protozoa Flashcards
fusion of two cells or their nuclei in
reproduction
Sexual/ Syngamy:
for osmotic pressure and elimination of
waste product
Contraction vacuoles:
➢ Complete unit
➢ With specialized cells
unicellular
➢ Amitotic: single division
➢ Mitotic: repeated binary fission of nucleus
producing two daughter cells
Asexual reproduction
repeated binary fission of nucleus
producing two daughter cells
mitotic
single division
amitotic
locomotion of protozoa
organelles
inner , finely granular protoplasm primarily for
storage synthesis and digestion of food
Cytoplasm/ endoplasm
For locomotion, respiration and discharge or
metabolic wastes
ectoplasm
semi-permeable
membrane
● For intake and outtake of food
as well as for secretion or
secretory
Plasma Membrane
for regulation of osmotic pressure
contractile vacuoles
cell mouth, located laterally
at the anterior end
Cytostome-
With thin ectoplasm which is primarily for ingestion,
excretion, protection and movement
cytoplasm
cell anus
Cytophage
where flagellum arises
kinetoplast (mastigophora)
Maintenance and reproduction of life
nucleus
for nutrition and reproduction
granular voluminous endoplasm
Classification of protozoa
movement
direct; oxygen os from
enzymatic reactions
aerobic
for parasitic forms of protozoa
anerobic
opening for extrusion
nutrition; ingestion = cytopyge
types of nutrition
Absorption
ingestion
types of excretion
osmotic pressure
diffusion
precipitation
usually the infective stage
Resistant membranous wall for cervical
means of survival
reproduction
sexual union of 2 cells
syngammy
Fission through mitotic and amitotic
● May be grown in vitro
➢ Blood, serum, but it require
asexual
feeding stage/ reproducing stage/ moving stage
Trophozoite
non-feeding stage/ non-reproducing stage/ nonmoving stage
cyst
Usually resistant to adverse conditions
cyst
infective form of protozoa
CYST
invertebrae host
arthropods
- host to host without any cyclic development
direct transmisson
what development happens inside the vector and what vector did it happen into>
Cyclic development; mosquito vector
There is a vehicle (foor or water) or a vector. So when
the protozoa needs a vector, this is with a cyclic development.
indirect transmission
3 types of pathology of protozoa
Invasion
immune response
toxic products
destruction of cells
imvasion
laboratory diagnosis in cases of malaira
blood smear
diagnosis:
isolation of amoeba and flagellates
Concentration studies
amoeba superclass
Sarcodina
amoeba class
rhizopodea
THE AMOEBA UNDERGO ENCYSTATION EXCEPT FOR
ENTAMOEBA GINGIVALIS
the conversion of trophozoites into cyst form.
encystation
encystation usually occurs in?
small intestine
. The ingestion of the____ completes the
typical intestinal amebic life cycle.
infective cysts
leads to the trophozoite formation
excystation
leads to the trophozoite formation.
excystation
excystation occurs in
ileocecal of the intestines
Most pathogenic intestinal amoeba in man
Entamoeba histolytica
habitat of E.histo
large intestine, liver, lungs and brain
amoebas undergoes encystation except for?
entamoeba gingibavalis
E.histo is also known as
Amoeba Dysenteriae, Entamoeba
Dysenteriae, Entamoeba Dysentery and Entamoeba
Tetragena”
infective stage of E.histp
cyst
Chromatoidal bodies: has rounded ends giving it a
sausage shape appearance
E.histo cyts
E.histo;
❖ Ectoplasm is thick
❖ Red blood cells present
❖ No bacteria or foreign material
❖ Karyosome is centrally located
❖ Pseudopodia is fingerlike
❖ Progressive movement for the trophozoite stage of E.
histolytica
Trophozoite
E.histo:
Progressive movement for the trophozoite stage of E.
histolytica
Trophozoite
E. histo: Colorless, round or oval
❖ Smaller than trophozoite but bigger than the cyst
❖ Devoid of food inclusion
❖ Movement is sluggish
Precystic
optimum temp and pH of E.histo cyst
37 deg cel; pH 7
chromatoidal bodies has rounded eggs giving it a sausage shape appearance
E.histlytica
thermal death point of E.histo cyst
50 deg cel
resistant to urine
E. histo cyts
how many nuclei in mature and immature cyst if E.histo
4 in mature
1-2 in immature
movement of E.histo
Active
Progressice
DIrectional
Fingerlike
Disease E.histo;
There are symptoms that are apparent
Luminal amoebiasis
● the trophozoites would invade
the intestinal mucosa to produce dysentery or
ameboma that can spread in
the blood to give extra
intestinal lesions like liver
abscess.
