Unit 4 Part 8: Introduction to fungi of medical importance Flashcards
is fungi usually considered more or less dangerous then bacteria and viruses
less
does fungi usually cause disease in healthy people
rarely
what is fungi commonly used in (3)
medicine
food and beverage production
biotechnology
what 2 conditions promote fungal growth
darkness and moisture
are fungi eukaryotes or prokaryotes
eukaryotes
what are single celled fungi called?
what are multi-cell fungi called
single celled: yeasts
multi-cell: molds
what term is given to pathogenic fungi that alter between both single and multi-cell forms
dimorphic fungi
dimoprhic fungi are considered
true pathogens
what dimorphic fungi causes histopalsmosis in humans
histoplasma capsulatum
what organ does histoplama usually invovle
lungs
where does histoplasma usually grow
as mold in the soil and yeast in animal and human hosts (temperatue dependent)
2 features of opportunistic fungi
low virulence
typically pathogenic to immunocompromised hosts
do dimorphic or opportunistic fungi usually have geographic distribution
dimorphic
what is the study of medical mycology
study of fungi that cuase human disease
what is another term of fungal diseases
mycoases
what is the classification of mycoses based on
level of tissue involvemnet
mechanism by which the fungi enter the body
what are the two sources of fungus
endogenous and exogenous
what is the classification of endogenous pathogens
opportunistic
what is the source of endogenous opportunistic fungal infections
latogenic (means medical treatment)
(e.g. indwelling lines, catheters, etc.)
exogenous fungal infections that can be classified as superficial, cutaneous or subcutaneous are usually caused by
trauma
exogenous fungal infections that are classified as systemic or opportunistic are often caused by
inhalation
superficial mycoses usually infects what area of the body
outermost layer of the skin and hair, they do not invade living tissues
what type of mycoses is tinea capitis
superficial mycoses
what is tinea capitis
syperficial mycoses
infection of the hair follicles on the scalp and eyebrows
what are the S&S of superficial mycoses
itching
redness
crusted lesions
scaly scalp
what is the MR of superficial mycoses
humans
what is the modes of transmission for superficial mycoses
sharing/contact with contaminated articles or self-infection
what’s another term for cutaneous mycoses
dermatophytoses
where do fungi colonize in cutaneous mycoses
skin, hair and nails
do cutaneous mycoses have greater invasive properties than those causeing superfical mycoses
yes
what are the S&S of cutaneous mycoses
itchy
red roudn or oval lesions/rash, which may peel off the edges around the center fading
what are 3 examples of cutaneous mycoses
ringworm
atlehtes foot
jock itch
what is the MR for cutaneous mycoses
humans
soil
animals
what is the MT for cutaneous mycoses
PTP via
contact such as the shower floor or sharing contaminated hat or towel
other than humans what else can transfer cutaneous mycoses to humans
animal
soil
for subcutaneous mycoses how do fungi surive in the subcutaneous layers
produce proteolytic enzymes and maintaing a facultative microaerophilic environment
what is an example of a subcutaneous mycoses
sporotrichosis
where do subcutaneous mycoses often infect
arms and hands
what are the S&S of subcutaneous mycoses
numerous nodules
abscesses
ulcerative lesions tha develop along the lympahtics
(original site drains into lymph nodes)
what is the MR for subcutaneous mycoses
soil and decaying vegetation
what is the MT for subcutaneous mycsoses
indirect transmission e.g. by punctures
fungi are said to be ________ in that they can obtain nutrietns from decomposing dead organic matter
saprophytes
systemic mycoses are caused by
disseminated fungal infections of deep tissues and/or organs
what are the most servious and potentially life-threatening type of mycoses for elderly and immunocompromised
systemic mycoses
where do systemic mycoses usually begin
infections of the respiratory tract
what is the MR for systemic mycoses
soil
birds and bats droppings increase nitrogen levels in soil that promote growth of theses fungi
what is the MT of systemic mycsoes
airborne inhalation of fungal spores
