Micro Mycology – Flashcards
Unlock all answers in this set
Unlock answersquestion
| define mycology |
answer
| study of fungi |
question
| what food is fungi |
answer
| mushrooms, soy sauce, tofu, cheeses, baking |
question
| what fungi are arguculturally significant |
answer
| mildew, rusts, blights, smuts, wilts |
question
| where do fungi infect |
answer
| skin, deep tissue, respiratory, opposrunists, CNS |
question
| how do fungi get food |
answer
| invate tissue and digest externally by releasing enzymes so it can get nutrients from surrounding host tissue |
question
| what is saporphytic, what organims are |
answer
| metabolic enzymes adapted to dead organic material fungi |
question
| examples of innate immunity the hinder fungi |
answer
| barriers, FA, mucocilliated cells, epithellial turn over, mucous membreans alternate mannose lectin binding complement pathway phagocyte response |
question
| what are three results of the complement pathway |
answer
| opsonins that promote phagocytosis neutrophil chemotaxis MAC attack |
question
| what fungal infections can result from phagocyte or neutropenia |
answer
| cryptococcus systemic infection canidia infection opportunists: aspergillus. fusarium, zygomycetes |
question
| what fungal infections can result from CD4 issue |
answer
| caniidia, cryptococcus, pnrumocytis systemic fungal infection opportunist infections |
question
| 3 components of fungi cell wall and their functions, what part is a drug target |
answer
| chitin: protection glucans: structure and energy storage mannoproteins: nutrient absorption and attachment chitin is a target |
question
| define plasmalemma, what are the components, what is a drug target |
answer
| plasma membrane below fungal cell wall rich in ergosterol which is a drug target |
question
| what is a polysaccharide capsule, where is it found, what is the function, give an example organism |
answer
| around some fungi, prevents phagocytosis cryptococcus meoformans |
question
| what temp do fungi grow best at, at what point will growth be stopped, what is the exception |
answer
| 25-30 deg C 37 deg C inhibits yeast are less affected by high temp |
question
| what are the 6 configurations of hyphe and function of hyphe |
answer
| Large and protective Hyaline: clear Demitiaceous: brown or black Aseptate: no cross walls, in groups Septate: cross walls, single Mycelium: mass of hyphae |
question
| describe the nucleus and growth location of mold |
answer
| multinucleate, grow extracellularly |
question
| what is a sporangia |
answer
| sac with spores that come from asexual reproduction in molds |
question
| aspergillus: what type of organism, where is it found, who does it infect, why is it sacary |
answer
| all around opportunistic big: immune system cant kill well |
question
| what is conidia |
answer
| reproductive organ people inhale of aspergillus |
question
| yeast: describe nuclei, getowh patterns, who they infect |
answer
| mostly single celled, mononucleate, opportunistic not too virulent |
question
| what is a pseudohyphae |
answer
| bud that is still attached to a yeast |
question
| how does yeast reptoduce, where at, why can their location be bad for them why is it bad for the host |
answer
| reproduce by division or budding (blastoconidia) live in macrophages or neutrophils and multiply. neutrophils can kill yeasts too large to fit inside. in the host it can cause neutropenia and mucosal damage |
question
| what makes something a dimorphic fungi, what parameters |
answer
| form hyphae at enivornmental temp and yeast at body temp yeast 35-37 deg C and mold at 25 deg C |
question
| what is a free living fungi, what do they do, how |
answer
| cause disease when they make toxins or spores and people inhale them normal flora are fee living fungi that are only innocous if the body's defences are compormised |
question
| what is a reactional to inhaled sports |
answer
| hypersensitive pheumonitis |
question
| what is a mycoses, what are the different types |
answer
| infections superificial, cutaneous / dermatycosis, subcutaneous, systemic / deep |
question
| where are superificial mycoses, what type of organisms, how is it spread |
answer
| yeast and mold grow on stratum corneum (dead layer) of skin, hair, nails, mouth, vagina spread via person to person or animal contact |
question
| how do cutaneous / dermatycosis invade and cause symptoms |
answer
| mold invades deep epidermis, hair, and nails keritanesis and enzymes release to infect tissue raised inflammatory scaly areas of skin and broken hairs occur may deseminate in the immunocompormised |
question
| how is a cutaneous / dermatycosis aquired |
answer
| animal cntact, soil, human contact |
question
| what are 6 examples of cutaneous mycoses |
answer
| ringworn tichophyton microsporum epidermophyton floccosum tinea ________ tinea versicolor |
question
| where does trichophyton infect |
answer
| hair skin nails |
question
| where does microsporum infect |
answer
| hair, skin |
question
| where does epidermophyton floccosum infect |
answer
| skin and nails |
question
| list the different types of tinea 8 |
answer
| capitis, favus, corporis, curis, pedis, unguium/onchomycosis, canidia albicans, systemic |
question
| where is tenia capitis what does it look like |
