Figure 49-26 Top, Endolimax nana trophozoite. Bottom left, E. nana cyst. Bottom right, E. nana cyst.


Figure 49-27 A, Trophozoites of lodamoeba butschlii. B and C, Cysts of /. biitschlii.


Figure 49-27 A, Trophozoites of lodamoeba butschlii. B and C, Cysts of /. biitschlii.

Figure 49-28 Top, lodamoeba biitschlii trophozoites. Bottom left, lodamoeba biitschlii cyst. Bottom right, I. biitschlii cyst.

this group; their diagnosis is discussed in the following section. Members of the coccidian genera—Isospora, Cryptosporidium, and Cyclospora—can be found in the intestinal mucosa and other tissues. These organisms :iave been seen with increasing frequency in specimens from immunosuppressed patients, particularly those with AIDS (see Table 49-18).

Isospora, Cryptosporidium, and Cyclospora parasites are passed in the stool as oocysts; the other members of the protozoa exist in the intestinal tract in the trophozoite or cyst stages. Humans are generally infected with the coccidian parasite, Toxoplasma gondii, from the ingestion of infected meats, although its life cycle includes stages in animal hosts within the cat family and oocyst ingestion is also a potential route of infection (see Figure 49-12). The organisms can be seen in routine histologic tissue preparations, and the disease itself is normally diagnosed using serologic tests for antibody.

Isospora belli infects humans and diagnosis is based on finding the oocysts in the stool, primarily in the concentration sediment. These oocysts are immature when passed and will stain using modified acid-fast

Undulating membrane



Cytostomal groove

"Shepherd's crook"

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Bacterial Vaginosis Facts

Bacterial Vaginosis Facts

This fact sheet is designed to provide you with information on Bacterial Vaginosis. Bacterial vaginosis is an abnormal vaginal condition that is characterized by vaginal discharge and results from an overgrowth of atypical bacteria in the vagina.

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