Pulmonary Fungal Infections 2

Question 1

under what kinds of circumstances are opportunistic fungal pathogens dangerous or life threatening?

Answer 1

Prolonged neutropenia, uncontrolled DM, profound T-cell suppression, HIV

Question 2

Effective tx of opportunistic fungal pathogens must address the ______ ______ and the _______ problem.

Answer 2

current infection

underlying problem

Question 3

What does it mean that candida is multimorphic?

Answer 3

it has yeastlike, pseudohyphal, and hyphal forms that may ALL be present in the same infection at the same disease site

Question 4

Describe the presentation of candidiasis

Answer 4

thrush
vaginitis
diaper rash
chronic mucocutanteous 
disseminated

Question 5

How do you diagnose cadidiasis?

Answer 5

exam, biopsy, +/- CT

Question 6

How do you treat cadidiasis?

Answer 6

azole appropriate to site of infection, few types require amphotericin B

Question 7

T/F: Candida is very unlikely to develop drug resistance

Answer 7

FALSE! candida may develop resistance and should be tested for sensitivity

Question 8

Where do you find cryptococcus?

Answer 8

widespread in the environment, soil from bird and bat feces

Question 9

Where is candida normally found?

Answer 9

NORMAL FLORA

Question 10

What is unique about candida gram stain?

Answer 10

it is gram +

Question 11

What predisposes a person to cryptococcal infection?

Answer 11

reduced CMI

Question 12

What is unique about the cryptococcal effect on the host?

Answer 12

it suppresses the host inflammatory response

Question 13

T/F: cryptococcus is dimorphic

Answer 13

FALSE - looks like oval budding yeast

Question 14

How does cryptococcus present?

Answer 14

late in disease (presumably because of reduced inflammatory response) –> meningitis, skin nodules, pulm sx

Question 15

how do you diagnose cryptococcus?

Answer 15

biopsy, CSF, crag

Question 16

what is “crag”

Answer 16

serologic test for cryptococcal infection: CRyptococcal AntiGen

Question 17

How is cryptococcus transmitted?

Answer 17

inhalation

Question 18

What form does aspergillus take?

Answer 18

Not dimorphic, ONLY MOLD: septate hyphae with V-shaped branches

Question 19

where is aspergillus found?

Answer 19

widespread on decaying vegetation worldwide

Question 20

how is aspergillus transmitted?

Answer 20

inhalation of infectious conidia:

colonize abraded skin, burns, cornea, ear, sinuses

Question 21

What virulence factors are present in aspergillus?

Answer 21

gliotoxin (immunosuppressive)
toxic metabolites
proteases

Question 22

What are the four presentations of aspergillus?

Answer 22

ABPA= allergic bronchopulmonary aspergillosis
Aspergilloma
CNPA= chronic necrotizing pulm aspergillosis
Invasive

Question 23

Which of the four presentations of aspergillus is a hypersensitivity rxn to infection that complicates asthma of CF? and how do you dx this form? Tx?

Answer 23

ABPA
dx on exam
tx: itraconazole, sinus surgery, Xolair

Question 24

Name this form of aspergillus: fungus ball complicating cavitary lung disease
dx?
tx?

Answer 24

aspergilloma

dx: air crescent on CT
tx: itraconazole +/- surgery

Question 25

Which form of aspergillus mimics TB? dx? tx?

Answer 25

CNPA air crescent on scan, needle biopsy for histology tx; amphotericin b, immune reconstitution, surgical resection prognosis POOR

Question 26

how does CNPA present?

Answer 26

resp distress with hx of profound immunosuppression

Question 27

how do you treat invasive aspergillus?

Answer 27

same as CNPA: amphotericin b, immune reconstitution, surgical resection prognosis POOR

Question 28

Name this infection: very rare, deadly invasive vasculitis caused by environmental mold that causes infarction and invades the brain from the sinuses?

Answer 28

mucormycosis

Question 29

what are some predisposing factors for mucormycosis?

Answer 29

uncontrolled DM, iron overload, immunosuppresion

Question 30

tx and dx for mucormycosis?

Answer 30

dx: biopsy--> histo tx: amphotericin b and aggressive surgical removal of diseased tissue POOR prognosis

Question 31

name this infection: ubiquitous environmental mold, infection rare but fatal in predisposed pop. may cause local infection or deadly disseminated infection

Answer 31

fusarium

Question 32

what is mycotoxicosis?

Answer 32

fusarium infection from contaminated grain serious toxicity may be lethal alimentary toxic aleukia

Question 33

fusarium local infections tend to occur in what areas of the body?

Answer 33

burns, prosthetic joints, contaminated contact lens solution (cornea)

Question 34

mucormicosis is caused by what three organisms?

Answer 34

mucor, rhizopus, absidia

Question 35

what are the deadly disseminated forms of fusarium infection?

Answer 35

occurs in immunosuppressed: prolonged neutropenia, HSCT recipients (bone marrow transplant)

Question 36

How do you dx fusarium infection?

Answer 36

blood culture, histo

Question 37

how do you treat fusarium infection?

Answer 37

aggressively with surgery, amphotericin B, voriconazole, poor prognosis

Question 38

describe the entry of fusarium into its human host

Answer 38

enters from sinus or wound, circulates in blood, reaches skin, eye, or lung where sx occur

Question 39

are positive blood cultures more common in fusariosis or aspergillosis??

Answer 39

fusariosis

Question 40

out of the oportunistic mycoses we have studied, which two are most concerning in terms of antifungal resistance?

Answer 40

candidiasis and fusariosis