Test 5 Protozoa Flashcards
What is the Metabolic stage with active, vegetative, feeding, and is capable of movement?
Trophozoite
What is the shape of a Trophozoite?
Varied, mostly subspherical.
-DEPENDENT upon cytoplasmic structure and organelles
What parasite is capable of invading tissue and causes intestinal amebiasis and Extra-intestinal amebiasis?
Entamoeba histolytica
Disease characteristics of Intestinal Amebiasis that Entamoeba histolytica causes are?
- Non-dysenteric colitis
- Amebic dysentery
Disease characteristics of Extra-intestinal amebiasis that Entamoeba Histolytica causes?
- Hepatic: Most Frequent, Right lobe of Live
- Pulmonary
- Brain: CNS
- Other Organs: e.g. Spleen, kidneys, etc..
Which parasite’s pathogenicity consist of incidence being higher in children and young adults w/symptoms of irritation to intestinal mucosa and recurrent diarrhea (dehydration)? What disease is caused by it?
Giardia lamblia
Disease: Giardiasis
What is the only pathogenic ciliate?
Balantidium Coli
In the protozoan nuclei what is lacking in the compact type?
Clear Nucleoplasmic zones as found in ciliates
Protozoan Nuclei typically consist of two a Macronucleus and Micronucleus, describe each.
- Macronucleus: Large; associated w/cell trophic activities
- Micronucleus: Small, often obscure; associated w/reproductive activities
What is the Organ of locomotion for Protozoa?
Flagella: Long hair-like structures; characteristic of mastigophorans
What is significant of the flagella of Protozoa?
- Organisms often describe by number/arrangement
- Facilitates propelling and procurement of food (some)
What parasite uses tissue lysing enzymes that create ulcerations/penetrations of the mucosal crypts and these extensions into submucosa form a flask-shaped lesion?
Entamoeba histolytica
What common life stage is associated w/ transmission to a new host and is entered into just prior to passage?
Cyst
What is the term used to describe the complication that may arise forming granulation tissues or tumors created by the Entamoeba Histolytica?
Amebomas (Amebic Granulomas)
Asymptomatic carriers make up 75% in endemic areas and 30% of general population, what is the Non-pathogenic form often named or is mistaken for?
Entamoeba Dispar (E. Dispar)
What is the Geographic distribution of Entamoeba histolytica?
Cosmopolitan, Prevalent in Tropic and Subtropics
-Areas of poor sanitary and hygienic practices
What is the Infective stage of Entamoeba Histolytica?
- Mature Cysts ingested
- Cysts and trophozoites passed in feces
What is the diagnostic Stage of Entamoeba Histolytica infection?
- Ingestion of mature cysts
- Cysts and Trophozoites passed in feces
- Trophozoites
- Cysts
- Extra-intestinal Disease
- Intestinal Disease
- Noninvasive Colonization
What is the specimen of choice for Laboratory Identification of Entamoeba histolytica?
Feces and biopsies
Describe the process of Specimen processing of feces in the Laboratory Identification of Entamoeba histolytica?
- Collect 3 samples: one every other day
- Avoid contact w/water or urine
- Liquid stools: Examine w/in 30 minutes
- Perform direct exam in physiological saline and Lugol’s iodine
- Perform concentration technique
What forms from the breakdown of eosinophilic blood cells and is an indication of bleeding or inflammation of the intestinal mucosa, in which is seen on Microscopic Examination?
Charcot-Leyden Crystals
Trophozoite form of Entamoeba Histolytica has what appearance on Laboratory Identification?
- Cytoplasm: Clean
- Appearance: Fine Granular
- Inclusions: Occasional RBCs (case of dysentery); few bacteria or debris in vaculoles
- Motility (in saline): Directional and progressive w/smooth, lobed pseudopodia
Cyst form of Enamoeba Histolytica has what appearance on Laboratory Identification?
- Shape: Spherical
- Nucleus:
- # : 1-4, mature quadinucleated cyst
- Appearance: Fine Granular
What parasite is often confused with Enamoeba histolytica however is nonpathogenic and infection indicates a breakdown in hygienic and sanitary environment of host?
Entamoeba coli
What is the Geographical distribution of Entamoeba coli?
Cosmopolitan
What is the specimen of choice for Entamoeba coli?
Feces
Trophozoite form of Entamoeba coli has what appearance on Laboratory Identification?
