Candidal Infections Flashcards
What is the study of fungi called?
Mycology
What type of organisms are fungi?
Eukaryotic microorganisms
Name 3 areas where fungal infections can occur
- Superficial
- Subcutaneous
- Systemic
Where are most fungal infections found?
Superficially
What is the most relevant fungi to dentistry?
Candida albicans
Describe the biological features of Candida albicans
- Large oval shaped organism
- Dimorphic
- Usually endogenous in origin
- Pathogenicity is attributed to certain virulence factors
What does dimorphic mean?
Exists in two forms (yeast and hyphal)
Name 4 virulence factors of Candida albicans?
- Ability to evade host defences
- Adherence
- Biofilm formation
- Production of tissue-damaging hydrolytic enzymes
Name 4 genes associated with Candida virulence
- SAP4-6 (aspartyl proteinase)
- ALS1-7 and ALS-9 (adhesion)
- HYR1 (hyphal regulation)
- ECE1 (extent of cell elongation)
How does Candida albicans stain in a Gram stain?
Stains as a Gram positive, large ovoid organism
What 2 types of patients tend to be affected by Candida albicans?
- Immunocompromised patients
2. Hospitalised with serious underlying diseases
What are the 4 stages of diagnosis of infection by Candida albicans?
- Clinical features
- Gram stain
- Growth of Sabouraud agar
- Presence of Candidal hyphae on smears
Why is Sabouraud agar used in the identification of Candida albicans?
Bacteria do not grow on this type of agar (only fungi grow)
Name 6 non-specific host defences against Candidal infections
- Skin and mucous membranes
- Secretions (saliva)
- Antimicrobial factors in secretions
- Commensal bacteria
- Phagocytosis
- Natural killer cells
What are 3 antimicrobial factors found in secretions which protect the body from Candidal infections?
- Histatins
- Lactoferrin
- Lysozyme
Why can commensal bacteria act as a defensive factor against Candidal infections?
Inhibit Candidal colonization
What are the 4 types of oral Candidiasis?
- Pseudomembranous
- Hyperplastic
- Erythematous
- Angular cheilitis
What 2 ways may a pseudomembranous oral Candidal infection present?
- Fine whitish deposits on an erythematous patch of mucosa
- More high developed small, soft, white, slightly raised plaques resembling milk curds
(both presentations can be removed by wiping)
Name 2 patient complaints of a pseudomembranous oral Candidal infection
- Slight tingling sensation
2. Foul taste
How are hyperplastic oral Candidal infections presented?
White plaques which cannot be removed by scraping
Where is the most common location for hyperplastic oral Candidal infections?
Cheek mucosa
What is most likely a major element in the cause of hyperplastic oral Candidal infection?
A breach of the integrity of the oral mucosa
What 2 locations are the most common for erythematous oral Candidal infection to occur?
- Tongue
2. Palate
How is angular cheilitis characterised?
Cracks radiating from the angle of the mouth, often associated with small white plaques
