Shadow outline of cytostome with supporting fibrils extends above nucleus. Fibrils or flagella are usually not seen. Cytoplasm often retracts from a portion of cell wall.ġ-4, usually 2 lying at opposite ends of cyst. Deep staining fibers or fibrils may be seen lying laterally or obliquely across fibrils in lower part of cyst. Usually located at one end.įibrils or flagella longitudinally in unstained cysts. Not visible in unstained preparations.Ĭytostome with supporting fibrils. *Not a practical feature for identification of species in routine fecal examinations Table 6: Differential Morphology of Protozoa Found in Stool Specimens of Humans: Flagellates-Cystsġ.

Prominent cytostome extending approximately 1/2 length of body. Posterior flagellum extends free posteriorly or laterally. Median bodies lying horizontally or obliquely in lower part of body. Sucking disk occupying 1/2-3/4 of ventral surface. Prominent cytostome extending 1/3-1/2 length of body. Undulating membrane extending length of body. Table 5: Differential Morphology of Protozoa Found in Stool Specimens of Humans: Flagellates-Trophozoites are not present.Ĭompact, well-defined mass. Occasionally granules present, but chromatoid bodies as seen in Entamoeba spp. Refractile, achromatic granules on one side of karyosome. Ovoidal, ellipsoidal, triangular, or other shapes. Concentrated mass seen occasionally in young cysts. Occasionally granules or small oval masses seen, but bodies as seen in Entamoeba spp. Mass stains lightly with iodine.įour in mature cysts not seen in unstained preparations A dark area called an “inclusion mass” (possibly concentrated cytoplasm) is often also present. Usually small, diffuse masses stain reddish brown with iodine. Many small bodies with angular or pointed ends, or few large ones. Usually fine granules evenly distributed. Occasionally visible in unstained preparations. Usually diffuse, but, occasionally well defined mass in immature cysts. Present, but less frequently seen than in E. Large, discrete, usually eccentric but occasionally centrally located. Coarse granules irregular in size and distribution, but often appear more uniform than in trophozoites. Immature cysts with 2 or more occasionally seen. Occasionally super-nucleated cysts with 16 or more are seen. Occasionally oval, triangular, or other shapes.Ĩ in mature cyst. Stains reddish brown with iodine.Ĥ in mature cyst. Concentrated mass often present in young cysts. Elongated bars with bluntly rounded ends. Small, discrete, usually centrally located. Fine, uniform granules, evenly distributed. Immature cysts with 1 or 2 occasionally seen. Table 4: Differential Morphology of Protozoa Found in Stool Specimens of Humans: Amoebae-CystsĤ in mature cyst. (In approximately 20% of organisms only 1 nucleus is present.) Nuclei invisible in unstained preparations. Pseudopods are angular, serrated, or broad lobed, and hyaline, almost transparent. These granules are often not distinct even in stained slides. Surrounded by refractile, achromatic granules. Not usually visible in unstained preparations. Visible occasionally in unstained preparations. Sluggish, usually nonprogressive with blunt pseudopods. Occasionally large, diffuse or irregular.Ĭoarsely, granular, may resemble E. Chromatin sometimes in plaques or crescents. Occasionally granules may be irregularly arranged. Occasionally may be irregularly distorted by pressure from vacuoles in cytoplasm. May be slightly visible in unstained preparations. Occasionally, in diarrheic specimens, motility may be progressive. Sluggish, nonprogressive, with blunt pseudopods.Ĭoarse granules, irregular in size and distribution. Usually nonprogressive but may be progressive occasionally. Noninvasive organisms may contain bacteria. Usually centrally located, but occasionally is eccentric. Usually evenly distributed and uniform in size. Progressive with hyaline, finger-like pseudopods.įine granules. Table 3: Differential Morphology of Protozoa Found in Stool Specimens of Humans: Amoebae-Trophozoitesġ0-60 µm. Cryptosporidium oocysts can be demonstrated in acid-fast stains.The undulating membrane of Trichomonas and the spiral groove of Chilomastix may not be visible in all cases.

Black shade in poop and pin worms