answer
| head, mostly in kids, fungi in hair like follicles, breaking of hair |
question
| where is tenia corporis and cruris |
answer
| body and groin |
question
| where is tenia pedis, what does it cause |
answer
| feet, athletes foot |
question
| that tinea infects the nails |
answer
| unguium.onchomycosis |
question
| qhat tinea infects area aroun the nails |
answer
| canidia albicans |
question
| what are the treatments for tinea infections |
answer
| topical: kentoconazole, clotrimazole, miconazole oral: griseofulvin, terbinafine, fibroquinolones |
question
| how doesmiconazole work |
answer
| attacks aldosterol which is involved in fungi choleserol membrane synthesis |
question
| who isnt fibroquinolones used much for fungus |
answer
| it can caus neurological effects |
question
| tinea versicolor: aka, location, presentation, MOA, what population is at risk |
answer
| pityriasis versicolor or normal flora malassezia furfur in active sebaceous glands so more freqnent in summer in ages 15-24 scaly waxy macular lesions hypopigmented via interference with tyrosinases dissemiination in immunodeficient and infants on liquid therapy |
question
| subcutaneous infections: type of organisms, where it infects |
answer
| yeast or mold nails, dermis, tissue, muscle, subcutis |
question
| subcutaneous infection example organisms 2 |
answer
| mycetome, sporotrichosis |
question
| mycetome: cause, location, signs, prognosis |
answer
| caused by thorn or tools localized and spreads to surrounding tissue causing deformit, enlargement, sinus tracts, tumors exudate with colored granules if untreated there will be extensive damager |
question
| rose picker's disease: aka, how aquiredm outcome |
answer
| puncture from rose thorn introduces sphangum moss, progressive edudate lesion along lymphatics, joint infection causes osteoperosis if inhaled it can become systemic in immunocompormised |
question
| what fungi does sphangum moss introduce |
answer
| sporothrix schenkil |
question
| deep mycoses: location, organisms, pathway |
answer
| disseminates to skin, organs, bone, CNS classig or dimorphic yeast or mold can infect people with normal immunity begin in lungs and disseminate via macrophage or blood |
question
| what conditions woould make someone immunocompormised |
answer
| ? Diabetic, chemotherapy, AIDS, immunosuppression ? Broad spectrum antibiotics ? Central venous catheter ? Malnutrition ? Immunodeficiency: genetic CGD, AIDS, immunosuppression ? Iatrogenic induced neutropenia (cancer, leukemia, chemotherapy, marrow, stem cell, solid organ transplant) ? Central venous catheter/parenteral nutrition ? Malnutrition ? ICU stay (IV) |
question
| list 13 systemic fungi |
answer
| Blastomyces dermatitidis Coccidioides immitis Histoplasma capsulatum Paracoccidioides brasiliensis Aporothrix schenkii – inhaled Conidia canidia cryptococcus neorformas c. gattii pneumocystis jurovecii sacharomyces cervisiae rhodotorula spp trichosporn beigelii |
question
| conidia infection process |
answer
| ? Microconidia or arthrospiores initiate inflammatory response via neutrophils and macrophages ? In tissue conversion to yeast or spherule stage virulence factors may suppress immune response ? Yeast go to hilar lymph nodes via macrophage initiating CMI and causing containment in the lower respiratory tract • If not contained severe pulmonary disease or dissemination (organs, bones, CNS, skin) |
question
| canidia infection process |
answer
| • Endogenous and exogenous (in health care workers and visitors) • Often enter the body via intravenous lines • Part of normal flora, opportunistic infector of immune compromised • dimorphic |
question
| canidia: yeast or mold, give three specific tpes |
answer
| both, dimorphic c. albicans, c. spp. canidia mycosis |
question
| where does c. albicans infect |
answer
| NF, oral, Gi, GU |
question
| where does canidia sp infect |
answer
| NF, oral, GI, GU neutropenic opportunist |
question
| canidia spp symptoms and why for each |
answer
| Thrush: Low pH, neduced NP. Due to CD4 loss (early AIDs symptpm) Vaginitis: immunosupression, diabetes, hormonal replacement therapy, pregnancy yeast in urine: due to antibiotic or renal disease yeast in nails, skin, mucosa: in eldery, malnourished, a biotin deficiency how it disseminates: neutropenia, chemotherapy, AIDs, peritoneal dialysis, catheter |
question
| canidia mycosiscauses |
answer
| T cell deficit due to chronic mucocutaneous infection |
question
| cryptococcus neofromans and C. gattii: best living conditions, locations, infection sites |
answer
| live in mucoid colonies at 37 deg C in dust, church steeples, barns infect via respiratory usually like to infect immunosupressed with T cell disorders |
question
| what does cryptococcus neoformins do to the body |
answer
| urease affects lysosomal function |
question
| how can cryptococcus neoformins be visualize |
answer
| india ink |
question
| pneumocystis jurovecii: how aquired, who infected, symptoms |
answer
| endogenous noral flora with airborne transmission effects immunocompormized mycoplasma like pneumonia, ground glass x-ray |
question
| pneymocystis jurovecii lab conformations staiin with |
answer
| ? Gomori’s silver stain ? Toluidine blue ? Weight giemsa |
question
