Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
41 Cards in this Set
- Front
- Back
|
What is Paratism?
|
Conquest of life by life
Way in which one species gains its livelihood at the expense of another; weaker organism obtaining food and shelter from another organism |
|
|
How do parasites avoid our immune system?
|
Shuffle their surface proteins rapidly there by avoiding recognition
|
|
|
What is the life cycle of a parasite?
|
Ability: to establish infection in humans
Latency: Ability to remain quiescent Replication Restriction: in an immunological intolerant host |
|
|
What is the biological principle of parasites?
|
Successful parasites generally DO NOT harm the host
|
|
|
What is Trypanosoma?
|
Ultimate master of disguise; live in blood stream and replaces its coar of proteins every two weeks
Causes sleeping sickness in Africa |
|
|
Are the currently vaccines against parasitic infections?
|
NO
|
|
|
What is the Cyst stage of parasites?
|
The infective stage, stable form, able to resist temperature change
|
|
|
What is the Trophozoites?
|
Metabolically active stage of protozoa, fragile form
|
|
|
What is the Exception which causes disruption of cycle and leaves the organism not infectious?
|
Liquidy diarrhea; organism does not have time to progress back into cyst form
When excreted NOT infectious b/c not in cyst form |
|
|
How do Helminthes cause disease?
|
Cause chronic infection b/c of complexity of genome, multiple developmental stages, antigen variation
Worm like and unremittingly corrosive |
|
|
What is a Nematodes, and what is the name of the type?
|
Round warms
Ascaris Lumbricoides |
|
|
Platyhelminths
|
flat worms
|
|
|
Cestodes
|
tape worms
|
|
|
What are Trematodes?
|
A class with Helminthes referred to as flukes
|
|
|
What type of worm is Ancylostoma Duodenale and what does it cause?
|
Hook worm
Leading cuase of anemia in 3rd world |
|
|
What is the Clinical presentation of worms?
|
Pica, unusual cravings for "junky" food or non-food items, which correlates w/ iron deficiency
|
|
|
What is the pathogenicit of Helminths?
|
Mechanical; due to its tape-like apperance
Invasion and destruction Inflammation Competition for host nutrients Worm burden |
|
|
What are Charcot-Leyden Crystals, how are they made, and where are they seen?
|
By products of eosinophil break down by Helminths
Seen in stool, sputum, etc. |
|
|
What causes Eosonophilia and what is it?
|
Generaly caused by helminth penetration of mucous membrane during migration
Not all heminthes cause eosiophilia A high amount of Eosinophils |
|
|
What is the Procedure for Ova & Parasites (O & P) collection, how many times should it be done, and what can cause a problem?
|
Collect in a waterproof, clean dry container about 30 mL of liquid specimen
Should be repeated on 3 altenate days Vials may contain a preservative Many subsance (urine, water, abx, etc) destroy trophozoites |
|
|
What are parasitologists?
|
"Inward" are psychologists that asseme if a parasite has not been it does not exist
Pt. is a "mental case" |
|
|
What are some examples of Ectoparasites and where do they live?
|
Scabies and head lice
Live on body and integument |
|
|
What is Acanthamoeba, what does it cause, and what type of product does it correlate with?
|
Free living Amoebas
Amoeibic keratitis - w/ use of soft contact lenses |
|
|
What is Naegleria Fowleri, what does it cause and where/who gets it?
|
A free living amoeba that causes Meningo-encephalitis - swimmers/divers (small lake and ponds)
|
|
|
What does the Hygiene Hypothesis state
|
That exposure to microorganisms (decreased) hygiene during early age is important for development ofa balanced immune system - Non-atopic Th1 Cells
Increased hygiene leads to an uncontrolled Th2immune response to allergens resulting in atopic disease |
|
|
PICA
|
compulsive ingestion of non-nutritive substances (ice, dirt, wall paints)
|
|
|
What is Dyssentery and what is it associated with?
|
Perpetual purging of mucus, blood and purulent stools with tenesmis and gripng.
Associated with invasion/inflammation |
|
|
Definitive Host
|
The secual state of parasites life cycle is completed
|
|
|
What is an Intermediate Host and what stage of the lifecylce is taking place?
|
Which the asexual state of parasites life cycle takes place
|
|
|
Oocyst
|
infectious form containing sporozoites
|
|
|
Transmision of Toxoplasmosis (Tocoplasma Gondii)
|
AIDS defining parasite
Ingestion of Oocyst from contaminated sources; soil, CAT LITTER, water, uncooked meat Dogs and Cats are major carriers; cats are shedding cysts (definitive host) Vertical Immunocomprimised pts. |
|
|
Clinical presentation of Toxoplasmosis
|
Flu like illnes w/cervical lymphadenopathy
Opisthotonus - generalized rigidity - congenital Microophtahlmia - ditaled pupil (huge) - congenital |
|
|
What is the infectious organismal form of Toxoplasmosis
|
Tachyzoite, Highly prolific, presence indicats active infection
They disseminate via blood stream to infect CNS, eye, skeletal and heart muscle and placenta They are transformed in Bradyzoites |
|
|
Bradyzoites
|
Dormant but viable form of toxoplasmosis and persist for LIFE of the host
|
|
|
Toxoplasma Encephalitis
|
Focal neurological deficit
Generalized cerbral dysfunction Neuropsychiatric abnormalities Intracerebral calcifications |
|
|
Toxoplasma gondii encephalitis is common among which diseased population, what are clinical manifistations, and what is the CD4 count?
|
common among AIDS patients,
Present with many brain abscesses and as “mental status change” When CD4 count drops below <100/mm3 |
|
|
Congenital Toxo Triad
|
Hydrocephalus, intracerebral calcification, choroidodretinitis
|
|
|
How does Toxo present in immune comptetent host?
|
Generally presents as a flu or infectious mono
most typical manisfestation is isolated cervical or occipital lymphadenpathy Lymph nodes NOT tender stay enlarged for less then 4-6 weeks |
|
|
Presence of waht has been used as indication for termination of a pregnancy with Toxoplasmosis?
|
Hydrocephalus
|
|
|
What is the Pathogenesis of Toxoplasmosis?
|
DTH, strong and persistant Th1 response characterized by production of proinflammatory cytokines; IL-12, IF-G, and TNF-A
|
|
|
What is Spiramycin used to treat and what type of approval does it require?
|
Treatment for acte intra-pardum infection of toxoplasmosis
3g/day and requires aproval from FDA |
