification.