Exam 3 Flashcards
What antibiotics are produced by fungi?
- Penicillin (from Penicillium notatum)
- Streptomycin (from Streptomycin griseus)
What fungi produces blue cheese?
Penicillium rouqueforti
Two forms of fungi
- Microscopic yeasts
- Filamentous molds (i.e. moldy orange)
Are fungi prokaryotic or eucaryotic microbes?
Fungi are eucaryotic microbes
Are fungi unicellular or multicellular?
Fungi can be unicellular or multicellular
What is the mode of multiplication for fungi?
- Spore formation - spores can be inhaled or land on skin and cause infection
- Some fungi have complex life cycles (asexual/sexual)
How many species of fungi are there?
Over 50,000 species
How many species of fungi cause disease?
About 25
What fungi is the cause of “sick building syndrome”?
Stachybotrys chartarum
Who does “sick building syndrome” affect?
- Affects people who are allergy sensitive
- Immunosuppressed
What can Stachybotrys chartarum cause?
- Causes respiratory illness and sensitivities
- Rarely causes necrotizing soft tissue infections (causes by Mucormycetes)
When are two examples of when “sick building syndrome” has occurred?
- Joplin, Missouri tornado
- Hurricane Katrina
What is the pathogen that causes white-nose syndrome?
Pseudogymnoascus (Geomyces) destructans
Host of white-nose syndrome and effects
Host: bats
Causes:
- fungal grows on muzzle and wings
- skin erosion
- abnormal behavior
Two types of fungi found in the environment
- “sick building syndrome”
- white-nose syndrome
4 fungal disease groups
- deep mycoses
- superficial mycoses
- subcutaneous mycoses
- mucocutaneous mycoses
How are deep mycoses diseases acquired?
- inhalation of fungi or conidia (fungal spores)
- contaminated surgical equipment
What happens during deep mycoses diseases?
- lead to systemic or disseminated infections
- spread to skin
Who does deep mycoses diseases usually affect?
immunosuppressed
Where is Aspergillosis found?
indoors and outdoors
Risk factors for Aspergillosis
immunosuppressed (asthma, cystic fibrosis, bone marrow/organ transplant, chemo, HIV)
How common is Aspergillosis and what is the prognosis?
- Rare (not reportable)
- High mortality (~100%)
- Death in weeks
What can Aspergillosis cause?
acute pneumonia
symptoms of aspergillosis
- allergic bronchopulmonary signs (wheezing, coughing)
- invasive aspergillosis symptoms (fever, chest pains, coughing, SOB, aspergilloma (fungal ball) )
Aspergillosis dx.
- chest x-ray
- CT scan of lungs
- biopsies
Aspergillosis tx.
Antifungal medications:
- Amphotericin B
- Itraconazole
usually ineffective
pathogen that causes Blastomycosis
Blastomyces dermatitidis
where is Blastomyces dermatitidis found?
moist soil
Blastomycosis transmission
inhalation
where is Blastomycosis found?
- some states
- endemic in some areas
symptoms of Blastomycosis
- half are asymptomatic
- show up weeks to months are exposure
- flu-like
- rarely disseminates to skin and bones
Risk factors for Blastomycosis
- any healthy person or immunosuppressed
- endemic in U.S.
dx. and tx. of blastomycosis
Dx:
- culture
- antigen test
Tx:
- Itraconazole
cause of Candidiasis
yeasts (genus Candida) most common is Candida albicans
three forms of Candidiasis infection
- oral
- genital (vaginal yeast infection)
- invasive (bloodstream)
what is the source of infection in Candidiasis
imbalance of yeast
4th most common hospital-acquired blood stream infection
candidiasis
symptoms and diagnosis of oral candidiasis
Symptoms:
- redness and soreness
- difficulty swallowing
- cracking at corners of mouth
Diagnosis:
- scrape affected area -> microscope
symptoms and diagnosis of genital candidiasis
symptoms:
- itching
- burning
- “cottage cheese-like” discharge
- rash
diagnosis:
- sample of vaginal secretions -> microscope
symptoms and diagnosis of invasive candidiasis
symptoms:
- fever and chills
- non-specific
- symptoms do not improve with antibiotics
diagnosis:
- blood culture
risk and treatment for oral candidiasis
risk:
- HIV/AIDS patients
- cancer treatment
- organ transplant
- diabetes
- dentures
- broad-spectrum antibiotic use
treatment:
- good oral hygiene reduces risk
- itraconazole (oral antifungal medication)
- topical wash (clotrimazole troches)
risk and treatment for genital candidiasis
risk:
- pregnancy
- diabetes
- broad-spectrum antibiotic use
reduce risk by:
- wearing cotton underwear
- oral probiotics
treatment:
- over the counter suppositories/creams
risk and treatment for invasive candidiasis
risk:
- surgical patients
- ICU
- central venous catheter
- weakened immune systems
- low-birth-weight infants
reduce risk by:
- infection control practices with central line
treatment:
- oral/IV antifungal medication (amphotericin B, fluconazole, echinocandin)
first US case of drug-resistant fungal infection
Candida auris (2016)
In what states is Coccidioidomycosis endemic?
