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Opportunistic Fungal Infections: T-cell mediated immune deficiency Generally are YEASTS2009 Mark Tuttle

Name iagnosis Symptoms !at"ogenesis Treatment

Cryptococcusneoformans

neoformans throughout USA(pigeon shit)

gatti restrictedto warmer areas(Eucalptus tree!"ritish#olum$ia)Two di%ersestrains mated

new truepat"ogenicstrain

! &rows as an encapsulated #uddingyeastin vitro andin vivo

Anamorph' "udding eastTelomorph' "asidiospores ilamentous

*ot en%ironmentall controlled

*ot dimorphic

! Suspect in patients withT-cellmediated immune deficiency$especially:o A+,S

o -igh dose steroids

o Sarcoid treatment

o #hemotherap patients

! .ulmonar inection initiall /dissemination

! ung disease ma $e se%ere1 $utusually inapparento easts3$asidiospores are

inectious

! ,issemination usuall to %NSands&ino #an get meningitis

o &elatinous growth in meninges will

show capsular polsaccharide

Encapsulated east in %i%o and in %itro

4irulence actors! Acidic capsular

polsaccharide

*egati%e charge repulse

Antiphagoctic

T!+ndependent antigen 5$ser%a$le in +ndia +nk

! .henolo6idase

56idi7es phenolics toorm a deep pigmentsimilar to melanin

4alua$le in in%asion o#*S

! Amp"otericin 'and (-F%(suicidenuc)

! A7oles

)a#s

#ulture' 'ird seed agar! &rows as dar&colon $3c

phenolo6idase! #andida al$icans grows*"ite8apid antigen detection test! )ate+ agglutination test for

capsule! Especiall useul or #S (meningitis)

Pneumocystisjirovecii

#sts

! Ma:or cause o pneumonia in AIS! Thought it was a proto7oan initiall

! 8apid progression o pneumonia o%ermatter o das

! -uman3animal strains notcross contagious

! +ntereres with o6gendiusion in al%eoli

! .rophlactictreatment when#,; is

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SupericialSkin3mucosalinection 5*

especially:o ia#etes1 T!cell deicienc

! +n areas where skin remains wet'o Mouth corners (,entures)1 ingers

$arium leak! 4aginitis' satellite lesions and cottage

cheese discharge! inlammation3erosion %s= Malassezia

epidermal growth

Opportunistic Fungal Infections: Neutrop"il immune deficiency Generally are /O)S 2009Mark Tuttle

Name iagnosis Symptoms !at"ogenesis Treatment

Aspergillusfumigates

,

flavus,niger

Septate hphae1

$ranching at ;BC

! /oldproducing a$undant#lastoconidiaon conidiop"ores

! 5n composts and rotting plantmaterials

! Septate $ranching hphaeDangiotrophic

! Fusariummimics growth pattern $utis rare (#ontact lenses)

! More and more seen post $onemarrow transplant

! Sporegerm

tu$ehphae3mcelium

! Infects ia lungsunless in:ected somehow See aircrescent

! .ulmonar phagoctes ail to kill spores in with "ig" dose steroidtreatment

! -phae $ranch (usuall at ;BC)1 e6pands and penetrates $lood %esselwalls

+narcts ollow "4 penetration! -phae in lung present pro#lem of si,e$ut normal neutrophils are

eecti%e at killing them with 0eactie O+ygen$ 12O2$/yelopero+idase$ and %l-

*on!neutropenic complications! Aspergilloma' &rows in a $all in a pre!e6isting scarred ca%it

(T"3Sarcoid)

#orrodes edge danger o hemoptsis (coughing $lood)

&rows saprophticall outside the reach o the immune sstem

Treatment' *eed surger See aircrescent

! Allergic #ronc"opulmonary aspergillosis

Spores germinate in $ronchioles and $egin to grow

Allergic mucus response leads to plugging o $ronchioles= A"s

Signiicantl reduced lung capacit

! Ne*er a,oles(4oricona7ole3

.oscaona7ole)replacingamphotericin "

! Treat on suspicion$ecause o rapidprogression

)a#s

#ulture' &rows %er well at ;BC##T scan' Air crescent in lungs(e6cept in people with a$solutel noneutrophils)"iopsonFt see in $lood sample usuallG

Zygomycetes

Sporangiospores

Aseptate hphae

! Anamorphs' sporangiospores! &erminate to orm hphae3mcelium

3ide$ aseptate$ irregular "yp"ae! Much rarer thanAspergillus! #an get coinection withAspergillus

8hinocere$ral 7gomcosis! +nection %ia nasal tur$inates and

sinuses into #*S (lethal in $rain)! ON)Y dia#etics *it"

&etoacidosis"one marrow transplant recipients! &et 7gomacosis when gi%en

%oricona7ole3posacona7oleprophlacticall orAspergillus

! 4sually ia lung *it"dissemination$ #ut can occur

ia GI and *ounds! -phae are angiotrophic! Iron stimulates gro*t"

! 0esistant toa,oles$ including

resistance tone*er a,oles:4oricona7ole3.oscona7ole

! /4ST 4SEamp"otericin '

Candidaalbicans+n%asi%e,eep!seated1sstemic

! See 'OT1 yeasts and "yp"ae intissuesalso in Tinea 4ersicolor(Malassezia) $ut these arenoninlammator3locali7ed

#ulture (Sara$ound agar)! On lo* Glucose and p%O25

yeast conerts to filamentous

! Serious skin and mucosalinections do notcausedisseminated disease unlessneutropenia de%elops

#hronic Muscocutaneous#andidiasis

! NOT respiratory route ofinfection

! Infect ia GI and ind*ellingcat"eters

! *ormal lora o mucosalsuraces

! ,issemination to ee1 %itreous

! Some speciesresistant to

lucona7olethus

important toidenti speciesD$ased on patternsof sugar

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.seudohphae

#hlamdospore

form! east' !seudo"yp"ae

(Elongated $udding east)! ilamentous' %"lamydospore66

iagnostic for Candida albicans(and Candida dubliniensis)

Germ Tu#e test(Mi6 Candidaw3serum)! C. albicans(andC. dubliniensis)will

orm germ tu$es

! 8are! #andida on dryskin and nails! Masses o anti$odies! Suscepti$ilit is multiactorial

o T!cell anerg or Candida

o Hinc deicienc (Treat

w3HincGG)o Endocrinopath

luid1 heart.henotpe switching (@0!B)! *ot a product o mutation! Switches morpholog and

meta$olism! Enhances a$ilit to thri%e in

dierent en%ironments! #an de%elop resistance to

drugs

! #an de%elop antiphagocitosis

assimilation

Al

gae!! ,iarrhea (prouse $leeding1 malodorous1 90I -251 steatorrhea1 similar to anthra6e$olaids)