what is the causative agent of the systemic mycoses blastomycosis
blastomyces dermatitidis
what are the S & S of blastomycosis
flu-like symptoms that vary in degree dependent on how far it spreads
where does blastomycosis originate
in the lungs then spread to parts of the body usch as skin, bones, joints and the CNS
what is the IP for blastomycosis
30-45 days
what are they signs and symptoms of the systemic opportunistic mycoses pneumocystis pneumonia
fever mild/dry cough SOB fatigue weight loss Chest Pain
what is one of the most frequent and severe opportunistic systemic mycoses infections in the immunocompromised
pneumocystis pneumonia
what opportunistic mycoses is found in 70-80% of HIV+ patients
pneumocystis pneumonia
what is the MR and MT of pneumocysiti pneumonia
unknown believed to be spread by PTP via direct contact
what is the IP in pneumocystis pneumonia
3-12 weeks
what is the opportunisitc mycoses: candidiasis (thrush)
infections of the mucous membranes of oral caivity and genital tract - creamy white lesions
what is the causaitve agent of candidiasis
candida albicans
what is the major resevoir for thrush
humans, candida is part of our normal biota
what is the treatment for thrush
anti-fungal drugs such as nystatin mouthwash (oral thursh)
miconazole cream/suppository for Vaginal thrush
what does candida mean
white - white colonies and white lesions
what are risk factors for thrush
high estrogen levels
low progesterone levels
less competeion from mutualistic microbiota e.g broad spectrum antibiotics and chemo
diabetes
what is the symptoms of VVC (vaginal thrush)
extreme itch dysuria thick discharge vaginal discomfort soreness burning swelling
what is the discharge for vaginal thrush
cottage cheese
what are the symptoms of BV
odor itch discharge soreness bruning
what is the discharge for BV
thin,milky, fishy smelling
what are the symptoms for trichomoinaiasis (STI)
odor itch discharge soreness could be asymptomatic
what is the discharge for trichominasis
frothy gray
or yellow/green
foul odor
trichomoniasis clinical features
strawberry cervix
small red or purple spots from bleeding under the skin
swelling
out of VVC, BV and trichomoniasis which one results in a positive KOH “whiff” test
trichomoniasis
the opporunistic mycoses crytococcosis infects what
infection of lungs, meninges and/or skin
what is the causative agent of the opportunist mycoses cryptococcosis
cryptococcus neoformans (CN) & cryptococcus gatti (CG)
what is the MR for cryptococcosis
environment, particularly trees, decaying woods, soils and bird droppings
what is the MT for cryptococcosis
airborne/aerosols - inhalation of fungalspores
what are the S & S of cryptococcosis
prolonged cough SOB headace vomiting fever weight loss
cryptococcosis can lead to what
pneumonia or meningtisi
what are nosocomial mycoses
outbreaks of mycoses in health care settings: airborne and construction related: airborne and construction-related
what is the most common nosocomial mycoses
aspergilus aka “black mold”
what is mycotoxicoses
fungal disease caused by ingestion of fungal toxins (mycotoxins)
aflatoxins caused by aspergilus (black mold) can cause what
liver damage and cancer
what is sick building syndrome
a condition affecting office workers, typically marked by headaches and respiratory problems attributed to unhealthy or stressful factors in the working environment such as poor ventilation
what have been raised as possible causes of SBS
fungi and mycotoxins
what type of symptoms cause sick builiding syndrome
allergy-like syndrome
what are the toxic effects of aflatoxins
hepatotoxicity
bile duct hyperplasia
intestinal and renal hemorrhage
liver tumors
what are the two main mycotoxicoses causing agents
aflatoxins
trichothecenes
what are the toxic effects of trichotheceencenes
vomiting diarrhea bleeding dyspnea itching rash blisters leukopenia
what are type 1 HS
type 1 hypersensitivity
symptoms similar to hay fever and food allergy
what is type 3 HS
woodworkers lung due to repeated exposure to allergins in wood pulp and dust
what are the risk factors for allergy/hypersensitivity to fungi
genetic predisposition
excess humidity
tightly sealed and insulated homes
building leaks
lack of maintenance on air conditioners etc
occupation hazard e.g. those who work in the mill