- Arizona
- California
- Nevada
- New Mexico
- Utah
Coccidioidomycosis
valley fever
In Phoenix, Coccidioidomycosis is the cause of 15-30% of what disease?
community acquired pneumonia
symptoms of Coccidioidomycosis
- 60% asymptomatic
- fatigue
- cough
- fever
- SOB
- headache
- sweats
- muscle aches
- rash on upper body
What microorganisms cause Cryptococcosis?
- Cryptococcus neoformans
- Cryptococcus gattii
Where is Cryptococcus neoformans found?
Found in soil worldwide and people inhale fungal spores
Risk factors for Coccidioidomycosis
- people who live or travel in southwestern states (Utah, Nevada, New Mexico, Arizona)
- adults >60 years
- weakened immune systems (HIV/AIDS, organ transplant, pregnant, diabetes, black or Filipino)
Diagnosis for Coccidioidomycosis
- medical and travel history
- blood sample looking for antigens
- occasionally chest x-ray and biopsy
Treatment for Coccidioidomycosis
- most symptoms go away within a few months without treatment
- sometimes antifungal meds are prescribed to reduce symptoms
Species that causes Coccidioidomycosis
Coccidioides species (C. immitis and C. posadasii)
How is Coccidioidomycosis acquired?
inhalation of fungal arthrospores that exist in soil of endemic areas
What was the epidemic of Coccidioidomycosis in Arizona in 2000 associated with?
Climatic changes
Incidence of C. neoformans
Very low (<1%)
C. neoformans is estimated to cause 1 million cases of ? per year among HIV/AIDS
Approximate number of deaths that occur and where
C. neoformans causes about 1 million cases of cryptococcal meningitis
About 600,000 deaths in Sub-Saharan Africa
Cryptococcosis is a reportable disease in which two states? How many infections have been documented between 2004-2011?
Oregon and Washington
100 infections
symptoms of Cryptococcosis (mild and severe)
- SOB
- cough
- fatigue
- fever
- HA
-
C. gatti and neoformans can infect the nervous system and cause inflammation of brain and meninges
- cause altered mental state and dissemination to lungs, skin, brain
- C. gatti symptoms begin 2-14 months after exposure
- C. neoformans can cause l_atent infection_ or symptomatic disease
- cause altered mental state and dissemination to lungs, skin, brain
Who is at risk for developing cryptococcosis?
immunosuppressed
Diagnosis of cryptococcosis
- microscopic examination and/or culture of tissue or fluids (blood, CSF, sputum)
- Culture dx cannot distinguish between the two different species
Treatment for Cryptococcosis
antifungal for at least 6 months
Dermatophytes
- Fungi that cause skin, hair, and nail infections
- other names: “Ringworm” or “Tinea”
Where do Dermatophytes live?
live in moist areas of skin, environment, material
Symptoms of Dermatophytes
- can affect skin on almost any area of the body
- infections are usually itchy, red, scaly, cracking of skin, ring-shaped rash
How common is ringworm?
very common, including healthy people (contact sports, baths)
Prevention of Dermatophytes
Good hygiene
Diagnosis of Dermatophytes
- most often based on symptoms
- sometimes scrape affected area and microscopy
Tx of Dermatophytes
- oral antifungal meds (some)
- topical (most)
symptoms of Histoplasmosis
- fever, cough, chills, headache, body aches
- symptoms appear a few days to a couple weeks after exposure
- usually go away within a few weeks to a month
