CANDIDA (INTERMEDIATE MYCOSES) Flashcards
Describe Candida spp.
Was first isolated as yeast-like fungus in the lesions of thrush
Animal pathogen of Candida
C. albicans
What are the morphology and staining features?
- Small, oval budding yeast-like fungus which develops pseudomycelia
- Produces thick walled chlamydoconidia when grown on corn meal agar
- Arthrospores can be found in lesions
What are the growth characteristics?
- Grows well on both room temperature and on inoculation
- Aerobe and uses carbohydrates in an oxidative and fermentative pattern
- No surface growth in broth
Candida can withstand freezing. True or False?
True
Describe the variability.
2 major cross-reacting serogroups
What are the reservoirs?
- Alimentary tract
- Lower genital tract
Transmission routes
- Endogenous
- Cow to cow spread
- Infection from the environment
Describe the pathogenesis of avian candidiasis (thrush or sour crop).
- Stunting disease with high mortality in poultry
- Lesions in the mouth and stomach
- Diphtheritic membranes (whitish circular areas or elongated patches along the crest of folds in the mucosa) of the gut and respiratory tract
- Abscesses in the viscera
What are the forms of candidiasis?
- Oral –mucous membranes of the mouth (thrush in poultry)
- Venereal – reproductive system
- Cutaneous – axillary region, inguinal areas
- Generalized
What are the common clinical signs in avians?
- Lesions in the mouth, crop, proventriculus and gizzard
- Diphtheritic membranes become confluent and finally slough off leaving superficial ulcers (Turkish towel-like lesions)
Describe cattle candidiasis (associated with calves on intensive antibiotic regimens).
Present with mastitis and abortion
Describe swine candidiasis.
Ulcerative enteritis
Exhibited with a white pseudomembrane on the tongue, esophagus and stomach
Persistent vomiting and rapid wasting in pigs
Describe horse candidiasis.
Infertility, metritis and abortion
What are the virulence factors?
- Capsular polysaccharides
- Peptidoglycan enzymes
- Mannan (Candida cell walls)
- Proteases and glycoprotein (endotoxin-like activity)
- Lipids and chitins
- Mannoproteins
What is the immunologic profile?
Immune mechanism of the disease
PMNs and macrophages as chief defenses
Opsonin-facilitated phagocytosis
Source of samples is from?
Excretion, secretions
What are the preferred culture media and substrates?
Blood agar
SDA
How do you culture and isolate?
- Demonstration of fungi in tissue sections and scrapings
- Pathogenecity test
- Staining of fungus (PAS, Gomori, methenamine silver, Giemsa, Wright’s)
- Test for circulating antibodies
What are the treatment and agents?
- Amphothericin B
- Miconazole
- Ketoconazole
- Nystatin
- Fluconazole
- Flucytosine
What are the control and prevention methods?
Strict hygiene and sanitation
