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Flashcards in export_cns fungi Deck (44):
1

Which fungi can cause CNS infections?

Systemic fungi - Histoplasma, Blastomyces, Paracoccidioides, Coccidioides, Cryptococcus

2

What is the leading cause of fungal meningitis?

Cryptococcal

3

Coccidioides immitis important feature

Dimorphic; molds in environment, yeast in tissues

4

Cryptococcus neoformans important feature

Encapsulated yeast in both environment and man

5

Coccidioides immitis life cycle

Mold spores inhaled, then converts into a spherule, which produces hundreds of single nucleated spores

6

Coccidial meningitis

Develops slowly
Headache, fever, stiff neck, other neurological signs

7

Treatment for C. immitis

Amphotericin B

8

Cryptococcus is commonly found where?

In soil contaminated with bird droppings

9

Cryptococcal meningitis symptoms

Develops slowly
Bouts of headaches, irritability, dizziness, other CNS

May present over weeks or months

10

Cryptococcus diagnosis

India Ink stain

11

Treatment for Cryptococcal meningitis

Long term treatment of Amphotericin B and fluconazole
Relapse in AIDS patients is common, may require suppressive therapy

12

Rhinocerebral zygomycosis most commonly affects?

Primarily diabetic patients

13

Symptoms of rhinocerebral zygomycosis

Nasal congestion, blood-tinged rhinorhhea, tender sinuses, headache, fever
Can progress to altered mental status, coma, and death

14

Diagnose zygomycoses

Hyphal elements (broad, aseptate, branching at right angles) in clinical material
Culture

15

Treatment for zygomycoses

Amphotericin B

16

Main parasitic infections

Entamoeba histolytica
Trypanosoma brucei

Plasmodium falciparum

Protozoa

Helminth

17

What does entamoeba histolytica cause in the CNS?

Brain abscesses

18

What does Trypanosoma brucei cause in the CNS?

African sleeping sickness

19

What does Plasmodium falciparum cause in the CNS?

Cerebral malaria

20

What do protozoa's cause in the CNS

Toxoplasmosis

21

What do helminths cause in the CNS?

Cysticercosis

22

Free-living amoeba that can affect the CNS

Acanthamoeba
Naegleria

Balamuthia

23

What does Naegleria cause?

Primary amebic meningoencephalitis (PAM)

24

Symptoms of PAM

Fever, headache, vomiting, confusion
Rapidly progress to coma and death

25

Diagnose Naegleria fowleri

Observation of trophozoites in biopsy material or CSF

26

Treatment of Naegleria fowleri

Infection is usually fatal
Can treat with Amphotericin B, some success is found

27

What do Acanthamoeba and Balamuthia cause?

Granulomatous amoebic encephalitis (GAE)

28

Symptoms of GAE

Amoeba invade brain and cause a slow-developing ulcerative lesion
Slower course of disease than PAM

29

Acanthamoeba keratitis

Chronic infection of the cornea, associated with contact lens usage

30

Toxoplasma gondii symptoms

Majority of people are asymptomatic
Ocular infections

Encephalitis in immunocompromised

31

Congenital Toxoplasma gondii

Can result in miscarriage or stillbirth
Blindness, mental retardation, neurological disorders if baby makes it to term

32

Toxoplasmosis symptoms

Most are asymptomatic
"Flu like" - fever, headache, chills, lymphadenopathy

33

Toxoplasma gondii life cycle

Parasite infects, then differentiates/disseminates to the muscle, brain, etc.
Immune system "walls off" bradyzoite-filled cyst

Immune weakness can result in reactivation

34

Diagnose Toxoplasma gondii

PCR of amniotic fluid
Maternal IgM or rising IgG (acute)

IgM positive in newborn indicates congential, however not all affected are IgM positive

35

Taenia solium disease

Pork tapeworm

36

Taenia solium dissemination

Larvae hatch in intestines and enter circulation
Travel to various body sites where they encyst

Creates a space filling lesion, inducing local inflammation

37

Neurocysticercosis symptoms

Seizure and neurological defects

38

Diagnose Taenia solium

CT scan, MRI, serology

39

What disease does Ascaris lumbricoides cause in the CNS?

Visceral larval migrans (VLM)

40

What kind of disease is VLM?

Zoonotic; infection by worms that normally infect dogs and cats

41

VLM transmission

Ingestion of eggs

42

VLM life cycle

Humans ingest eggs, larvae hatch and enter bloodstream, can't develop in humans so granulomatous lesions develop (commonly in liver, lung, and eye)

43

Symptoms of VLM

Fever and eosinophilia

44

Treatment of VLM

Primarily symptomatic
Steroids