4 - Biofilm 3: Candida Flashcards
(32 cards)
How does size impact candidal infections?
- yeast cells approx 25-50x bio volume of bacteria
- less cells occupy more space in infection
- provide scaffold for bacteria and create protective environment
Define a mycofilm.
Fungi and bacteria incorporate in a symbiotic relationship where fungi provide attachment and protection of the bacteria
What are risk factors for developing candidiasis? (11)
- immuno-compromised or suppressed patients
- HIV
- intra-abdominal surgery
- central venous catheter
- parenteral nutrition
- broad-sprectrum antibiotics
- dialysis
- diabetes
- burn patient
- trauma patient
- long term steroid use
What are the classifications of oral candidiasis?
- pseudomembranous
- erythematous
- hyperplastic
- angular cheilitis
- chronic mucocutaneous (systemic infection with oral manifestations)
Give an example of pseudomembranous oral candidiasis.
Thrush
Give an example of erythematous oral candidiasis.
- atrophic (HIV related)
- denture related
Give an example of hyperplastic oral candidiasis.
Candidal leukoplakia (possible pre-malignant)
Describe a pseudomembranous candidal infection.
- commonly known as thrush
- easily wiped off mucosa
- is common in HIV patients or those who use systemic antibiotics
Describe a chronic hyperplastic candidal infection.
- is within tissue
- cannot be wiped off
- requires a biopsy to test for pre-malignancy
- requires systemic anti-fungal to treat
Describe angular cheilitis.
- Candida interacts with gram positive staph bacteria
- requires myconazole to treat
What is Newton’s type 1 stomatitis?
Localised inflammation
What is Newton’s type 2 stomatitis?
Diffuse inflammation
What is Newton’s type 3 stomatitis?
Granular inflammation
Describe denture induced stomatitis.
Candida adhere and colonise acrylic surfaces by co-aggregation and biofilm formation
What are signs and symptoms of denture induced stomatitis?
- inflamed mucosa
- burning sensation
- discomfort
- bad taste
What are the common oral pathogenic yeasts?
- Candida albicans
- candida glabrata
What anti fungal is Candida albicans sensitive to?
- fluconazole
- metroconazole
What anti fungal is Candida glabrata sensitive to?
Nystatin
Describe the morphogenesis of Candida albicans.
- innocuous form when at rest (round)
- stressed form develops a hyphae which can invade tissue and access the blood stream
- adhesion -> hyphal penetration -> vascular dissemination -> endothelial colonisation
What are hydrolytic enzymes?
Enzyme that catalyses the hydrolysis (breakdown) of a substrate through the addition of water
Give examples of hydrolytic enzymes.
- phospholipase
- haemolysin
- proteinase
Describe phospholipase.
- hydrolytic enzyme
- lipid is substrate
- contributes to infection by host cell penetration
Describe haemolysin.
- hydrolytic enzyme
- RBC are substrate
- contributes to infection by facilitating hyphal invasion
Describe proteinase.
- hydrolytic enzyme
- protein is substrate
- contributes to infection by adhesion to epithelial cells
