Para Lab 9

PARASITOLOGY LABORATORY 9 – Protozoans USTMED ’07 Sec C – AsM; Photos provided by JV.N.

ENTAMOEBA HISTOLYTICA E. Histolytica Cyst

ENTAMOEBA COLI Mature cysts of E. histolytica have four nuclei while immature cysts contain one or two nuclei. The cysts range in size from 10 to 18 um and frequently have a diffuse glycogen vacuole, as in this case. Red chromatoid bodies with rounded ends are frequently found. The karyosomes may be slightly eccentrically located, and the peripheral chromatin is fine and evenly distributed.

E. coli – Iodine Stained

E. Histolytica Trophozoites

E.coli trophozoite with nucleus in which the karyosome appears large and irregular

E. coli trophozoite with nuclei in which the karyosome is eccentric, cytoplasm is vacuolated Entamoeba histolytica.

Trophozoites. Feces. Trichrome stain. The trophozoites of E. histolytica are round and measure from 15 to 30 um in diameter. With the trichrome stain the cytoplasm stains green-magenta, and the nucleus has a central karyosome. The chromatin has a delicate appearance and is distributed uniformly in the periphery along the nuclear membrane.

Entamoeba histolytica cyst

Entamoeba histolytica.

ENTAMOEBA HARMANII Entamoeba harmanii

Trophozoites. Feces. Trichrome stain. This E. histolytica trophozoite shows an ingested red blood cell in the cytoplasm. The nuclear structure is still fairly typical although the karyosome is eccentrically located. Ingestion of red blood cells by E. histolytica occurs in patients with invasive disease and is considered to be a characteristic that distinguishes this organism from the other species of Entamoeba. In addition to red cells, bacteria and cell debris can be found in the phagosomes of this parasite. Macrophages that have ingested cellular material can sometimes be confused with E. histolytica.

Typical E. harmanii trophozoites are small, and characteristically take a light stain. The nucleus is small, has a discrete central karyosome, and fine peripheral chromatin. The cytoplasm, which usually is finely granular, never contains red blood cells. ENDOLIMAX NANA Endolimax nana cyst

Amoebiasis Intestine

IODAMOEBA BUTSCHLII Iodamoeba Butschlii Trophozoites

Trichrome-stained trophozoites demonstrates characteristic vacuolations of the cytoplasm and the typical nucleus containing large, dark staining karyosome. Nuclear membrane lacks peripheralchromatin.

Iodamoeba butschlii cyst

The most characteristic feature of Iodamoeba cysts is its large glycogen vacuole clearly seen in this trichrome-stained organism. The cyst are invariably uninucleate and has a typical large karyosome.

Iodamoeba butschlii

Iodameoba butschlii Trophozoites Cysts

[email protected] [email protected]