2 a yeast
DESCRIPTION
TRANSCRIPT
Yeasts
Round to oval, single cells which reproduce by budding
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Yeasts
SELECTED GENERA
Candida
Cryptococcus
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Candidiasis
Candida albicansNon-albicans species
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Ecological Niche
Candida albicans
Endogenous
(mouth, gut, vagina)
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Infections with Candida usually occur when there is some alteration in:
Cellular immunity (Immunocompromised) Normal Flora (Prolonged antibiotics) Physiology (Cardiac surgery, catheter)
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CANDIDIASIS
Skin Vaginitis Urinary tract Mucous membranes Septicemia Endocarditis Pneumonia
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CANDIDIASIS
The fourth most common nosocomial bloodstream infection.
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GEOGRAPHIC OCCURENCE
WORLDWIDE
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Clinical SpecimensCandida
Sputum Scrapings from lesions Blood smears Vaginal discharge Urine Feces Nail clippings
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SEROLOGY There have been several antibody
detection test, but none are significant.
Beta-Glucan measurement is now showing promise
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Therapy
Nystatin Vaginitis Cutaneous
Fluconazole * Itraconazole
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Cryptococcosis
Cryptococcus neoformans
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Cryptococcosis
A sub-acute or chronic infection which may affect the lungs or skin but most commonly manifests as a meningitis
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Typical clinical course Inhalation Mild pneumonia Vision, lethargy, headache Delirium, nuchal rigidity, coma Over a period of months Death if not treated
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Cryptococcus neoformans
Spherical 5-10 microns Narrow- base Surrounded by polysaccharide
capsule
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Cryptococcus neoformans
Virulence factors1. Anti-phagocytic
polysaccharide capsule2. Antioxidant melanin3. Ability to grow at 37 C
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Ecological Niche
Cryptococcus neoformans
• Pigeon droppings
• Chicken droppings
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Isolation of Cryptococcus neoformans from environmental sites in South Carolina
Number Examined
Number Positive
Percent Positive
SITES 79 51 65
SAMPLES 299 137 45
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Cryptococcusportal of entry
Inhalation
inoculation
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Specimen of choice
Cerebrospinal fluid
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Clinical Specimens
Cryptococcosis
•CSF•Sputum•Pus•Biopsy material•urine
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Serological Tests
Cryptococcosis
• Indirect fluorescent antibody• Tube Agglutination• Latex Agglutination (measures antigen)
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Drugs of Choice
Cryptococcosis
•Amphotericin B plus 5-Flucytosine
OR
•Amphotericin B plus Fluconazole
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