Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/48

Click to flip

48 Cards in this Set

  • Front
  • Back
Fungi:
Eukaryotic cells
Cell wall contains chitin and ______
glucan
Fungi:
Cell membrane contains _______ instead of cholesterol as in mammals
ergosterol
Endemic dimorphic fungi in US
(3)
Blastomyces dermatitidis
Coccidioides immitis
Histoplasma capsulatum
Opportunistic fungi (4)
Candida sp
Aspergillus sp
Mucor sp.
Pneumoncystis jiroveci
Dimorphic
Exist in 2 morphologically different forms:
1)? multicellular, thread-like hyphae found in environment (free-living phase)
2)? single cell form found in tissues (parasitic phase)
1)Molds-
2)Yeasts-
Histoplasma
Blastomyces
Paracoccidioides
Coccidioides
Penicillium
Mold and yeast forms:
A, B, C, D, E?
What Fungus?
Soil organism
Growth in soil enhanced by bird or bat guano (poop)
Specific types of environments
Caves
Chicken coops
Old buildings
Histoplasma capsulatum
Histoplasma capsulatum Endemic in parts of the central and eastern United States along _____________ river valleys.
Ohio and Mississippi




Microfoci in Central and South America, Africa, India, and Southeast Asia.
Histoplasma capsulatum:
Microconidia are inhaled
Transform into ______
yeasts
Histoplasma capsulatum:
Phagocytosed by macrophages but are not killed
Killing of intracellular yeast depends on Th1 cell activation of ________ through release of g-IFN
By this time, organisms have spread widely in lung
macrophages
Histoplasma capsulatum:
_________ form around infected macrophages
Later they calcify (can see this on CXR)
Organisms remain viable in granulomas for years
Can be reactivated if person becomes immune suppressed
Granulomas
Histoplama:
_____% of population living in endemic areas are skin-test positive.
80
miliary
Chest radiograph showing
__________ densities in both lung fields plus thin-walled cavity with fluid level. Histoplasmosis.
Diagnosis of histo
Culture of sputum or lung tissue
Histologic examination of biopsied lung tissue shows yeast within macrophages
Treatment of histo
Severe infections- amphotericin B
Mild to moderate infections- itraconazole
What fungus?
Soil organism
Found in decaying leaf litter
Found in southern and mid-western US
Infection follows inhalation of conidia
Blastomyces dermatitidis

Blastomycosis
Organism can enter blood and go to skin to form lesions
Blastomycosis
?
Diagnosis of Blastomycosis
Histopathology
See budding yeast cells
Serology
Treatment of Blastomycosis
AmphoB or an azole for more mild disease
What fungus?
Found in lower Sonoran life zone is semi arid regions of southwest US
Probably associated with burrows of desert animals
Grows rapidly following rain; drought and windy conditions spread organism large distances
Coccidioides immitis

Coccidioidomycosis
The ecological niche of C. immitis is the Sonoran desert, which includes the deserts of the _________ and northern Mexico (figure 18). It is also found in small foci in Central and South America.
Southwest (California, Arizona, New Mexico and Texas)
Pathogenesis of Coccidioidomycosis:
Inhalation of arthroconidia directly into ______
alveoli
arthroconidio
what part of Coccidioidomycosis?
Pathogenesis of Coccidioidomycosis:
arthroconidia transform into a spherule containing _______
endospores
spherule containing endospores.

