Protozoa - CNS Flashcards
Which Sketchy image represents Toxoplasma gondii?
Which Sketchy image represents Trypanosoma brucei?
Which Sketchy image represents Naegleria fowleri?
Identify as many of the marked points in this image as you can.
Note: this is Toxoplasma gondii.
Identify as many of the marked points in this image as you can.
Note: this is Trypanosoma brucei.
Identify as many of the marked points in this image as you can.
Note: this is Naegleria fowleri.
Toxoplasma gondii is a protozoan parasite that primarily affects what organ system(s)?
The CNS
What is the definitive host of Toxoplasma gondii?
How do humans contract it?
Cats;
interaction with cat feces
Toxoplasma gondii oocysts are found in ______-blooded animal feces, particularly ____.
Toxoplasma gondii oocysts are found in warm-blooded animal feces, particularly cats.
What patient populations are at higher risk for Toxoplasma gondii infection?
Immunocompromised patients
_______________ lesions on CT/MRI is a feature of cerebral toxoplasmosis in immunocompromised patients (HIV/AIDS).
Multiple, ring-enhancing lesions on CT/MRI is a feature of cerebral toxoplasmosis in immunocompromised patients (HIV/AIDS).
Toxoplasmic encephalitis (_________, _________, multiple _________ lesions) is the most common presentation of Toxoplasma gondii infection in immunocompromised patients.
Toxoplasmic encephalitis (headaches, seizures, multiple ring-enhancing lesions) is the most common presentation of Toxoplasma gondii infection in immunocompromised patients.
How can cerebral toxoplasmosis (multiple ring-enhancing lesions on CT/MRI) be differentiated from CNS lymphoma (often a solitary ring-enhancing lesion on CT/MRI)?
Brain biopsy
Toxoplasma gondii cysts can be found in ___________ meat.
Toxoplasma gondii cysts can be found in undercooked meat.
Congenital toxoplasmosis presents with what classic triad of symptoms?
Intracranial ________;
________/seizures;
chorio_______
Intracranial calcifications;
hydrocephalus/seizures;
chorioretinitis
True/False.
Hearing loss is a possible complication of congenital toxoplasmosis.
True.
Treatment of Toxoplasma gondii consists of what two medications?
Sulfadiazine;
pyrimethamine
Prophylaxis (usually ____________) should be administered to Toxoplasma gondii IgG-positive HIV patients with a CD4+ count of ______ to prevent toxoplasmosis.
Prophylaxis (usually TMP - SMX) should be administered to Toxoplasma gondii IgG-positive HIV patients with a CD4+ count of < 100 to prevent toxoplasmosis.
Prophylaxis (usually TMP - SMX) should be administered to Toxoplasma gondii ____-positive HIV patients with a ____ count of to prevent toxoplasmosis.
Prophylaxis (usually TMP - SMX) should be administered to Toxoplasma gondii IgG-positive HIV patients with a CD4+ count of to prevent toxoplasmosis.
African trypanosomiasis (also known as “sleeping sickness”) is caused by subspecies of what protozoan parasite?
Trypanosoma brucei
(gambiense or rhodesiense)
African trypanosomiasis (also known as “sleeping sickness”) is caused by which subspecies of Trypanosoma brucei?
Gambiense or rhodesiense
What is the vector for Trypanosoma brucei?
What disease does it cause?
The tsetse fly;
African sleeping sickness
Trypanosoma brucei spp. (rhodesiense and Gambiense) are protozoan parasites of what organ system?
The CNS
Trypanosoma brucei infection will lead to what if left untreated?
Coma and death
What two forms of lymphadenopathy may be seen in the early phase of Trypanosoma brucei infection?
Posterior cervical lymphadenopathy and axillary lymphadenopathy
Trypanosoma brucei infection often presents with what kind of fever?
Recurrent fevers
True/False.
Trypanosoma brucei trypomastigotes (mature form) are identified via neural biopsy of the CNS in patients affected by African trypanosomiasis.
False.
Trypanosoma brucei trypomastigotes (mature form) can be seen on peripheral blood smear in African trypanosomiasis
Trypanosoma brucei ___________ (mature form) can be seen on peripheral blood smear in African trypanosomiasis.
Trypanosoma brucei trypomastigotes (mature form) can be seen on peripheral blood smear in African trypanosomiasis.
Why does infection with Trypanosoma brucei cause recurrent fevers in affected patients?
Rapid antigenic variation
Trypanosoma brucei exhibit rapid antigenic variation of what structure(s)?
Surface glycoproteins
How many flagella do Trypanosoma brucei have?
One
What two medications are the main treatments for infection with Trypanosoma brucei?
Melarsoprol;
suramin
True/False.
African sleeping sickness is caused by the bacteria Trypanosoma brucei and is transmitted via the Tetse fly.
False.
African sleeping sickness is caused by the protozoan parasite Trypanosoma brucei and is transmitted via the Tetse fly.
What is Naegleria fowleri?
A protozoan parasite of the CNS
What parasite is associated with freshwater (e.g. lakes, hot springs, water sports, etc.) and some facial cleansers (e.g. nasal cleansers, contact lenses, etc.)?
Naegleria fowleri
How can Naegleria fowleri enter the CNS?
Via the cribriform plate
What rapidly fatal disease can Naegleria fowleri cause?
Primary amebic meningoencephalitis
How is the prognosis for patients affected by primary amebic meningoencephalitis (caused by Naegleria fowleri)?
Poor
(rapidly fatal)
How can Naegleri fowleri be diagnosed?
Lumbar puncture
What medication has been shown to be effective in the treatment of Naegleria fowleri infection (although most cases end in death)?
Amphotericin B
True/False.
Although sometimes deadly, most cases of infection with Naegleria fowleri resolve with few complications.
False.
Most cases of infection with Naegleria fowleri end in death.
