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62 Cards in this Set
- Front
- Back
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what are the 3 important groups of fungi |
1. yeast
2. Mold** focus here 3. Mushroom, wont get into |
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what are 2 mycotoxicoses
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1. Aflotoxins, mycotoxin made from Aspergillus flavus and other molds
2. Ergot Alkaloids |
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ok so what are the medically important things that mycoorginsms produce
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1. Yeast Mold- infections (most are in immunosuppressed 2nd infections. yeast grows fast, mold takes awhile)
2. Mycotoxicoses- food toxins 3. Allergies (primary pathogens, make AB) |
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what are the 1 and 2 infectinos asociated with fungi
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1- allergies, make AB
2- opprotunistic |
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who is likely to get a secondary fungal infectin
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secondary= opprotunistic
Immunocomprimised 1. Cacner tx 2. transplant (immunosuppression drugs) 3. DM 4. AIDS 5. Autoimmune (SLE, arthritis) |
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what are some risk factors for developing fungal infectino
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1. broad apectrum AB
2. radiation 3. chemo 4. corticosteroids 5. surgery 6. catherterization 7. hormonal, increased candida in menstrual cycle |
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talk to me about candida symbionts
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Normal flora, get colonized after birth
can grow with poor fitting dental device normal flora bacteria will inhibit candida infections (this is why broad spectrum AB are bad) called thrush when you have opprotunistis infaction (cheilitis also) |
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what causes thrush, what other disease
what causes dandruff what is a 1 infection |
Candida albicans
Pityrosporum Coccidioes immitis "coccioidomycosis", live in soil, can grow in nose |
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if an AIDS pt comes in and has a crusty rash on the corners of lips what is it likely to be? who else might present with a simliar finding more limited to the oral cavity
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chelitis and oral candida (tx with cancainazole OTC)
*caused by Candida albicans A baby can get oral thrush, tx moms nipples too (babes nutrition decreases) |
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Fungal Structure
1. pro or eukaryotic 2. chlorophyll 3. cell membrane 4. Cell wall |
1. Eukaryotes, like us - implicatins for killing
2. NOPE, it like us, not a plant 3. Made og Ergosterol/zymosterol - good thing to take advantage of amphotericin B 4. Cell Wall, ok so maybe a little like a plant... Rigid, Chitin, b glucan, mannan. NO peptidoglycan like bacteria have (Caspofungin inhibits glucan and is used for candida and aspergillus infection) |
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ok so a fungus is a eukaryote so its similar to us, in what ways can we tell the difference btwn us based on cell wall
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Cell Membrane: NO cholesterol, has ergosterol, target for AB tx (amphotericin B)
Cell Wall: we dont ahve one!! rigid, make of chitin, b glucan and mannan (no peptidoglycan as was seen in bacteria) |
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what is thermal dimorphic conversion
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fungi grow in dif phases at dif temps
Yeast: 37 (in us) budding Mold 25 (fridge) filamentous multicellular body |
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whats the dif btwn a yeast and a mold
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nothing, they are the same thing they just have thermal diphasic conversion
Yeast 37 (us) budding. grows fast in lab Mold 25 (fridge) filamentous multicellular body. takes weeks to grow in lab |
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yeast are eukaryotes how can we tell them apart form us at micro?
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yeast bud
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who has pseudo hyphea and germ tubes
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yeast, also bud for reproduction
**keep in mind it will look WAY bigger than a bacterium |
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whats a germ tube
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looks like a handle growing from a yeast, virulence factor that allows adhesion/invasion
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whats histoplasma capsulatum, what will it look like
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yeast: budding, germ tube, pseudohyphea
1 pathogen common in the midwest |
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whats unique about cryptococcus
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encapsulated yeast
oval cell that buds and has pseudohyphea and germ tumes (adhesion/invasion virulence)' causes oral infection in HIV pts, get ulcerations |
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ok so we are looking at a smaple and we see oval cells that are budding (we are pretty sure they adhered to the host bc of this handle looking thing) but we also see this filamentous looking elongated structure that kinda looks like hair! is our sample contaminated
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nope, its just pseudohypha- elongated yeast cells
**conversion of candida to help it adhere (besides germ tube) |
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whats the elongated appendage that grows from a yeast cell? fx
whats the elongated yeast cell? fx |
1. Germ Tube: VIRULENCE to let candida adhere. it makes proteolytic enzymes and actually penetrate the tissue
2. Pheudohypha: conversion candida goes through so it can adhere to tissue more easily |
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what lets a yeast adhere and penetrate tissue
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germ tube
candida |
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at what temp might we see a milticellular filamentous colony
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25* mold, look fuzzy. takes a long time to grow in lab
NEVER SNIFF THEM, they have spores you can breath in!!! no matter how cool and colorful they are NEVER breath them!!! |
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why would it make more sense to incubate a fungus at warmer temps, not they this is how its done...
