Protozoans Flashcards
MOT and habitat or E. histolytica
MOT: ingestion of infective cyst
Habitat: Large intestine
The only pathogenic amoeba
E. histolytica
Number of nucleus of E. histolytica
Cyst: 4
Troph: 1
Described as clean-looking cytoplasm
E. histolytica trophozoite
Distribution of peripheral chromatin in E. histolytica
Evenly distributed
The only hematophagus amoeba
E. histolytica trophozoite
Appearance of chromatoidal bar of E. histolytica
cigar/sausage-shaped
Motility of E. histolytica trophozoite
Unidirectional, progressive
E. histolytica look-alikes
E. dispar
E. moshkovskii
E. bangladeshi
Virulence factor of E. histolytica
GalNac Lectin (for attachment), amoebapores (for holes), cysteine proteinases (for tissue disruption)
Used for differentiation of E. histolytica and E. dispar
ELISA
Drug of choice for E. histolytica for symptomatic px
Metronidazole
Drug of choice for E. histolytica for asymptomatic px
Diloxanide Furoate
Alternative drug for E. histolytica
Iodoquinol
Incubation period of E. histolytica
1-4 weeks
What are the commensal amebae?
E. coli, E. hartmanni, E. polecki, E. chattonii, E. nana, I. butschlii, E. gingivalis
Described as dirty-looking cytoplasm
E. coli troph
Appearance of chromatoidal bar of E. coli cyst
Splinter/broom stick shape
Motility of E. coli troph
Non-directional, non-progressive
Number of nuclei of E. coli
Cyst: 8
Troph: 1
Small race of E. histolytica
E. hartmanni
Number of nuclei of E. hartmanni
Cyst: 1-2
Troph: 1
Motility of E. hartmanni
Sluggish, non-progressive
Amoeba of pigs and monkeys
E. polecki
Number of nuclei of E. polecki
Cyst & Troph: 1
E. polecki is the most common parasite in ____
Papua New Guinea
Motility of E. polecki
Unidirectional, progressive, sluggish
Seen in apes and monkeys
E. chattoni
E. chattoni is morphologically similar to _____
E. polecki
Smallest intestinal amebae
E. nana
Number of nuclei of E. nana
Cyst: 4
Troph: 1
Has cross-eyed karyosome
E. nana
Appearance of chromatin in E. nana trophozoite
blunt and hyaline pseudopodia
Motility of E. nana troph
Unidirectional, non-progressive, sluggish
movement
Has a “basket of flowers” appearance
I. butschlii
Additional structure of I. butschlii
Glycogen vacuole
Amoeba that has no cyst stage
E. gingivalis
Also found in tartar, gingival pockets of teeth, and tonsillar crypts (of unhealthy mouths, but may also be in healthy mouths)
E. gingivalis
First amoeba in man
E. gingivalis
E. gingivalis is non-pathogenic, but can be seen in patients with _____
Pyorrhea alveolaris (gum infections)
The infective stage of free-living pathogenic amebae
Trophozoite
Found in inhabiting lakes, pools, tap water, air conditioning units, and heating units
Free-living pathogenic amebae
Target of free-living pathogenic amebae
CNS; brain tissue and CSF can be examined
Only Naegleria species that can infect humans
Naegleria fowleri
What does thermophilic mean?
thrive best in hot springs and other warm aquatic environments
Forms of N. fowleri
Cyst: spherical and single-walled
Troph: 1 nucleus, large & dense karyosome, cytoplasm is granular
Amoeboid form: limax-form (slug-like)
Ameboflagellate: 2 anterior flagella