| pneymocystis jurovecii tx and their MOA |
answer
| ? SXT – trimethoprim sulfamthoxaxole: bactrum, spectra, folic acid synthesis. antimetabolite ? Pentamindine: antiparasite that blocks oxidative phsophorlyation and RNA/DNA synthesis. Used for prophylaxis |
question
| what are the two sources of infection, give some fungi examples for each |
answer
| endogenous; opportunists canidia, pneumocystis, malassezia exogenous: enivornmental opportunists rhizopus, aspergillus, cryptococcus neoformans, gatti, penicillum |
question
| what are the two types of pathoges, where are they found, give some examples for each |
answer
| primary pathogens are systemic fungi in soil or aerosol: coccidoides immitis, histoplasma capsulatum, blastomyces dermatitidis, paracoccidioides brasiliensis secondary pathogen from animal or ennivornment: opportunists come in through skin break, superificial skin infection, dermatphytes, subcutaneous trauma |
question
| 10 virulence factors of fungi |
answer
| • growth at physiological pH and temp • polysaccharide capsules (Cryptococcus) • hyphae: large and protective • yeast to hyphal form (canidia albicans) • survival in phagocytes • secretion of invasive enzymes • flabohemoglobin • inflammation • promote factor H and I and interfere with CMI • mycotoxins |
question
| how can fungi survive phagocytosis |
answer
| conidial coat urease effects phagolysosome formation |
question
| what enzymes do fungi release. what do they do |
answer
| proteases to invade tissue phospholipases to damage host membranes |
question
| what is flabohemoglobin |
answer
| fungi product that interferes with NO formation in phagoytes |
question
| how do fungi cause inflammation |
answer
| granulomatous via monocytes, lymphocytes in subctaneous and systemic areas |
question
| what can fungi do that create conditions like in pertomatous leprosy |
answer
| promote H and I factor interfering with CMI |
question
| what are mycotoxins, give an example |
answer
| endotoxin ike activity from fungi alfatoxin: liver cancer |
question
| how do echinocandins work, on what organisms |
answer
| Inhibit glucan synthesis in fungal cell wall exposing the plasma membrane Fungicidal for canidia albicans, some are resistant (Fluconazole resistant candida albicans) Fungitatuc for aspergillus |
question
| how does griesofulvin work, on what organisms |
answer
| o Inhibits microtubule formation affecting mitosis o Used for dermatophytes |
question
| how does polyenesmystatin and ampoitericin B work |
answer
| o Selectively bind to ergosterol in the fungal membrane |
question
| how to azoles and allylamins work |
answer
| inhibit egosterol synthesis |
question
| how do pyrimidines work |
answer
| inhibit nucleic acid synthesis |
question
| what general form of drugs offer better delivery and fever sideeffects when treating fungi |
answer
| lysosomal forms of drugs |
question
| list the mold exogenous opportunistis, which are associated with fungal infection |
answer
| o aspergillus spp.: most commonly associated with fungal infection o Zygomycetes: rhizopus, mucor: most commonly associated with fungal infection o Fusarium o Bipolaris o Acremonium o Penicillium spp. o P. marneffi |
question
| how is a hiar specicime collected, what organisms might you find |
answer
| o Collect if broken or scaley or wood’s lamp o Dermatophytes: tenia capitis, tinea favus |
question
| how is a skin specimine collected, what might you find |
answer
| o Woods lamp superificial (tinea versicolor) o Scraping: superificial dermatophytes o Edudate: subcutaneous |
question
| how are respiratory specimines collected, what might you find |
answer
| o Sputum, BAL systemic, pneumocystis |
question
| what is a collected in a tissue biopsy how is it done |
answer
| o Disseminated subcutaneous o Mince and plate for culture then use histology to fix and stain |
question
| what fungi might be found in a blood culture |
answer
| o Fungemia yeast |
question
| how can CSF yeasts be found |
answer
| micropole filter |
question
| what are some direct examination methods |
answer
| o Saline: vaginitis, thrush for yeast o Skin and nails check for hyphae ? 10% KOH dissolves keratin ? Stains calcofluor white o India ink |
question
| how does inidia work, what does it show |
answer
| ? Shows cryptococcus neoformans in CSF ? Slows polysaccharide capsule and budding yeast in the middle ? Not a stain, light provides shadowing |
question
| what are three ways to do a microscopic examination, what do they show |
answer
| Biopsy tissue stains: Periodic acid Schiff, Hematoxylin and eosin. Methenamine silver Gram stain: For urine, sputim. Shows some yeast (canidia albicans) Giemsa: Peripherial blood stain. Shows histoplasma capsulatum |
question
| primary culture media: give four types and their composition |
answer
| ? Different from bacterial media ? SDA: cyclosporine, gent, chloramphenicol ? BHI with C and C or blood ? Neiger seed (caffeic acid) ? Dermatophyte test medium (DTM) |
question
| subculture media composition |
answer
| bichemical,pigment, spores potato destrose agar or corn meal agar |
question
| how are molds examined |
answer
| under a hood |
question
| what variables do you observe when examining fungi |
answer
| growth rate temp texture or topography pigment on each surface |