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bc at warmer temps they are yeast and not molds. molds have spores that can be inhaled, not good!!!
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is this a yeast or mold structure
mycelium hypha pheudohypha septum sporangiophore sporangium sporangiospore germ tube conidiophore conidia |
mycelium- mat of hyphae
hypha- long strand/filament of cells (can be septate: aspergillus, or nonseptate: rhizopus, mucor) pheudohypha YEAST septum sporangiophore- balloon with spores in it, the balloon is on a string of course sporangium ball of sporangiospores sporangiospore- single strucute, found within a sporangium germ tube YEAST conidiophore- hyphea branch with conidia at the end conidia- cluster (not a sac) of spores **all others are mold |
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what is a long strand or filament of cells called. what are the 2 types, what are examples
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hypha- MOLD
Can be septate: aspergillus can be non septate: rhizopus, mucor |
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whats mucelium
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mat of hypha
hypha is a long strand or filament, associated with MOLD |
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an imperfect fungi means what
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its asexual
perfect are sexual, asexual are more common |
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whats a...
sporangiophore sporangium sporangiospore asexual (imperfect) spores |
sporangiophore- stalk that holds spornagium (this stalk comes off of the hypha)
sproangium- balloon full of spronagiospores, on the end of the sporangiophore stalk sporangiospore- the individule little spore that is held in the balloon sac called the sporangium |
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whats the stalk that holds the ballon called
whats the balloon called what inside the balloon |
sporangiophore- this comes off the hypha
sporangium sporangiospore |
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ok so a sac of spores is called a sporangium, what it is called if its more of a cluster
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conidium- also an asexual (imperfect spore)
**individually positioned **used to determine what bug **there is a hypha that has a condidiophore, the condidiophore holds the conidium |
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what holds the condidium
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condidiophore
fungal structure- hypha with a condidiophore that comes off there is there a small little connection called the philalide that connects the condidiophore and hte conditium. there is no sac to hold all of the condidium in. its just like a cluster ex penecillin and aspergillus (aspergillus have septate hypa) |
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what are 2 fungi that have condidium
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penecillium
aspergillus hypha- condidiophore - philalide- condidium |
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what is...
1. Arthrocondidium 2. Blastocondidium 3. Chalmydocondidium |
1. Arthrocondidium- hypha fragmenting. there is an empty space btween blocks, looks like a tennis bracelet (dis jointed, arthro means joint)
2. Blastocondidium- budding 3. Chlamydoconidium- swollen hypha, seen in blastomyces |
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- conidium means what
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spore
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all dif spores, we know conidium means spore
what spore is disjointed and looks like a tennis bracelet what is a budding spore what is a swollen hypha spore |
arthrocondidium
blastocondidium chlamydoconidium- blastomyces |
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whats a unicellular conidial spore
what about multicellular |
microcondidium, trichophyton (ring work)
macrocondidium, ex microsporium (fisiform banana shape) |
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wht kind of spore is unicellular, whats an example
what kind is multicellualr, what does it look like, what is an example |
Unicellular: microcondidium, ex ring worm (trichophyton)
Multicellular: macroconidium (bananna shape) ex microsporum |
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what does it mean microsporum, macrodondidia
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condidia is the spore so we know its a multicellular spore
*microsporum is an example of a fungus with a multicellular spore (its banana shape) |
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A patient who is being treated for a malignancy
develops sores of the mouth and lips. Lab culture produces microscopic cells with germ tube What is the causative agent |
candida
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Tissue biopsy from a patient w/ diabetic
ketoacidosis reveals nonseptate hyphae. The most likely agent is |
rhizopus or mucor
sepetate hypha are aspergillus (they also have the cluster type condidium, no sac) |
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Tissue from a skin scraping, cleared in 10%
KOH, reveals fungal structures that are like blocks with some space btwn them What are these structure |
arthrospores
Germ Tube: virulence for candida, like a handle Blastospore: budding spore Pseudohyphae: structure on yeast, elongated yeast cell CHlamydospore- swollen hypha |
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what are 3 kidns of pathogenesis of fungi
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1. Granuloma formation- abcess, necrosis
2. Hypersensitivity reactions- allergic pneumonitis 3. Mycotoxicoses- intoxication and tissue damage (we dont really cover this) |
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what are mycoses, what are the types
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mycoses, fungal disease