Invasive amoebiasis
asymptomatic infection
Luminal amoebiasis specifically the E.dispar
this is useful in
differentiating Entamoeba histolytica from Entamoeba
dispar because these two are morphologically
indistinguishable.
Polymerase chain Reaction
Not useful for demonstrating trophozoites
Fecalysis; E.histo
Fresh stool: wet mounts (with or without the iodine stain)
and permanently stained preparations
Fecalysis; e histo
. It can also help in the differentiation of
luminal infection caused by Entamoeba dispar from
invasive amoebiasis caused by Entamoeba histolytica.
Polymerase Chain Reaction
most useful in patient with
extraintestinal disease (i.e. amebic liver abscess) when
organisms are not generally found on stool examination
antibody detection
: useful as an adjunct to microscopic
diagnosis in detecting parasites and to distinguish between
pathogenic and non-pathogenic infections (between E.
histolytica and E. dispar infections
Antigen detection
Habitat of Entamoeba hartmanni
intestinal tract of man
the size of E.hart resembles?
Endolimax nana
nucleus resembles E.coli
E.hart
chromatoidal bar of E.hart is shaped?
Rice Grain Shape or thin fan like
- Trophozoite doesn’t ingest RBCs
- Utility is less vigorous
- Chromatoidal bodies are shorter with tapered ends giving a
rice grain shape or thin fan like appearance - Non-pathogenic; causes only mild symptoms of enteritis
Entamoeba hartmanni
habitat of E.coli
Large intestine of Human
Trophozoite
○ -nucleus is not easily visualized
○ -karyosome is eccentric
○ -Movement is sluggish
○ -Pseudopod is broad and short
○ -granular ectoplasm is not easily differentiated from the
endoplasm
ENTAMOEBA COLi
○ -chromatoidal bodies are splinter like filamentous giving
a whisk broom appearance
○ 1-8 nuclei
○ Transmission: hand to mouth
○ Diagnosis: cyst and trophozoite in fecal sample
○ Prevention:
1. Personal hygiene
2. Sanitary disposal of wastes
Cyst of E.coil
diagnosis if E.coli cyst
cyst and trophozoite in fecal sample
how many nuclei in e/coli
1-8
E.coli:
chromatoidal bodies are splinter like filamentous giving
a whisk broom appearance
cyst of E.coli
Transmission of cyts of E.coli
Hand to mouth
Diagnosis of E.coli
Cyst and trophozoite in fecal sample
E. histo or E.coli?
Finger like pseudopodia
E.histo
E.histo of E.coli?
Blund and broader pseudopodia
E.coli
E.histo of E.coli?
Eccentric karyosome
E.coli
E.histo of E.coli?
Progressive and
directional motility
E.histo
E.histo of E.coli?
Sluggish, nonprogressive, nondirectional
E.coli
E.histo of E.coli?
Bull’s eye nucleus
E.histo
E.histo of E.coli?
nuclear membrane is thin
E.histo
E.histo of E.coli?
Dirty-looking, heavily
vacuolated due to
ingested bacteria and
food particles
E.coli
E.histo of E.coli?
Clean-looking, with
ingested RBCs
E.histo
E.histo of E.coli?
Small race
(nonpathogenic)
Large race
(pathogenic)
E,histo
E.histo of E.coli?
nuclear membrane is thick
E.coli
E.histo of E.coli?
1-4 nuclei (infective)
E.histo
E.histo of E.coli?
Sausage shaped chromatoidal bodies
e.histo
E.histo of E.coli?
