Fungal Respiratory Infections Flashcards
What are the 3 systemic mycoses?
Histoplasma Capsulatum, Bastomycetes Dermatidis, Coccidiodes Immitis
What are the 3 opportunistic mycoses?
Aspergillus spp., Zygomycetes (Mycormycosis), Pneumocystis Jerovici
Are the systemic mycoses dimorphic?
Yes
What is the reason that dimorphic fungi are resistant to phagocytic killing?
The tissue form, not the environmental form (mold) is invasive and resistant
What is the distinct form of conida that Histoplasma form?
Tuberculate (bumpy)
Where is Histoplasma found and in what form?
It is found as mold in soul with bird/bat excrement; OH + MS River Valley and Central America
What does the Histoplasma yeast target in the human body?
The RES System (Lymph nodes, bone marrow, spleen)
What disease does H. Capsulatum cause?
Histoplasmosis
What is the damage from fungal infections caused by?
Our immune system response to phago-resistant fungi
What are the symptoms of Histoplasmosis?
None > mild flu > pneumonia
What patients have an increased risk of contracting Histoplasmosis?
ICP’s
What is the difference between B. Dermatitis and H. Capsulatum in terms of where they can survive?
B. Dermatitis cannot survive in macrophages when in the yeast form
Where is B. Dermatitis found?
In the soil of the Mid-South, SE, and Mid-West
Who is most commonly infected with B. Dermatitis?
Middle aged to older men
What disease does B. Dermatitis cause?
Blastomycosis
What symptoms does Blastomycosis cause?
Acute Pneumo (Brown, purulent/bloody sputum) and wart-like skin lesions > meningitis
What does Blastomycosis look like? Hint: Lung masses develop
TB/Cancer
What form does Coccidiodes Immitis take in its tissue form?
Spherules
Because it is highly infective, C. immitis is considered a what?
Bioweapon
Where is C. Immitis found?
The semi-arid climates of SW US
What disease does C. Immitis cause?
Coccidiodomycosis (Valley fever - San Joaquin, CA)
What symptoms does C. Immitis cause?
None > flu > Skin lesions > mengitis
Who is most likely to get Coccidiodomycosis?
Men, dark skinned, ICP’s (increased for dissemination)
What are the treatments for Systemic Mycoses?
If healthy: Observe for 1 mo., if infection after 1 mo = 6-12 wks azole
If chronic/systemic = Amp B for wks > Azole for 1-2 yrs
If ICP = Abp b for wks > Azole for rest of life
What form does Aspergillus spp. form and where is it found?
45 degree branching septate hyphae; It is a nosocomial infection so it is found in hospital air ducts (ICP’s)
What disease does A. spp. cause?
Aspergillosis
What symptoms will a patient with Aspergillosis exhibit?
Previous respiratory disorders; an aspergilloma @ pre-existing lesion
What form does Zygomycetes (Mucormycoses) take?
90 degree broad nonseptate hyphae
Under what conditions are Zygomycetes found?
After an increase in soil disturbance; think tornadoes
What disease does Zygomycetes cause?
Mucormycosis/zygomycosis
What are the symptoms of Mucormycosis?
Acidosis (diabetes pts) or corticosteroid pts; presents as pneumonia or rhinocerebral form (rapid death)
What form does P. Jerovici take?
Thin walled cysts that contain sporozoites; NO hyphae
What is special about the way P. Jerovici is cultured?
It cannot be cultured - both fungal and protozoal characteristics
What is the P. Jerovici membrane made of?
Cholesterol
What disease does P. Jerovici cause?
Pneumocystis pneumonia (PcP)
What does pneumocystis pneumonia look like? What causes death?
Like diffuse interstitial pneumonia; asphyxiation
What is the treatment for the Opportunistic fungi?
Asp./Zyg: = Amp B + Excision Pneumo = O2 + Trimethorpim-sulfa-methoxazole
What does KOH stain for fungals?
Ergesterol
AIDS is the most common predisposing condition to PcP, what therapy has reduced the incidence of PcP in the AIDS population?
HAART therapy
Cultures must be grown from what for Aspergillosis?
Brochoalveolar Lavage (BAL)
