Fungal/Parasite of CNS Flashcards
1
Q
leading cause of fungal meningitis is?
A
cryptococcus
2
Q
systemic fungi can can disseminate into the CNS?
A
Histoplasma, Blastomyces, Paracoccidioides, Coccidioides, and Cryptococcus
3
Q
getting fungal meningitis starts how?
A
inhalation of fungal hyphae or spores - begins with pulmonary inf
4
Q
what are dimorphic fungi? what this means
A
- Histoplasma capsulatum
- Blastomyces dermatitidis
- Paracoccidioides brasiliensis
- Coccidioides immitis
- dimorphic fungi = filamentous molds in the environment; yeast in tissues during infection
5
Q
only systemic fungi that is a yeast in the environment and a yeast in tissues?
A
cryptococcus neoformans (inda ink dude)
6
Q
COCCIDIOIDOMYCOSIS - where is it found?
A
- western hemisphere
- San Joaquin Valley of California and in Southern Arizona
- drought-rain-drought pattern
- blown around in dust
7
Q
Coccidioides immitis - organism info
A
- dimorphic fungus
- arthroconidia are easily airborne
- Following inhalation the fungus converts into a SPHERULE
- multinucleated structure
- produces hundreds of single nucleated spores
- In the environment, spores convert to the mold form; in tissues, they develop into new spherules
8
Q
fungus that is a spherule in tissues?
A
coccidoides immitis
9
Q
Coccidioides immitis - clinical/how it presents
A
- 60% assymptomatic
- Pulmonary disease=Mild to moderate influenza like syndrome: fever, cough, night sweats, malaise and chest pain
- Most individuals spontaneously resolve the infection in 2 to 3 weeks
10
Q
Coccidial meningitis - development
A
-develops slowly with increasing headache, fever, stiff neck, and other neurological signs. If untreated, the disease is frequently fatal.
11
Q
Coccidial meningitis- diagnosis
A
- Cultivation – rarely successful - wont really ever see the spherules - must rely on below two methods
- Antigen detection in CSF
- Serology
12
Q
Coccidial meningitis - treatment
A
amphotericin B
13
Q
Cryptococcosis - found where?
A
-everywhere –. BIRD POOP
14
Q
Cryptococcosis - organism info
A
Cryptococcus neoformans= NOT A DIMORPHIC= IT IS AN Encapsulated yeast
15
Q
Cryptococcosis - pulmonary disease - clinical/symptoms info
A
- Pulmonary disease:
- asymptomatic or a mild, spontaneously resolving, influenza like illness
- little sputum production
- little damage to the lung (granuloma or cavitation)
16
Q
Cryptococcosis meningitis - presentation
A
- develops slowly
- intermittent bouts of headache, irritability, dizziness, and other CNS findings
- Symptoms may present over weeks or months
- Acute onset in immunodef (aids) –> RELAPSE IS COMMON AFTER TREATMENT
17
Q
Cryptococcosis meningitis - diagnosis
A
-India Ink stain can reveal encapsulated yeast in spinal fluid, aspirates from skin lesions, sputum, and other clinical material
positive approximately 50% of the time
-Cultivation
-Serology
18
Q
Cryptococcosis meningitis - treatment
A
- Long term treatment (6-10 weeks)
- Amphotericin B and 5-fluorocytosine or fluconazole.
19
Q
Zygomycoses
A
- in fruits and breads
- susceptibe are: immunosup, diabetes, and burn victims
- not really seen in healthy indiv
20
Q
Zygomycoses types
A
- Rhizopus
- Absidia
- Mucor
21
Q
Zygomycoses organism infor
A
- Non-septate hyphae
- Sporangia bearing sporangiospores
22
Q
Rhinocerebral zygomycosis - infects who most often?
A
diabetics
23
Q
most common form of zygomycosis?
A
Rhinocerebral zygomycosis
24
Q
Rhinocerebral zygomycosis - presentation of disease:
A
- Infection originates in the sinuses (inhalation of spores)
- Extends to neighboring tissues (nose, adjacent sinuses, the hard palate, eye, and brain)
- Initial symptoms include nasal congestion, blood-tinged rhinorrhea, tender sinuses, headache and fever
- Progress to facial or periorbital edema and visual disturbances
- Progression to the brain results in altered mental status, coma and death
25
Zygomycoses - diagnosis
- Observation of hyphal elements in clinical material
- Culture confirmation.
- In tissue section broad aseptate hyphae are frequently observed in blood vessels, frequently branching at right angels (90degrees)
26
Zygomycoses - treatment
amphotericin B
27
hyphae branching 90 degrees/right angles is?
Zygomycoses
28
Entamoeba histolytica can disseminate where?
brain or liver abcesses
29
Trypanosoma brucei causes?
sleeping sickness
30
Plasmodium falciparum causes?
cerebral malaria - coma and die
31
Opportunistic (Free Living) Amoeba - three genera? and found where?
- Acanthamoeba, Naegleria, and Balamuthia
| - in warm fresh water
32
naegleria fowleri causes and presentation?
- -->Primary amebic meningoencephalitis (PAM)
- swimming in warm water (hot springs, heated pools, hot tubs).
- southern US
- associated with neti pots (used to irrigate nasal passages
- gets in through: Intranasal inoculation.
- The majority of cases are fatal within 1 week.
