M2: Opportunistic Mycoses Flashcards
TYPES OFOPPORTUNISTIC MYCOSES
● Candidiasis, systemic
● Cryptococcosis
● Aspergillosis
● Zygomycosis/ Mucormycosis
● Hyalohyphomycosis
● Pneumocystosis
● Mostfrequently encountered
● Endogenousinorigin or nosocomial
● Fungemia&disseminated infection
Candidiasis
Fungal infections in the body which occur almost exclusively in immunocompromised individuals
OPPORTUNISTIC MYCOSES
glycolytic enzyme; immunodominant antigen in
disseminated infections
Enolase
Predisposing Factors- Candidiasis
● Alteration in the normal skin and mucous membrane barriers
● Prolongedantibiotic administration
● Useof immunosuppressive drugs
● Diseasesof the immune system
breakdown of protein structures
Proteases
family or proteins produced by cells usually in response to exposure to stressful conditions
Heat shock proteins
○ seenon5%newborns,10%elderly patients
○ commonly seen on immunocompromised patients
with Diabetes mellitus, leukemia, lymphoma,
neutropenia, HIV
○ rarelyseenhealthy adults
OROPHARYNGEALCANDIDIASIS
Clinical Manifestations- Candida spp.
Perleche
Oral thrush
Vulvovaginitis
Eye infections
commonly seen on folds of skin such as the axillary area, groin, submammary folds etc; skin barrier is damaged due to constant exposure to heat and friction
Intertrigo
infection usually occur underneath the nails causing it to weaken and produce too much nail debris
Chronic Candida Onychomycosis
infection of the fingernails, especially around the cuticle area
Paronychia
colors produced by the ff:
- C.albicans
- C. tropicalis
- C. glabrata
- C. krusei
- green
- blue
- purple
- pink
useful in differentiation Candida spp. as they are
allowed to produce different colors
CHROMAGAR CANDIDA
Identification of Candida spp.a nd other yeasts
CORNMEAL AGAR WITH TWEEN 80
stimulates the conidiation by reducing the surface tension of the culture media
Tween 80
Aprocedureonplanting organisms on either rice meal agar or corn meal agar to allow conidiation
DALMAU PLATE TECHNIQUE
● hypha-like extension with no constriction at the point of origin
○ looklikes it was pulled away from the mother cell
● formeduponincubation w/ serum at 37°C for 1-3 hours
● similar to pseudohyphae but it has construction
GERM TUBE
An acute, subacute or chronic fungal infection that has several manifestations
● infections are mild or asymptomatic, or does not require antifungal treatment for immunocompetent individuals
CRYPTOCOCCOSIS
Etiologic Agents- Cryptococcus spp.
- primarily present in soil contaminated with bird
dropping, particularly of pigeons
C. neoformans
Etiologic Agents- Cryptococcus spp.
- usually present in soil around trees
C. gattii
cryptococcosis culture medias used
Niger Seed Agar
SDA without cycloheximide
Identification of Yeast Cells: for cryptococcal capsular antigen
Latex test
CRYPTOCOCCOSIS TREATMENT:
- For localized pulmonary disease
- For meningitis or other severe infection
fluconazole
amphotericin B
● Infection, usually of the lungs, caused by Aspergillus spp.
● Immunocompetent individuals may be asymptomatic
● Acquired through inhalation
ASPERGILLOSIS
apregillus spp that is the mostcommonagent isolated in immunocompromised individuals
Aspergillus fumigatus
manifestations of aspergiillosis
● Invasivelung infection (common)
● Pulmonary or sinus fungus ball
● Allergic bronchopulmonary aspergillosis
● Cerebral aspergillosis
● Disseminated types: (immunocompromised)
○ Keratitis, otomycosis
○ Onychomycosis
○ Sinusitis, endocarditis, CNS infection
apregillus spp that is difficult to isolate
Aspergillus terreus
apregillus spp that is commonlyisolated from fungus ball and otitis externa
Aspergillus niger
An infection caused by a diverse group of fungal organisms either from the order Mucorales
● Rhizopus, Rhizomucor, Mucor, Absidia, Cunninghamella
ZYGOMYCOSIS or MUCORMYCOSIS
etiologic agents of zygomycosis
○ Rhizopus(R. oryzae)
○ Mucor
○ Absidia
○ Cunninghamella
hyphal structure that act like roots
Rhizoids
hyphal structure that act like connectors
Stolons
● Miscellaneous organism
● previously called Penicillium
● molluscumcontagiosum-like
○ acutaneousinfection
○ molluscumcontagiosum is a viral infection
● cutaneousulcers of extremities
TALAROMYCES
○ commonenvironmental flora
○ severalmanifestations
HYALOHYPHOMYCOSIS - Fusarium
● A lung infection
● Almost exclusively seen in individuals whose immune systems has been compromised by HIV or undergoing chemotherapy
PNEUMOCYSTOSIS
opportunistic atypical fungus causing pneumonia in
immunocompromised hosts
Pneumocystis jiroveci
treatment of pneumocystis
Trimethoprim-sulfamethoxazole