Shape: irregular Nucleus: Vesicular, dispersed type -#: 1 -Peripheral chromatin: coarse granules; irregular size and distribution -Karyosome: Small; usually eccentric Nucleoplasm: Clear
The Cytoplasm of Trophozoite form of Entamoeba Coli has what appearance on Laboratory Identification?
- Appearance: Vacuolated, Coarsely Granular
- Inclusions: Yeast (may include Spores of SPHAERITA), molds, bacteria
- Motility: Sluggish; non-directional w/blunt, poorly defined pseudopodia
CYST form of Entamoeba Coli has what appearance on Laboratory Identification?
-Shape: Sperical
-Nuclei: 1-8 (multi-nucleated)
(Mature Cyst characteristically have 8 nuclei, rarely 16
What effect does Giardia lamblia have on intestinal absorption?
Malabsorption
-Lg. #’s attach to intestinal mucosa and block absorption
What parasite inhibits fat absorption w/mechanical and chemical interference, excludes absorption of fat soluble vitamins, primarily Vitamin A?
Giardia lamblia
What is the Geographical distribution of Giardia lamblia?
Cosmopolitan (warm climates)
-Epidemics in U.S. regions, Europe, and Soviet Union
What is the infective form of Giardia Lamblia?
Cyst (Mature quadrinucleated) on contaminated water, food, or hands/fomites w/infective cysts
What is the diagnostic stage of Giardia Lamblia?
Cyst and Trophozoites in stool
-Trophozoites do not survive in environment
What is the Habitat of the Giardia lamblia parasite?
Small intestine
What are the Reservoir Host of the Giardia Lamblia?
Beavers
Small Mammals
Herbivores
What is the infective form and mode of infection for Giardia Lamblia?
-Infective: Mature quadrinucleated cyst
-Mode: Ingestion
(Springs, Creeks, Swimming Pools)
What is the specimen of choice for Laboratory identification of Giardia Lamblia parasite?
Duodenal Contents
Feces
Why must several stool samples be collected for possible Giardia lamblia infection?
Cysts passed on cyclical basis
What test is used to recover Duodenal contents when looking for Giardia lamblia?
Enterotest capsule
Trophozoite form of Giardia Lamblia has what appearance on Laboratory Identification?
Trophozoite Form: “Wry Little Face”
- Shape: Pear-shaped
- Dorsal: Convex
- Ventral: Concave w/sucking disc
- Nucleus: Two (bi-symmetrical arrangement)
The Cytoplasm of the Trophozoite form (“wry little face”) of Giardia Lamblia has what appearance on Laboratory Identification?
Flagella: 8
- Anterior: 2 (cross midline)
- Ventral: 4 (2 behind ventral notch; 2 behind median bodies)
- Caudal: 2 (extending from posterior end)
Cyst form of Giardia Lamblia has what appearance on Laboratory Identification?
-Shape: Ovoid to Ellipsoidal
-Nuclei: 2 to 4
-Cytoplasm:
(Remnants of retracted flagella; axonemes and median bodies)
(Intercystic space between cytoplasm and cyst wall)
Pathogenicity in females causes vaginitis, pruritus, strawberry cervix and males Urethritis, prostatovesiculitis, what parasite?
Trichomonas Vaginalis
What is the habitat and mode of infection for Trichomonas Vaginalis?
- Habitat: Genitourinary Tract
- Mode: Sexual Contact
What is the specimen of choice for Trichomonas Vaginalis?
- Vaginal and Urethral discharges
- Prostatic Exudates
The Trophozoite of Trichomonas Vaginalis can be identified by flagella and undulating membrane, give the number of each?
Flagella: 4 Anterior
Undulating Membrane: 1/3 to 1/2 length of organism
What can be a Sexually transferred infection is considered nonpathogenic, often recovered from diarrheic stools, and is prominent in homosexual communities?
Pentatrichomonas hominis
What is the Habitat and Mode of Infection of Pentatrichomonas hominis?
Habitat: Colon
Mode: Ingestion, Direct contact/Sexual contact
Describe the Trophozoite flagella and undulating membrane of the Pentatrichomonas hominis?
Flagella: 5 Anterior and 1 Posterior
Undulating Membrane: Full length of Organism
What is the specimen of choice for the Laboratory Identification of Pentatrichomonas Hominis?
Feces