Likely get naegleria meningitis from ____ (source/ activity)
Warm Fresh Water, swimming
When swimming, what stage life cycle of naegleria can get in your nose?
Flagellated trophozoite
Primary amebic meningoencephalitis (PAM) is caused by _____, and clinical presentation may include abnormalities in _____ or ______ because it affects the _____ nerve
Naegleria
Taste or smell
Olfactory nerve
Purulent meningitis and encephalitis describes:
Primary amebic meningocenphalitis caused by Naegleria
Primary amebic meningoencephalitis starts by resembling ___ meningitis and progresses to symptoms of ____ including confusion and seizures
Bacterial meningitis like at first
Progress into encephalitis
Brain damage ( hemorrhage and necrosis) in PAM is mostly see in which part of the brain?
Frontal cortex, cuz of damage to the olfactory nerve
Infective stage of Naegleria:
Ameboid trophozoites (have ameboid like legs to help them move)
This is also the feeding stage
Sensitive to the environment
T/F: Naegleria has trophozoites that are resistant to chlorine
False; their cysts are resistant to chlorine because they are just resistant to the environment in general. Able to survive when it’s cold or when the food is scarce
T/F: Naegleria can be transmitted by person to person contact and by drinking contaminated water
False! It can really only be transmitted when contaminated water goes up the nose, rarely by contaminated tap water, poorly chlorinated pool and not by drinking contaminated water or person-person transmission
In the US, naegleria infection is usually found in _____ states
States in the south, (not just southern states): ie CA, NV, AZ, NM, TX included
T/F: Naegleria infection usually occur in healthy people, such as children in the summer months
True
Once the trophozoite of Naegleria reaches the brain, what immune response is produced?
Severe purulent, hemorrhagic inflammatory response
Diagnosis of Naegleria?
CSF to visualize the trophozoites using Giemsa-Wright stain
See nucleus inside the trophozoite
T/F: Naegleria is rapidly fatal, although rare. Often misdiagnosed as bacterial meningitis
True; so won’t see the nucleated trophozoite until autopsy
Which is the only human fungal pathogen that has a capsule?
Cryptococcus
Which cryptococcal species targets immunocompromised hosts and which one is immunocompetent host
Immunocompromised: C. neoformans
Immunocompetent: C gattii
Environmental source of C neoformans vs C gattii
C neoformans: bird droppings
C gattii: eucalyptus tree
A healthy 40 year old man from the PNW presents with cryptococcal meningitis with some, which species is the cause of his illness and how did he get it?
C gattii
He was probably peeing underneath a eucalyptus tree and Inhaled yeasts to his lungs
What is basidiospores?
Yeast cells/ spores (in this lecture, it is referring to cryptococcus)
T/F: there is no human-human transmission of cryptococcus
True; it is through inhalation of the spores, either comes from bird poop (c neoformans) or eucalyptus tree (c gattii)
What can be appreciated on radiological finding for cryptococcal meningioencephalitis?
Hydrocephalus
(neurocysticercosis can also get hydrocephalus)
(pregnant lady with toxoplasmosis can have babies with hydrocephalus too)
What are soap bubbles?
Brain abscesses.
Can be because of cryptococcal meningoencephalitis
What kind of capsule does Cryptococcus have?
Polysaccharide capsule
Prevent phagocytosis and survive in macrophage
Cryptococcal way of protecting against oxidative killing?
Melanin (dark pigment in cell wall)
Which pathogen secretes phospholipase B, laccase and urease for dissemination and invasion?
Cryptococcus
India ink diagnosis:
Cryptococcus!
Taenia solium is a ____ that causes _____
Tapeworm (pork tapeworm)
Neurocysticercosis
What form of T. solium is found inside of our intestines? What about our poop?
Adults
We poop out eggs, which then the pigs eat our poop and get infected
And then we eat the eggs again from uncooked pig
Cysticercosis is from:
T solium larvae encyst in eyes, muscles or brain
T/F: we ingest the larvae form of T solium when we consume undercooked pork
False; we eat the eggs, not the larvae
Humans are ____ host of T solium
Definitive, where sexual reproduction occurs
T/F: neurocysticercosis is the most common cause of acquired epilepsy in the developing world
True
Presence of _____ in tissue of neurocysticercosis can be seen in imagining
T solium Cysts. Because body cannot get rid of the larvae, so it encyst it
T/F: Toxoplasmosis, a parasitic disease, is the leading cause of focal central nervous system (encephalitis) disease in healthy individuals
False; it is the leading cause of focal CNS disease (encephalitis) in AIDS patients; healthy people with toxoplasmosis is asymptomatic
What pathogen is the most common cause of meningitis in AIDS patients?
Cryptococcus
What are the most common parenchymal brain lesions in AIDS patients with toxoplasmosis?
Multiple-ring-enhancing lesions at the corticomedullary junction
What happens if pregnant lady develops toxoplasmosis?
Can result in miscarriage, stillbirth or congenital toxoplasmosis- which is baby exhibiting hydrocephalus or intracranial calcification, or chorioretinitis (eye thing)
AIDS patients (when CD4 <100) can get what from toxoplasmosis?
Encephalitis
Pneumonitis
Chorioretinitis
What causes congenital toxoplasmosis?
It is toxoplasmosis to infant when the mom is infected with it
Results in hydrocephalus, intracranial calcification and/or chorioretinitis
Toxoplasma is transmitted through?
Cat poop
Oocysts in poop
What is the definitive host for toxoplasma (parasite)? What is the end stage host? What is intermediate host?
Cat is definitive
End stage is us
Intermediate is rat, pig, sheep etc
What form of toxoplasma is released in cat poop?
Oocyst
When toxoplasma is inside a host tissue (like pig, sheep, chicken, bird, rat), it enters a dormant stage forming ______.
Tissue cysts
How can human be infected of toxoplasmosis?
Eat inadequately cooked meat that contains Toxoplasma tissue cysts (ie from intermediate hosts such as pig, sheep)
Ingesting oocysts straight up from cat’s poop
What form of Toxoplasma is found inside of us?
Tachyzoites (also the same form that is passed to fetus congenitally)
Banana shaped
T/F: Toxoplasma is an apicomplexa like plasmodium
True, which means it uses gliding motility
T/F: Toxoplasma is an obligate intracellular parasite
True
T/F: Humans are intermediate host for toxoplasma like virtually all warm-blooded animals, but we are also dead-end hosts unless you’re planning on getting eaten by a cat
True
What is tachyzoite?
Invasive form of Toxoplasma trophozoite found inside of us and not in the environment
Congenital cause
What is bradyzoite?
These infectious tissue cysts of toxoplasma as long as the meat is edible and uncooked
T/F: bradyozites are protected inside an oocyst which are resistant to the environment, the form that is found in cat poops
False; sporozoites are the form that is protected inside the oocyst found in cat poop; bradyzoites are found inside of tissue cysts in intermediate hosts
How is toxoplasmosis diagnosed?
Serology – IgM first, the goes away after the first month, then IgG predominates within 2-3 months in the absence of treatment
Immunofluorescence for IgM
T/F: pregnant women with toxoplasma can be treated with macrolide even though this is a parasitic infection
True. Because toxoplasma has this bacteria-like organelle called apicoplast that contains bacteria-like ribosomes
What does toxoplasma have in terms of its organelle that is a target for antibacterial treatment?
has apicoplast, which is bacteria-like organelle that contains bacteria-like ribosome
So can be treated with erythromycin
Prophylaxis treatment for HIV patient to prevent toxoplasmosis:
