U4.2 - Protozoans (Flagellates) Flashcards
1
Q
protozoans characterized by the presence of whip- like locomotory organ
A
flagellates
2
Q
structure that enables locomotion
A
flagella
3
Q
Flagellates:
Before: Phylum ______________
Now: Phylum ______________
A
Sarcomastigophora
Metamonada
4
Q
3 pathogenic flagellates
A
- Giardia lamblia
- Dientamoeba fragilis
- Trichomonas vaginalis
5
Q
Flagellates with no cyst stage
A
- Trichomonas vaginalis
- Trichomonas hominis
6
Q
All flagellates undergo encystation except?
A
Trichomonas species
Dientamoeba fragilis
7
Q
Flagella is attached to the ____________ found on the body of the parasite.
A
blepharoplast
8
Q
All flagellates undergo asexual reproduction through?
A
binary fission
9
Q
T/F:
Dientamoeba fragilis has no cyst stage.
A
False;
before: no cyst stage
now: has a cyst stage
10
Q
characterized by foul-smelling diarrhea with increased amount of fat and mucus but no blood
A
Giardia duodenalis
11
Q
Where can Giardia duodenalis be found?
A
Found on surfaces or in soil, food, or water that has been contaminated with feces (poop) from infected humans or animals
12
Q
Giardia duodenalis:
hosts
A
Humans and other mammals, birds and reptiles
13
Q
Giardia duodenalis:
type of infection
A
zoonotic
14
Q
other terms for Giardia duodenalis
A
- Giardia lamblia
- Giardia intestinalis
15
Q
T/F:
Giardia duodenalis accounts for STDs
A
True;
through anal sex
16
Q
Giardia duodenalis:
habitat
A
duodenum (crypts)
17
Q
Giardia duodenalis:
MOT
A
ingestion of infective cysts from fecally contaminated water or food
18
Q
structure targeted by Giardia duodenalis
A
brush borders of intestinal epithelia
19
Q
Explain why stool with Giardia duodenalis has excess mucus or fat.
A
The brush borders of intestinal epithelia responsible for absorption are targeted by G. duodenalis, so lipids are not absorbed, causing foul smell upon stool passage.
20
Q
Giardia lamblia was coined by?
A
Giard and Lambl
(in 1800s)
21
Q
also discovered Giardia lamblia in his own stool
A
Antonie van Leeuwenhoek
22
Q
Giardia duodenalis:
virulence factor
A
ventral sucking disc
23
Q
Unique structure of Giardia duodenalis that attaches to the intestinal cells
A
ventral sucking disc
24
Q
Once the G. duodenalis is attached to the intestinal cells, the parasite cause what?
A
- villous flattening
- crypt atrophy
25
G. duodenalis trophozoites adhering to GIT target signaling networks such as caspases that initiate cellular apoptosis leading to?
1. loss of intercellular junctions
2. cytoskeleton rearrangement
3. cell barrier dysfunction
26
Giardia duodenalis:
pathophysiological mechanisms
1. diarrhea
2. malabsorption
3. electrolyte imbalance
27
Giardia duodenalis (trophozoite)
motility:
shape:
nuclei:
flagella:
motility: falling leaf
shape: inverted, pear, spoon, teardrop
nuclei: 2
flagella: 4 pairs (2 lateral, 1 ventral, 1 caudal)
28
Giardia duodenalis:
additional structures
1. claw-hammer-shaped median bodies
2. ventral sucking disk
3. 2 axostyles
29
Giardia duodenalis is made up of?
cytoskeleton/ microtubules
30
Giardia duodenalis:
appearance
old man's eye with glasses
31
Giardia duodenalis:
median bodies function
energy source
32
Giardia duodenalis:
axostyle and axoneme function
support and movement
33
Giardia duodenalis (cyst)
motility:
shape:
nuclei:
flagella:
size:
Giardia duodenalis (cyst)
motility: nonmotile
shape: oval, ellipsoidal
nuclei: 4 in mature (2-4)
flagella: none
size: 8-19 um x 11-14 um (LW)
34
Giardia duodenalis (cyst):
additional structures
1. median bodies
2. axoneme (multiple axostyles)
3. deeply stained, curved fibrils
35
Giardia duodenalis:
pathology
1. Similar to amebiasis and bacterial diarrhea
2. Traveler’s diarrhea, gay bowel syndrome
3. Epigastric pain, flatulence, fat malabsorption
36
Giardia duodenalis:
diagnosis
1. routine stool examination
2. entero test
3. duodenal aspirate examination
4. immunoassyas
5. tissue biopsy
6. molecular testing
37
entero test is also called
string test
38
identify the parasite where entero test is performed
G. duodenalis
39
Giardia duodenalis:
prevention and control
1. proper or sanitary disposal of human excreta
2. normal water chlorination will not affect cysts, but usual water treatment modalities should be adequate.