Endospores can be released and travel through the body leading to extrapulmonary disease
Describe this Coccidioidomycosis picture
Coccidioidomycosis
AKA ____ fever
Valley
Diagnosis of Coccidioidomycosis
Culture of fluid from any involved site
Will grow on many media in few days
Serology- see notes page
Histopathology
See spherules
Treatment of Coccidioidomycosis
Long term treatment required with Ampho B for severe disease or an azole for mild to moderate disease
Candida _______ is responsible for most infections
albicans
Causes of Candida infection in certain situations
T cell immune suppression
Antibiotic therapy
Insertion of catheter
Neutropenia
Disease associations of infection with Candida
Thrush
Vaginal yeast infections
Esophagitis
Candidemia
Pneumonia
Hepatospenic candidiasis
Diagnosis of Candida infection
Culture of blood or biopsied lung tissue
Blood agar or Sabouraud’s agar
Most common species causing human disease: Aspergillus ______ and A. _______
A. fumigatus, A. flavus
Pts At risk for aspergillus: - neutropenic, transplant patients, patients on long term ________
corticosteroids
Most common manifestation of Aspergillus
sinusitis, pneumonia
Histopathology of Aspergillus infection-
see acutely branching septate hyphae; may see fruiting bodies in lung
Agar for diagnosis of aspergillus
Sabouraud’s agar
Treatment of Candida and Aspergillus
Increase neutrophil count with rG-CSF if patient is neutropenic
Anti-fungals:
Amphotericin B, voriconazole, caspofungin
What fungus?
Once thought to be a protozoan, now classified as fungus
May be part of normal flora
May be acquired by inhalation of air-borne cysts
Most individuals acquire the organism by 3 yrs of age
Pneumocystis jiroveci
Pts at risk for Pneumocystis jiroveci
HIV infected with CD4 cell counts <200/cmm
Occasionally seen in other severely immune suppressed patients
Pathogenesis of P. jiroveci:
Replicates in the ______ layer above the alveolar epithelium
surfactant
Pathogenesis of P. jiroveci:
Replicates in the surfactant layer above the alveolar epithelium
Forms trophozoites and _____
cysts
Diagnosis:
Pneumocystis jiroveci
Microscopic examination of BAL fluid stained with Giemsa, toluidine blue, methenamine silver
See thin walled trophozoites and thick walled cysts containing 4-8 nuclei
Treatment and prevention
Pneumocystis jiroveci
TMP/SMX
A 25-year-old man was admitted to a Colorado hospital with a 12-day history of fever, weight loss, fatigue, arthralgias, and productive cough. He had been treated by a private physician with two antibiotics during the preceding 8 days. On hospital admission, a computed tomography (CT) scan demonstrated bilateral pulmonary diffuse nodular opacities. A subsequent open lung biopsy revealed small budding yeasts. After 10 days of culture, Blastomyces dermatitidis was identified and confirmed by DNA probe (GenProbe, San Diego, California *), both at the local hospital laboratory and at CDC. The patient was treated with intravenous (IV) ___________ for 10 days, followed by a prescribed 6-month course of oral ________.
amphotericin B


itraconazole
One week later, a 35-year-old man sought care for a 15-day history of fever, fatigue, shortness of breath, arthralgias, skin lesions (punctate lesions on arms and trunk and lesions resembling erythema nodosum on legs), cough, chest pain, and weight loss. His symptoms did not improve after 9 days of treatment with two antibiotics, and he was admitted to the same hospital as patient 1. A CT scan revealed diffuse, bilateral pulmonary nodules. The consulting physician for this patient also had seen patient 1; on the basis of work history and clinical course of the disease, the consultant suspected a fungal pneumonia. Specimens obtained by transbronchial biopsy/lavage were negative for fungal elements by microscopic examination and culture. Open lung biopsy specimens revealed small budding yeasts morphologically indistinguishable from those found in patient 1. Biopsy specimens grew B. dermatitidis after 21 days of culture. The patient received IV __________ for 14 days, and at discharge, a 6-month prescribed course of oral __________.
amphotericin B


itraconazole
On March 30, 2001, CDC was notified by Pennsylvania Department of Health (PDH) of an acute respiratory febrile illness in 44 students from two colleges who traveled to Acapulco, Mexico, for spring break vacation during March 3--18. Within 7--14 days of their return from Acapulco, 21 students presented to health-care providers with illness characterized by fever, chills, dry cough, chest pain, and headache. Two students were hospitalized. On the basis of clinical symptoms and chest radiographs that revealed bilateral, nodular patchy infiltrates, acute pulmonary ____________ was the suspected illness.
histoplasmosis
The number of cases of Coccidioidomycosis in Arizona has increased in recent years
1995 reported as 14/100,000 (2X more than in previous yrs
Most of new cases were in elderly patients who developed more serious disease
Why?
More elderly moving to AZ from areas where this fungus is not endemic