- Symptoms begin as fever, headache, vomiting, and confusion, and rapidly progress to coma and death.
33
Primary amebic meningoencephalitis (PAM) caused by and diagnosis?
- Naegleria fowleri
| - observation of trophozoites in biopsy material or cerebrospinal fluid.
34
Primary amebic meningoencephalitis (PAM) - treatment?
-sometmies Amphotericin B helps
35
Acanthamoeba causes and presenation?
- Granulomatous amoebic encephalitis (GAE
- Amoeba invade the brain, resulting in a slowly developing ulcerative lesion.
* **-Course of disease is slower (1-2 weeks) than PAM.
36
Balamuthia causes and presentation?
- Granulomatous amoebic encephalitis (GAE
- Amoeba invade the brain, resulting in a slowly developing ulcerative lesion.
* **-Course of disease is slower (1-2 weeks) than PAM.
- infections in AIDS patients may disseminate
37
Granulomatous amoebic encephalitis (GAE caused by and diagnosis?
-Caused by Acanthamoeba and Balamuthia
38
Acanthamoeba keratitis - what is it? how do you get it? how do you treat it?
- Chronic infection of cornea.
- Associated with contact lens use (85% of cases), and “homemade” or contaminated cleaning solutions or saline.
- Corneal ulceration and ocular pain.
- Topical treatment may be effective.
- Corneal transplantation / Eye enucleation.
39
Toxoplasma gondii - causes what disease and what are sources of infection?
- cats, -birds and rodens-->GI infection and gets into the poop - Cysts --> to humans
- pork/lamb/goats.. food born -- cysts in that and we eat it undercooked.
40
Toxoplasma gondii - symptoms? why worry about it?
- most asymptomatic!
- but issue bc it can be acquired congenitally = miscarriage or stillbirth OR blind, mental retardation, neurological disorders
- ACUTE INFECTIONS ARE MOST DANGEROUS TO THE FETUS- thats when it can cross over to kid and start causing problems
41
Toxoplasmosis ocular infection
-asymptomatic lesions in eye
42
Toxoplasmosis in HIV/AIDS
- encephalitis - lesion in brain - ring looking
| - most AIDS patients get this
43
Toxoplasmosis-caused by and disease presentation in normal vs immunodef
- Toxoplasma gondii
- Most infections are asymptomatic
- Symptomatic disease – “flu like”: fever, headache, chills, lymphadenopathy, muscle aches
- Following infection (ingestion) parasite goes through a process of differentiation and dissemination (muscle, brain).-->The immune system “walls off” bradyzoite filled cyst.
- When the immune system is weakened reactivation can occur.
44
Toxoplasmosis diagnosis
- Diagnosis is generally made by serological testing.
- Congenital infection may be tested by PCR analysis of amniotic fluid.
- Maternal testing: IgM or rising IgG titer indicates acute infection
- Newborn testing: IgM indicates congenital infection, however not all infected newborns are IgM positive.
45
Toxoplasmosis- prvention/control
- Cooking meat thoroughly.
| - Avoid contact with cat feces: Pregnant & Immunosuppressed
46
Toxoplasmosis- treatment
- Most immunocompetent individuals do not require therapy
- In pregnant mother, early treatment may reduce the severity of disease if transplacental transmission has occurred
- Children with congenital disease should be treated for one year
- Immunosuppressed patients may require prophylactic therapy to prevent reactivation
47
Taenia solium is found where and transmission?
- PORK
| - eating encysted larvae in undercooked meat
48
Taenia solium -extra-intestinal disease?
- Ingested eggs hatch in intestine and release infectious larvae which enter the circulation and travel to various body sites where they encyst.
- striated muscle, heart, brain, eyes
- complications: Neurocysticercosis - seizure and neurological defects
49
Taenia solium - diagnosis for Extra-intestinal
CT scan, MRI. Serology
50
Ascariasis-Ascaris lumbricoides
- the guys that we eat an egg it develops and gets up into lungs we clear throat and swallow and restart cycle
- causes Visceral Larval Migrans
51
Visceral Larval Migrans - where do humans get this from?
-The infection of man by ascarid worms which normally infect and cause intestinal disease in dogs and cats
52
Toxocara canis and T. cati - transmission
-the accidental ingestion of eggs that are in dog and cat poop
53
Toxocara canis and T. cati - in humans:
- (Visceral Larval Migrans)
- Humans ingest eggs, which hatch in the intestine releasing larvae.
- Larvae enter bloodstream and migrate to numerous body sites.
- Development is arrested in humans.
- Granulomatous lesions develop. Commonly in the liver (hepatitis), spleen, lung (cough, wheezing), eye.
- Eosinophilia
- HUMANS DONT POOP THESE GUYS OUT - ONLY CATS AND DOGS
54
Visceral Larval Migrans - symptoms:
- FEVER and eosinophilia
- Lesions in the brain can result in the development of epilepsy or encephalopathy
- Eye infections are most common: “squinting” or a loss of visual acuity; retinal scarring; eye enucleation may be necessary
55
eosinophilia seen in:
Toxocara canis and T. cati (ascardis) - Visceral Larval Migrans -
56
Visceral Larval Migrans - diagnosis
eosinophilia, clinical presentation, serology, history (pets)
57
Visceral Larval Migrans - treatment
can only treat symptoms - steroids - the worms will eventually die on their own
