10 - 20 um
presence of ingested RBCs is diagnostic
Entamoeba histolytica troph
10 - 20 um
presence of ingested RBCs is diagnostic
Entamoeba histolytica troph
10 - 20 um
1 - 4 nuclei
rounded chromatoid bodies
Entamoeba histolytica cyst
5-10 micrometers
finger shaped pseudopods with nonprogressive movement
1 nuclei
peripheral chromatin is beaded
Karyosome is centrally or eccentrically located
Entamoeba hartmanni trophozoite
5-10 micrometers
1-4 nuclei
cytoplasm is finely granular
Entamoeba hartmanni cyst
5-10 micrometers
finger shaped pseudopods with nonprogressive movement
1 nuclei
peripheral chromatin is beaded
Karyosome is centrally or eccentrically located
Entamoeba hartmanni troph
5-10 micrometers
1-4 nuclei
cytoplasm is finely granular
Entamoeba hartmanni cyst
15 - 50 um
ingested bacteria
Entamoeba coli troph
10 - 35 um
1 - 8 nuclei
splinter-shaped chromatoid bodies
Entamoeba coli cyst
Entamoeba coli cyst & troph
6-12 micrometers
Large irregular “blot Like” karyosome
Absence of peripheral chromatin
Endolimax nana troph
7-10 micrometers
spherical, ovoid or elliptical
4 nuclei is most common form
no peripheral chromatin
no chromatoid bars
Endolimax nana cyst
Commensal
Found in pigs as well as in humans
Nucleus
large, irregular shape
lacks peripheral chromatin
Iodamoeba butschlii
Only ameba with 3 forms
Ameboid trophozoite
Flagellate trophozoite
Cyst
Lab Id- microscopic exam of CSF is the method of choice
tissue of nasal discharge can also be used
NO CYST STAGE IN HUMANS
Naegleria fowleri
Nucleus
large karyosome
lacks peripheral chromatin
Trophozoite
7 - 20 um
seen in purulent CSF
Naegleria fowleri
Free-living stage found in water, soil, and decaying vegetation
opportunistic parasite
enters through nasal mucosa or skin
patient usually immunocompromised
poor contact lens care
swimming in ponds while wearing lenses
Acanthamoeba species
5- 30 um
homogeneous-staining central body
occupies ~ 70% of cell
nuclear material between central body and outer membrane
No known cyst stage
Blastocystis hominis
The only ciliate known to be a human pathogen
Hogs are the true host; humans serve as accidental hosts
Most infections are asymptomatic but may cause self-limiting diarrhea
Balantidium coli
8-10 micrometers
Glycogen mass with definite borders
Iodamoeba butschlii cyst
