Martin Flashcards
1
Q
Classicfications of Parasites:
A
- Protozoa:
- Subgroups
- Amoeba
- Flagellates
- Sporozoa
- Ciliates
- Subgroups
- Stamenopila
- Blastocystis spp
- Helminths (or worms
- subdivided into:
- Nematodes (round worms)
- intestinal, blood and tissue nematodes
- Trematodes (flatworms)
- aka flukes
- intestinal, blood, tissue
- Cestodes
- tapeworms
- intestinal and tissue cestodes
- Nematodes (round worms)
- subdivided into:
2
Q
Trophozoite
A
- Active protozoal parasite
- Feeding stage
3
Q
Cyst
A
- Infectious form of protozoan parasite
- cell wall
- condensed
4
Q
Cilia
A
- small hair-like processes on cell surface
- composed of (9x2)
- 9 pairs of microtubules around a core of 2. microtubules
- Cell movement
5
Q
Definitive Host
A
- Final host in sexual/adult life cycle
6
Q
Intermediate host
A
- Host in which parasite passes its larval or nonsexual
7
Q
What are the Different types of Parasites:
-pathogenic species
A
- Amebae
- Flagellates
- Ciliates
- Sporozoa
8
Q
Protozoa: Amoeba
A
- Enteric pathogen
- pathogenic: Entamoeba Hystolytica
- Diarrhea
- local tissue dmage
- liver abcesses (less frequent)
- Nonpathogenic- asymptomatic
- E. dispar
- E. hartmanni
- E. coli
- pathogenic: Entamoeba Hystolytica
- Fecal oral route
- Unicellular organisms
- asymmetric morphology
- Motility:
- pseudopod extension and retraction
- Trophozoites
- active replicating stage
- nuclear morphology and cytosol appearnce used for ID in fecal smear
- Cysts
- infective stage
- dormant stable
- nuclei number and morphology used for ID
- Reproduction:
- Binary cell division
- mitosis
- Binary cell division
- Colonize GI tract
- Detection:
- Stool specimen:
- all amebae
- presence of cyst or trophozoite
- Enzyme Immunoassays (EIAs)
- detect antigens
- only E. histolytica
- Stool specimen:
9
Q
Entamoeba Hystolytica: Pathogenesis
A
- 10-20% become sick
- Mild symptoms:
- loose feces
- stomach pain
- stomach cramping
- Amebic dysentery
- severe infection
- invades the wall of large intestine
- Stomach pain
- bloody stools
- fever
- Rarely invades the liver and forms abscess
- Can spread to lungs or brain
- uncommon
- Prevention:
- adequate water treatment
- clean fruits and vegetables before consumption
10
Q
Protozoa: Mucosal Flagellates
A
- Unicellar organisms
- Motile:
- Flagella
- Replicate:
- binary cell division (Mitosis)
- 3 species:
- G. Lamblia
- form cysts
- GI parasite
- fecal oral route
- D. fragilis
- form cysts
- Gi Parasite
- Fecal oral route
- T. vaginalis
- no cysts
- Urogenital Parasite
- sexual contact
- G. Lamblia
- Diagnostic:
- cell morphology
- flagella number and location
- cyst formation
11
Q
G. Lamblia
A
Mucosal Flagellates
- Form Cysts
- Gi Parasite
- fecal-oral route
- Trophozoites
- pear shaped
- concave “sucking disk”-adhere to GI tract
- 2 curved rods below the nuclei
- 8 flagella
- Cysts:
- ovoid
- 4 nuclei
- central fibrils
- Acute Sympotoms:
- Diarrhea
- gas
- Greasy stools that float
- stomach crmaps
- Upset stomach or N & V
- Dehydration
- Reservoir:
- asymptomatic=carrier
12
Q
T. Vaginalis
A
Mucosal Flagellates
- No Cysts
- Urogenital parasite
- sexual contact
- Trophozoite Only (no cysts)
- pyriform
- nucleus contains chromatin granules and small karyosome
- Undulating membrane
- extends half-way down parasite
- Flagella
- extend from anterio of parasite
- Diagnostic:
- Jerky MOtion
- highly motile
- Jerky MOtion
- UTI
- In men:
- itching/irritation
- Burning after urinatin
- Discharge
- Women:
- itching, burning, redness, or soreness of genitals
- Discomfort with urination
- change in vaginal discharge
- thin discharge or increased volume
- clear, white, yellow, green
- fish smell
- In men:
- Unpleasant sex
- without treatment:
- can last months to years
13
Q
D. Fragilis
A
Mucosal Flagellates
- Form Cysts
- GI parastie
- fecal oral contamination
14
Q
Protozoa: Intestinal Ciliates
A
- Balantidium coli
- only ciliate human pathogen
- GI parasite
- fecal oral route
- asymptomatic (mostly)
- pts with other serious illness can have:
- persistent diarrhea
- abdominal apin
- perforated colon
- pts with other serious illness can have:
- rare in US
- trophozoites
- unicellular
- cilia
- Cysts
- infectious form
- Symptoms: (amebiasis like)
- Abdominal pain
- Nausea
- diarrhea
- May cause tissue damage and intestinal ulceration in large intestine
- Reservoir
- Swine
- monkeys (less common)
- Swine
- Diagnosis:
- stool sample
- presence of trophozoites and cysts
- stool sample
- Prevention: Endemic tropical countries
- good hyigene
- wash all fruits and vegetables
15
Q
Protozoa: Intestinal Sporozoa
A
Cryptosporidium spp.
- spread via:
- water systems
- fecal oral route
- Self-limiting disease (<10 days)
- AIDs patients:
- diarrhea (50 days)
- disseminated infections
- Normal Symptoms:
- severe watery diarrhea
- dehydration
- weightloss
- low grade fever
- abdominal cramp
- fatigue
- N & V
- epigatric or Right upper quadrant tenderness
- severe watery diarrhea
- Diagnossi:
- fecal samples
- Acid fast stain
- oocysts
- fecal samples