- purification methodologies (boiling of water)
40
originally described as ameba
Dientamoeba fragilis
41
Dientamoeba fragilis (trophozoite and cyst):
nuclei:
peripheral chromatin:
karyosome:
nuclei: 1 or 2
peripheral chromatin: nuclear membrane has no chromatin
karyosome: 4-6 discrete granules
42
Dientamoeba fragilis (trophozoite):
motility:
resemblance:
flagella:
size range:
motility: nonprogressive (with pseudopod)
resemblance: amoeba
flagella: no visible flagella (under EM: alike flagella of trichomonads)
size range: 5-15 um
43
Dientamoeba fragilis (cyst):
motility:
cell wall:
size range:
motility: nonmotile
cell wall: inner and outer
size range: 5-8 um
44
The genes of D. fragilis are very common among?
Trichomonas
45
Dientamoeba fragilis:
MOT
fecal-oral route
46
Dientamoeba fragilis may be carried by?
1. Ascaris eggs
2. Enterobius eggs
47
T/F:
Trophozoites cannot survive mucus induced by D. fragilis.
False;
can survive
48
Dientamoeba fragilis:
pathogenesis
1. usually asymptomatic
2. common symptoms: intermittent diarrhea with excess mucus
49
T/F:
Dientamoeba fragilis diagnosis:
Perform DFS.
True
50
T/F:
Dientamoeba fragilis diagnosis:
detected by concentration techniques
False;
cannot be detected
51
Dientamoeba fragilis diagnosis:
fixatives used
1. PVA fixative
2. Schaudinn's fixative
52
Dientamoeba fragilis:
treatment
Iodoquinol
53
Trichomonas vaginalis exists as?
1. pseudocystic stages - round, no motility
2. trophozoites
- flagellate and ameboid (pear-shaped)
NO CYST STAGE
54
rapidly dividing tissue-feeding forms of trophozoites
ameboid
55
Trichomonas vaginalis:
motility:
shape:
flagella:
size:
motility: non-directional/ jerk
shape: pear-shaped/ pyriform
flagella: 3-5 anterior, 1 posterior
size: 7-23 um x 5-15 um
56
Trichomonas vaginalis:
additional structures
undulating membrane
57
Trichomonas vaginalis:
MOT
1. sexual transmission
2. infant delivery
3. use of contaminated towels and underwear
58
Trichomonas vaginalis:
habitat
female: vagina/ cervix
male: prostate gland
59
Trichomonas vaginalis:
found usually in ________ specimen
vaginal / urethral
urine
60
Trichomonas vaginalis:
reproduction
binary fission
61
Trichomonas vaginalis:
virulence factor
release of lytic enzyme
62
Trichomonas vaginalis:
likes acidic or basic pH?
acidic
63
What does T. vaginalis do to the tissue?
small puncture in the tissue
causes hemorrhagic spots inflaming cervix, vaginal wall, and prostate
64
Trichomonas vaginalis releases this enzyme; what is its capacity?
proteinases
lysis capacity (lyse RBCs and surrounding tissue)
65
Trichomonas vaginalis:
pathology
female (symptomatic):
1. Leukorrhea
2. vulvovaginatis
3. intense burning and itching sensation (pruritus vulva)
4. strawberry cervix
male (asymptomatic):
1. UTI
2. inflamed seminal vesicle, prostate, or epididymis
66
Trichomonas vaginalis:
virulence capabilities
1. cysteine proteinases
2. nutrient acquisition and adherence
3. cell-detaching factor = cytopathic effect
4. damage of target plasma membrane
5. interaction with vaginal flora
6. immune system evasion
7. virulence genes regulation
67
Trichomonas vaginalis:
thrives in _________ flora
pH: ______
acidic
4.5
68
Trichomonas vaginalis:
diagnosis
1. urinalysis
2. vaginal discharge, vaginal scrapings examination
3. cervical smear
4. seminal, prostatic fluid examination
5. fluorescent staining
6. culture
7. immunoassays
8. molecular testing
69
Trichomonas vaginalis:
treatment
1. metronidazole
2. antibiotic - bacterial disinfection
70
patients affected by T. vaginalis
HIV/ AIDS patients
71
T/F:
The cyst morphologic form is not known to exist in the life cycle of T. vaginalis.