Splinter/broomstick appearance chromatoidal bodies
E.coli
E.histo of E.coli?
1-8 nuclei
E.coli
smalles intestinal protozoan of man
Endolimax nana
synoynm of E.nana
Cross-eyed cyst
Entamoeba nana
Endolimax intestinalis
Trophozoite:
o 2-12 um
o Uninucleated
o Finely granular, vacuolated cytoplasm (with narrow rim
of ectoplasm)
o Short pseudopod
o Movement is sluggish
o Karyosome: central or eccentric
ENDOLIMAX NANA
Cyst:
o 5-10 um
o Round to oval; usually oval
o 1-4 nucleus; possesses 4 nuclei when mature
o Chromatoidal bodies are comma-shaped
ENDOLIMAX NANA
Chromatoidal bodies are comma-shape
cyst of E.nana
habitat of I.buts
Large intestine of man and swine
non-pathogenic amoeba
IODAMOEBA BUTSCHLII
Common name of I.buts
Iodine Cyst
Synonym of I.buts
Iodamoeba williamsi, Entamoeba williamsi, Entamoeba
butschlii, Endolimax williamsi,
similar to Entamoeba Histolytica but note that it is noninvasive
I.buts
Trophozoite
o 8-20 um
o Coarsely granular cytoplasm with vacuoles and bacteria
o Blunt pseudopods (sluggishlyprogressively motility)
o Small with fairly active, progressive movement
o Ectoplasm is clear
o 1 spherical nucleus
o Karyosome is central and eccentric
I.buts
o 5-20 um
o Ovoid
o Only one nucleus when mature
o Prominent glycogen vacuole (iodine-staining)- dark
brown
o Large glycogen vacuole
Cyst of I.buts
Coarsely granular cytoplasm with vacuoles and bacteria
Trophozoite of I.buts
Blunt pseudopods (sluggishlyprogressively motility)
Trophozoite of I.buts
1 spherical nucleus
Trophozoite of I.buts
only one nucles when mature
cyst of I.buts
Prominent glycogen vacuole (iodine-staining)- dark
brown
Cyst of I.buts
large glycogen vacuole
Cyst of I.buts
Made by finding the characteristics cyst in an iodine stain or
in a formol, ether concentration
I.buts
The trophozoites are difficult to detect in a wet preparation
I.buts
Found in the mouth, chiefly in the tartar of the teeth and
gingival pocket
ENTAMOEBA GINGIVALIS
Humans are the only host, however occasionally the parasite
has also reported in the mouth of dogs and cats
E.gingi
Been claimed that it contributes to periodontal disease
E.gingi
first amoeba of
human
E.gingi
E.gingi is discovered by?
Discovered by Gros, in 1849
MOT of e.gingi
Kissing or droplet spray
Contaminated drinking utensils and dental utensils
no specific drug or medicine that is prescribe to kill the
microorganism, what is recommended is prophylaxis or
prevention through proper hygiene
ENTAMOEBA GINGIVALIS
Cytoplasm: WBC, epithelial cells, bacteria, and food
vacuoles
E.gingi
Extrudes pseudopodia, similar to E. histolytica but does
not exhibit progressive locomotion
E.gingi trophozoite
Multiple pseudopodia
Trophozoite of E. gingi
The presence of ingested leukocytes and their nuclear
fragment cyst diagnostic as no other amoeba ingest risk
cells
Trophozoite of E. gingi
Nucleus is round with peripheral chromatin & large
central karyosome
o Cytoplasm: WBC, epithelial cells, bacteria, and food
vacuoles
Trophozoite of E. gingi
a commensal and is not considered
to cause any disease
Entamoeba gingivalis
Found in bronchial washings from cases of pulmonary
suppurations and in sputum where it can be mistaken for
Entamoeba histolytica from lung abscess
Entamoeba gingivalis
Originally described as amoeba, but is actually a flagellate
with only the trophozoite stage known.
