Exam 3 Flashcards
what percent of known fungi are pathogenic?
in what do they cause disease?
30%
plants and humans
What is mycology?
What kind of cell are they?
the study of fungi
eukaryotes
What are the two types of fungi?
yeast and mold
How are fungi different than bacteria?
larger, grow slower, and at lower temperature
what are the 3 different roles of fungi?
- decomposers/recylers
- produce enzymes that we use (beano)
- produce medications (penicillin)
How would yeast be described? shape? reproduce? appearance? examples?
unicellular and non-filamentous
- oval
- asexually by budding
- moist, creamy, and white
- saccharomyes cerivisae and Candida albicans
How would mold be described?
filaments called?
what is mycelium?
reproduces?
multi-cellular and filamentous
- hyphae
- a mass of intertwined hyphae
- asexually via spores which can be inhaled by humans as a means of disease transmission
what is mycoses?
why do we not know how many mycoses cases we have?
how would mycoses happen?
what conditions aid this process?
- fungal disease
- not reportable to the CDC
- fungal pathogens are opportunists
- invasive medical procedures, medical therapy, pre-existing conditions, and life style factors
What are the three classes of drugs used to treat fungal infections?
polyenes, azoles, and echinocandins
How do polyenes work?
what are the two most commonly used? and how do they work?
- by attaching to the sterol component found in the fungal membrane, causing the cells to become porous and DIE
- nystatin-used as a topical agent to treat superficial infections, or orally to treat candidal infections
- amphotericin B- used to treat severe systemic fungal infections
How do azoles work?
what are the 3 common ones used? what are they effective against?
- by preventing fungi from making an essential part of their cell wall.
- ketocanazole-oldest, slightly more toxic, not very effective against aspergillosis or others
- flucanozole-against superficial and systemic candidiasis, but many are resistant to it now
- itraconazole-newest, effective against a range of different fungal infections , can treat aspergillosis
how to echinocandins work?
what are the 2 kinds and what are they effective against?
- disrupting the wall that surrounds fungal cells
- caspofungin and micafungin effective for sever systemic fungal infections
what is the disease and organism that causes fever, cough, chest pain, chills, night sweats, headache, fatigue, shortness of breath, joint aches, rash 1-3 WEEKS after exposure? how is it transmitted? where is it commonly found? how is at higher risk?
- Coccidoiomycosis (valley fever), Coccidioides immitus (mold), pathogen
- spores inhaled from disrupted soil, usually after natural disaster
- southwestern u.s. mexico
- consruction or farm or mine workers
what disease and organism causes fever, headache, dry cough, chills, chest pain, weight loss, night sweats, 3-17 DAYS after exposure?
how is it transmitted?
where is it commonly found?
who is at higher risk?
- histoplasmosis, Histoplasma capsulatum (mold, pathogen)
- spores in soil with bat or bird droppings, disturbed soil makes spores airborne and inhaled
- ohio, missouri, mississippi river valleys
- infant, young children, older people
what disease and organism causes thick, white, lacey patches in the MOUTH, red, flat rash with scalloped edges on the SKIN, and a thrush extending down ESOPHOGUS into stomach, painful ulcers, difficulty swallowing, and a whit, cheesy discharge, itching and burnign in the VAGINA?
how is it transmitted?
who is at greater risk?
candidiasis, Candida albicans (yeast, opportunist)
- part of NORMAL FLORA, change in environment causes imbalance and overgrowth of candida
- newborns, immunocompromised people, and common at least once in most women.
what disease and organism causes BLURRED VISION, bone pain, hest pain dr cough, fever, fatigue, headache nausea, night sweats, weight loss, weakness, PNEUMONIA-LIKE ILLNESS, shortness of breath, coughing,fever, skin lesions, and MAY INFECT CENTRAL NERVOUS SYSTEM?
- how is it transmitted?
- who is at greater risk?
Cryptococcosis, cryptococcus neoformans (yeast, opportunist)
- inhaled spores from environment where soil has bird (PIGEONS) droppings in it
- immunocompromised people (AIDS)
what disease and organism cause fever, rapid breathing, chills sweats, progressive, profound fatigue?
how is it transmitted?
who is at risk and who is not?
Pneumocystis pneumonia, Pneumocystis jiroveci (mold, opportunist)
- spores common in the environment inhaled
- immunocompromised (AIDS) people, DOES NOT CAUSE INFECTION IN HEALTHY PEOPLE
what disease and organism causes TINEA CAPTIS (round, scaly lesions on SCALP, hair loss), TINEA CORPORIS (round, scaly red lesions on the BODY), TINEA BARBAE (swelling and crusting around hair follicle in BEARD area, TINEA CRURIS (reddish, brown color in GROIN extends to thigh), TINEA UNGUIUM (yellow, think, crumbly toe NAILS), and TINEA PEDIS (scaling and inflammation of toe webs, thick scaling on heels, and soles, FEET)? (RINGWORM)
-how is it transmitted?
Dermatophytosis, Trichophyton OR Microsporum (mold, opportunist)
-direct contact with infected lesions or indirectly through contact with fomites on shoes, towels, showers, etc. COLONIZES ONLY DEAD TISSUE
what disease and organism causes brown/reddish/white patches on skin?
what disease causes patchy scaling or thick crust on scal;, yello/white scales (DANDRUFF) itching
how is it transmitted?
what are factors that encourage this?
Tinea Versicolor, Malassizia (yeast, opportunist)
Seorrheic dermatitis, same organism as above
-normally on skin of humans, but will overgrow
-humidity, sweating, oily skin
how are infectious diseases preventable?
vaccines
why are developing countries at a greater risk for infectious disease?
they face poverty, overcrowding, poor/lack of nutrition, lack of access o health care, chronic disease left untreated.
define infection
disease
can you have infection with out disease?
- invasion or colonization of the boy by a pathogenic microbe
- any change from a state of health
- yes
define acute disease and give example chronic disease latent disease communicalbe disease contagious disease non-communicable disease
- develops rapidly and lasts short time (cold)
- develops slowly and is continual (hep C)
- pathogen remains inactive and possibly reactive (herpes)
- disease that is spread from one host to another (flu)
- disease that is very EASILY spread from one host to another (measles, chicken pox)
- disease that can’t spread from one host to another (heart disease, diabetes)
define epidemiology
incidence
prevelance
- study of where and when diseases occur
- # of NEW cases of a disease in a given population or area
- total # of cases of disease ina given population or area (existing cases + new cases)