Giardia lambHa

8-19 nm; usual range: 11-14 |im; width, 7-10 pm

Oval, ellipsoidal, or may appear round

4; not distinct in unstained preparations; usually located atone end

Longitudinal fibers In cysts may be visible In unstained preparations; deep staining median bodies usually lie across the longitudinal fibers; there Is often shrinkage and the cytoplasm pulls away from the cyst wall; there may also be a "halo" effect around the outside of the cyst wall as a result of shrinkage caused by dehydrating reagents


6-10 nm; usual range: 7-9 (im; width, 4-6 nm

Lemon shaped with anterior hyaline knob

1; not distinct in unstained preparations

Cytostome with supporting fibrils, usually visible in stained preparation; curved fibril along side of cytostome usually referred to as "shepherd's craft"

Enteromonas hominis

4-10 pm; usual range: 6-8 nm; width, 4-6 (im

Elongate or oval

1-4; usually 2 lying at opposite ends of cyst; not visible in unstained mounts

Resembles £ nana cyst; fibrils orflagella usually not seen

Retortamonas intestinalis

4-9 urn; usual range: 4-7 pm; width, 5 urn

Pear shaped or slightly lemon shaped

1; not visible In unsigned mounts

Resembles Cttfomastorcyst; shadow outline of cytostome with supporting fibrils extends above nucleus; bird beak fibril arrangement

Figure 49-16 I, Trophozoite of Entamoeba histolytica (note ingested red blood cells). 2, Trophozoite of Entamoeba histolytica/Entamoeba dispar (morphology does not allow differentiation between the two species). 3 and 4, Early cysts of E. histolytica/E. dispar. 5 to 7, Cysts of E. histolytica/E. dispar.

figure 49-16 (cont'd) 8 and 9, trophozoites of Entamoeba coli. 10 and 11, Early cysts of E. coll 12 to 14, Cysts of E. coli, 15 and 16, Trophozoites of E. hartmanni. 17 and 18, Cysts of E. hartmanni (From Garcia LS: Diagnostic medical parasitology, ed 3, Washington, DC, 2007, ASM Press. Illustrations 4 and 11 by Nobuko Kitamura.)

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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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