DIENTAMOEBA FRAGILIS
it is now classified among the trichomodas
D. fragilis
○ Binucleated trophozoite
○ Absence of the cyst stage
○ Electron microscopic evidence of rudiments
○ Resembles Trichomonads antigenically and
ultrastructurally
DIENTAMOEBA FRAGILIS
is D. fragilis pathogenic or non pathogenic?
pathogenic
habitat of D.fragilis
Mucosal crypts of the cecum
Resembles Trichomonads antigenically and
ultrastructurally
DIENTAMOEBA FRAGILIS
Usually in co-infection with E. vermicularis
D.fragilis
○ Binucleated trophozoite
D.fragilis
Absence of the cyst stage
D.fragilis
Electron microscopic evidence of rudiments
D.fragilis
Resembles Trichomonads antigenically and
ultrastructurally
D.fragilis
Could be recognized only in fresh liquid or soft stool specimen
D.fragilis
Prompt fixation with PVA or Schaudinn’s is helpful
D.fragilis
has 2 nuclei
D.fragilis
Circular appearance at rest
D.fragilis
multiple leaf shaped pseudopods
D.fragilis
Rapid action of the multiple leaf-shaped
pseudopods that gives a stellate appearance, and
explosive disintegration in water
D.fragilis
– are facultative parasites of
man.
Acanthamoeba and Naegleria
habitat of acanthamoeba and naegleria
Stagnant water, brackish and ocean sediments,
thermal pools, swimming pools, polluted soil, sewage disposal
systems
once it enters the human host, acanthamoeba and naegleria inhabits what
central nervous system
Trophozoite can assume limax form or become
ameboflagellate
N.fowleri
Has both amoeba and flagellated form
N.fowleri
Ameboid: has a blunt pseudopodia and a vesicular
nucleus with a large karyosome and sparse
granules of peripheral chromati
N.fowleri
Only amoeboid trophozoite inside the
host
N.fowleri
Flagellated: elongated and bears two equal and
anteriorly located flagella
N.fowleri
Cyst wall is smooth and double, with the outer wall
perforated by 3 – 8 pores (ostioles)
N.fowleri
3-8 pores of N.fowleri is called
Ostioles
Survive up to 46 degrees celsius
○ Survive at 0.5ug/mL chlorinated water
N.fowleri
Major causative agent of Primary Amebic
Meningoencephalitis (PAM)
N.fowleri
On autopsy examination (of mice and animals), the normal
architecture of the brain, particularly the olfactory lobes and
cerebral cortex is completely destroyed. (“Brain-eating
amoeba”)
N.fowleri
Causes purulent spinal fluid with motile amoeba
N.fowleri
Stained smears of culture material (demonstration of the
trophozoites in CSF)
○ Trophozoite in brain and CSF
N.fowleri
Swimming in contaminated water
● Using inadequately disinfected contact lenses
Acanthamoeba
PORTAL OF ENTRY:
● broken or ulcerated skin or eye, lungs, genitourinary tract
(GUT)
Acanthamoeba
Uninucleated and double walled
cyst of acanthamoeba
____has two stages; cysts image and trophozoites
image in its life cycle and lacks a flagellate stage.
Acanthamoeba
When__enters the eye it can cause severe
keratitis in healthy individuals, particularly contact lens users
Acanthamoeba spp.
Both Acanthamoeba spp. cysts and trophozoites are found in the
____
tissue
Ulcerative Acanthemoeba Keratitis in contact lens wearers
acanthamoeba
Granulomatous Amebic Encephalitis (GAE)
○ Lesions in the brain
○ Chronic central nervous system infection;
generally, in debilitated or immunocompromised
patients
Acanthamoeba
Chronic Granulomatous lesions in the brain, skin, kidneys,
liver, spleen, uterus, and prostate
Acanthamoeba
Microabscesses in the lungs and pancreas
Acanthamoeba
- Cerebrospinal fluid
- Nasal swabs
- PYGC medium containing antibiotics (culture medium)
● Stained smears of culture material
● Histologic examination of brain
● Trophozoites and cysts in corneal scrapings
Acanthamoeba
● Amphotericin B (given intravenously)
● 5-fluorocytosine, pentamidine
● Ketoconazole
● Itraconazole
Acanthamoeba