1. Systemic/endemic- coccidiomycoses 2. Superfucial: thrush, dermatophytes 3. Subcutaneous/Dermato: sporotrichosis, mycetoma , ring work (trichophyton, microcondidia-unicellular)) 4. Opprotunistic: candida, cryptococcosis |
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types of mycoses
1. what are the systemic/endemic 2. Superficial 3. Subcutaneous 4. Opprotunistic |
1. coccidiomycoses
2. thrush, dermatophytes 3. sporotrichosis, mycetoma 4. candida, cryptococcosis (mucor, apergillis) |
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whats coccidiodomycosis
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systemic mycoses,
creates granulomas |
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atheltes foot it waht
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superficial fungal infeciton
sporotrichosis mycetoma trichophyton madura- big nasty foot, squeeze it and lots of fungus comes out, lots of hypha |
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what toxigenic virulence factors are associated with a mycosis
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NONE!!!! no endo or exotoxins are assoiated with mycosis
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what endo/.exotoxin is associated with mysosis
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NONE!!! no toxigenic virulence factors with mycosis (fungal infection)
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ok so lets talk superficial candidiasis
when do we see... 1. mucosal 2. skin 3. nails 4. systemic |
1. Mucosal: oral/vaginal associated with immunosuppression. baby, AIDS, contraceptives, AB use
2. Skin infections in old and obese 3. candida infections in nails is called candidal paronychia 4. systemic: URI, UTI, candidemia |
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1. if you have aids, are a baby or are taking contraceptives what tpye of superficail candida are you prone to
2. if you are old or obese what kind of candida are you prone to 3. if you have candidia in your nails what is it 4. if you have systemic candidia how might you manifest |
oral or vaginal
2. superficial skin infections 3. candidal paronychia, localized inflammaiton (onychomycosis) 4. still considered superficial candidiasis- respiratory, UTI, candidemia **RECALL- germ tubes will be present in ALL |
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how does candida invade
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germ tubes
pseudohyphae |
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what things make candida more virulent
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remember there are no endo/exotoxins
1. Germ tubes: invasion 2. adheres well to tissue/prosthetics- biofilm 3. extracellular enzymed: phospholipase, proteinase, haemolysin. 4. things we do like not brust teeth (let biofilm build up) or have bad dentures. 5. disturb normal flora: AB, DM, corticosteroids, poor diet, old, radiation, |
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what fungus has lots of enzymes to help break tissure down, how can it invade tissue
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candidia, uses thses enzymes, germ tubes and pseudohypha
**can also adhere really well to things so we get a biofilm. ill fitting appliances and poor hygiene speed process |
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what is an ENCAPSULATED pathogen
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cryptococcosis
the capsule makes it resistant to host defense can see oral infections in HIV pts |
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Some factors predisposing the patient to oral candidiasis include
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chronic local irritant
1. ill-fitting appliance 2. inadequate care of the appliance 3. disturbed oral microbiota because of -antibiotic or corticosteroid use -poor diet -diabetes mellitus -malignancy -blood dyscrasias - radiation therapy - advanced age, -hospitalization, -oral epithelial dysplasia -heavy smoking |
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who gets an infection by an encapsulated fungus, what does it look like. whats the fungus
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cryptococcosis
oral infections/ulcerations in HIV pts |
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what do we need to know about fungi for the lab
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1. Aerobic
2. need a transport medium- call lab 3. DONT INHALE SPORES 4. molds get a special cabinent, they grow slow at lower temps a 5. yeasts grow fast at warmer temps |
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what media are fungi grown on
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1. Sabouraud agar
2. Potato dextrose yeast grow fast mold talke long adn need special area bc of spored can be inhaled this media WONT support bacterial growth |
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how are yeasts ID in lab
how are molds ID in lab |
yeast: biochemical (aerobic metabolis, fermentation,)
mold: structure |
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how do you visualize a fungus skin scraping sample. what might you scrape
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gram stain, chlorazol black (india ink and KOH)
arthroconidia in ringworm, spherules in coccidioidomycosis |
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when might you visualize a tissue sample at histo for ID
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when it invades tissue
cocci |
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A med tech who routinely isolates fungi in the
lab develops a severe fungal pneumonia. How did the tech most likely become infected 1. Sitting on a toilet seat at a Texaco station 2 Eating a fast food undercooked hamburger 3 Not properly washing the hands 4 Fecal contamination of drinking water 5 Inhalation of conidia |
INHALATION
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