Toxoplasma Flashcards
diagnosis of toxoplasma in DH? - type of technique
- flotation technique
diagnosis of Toxoplasma in IH - serology?
- Sabin-Feldmann dye test
- CFR
- IFAT
- ELISA
- Latex agglutination test.
diagnosis of Toxoplasma in general
- DH
- IH
- biological assay - mice, cat
- PCR
Toxoplasma gondii - definite host:
- domestic cat, wild felids
- found in the SI - schizogony, gamogony
Intermediate host of Toxoplasma gondii is?
- mammals
- birds
Source of infection of Toxoplasma gondii - what stage and where is it found:
- Tachyzoites – raw goat milk (very rare)
- Tissue cysts – raw meat and meat products
- more than 50% infections in humans
- sporulated oocysts – soil (vegetables), contaminated water
Toxoplasmosis in which humans:
- Immunocompetent individuals:
- Immunocompromised patients (HIV, organ transplants):
- Pregnant women:
Toxoplasmosis in animals:
- Sheep, goats – reproduction problems
- Pallas cats, marsupials, lemurs, New world apes, brown hare – acute fatal toxoplasmosis
genotyping of Toxoplasma gondii
- genotypes I., II., III.,
- recombinant and atypical genotypes
Toxoplasma gondii characteristics:
- Non-sporulated oocyst: shed by felids into environment
- sporulated oocyst in environment
- Tachyzoites in various tissues (in pseudocysts)
- Vertical (transplacental) transmission
- Tissue cysts (bradyzoites): myocard, CNS, skeletal muscles
what type of transmission is used by Toxoplasma?
- Vertical (transplacental) transmission
Tissue cysts AKA … of toxoplsama is found in what tissues?
- bradyzoites
- myocardium, CNS, skeletal muscles
- raw meat and meat products - source of infection
Non-sporulated oocyst of Toxoplasma gondii is found where?
- shed by felids into environment
Sporulated oocyst of Toxoplasma gondii is found where?
- sporulated oocyst in external environment
- soil (vegetables), contaminated water - source of infection
Where is Tachyzoites of Toxoplasma gondii found?
- in various tissues (in pseudocysts)
- visceral organs
- raw goat milk (very rare) - source of infection
Toxoplasma gondii picture:
Diagnosis of Toxoplasma gondii:
- Flotation technique:
- Necropsy:
- Impression smear:
- Histological examination:
- Immunology:
- Serological examination:
- biological assay:
- Molecular techniques:
molecular techniques of Toxoplasma gondii:
- detection of T. gondii DNA
- PCR: conventional, real-time
- genotyping
Biological assay of Toxoplasma gondii:
golden standard:
- Mice – tissue cysts detection
- Cat – sporulated oocysts detection
Histological examination of T. gondii
Serological examination of Toxoplasma gondii:
detection of antibodies against T. gondii:
- IgM: acute phase – within one week post infection, peak concentration 3-6 weeks post infection, disappear after one year
- IgG: 3 weeks post infection, peak concentration 2-3 months post infection, lifetime last in lower titres
- Antibody titers dynamic !!!
- Qualitative tests: LAT – total antibodies
- Quantitative tests: IFAT
- IgG and IgM differentiation, antibody titres detection
- Suitable for individual samples
- ELISA
- ODR value = optical density
- Automatical method, suitable for large amount of samples, meat juice
necropsy of Toxoplasma gondii:
acute toxoplasmosis in sensitive animal species
- Systemic disease affecting multiple organs – pneumonia, enteritis, meningoencephalitis, hepatomegaly, splenomegaly
- European brown hare (Lepus europeaus)
Impression Smear of Toxoplasma gondii:
- Diff-Quick or Hemacolor staining
- in Pallas cat
Flotation technique of Toxoplasma gondii - is used for/characteristics of the parasite:
- detection of oocysts
- Sporulated oocysts: 12x10 μm, 2 sporocysts & 4 sporozoites each
- Sporulation in the environment – up to 21 days (1-5 days)
- Cats are shedding oocysts only during the primoinfection up to 21 days!!!!!
- Misdiagnosed with Hammondia hammondi oocysts
During flotation technique the oocyst of Toxoplasma gondii can be misdiagnosed with:
- Hammondia hammondi oocysts
Toxoplasma gondii oocysts: decribe the picture
- An unsporulated oocyst (blue arrow) and a sporulated oocyst (red arrow) seen at high power (40 X)
- (A) Unsporulated oocyst. Note the central mass (sporont) occupying most of the oocyst.
- (B) Sporulated oocyst with two sporocysts. Four sporozoites (arrows) are visible in one of the sporocysts.
- (C) Transmission electron micrograph of a sporulated oocyst. Note the thin oocyst wall (large arrow), two sporocysts (arrowheads), and sporozoites, one of which is cut longitudinally (small arrows)
Which animals is affected by toxoplasmosis:
- humans
- sheep
- goat
- Pallas cats
- marsupials
- lemurs
- New world apes
- brown hare
which animals is affected by acute fatal toxoplasmosis?
- Pallas cats
- marsupials
- lemurs
- New world apes
- brown hare
Which animals is affceted by reproduction problems caused by Toxoplasma gondii?
- sheep
- goat
how is pregnant women affected by Toxoplasmosis
- abortus
- hydrocephalus
- uveitis
which humans are affcted by Toxoplasmosis?
- pregnant women
- immunocompetent individuals
- immunocompromised patients - HIV, organ transplants
In Immunocompromised patients with Toxoplasmosis we see these symtoms/damages:
- encephalitis
- pneumonia
- vision problems
Toxoplasmosis in immunocompetent individuals is seen as:
- asymptomatic
- lymphadenopathy
what is the percentage of human infections by Toxoplasma gondii?
- more than 50% infections in humans
Immunocompromised patients are those with:
- HIV
- organ transplants
