micro 6 Flashcards
opportunistic mycoses target immunocomprimised, what are the main types
aspergillosis
mucoromycosis
talaromycosis
pneumocystosis
important species of aspergillosis
a. fumigatus
a. flavus
the clinical presentation of aspergillosis depends on immune system , what are the types
allergic bronchopulmonary aspergillosis (ABPA) Aspergillosis bronchitis aspergilloma invasive aspergillosis semi invasive aspergillosis
explain allergic bronchopulmonary aspergillosis
complex HS rxn seen in asthma patients
early type 1 IgE (mucus and bronchospasm)
late type 3 igG (bronchial wall damage and bronchiectasis)
explain aspergillus bronchitis
fungal growth in diseased lung (symptoms of underlying cause)
explain aspergilloma
growth in pre exist lung cavity forming a fungus ball ( fungus, mucus and inflammatory cells) , its asymp but maybe hemoptysis
explain invasive aspergillosis
affect severly immunocomprimised
endobronchial fungal growth and BV invasion causing thrombosis and lung infarction (angioinvasive)
semi invasive aspergillosis explain it
similar to invasive but less immunocomprimised
culturing aspergillosis is easy and may represent colonization or decontamination but positive results should be interpreted based on
type of sample
clinical info
histopathological pic of tissue
radiological pic
antigen detection of aspergillosis what tests
galactomannan and beta-D-glucan
treatment of ABPA
oral corticosteriod and in refractory fases omalizumab (against igE)
Aspergilloma treatment
intracavity administration of amphotericin B and bronchail artery embolization
invasive aspergillosis treatement
voriconazole is first line or amphotericin B
what fungus can cause mucormycosis
mucor
rhizomucor
rhizopus
risk factors of mucoromycosis
immunosuppression (hematological malignancy and post transplant )
diabetes and IV drug abuse
three main clinical presentation of mucormycosis
rhinocerebral
pulmonary
cutaneous
rhinocerebral mucormycosis is most common presentation in who
IV drug abuser and DM
pulmonary mucormycosis is most common presentation in who
hematology patient
what mucormycosis mimics invasive aspergillosis
pulmonary
what mucormycosis has an acute invasive infection in orbit , meningis…
rhinocerebral
treatment of mucormycosis
DOC amphotericin B and surgical debridement
talaromycosis caused by
talaromyces marneffei
patient that has talaromycosis present with
fever, weight loss, hepatospleenemagly and LAP
What can talaromycosis do to lung and face and skin
lung ; cavitation (hemoptysis)
face and skin ; papulonodular skin lesion
talaromycosis and pneumocystosis diagnosed by
microscopic examination
culture of talaromycosis shows
dimorphism
mild talaromycosis treated with
itraconazole
severe talaromycosis treated with
amphotericin B
pneumocystosis caused by
pneumocystis jirovecii
what two infections where classically associated with AIDS
talaromycosis and pneumocystosis
what is the life cycle in pneumocystosis
asexual and sexual
hallmark of pneumocystosis infection
interstitial pneumpnitis (pneumocystis pneumnitis / PCP)
Radiologically lungs in pneumocystosis show
perihilar ground glass appearance
first line to treat pneumocystosis/ PCP
co-trimoxazole
thermally dimorphic systemic fungal pathogens means
mold at 25-30
yeast at 37
no evidence of human to human transmission in systemic fungal pathogens
true
main types of systemic mycoses
blastomycosis
histoplasmosis
coccidomycosis
paracoccidomycosis
blastomycosis caused by
blastomyces dermatidis
ecological niche of blastomycosis
decaying organic matter
infection of blastomycosis due to
inhalation of conida
who is more susceptible to blastomycosis than humans
dogs
blastomycosis can cause
pulmonary blastomycosis and extrapulmonary blastomycosis
pulmonary blastomycosis is
asymp or mild flu like
extrapulmonary blastomycosis mainly affects
skin (due to hematogenous spread from lung )
blastomycosis diagnosed through
microscopy shows double contoured broad based budding yeast
is mold form diagnostic in blastomycosis
no
mild or moderate blastomycosis treated with
itraconazole
severe blastomycosis treated with
amophotericin B
What causes histoplasmosis
histoplasma capsulatum
ecological niche of histoplasmosis
soil with high nitrogen bird and bat dropping
what two forms of histoplasmosis
american / classical
african
classical histoplasmosis can be pulmonary or disseminated
true
classical histoplasmosis pulmonary causes what
mediastinal fibrosis if chronic
african histoplasmosis affects
skin and bone
microscopy of histoplasmosis shows
narrow based budding yeast
treatment of histoplasmosis
mild and moderate : itraconazole
severe : amphotericin B
(LIKE BLASTOMYCOSIS)
Inhalation of conida of histoplasmosis is phagocytosed by pulmonary macrophage and neutrophils where they germinate to yeast
true
what causes coccidioides
coccidioides immitis
where is coccidioides fungus found
soil its growth enhanced by rodent and bat dropping
coccidioides present in what 2 forms
primary and secondary
when does secondary coccidioides happen
sympromatic for 6 weeks or longer
microscopy of coccidioides shows
endosporulating spherules
culture of coccidioides shows
barrel shaped arthroconida in mold form
paracoccidioides caused by
paarcoccidioides brasilienses
after inhalation of paracoccidioides fungus the majority will be asymp or symp
asymp (95%)
what are the 2 clinical courses of paracoccidioides
acute/ subacute and chronic
acute/ subacute paracoccidioides happens in what age group and what organ it affects
children and below 30 not pulmonary (LAP and HSM)
chronic paracoccidioides happens why and where
reactivation of primary
pulmonary
microscopy of paracoccidioides
yeast pilot wheel
is mold yielded by culture diagnostic for paracoccidioides
no
paragonimiasis caused by
paragonimus westermanii (trematode)
life cycle of paragonimus
- released in sputum or stool and eggs hatch to miracidia
- miracidia infect snail and form cercaria
- cercaria released into water and infect crustacens where they become metacercarciae
- when ingested metacercariae would excyst into stomach to reach lung where it resides
what is the 1st and 2nd intermediate host for paragonimus
1st is snail
2nd crustacean
paragonimus diagnosed through
operculated eggs visualizing
paragonimus treated with
praziquantel and triclabendazole
clinical feature of paragonimus due to
larval migration (high eosinophilia)
residence of adult worm in lung
ectopic residence of adult worm
cause of cerebral paragonmiassis
ectopic residence of adult worm in CNS
