Microbio Week 8 - Candida (Mini Exam) Flashcards
What is the most common cause of all fungal infections?
Candida
Is Candida a regular member of the human normal microbiota?
Yes!!!
T/F: Candida is not a regular member of the normal microbiota of the oral cavity
FALSE, it is a regular member of the normal microbiota of the oral cavity!!
When can Candida become more invasive and cause a variety of infections?
Immunocompromised
What are the different types of Candida infections?
Superficial mucosal inflammatory rxns
Severe systemic disease
What is the most commonly isolated species of Candida?
Candida albicans
What is the morphology of Candida albicans?
Dimorphic (yeast + mold forms)
Short, non-septate, hyphal outgrowths with no constrictions
Germ tubes
What can you also get the formation of in the dimorphic morphology of Candida albicans?
Germ tubes
When are germ tubes produced in Candida albicans?
Initial stage of hyphal formation
What does the detection of germ tubes help with?
Distinguishing Candida albicans from other yeast
What are the virulence factors of Candida albicans that aid in pathogenesis?
Adhesin proteins
Acid proteases
Phospholipase
What do adhesin proteins do?
Adhesion
What do acid proteases do?
Degradation
What does phospholipase do?
Invasion -> hyphal formation
Where does Candida albicans live in the human body?
Skin
Mucosal membranes
What type of pathogen is Candida albicans?
Opportunistic
What is Candida infection most often due to?
Overgrowth of person’s own normal flora bc of decreased immune protection
How can Candida albicans be transmitted?
Exogenous (catheters, protsthetics)
Person-to-person (birth)
What are some predisposing factors for overgrowth of Candida albicans?
Age (very young + elderly)
HIV, transplant recipients
Malignancy, cytotoxic therapies
Prostheses/dentures
Diabetes/high sugar intake
Sjogrens syndrome, xerostomia
*important to address these in treatment
What diseases does Candida albicans cause?
Oral candidiasis
Skin + nail infections
What is another name for pseudomembranous candidiasis?
Thrush
What does pseudomembranous candidiasis (thrush) look like?
Cream colored, crumbling, curd-like white patches
Does pseudomembranous candidiasis (thrush) rub off easily?
YES
What does erythematous candidiasis look like?
Red inflamed areas of varying size
What does angular chelitis look like?
Painful, cracked sores at corners of mouth
What does chronic hyperplastic leukoplakia look like?
Individual white lesions
Does chronic hyperplastic leukoplakia rub off easily?
NO
(this the difference between chronic hyperplastic leukoplakia and thrush!)
What does median rhomboid glossitis look like?
Smooth or lobulated dark pink/red area on back of tongue
Is median rhomboid glossitis localized or generalized?
Localized
What does median rhomboid glossitis involve?
Central papillary atrophy of tongue
What people is median rhomboid glossitis commonly seen in?
Smokers
Inhalation-steroid users
What is chronic mucocutaneous candidiasis?
Persistent/recurrent Candida infections on skin, nails, oral cavity
What is chronic mucocutaneous candidiasis associated with?
Defects in cell-mediated immunity
Which type of Candida albicans infection is genetic?
Chronic mucocutaneous candidiasis
How do you diagnose Candida albicans?
Direct microscopic exam - wet mount using 10% KOH or silver stain
What does the wet mount using 10% KOH do?
Removes all other cells except yeast and hyphae
What does the silver stain do?
Allows you to visualize hyphae
What are you looking for on the direct microscopic exam when diagnosing Candida albicans?
Round/ovoid yeast cells, pseudohyphae, and hyphae
What are 2 other ways to diagnose Candida albicans?
Culture - using Sab’s agar
Germ tube test
What does Sab’s agar do?
IDs fungal types by color
How do you treat candida albicans?
Nystatin (mouthwash, lozenge, topical forms)
Is there a vaccine for Candida albicans?
NO
