INTESTINAL SPECIES
Cyst Trophozoite Description
● Pathogenic
● Causes:
ENTAMOEBA HISTOLYTICA ○ Amebic Dysentery
○ Amebic Abscess
● Worldwide leading cause of
parasitic death
● Cysts: infected form
● Round ● Cysts or trophozoites in stool:
● 1-4 nuclei ● Rapid and directional motion diagnostic or amoebic abscess
● Central karyosome ● One nucleus with central fluid or sigmoidoscopy
● Fine and peripheral chromatin karyosome specimen
● Rounded chromatoid bar ● Ingested red blood cells (RBCs)
● Young cysts (contain glycogen are diagnostic
vacuole)
● Resistant to routine
chlorination
ENTAMOEBA COLI
● Commensal
● Cysts or trophozoites in stool:
diagnostic
● Slow motility
● Round ● One nucleus with eccentric
● 1-8 nuclei karyosome
● Eccentric karyosome ● Coarse cytoplasm
● Uneven peripheral chromatin
● Splintered end chromatoid bar
ENDOLIMAX NANA
● Sluggish, non-progressive ● Commensal
motility ● Cysts or trophozoites in stool:
● Single nucleus diagnostic
● Finely granular vacuolated
cytoplasm
● Blunt pseudopods
● Round to oval
● 1-4 nuclei with blot-like
karyosome
● NO CHROMATOID BODIES
● May have poorly defined
, glycogen mass
IODAMEOBA BUTSCHLII
● Commensal
● Cysts or trophozoites in stool:
diagnostic
● Ovoid ● Sluggishly progressive motility
● 1 nucleus ● Coarsely granular cytoplasm
● Prominent glycogen vacuole with vacuoles and bacteria
● lodine-cyst ● Blunt pseudopod
EXTRAINTESTINAL SPECIES
Cyst Trophozoite Description
● Pathogen
NAEGLERIA FOWLERI ○ Causes primary
Amoebic
Meningoencephalitis
(PAM)
● NO KNOWN CYST FORM
● Environmental organism
● Enters nasal passages →
● Trophozoites in:
bloodstream → CNS
○ CSF
● Swimming in ponds and lakes
○ Brain tissue in warm months
○ Autopsy
● 1 nucleus
● Slow motility
ACANTHAMOEBA SP. ● Pathogen
○ Causes
Granulomatous
Amebic Encephalitis
(GAE)
● Trophozoites and Cyst in:
○ CSF
○ Brain tissue
● 1 nucleus ○ Autopsy
● Double cell wall
● Slow motility ● Environmental organism
● 1 nucleus
● Enters nasal passages →
bloodstream → CNS
● Swimming in ponds and lakes
in warm months
● Eye involvement
Cyst Trophozoite Description
● Pathogenic
● Causes:
ENTAMOEBA HISTOLYTICA ○ Amebic Dysentery
○ Amebic Abscess
● Worldwide leading cause of
parasitic death
● Cysts: infected form
● Round ● Cysts or trophozoites in stool:
● 1-4 nuclei ● Rapid and directional motion diagnostic or amoebic abscess
● Central karyosome ● One nucleus with central fluid or sigmoidoscopy
● Fine and peripheral chromatin karyosome specimen
● Rounded chromatoid bar ● Ingested red blood cells (RBCs)
● Young cysts (contain glycogen are diagnostic
vacuole)
● Resistant to routine
chlorination
ENTAMOEBA COLI
● Commensal
● Cysts or trophozoites in stool:
diagnostic
● Slow motility
● Round ● One nucleus with eccentric
● 1-8 nuclei karyosome
● Eccentric karyosome ● Coarse cytoplasm
● Uneven peripheral chromatin
● Splintered end chromatoid bar
ENDOLIMAX NANA
● Sluggish, non-progressive ● Commensal
motility ● Cysts or trophozoites in stool:
● Single nucleus diagnostic
● Finely granular vacuolated
cytoplasm
● Blunt pseudopods
● Round to oval
● 1-4 nuclei with blot-like
karyosome
● NO CHROMATOID BODIES
● May have poorly defined
, glycogen mass
IODAMEOBA BUTSCHLII
● Commensal
● Cysts or trophozoites in stool:
diagnostic
● Ovoid ● Sluggishly progressive motility
● 1 nucleus ● Coarsely granular cytoplasm
● Prominent glycogen vacuole with vacuoles and bacteria
● lodine-cyst ● Blunt pseudopod
EXTRAINTESTINAL SPECIES
Cyst Trophozoite Description
● Pathogen
NAEGLERIA FOWLERI ○ Causes primary
Amoebic
Meningoencephalitis
(PAM)
● NO KNOWN CYST FORM
● Environmental organism
● Enters nasal passages →
● Trophozoites in:
bloodstream → CNS
○ CSF
● Swimming in ponds and lakes
○ Brain tissue in warm months
○ Autopsy
● 1 nucleus
● Slow motility
ACANTHAMOEBA SP. ● Pathogen
○ Causes
Granulomatous
Amebic Encephalitis
(GAE)
● Trophozoites and Cyst in:
○ CSF
○ Brain tissue
● 1 nucleus ○ Autopsy
● Double cell wall
● Slow motility ● Environmental organism
● 1 nucleus
● Enters nasal passages →
bloodstream → CNS
● Swimming in ponds and lakes
in warm months
● Eye involvement