True
72
T. Vaginalis may be recovered in which of the following specimens?
A. Urine
B. Vaginal discharge
C. Blood
D. Urethral discharge
E. More than one: specify ____
A
B
D
73
Non-pathogenic Flagellates
1. Pentatrichomonas (Trichomonas) hominis
2. Trichomonas tenax
3. Chilomastix mesnili
74
Chilomastix mesnili (trophozoite)
motility:
nuclei:
flagella:
size:
motility: boring, rotary, cork screw, spiral forward
nuclei: 1
flagella: 3 anterior, 1 in cytostome
size: 10-20 x 3-10 um
75
shepherd's crook-like cytostome/ spiral groove of the cystomal fibril
Chilomastix mesnili (trophozoite)
76
safety pin appearance
Chilomastix mesnili (trophozoite)
77
Chilomastix mesnili (trophozoite):
additional structures
1. cystomal fibril (shepherd's crook-like cytostome/ spiral groove)
2. spiral groove across ventral surface
78
Chilomastix mesnili (cyst)
motility:
shape:
nuclei:
size:
motility: nonmotile
shape: lemon-shaped/ nipple-shaped
nuclei: 1
size: 6-10 um
79
Chilomastix mesnili (cyst):
additional structures
anterior hyaline knob
80
Identify the parasite:
Almost the same life cycle as Chilomastix
Enteromonas hominis
81
Enteromonas hominis:
MOT
ingestion of cysts
(Contamination of water, food, or hands/fomites with infective cysts)
82
Enteromonas hominis (trophozoite):
nucleus:
shape:
flagella:
motility:
nucleus: 1
shape: oval
flagella: 3 anterior, 1 posterior
motility: jerky motility
83
Enteromonas hominis (cyst):
nucleus:
shape:
motility:
Enteromonas hominis (cyst):
nucleus: 2 or 4 (located at ends of cyst)
shape: oval
motility: nonmotile
84
Identify the parasite:
Almost the same life cycle as E. hominis
Retortamonas intestinalis
85
Retortamonas intestinalis (trophozoite):
nucleus:
flagella:
cytostome:
motility:
nucleus: 1
flagella: 1 anterior, 1 posterior
cytostome: cleft-like
motility: jerky motility
86
Retortamonas intestinalis (cyst):
nucleus:
shape:
cytostomal fibril:
motility:
nucleus: 1
shape: pear-shaped or slightly
lemon-shaped
cytostomal fibril: bird’s beak
appearance
motility: nonmotile
87
Identify the parasite:
Formerly known as Trichomonas hominis
Pentatrichomonas hominis
88
Pentatrichomonas hominis:
number of flagella
5 (penta)
89
Pentatrichomonas hominis:
habitat
colon
90
Pentatrichomonas hominis (trophozoite):
nucleus:
motility:
flagella:
additional structures:
nucleus: 1
motility: jerky motility
flagella: 4 anerior, 1 posterior
additional structures:
1. Conical cytostome
2. Axostyle
3. Undulating membrane
91
T/F:
Pentatrichomonas hominis (trophozoite) has a peripheral chromatin.
False
92
Trichomonas tenax:
habitat
mouth
1. tartar of teeth
2. cavities of carious teeth
3. necrotic mucosal cells in gingival margins
93
Trichomonas tenax:
MOT
1. direct contact (kissing)
2. use of contaminated glass or dishes (sharing of utensils)
94
Identify the parasite:
Smallest among the flagellates
Trichomonas tenax
95
Identify the parasite:
Resistant to changes in temperature
Trichomonas tenax
96
Identify the parasite:
Will survive for several hours in drinking water
Trichomonas tenax
97
Trichomonas tenax (trophozoite):
nucleus:
shape:
flagella:
motility:
nucleus: 1
shape: pyriform
flagella: 4 anterior, 1 posterior
motility: jerky motility
98
Trichomonas tenax (trophozoite):
additional structures
1. Axostyle
2. Cytostome
3. Undulating membrane
- 2/3 body length
