Funci Flashcards
Dermatophytes
Types :
Tricophyton Epidermophyton Microsporium
Mucocutaneous fungal infection . Resides on skin. Eats keratin
Infect skin hair nails
Cause scaling and pruritus
Serious morbidity rarely fatal
Tinea corporis
Infx of hairless skin of body
Tinea cruris
Involvement of groin in infection
More common in males
Tinea pedis
Foot infx
Tinea capitis
Scalp infx
Onychomycosis
Nail infx
Opportunistic mycoses
Candida spp.
Cryptococcus neoformans
Part of normal flora
Low virulence
Endemic/systemic mycoses
Histo plasma capsulatum
Blastomyces dermatitidis
Got from environment
Primary infx in lung then spreads
Ergosterol
Impt part of cell membrane
Exploited in antifungal drugs
Polyenes bind it and cause pore formation
Azoles& Allylamines disrupts its synthesis
Glucan
B-1,3 linkages of glucose in cell wall
Chitin
Glycoprotein
B1,4 linked N acetlyglucosamine residues
Dimorphic fungi
Grow in yeast or mold form
Ie. candida
Chlamydospore
Thick walled fungal spore derived from hyphae cell
Fxn as resting spore
In candida
Conidia
Spore made asexually at tip of hyphae
Mold
Multicellular colonies of clumps of hyphae
Yeast
Unicellular growth
Spherical/ellipsoidal
Reproduction via budding
Tinea versicolor
Skin infx. By non-dermatophytes, dimorphic fungus = Maladsrzia furfur
Causes lesions/macular/papules/patches
On chest back shoulders
Hypopigmented on dark skin
Subcutaneous mycosis
Deep layers of skin like cornea
Remain localized in deep tissue
Cause abscess formation, ulcers,drain sinus tests
Immune system causes host tissue destruction
Keratomycosis
Fungal infx of cornea
Happens with trauma to eye
Fusarium keratitis
Gets feathery central corneal infiltrate in pupil area
Satellite lesions in cornea
Exogenous endophthalmitis
Associated w/ trauma or surgery where organism is introduced directly to ocular structures
Ie. candida or aspergillus
Endogenous enophthalmitis
Caused by candida or aspergillus
Candida albicans symptoms
Oral thrush
Diaper rash
Vaginitis
Systemic infx in ppl w/ HIV
Candida albicans diagnosis
Culture or microscope w/ Calcofluor white /KOH
FOR deep organ infx: blood culture
Acanthamoeba manifestation
Cause keratitis in immunocompetent ppl
Cause granulomatous amebic ENCEPHALITIS N DISSEMINATION INFX in immunocompromised ppl
Trophozoite
Life stage of acanthamoeba
Motile
Active
Favourable conditions
Cyst
Acanthamoeba life stage
Under unfavourable conditions
Bilaminated cellulose wall
Ancanthamoeba Pathology stage 1
Binding to cornea - corneal damage upregulates mannose receptors on cornea
trophozoite binds mannose receptors MBP
Binding induces CYTOLOYTIC PROTEIN MIP33 which degrades epithelial tissue
Phagocytosis of corneal cells
Ancanthamoeba pathology phase 2
Trophozoite breaks bowmans membrane
Cause stromal destruction by proteases, MIP33, aPA= acanthamoeba plasminogen activator (degrades extracellular matrix)
Radial keratoneuritis
Presentation of acanthamoeba
Midstroma begins paracentrally–> limbus in radial patten