6: Fungal Infections Flashcards
Infection from a yeastlike fungal organism
Candidiasis
What is dimorphism and why is it important to candidiasis?
Can exist as hyphae (infectious) or yeast (innocuous)
Most common oral fungal infection in humans?
Candidiasis
Best recognized oral form of candidiasis?
Thrush aka pseudomembranous candidiasis
T/F. Candidiasis is in an abnormal part of the oral cavity.
F. It’s a normal part of the oral environment and is only brought on by opportunistic infections (e.g. antibiotics or steroid inhalers)
What is the clinical appearance of pseudomembranous candidiasis? Where commonly seen?
Cottage-cheese like white plaques that scrape off; dorsal tongue, cheeks or palate
What are two ways to get pseudomembranous oral candidiasis?
Immunosuppresion or broad spectrum antibiotics
What are two symptoms of pseudomembranous oral candidiasis?
Burning sensation and alternating unpleasant bitter/salty taste
What is pseudomembranous candidiasis?
Tangled mass of hyphae, yeasts, desquamated epithelial cells and debris
What candidiasis form is more common than pseudomembranous oral candidiasis?
Erythmatous candidiasis
When does Erythmatous Candidiasis present (3) and with what symptoms (3)?
after broad spectrum antibiotics, antibiotic sore mouth, scalded mouth
2. Median Rhomboid glossitis (loss of filiform papillae), not white (usually red or yellow), scrapes off more easily but is more painful.
What is a risk factor for erythmatous candidiasis?
Xerostomia (e.g. Sogren’s)
How do we treat hyper plastic candidiasis?
Cannot be scraped off, must treat and biopsy
What is the external appearance of chronic multifocal candidiasis?
Angles of the mouth (angular cheilitis)
What are three causes of angular cheilitis?
Loss of vertical dimension, vitamin B deficiency and immunosuppresion
What is the term form exfoliative lesions fate vermillion zone and perioral skin due to superficial candidal infection?
Cheilocandidiasis (Angular cheilitis)
Angular cheilitis can be a mixture of:
20% candidiasis alone, 20% staph aureus alone or 60% a combination of both.
What are two ways to prevent candidiasis?
Take probiotics or eat more yogurt while taking antibiotics
- What is Siversky’s preferred anti fungal tx for candidiasis? Systemic tx?
- For Angular cheilitis?
- Central paillary atrophy?
- Clotrimazole 10mg; Fluconazole
- Mycolog II (Nystatin antifungal 100,000 units/gram and Triamcinolone low dose steroid 0.1%)
- Tongue scraper
What form of candidiasis is caused by 24-hour denture wear, and is confined to the denture-bearing areas of the mouth?
Denture stomatitis
What three things can candidiasis be superimposed on?
Lichen planus, leukoplakia or squamous cell carcinoma
What are three treatments for denture stomatitis?
Tx candidiasis, remake denture, better OHI (remove/soak/brush denture, brush palate)
To be candidiasis, what must be present histologically?
Hyphae or pseudohyphae
What must you be wary of if pt has fungal infections of mouth, skin, nails, nose or other mucosal areas?
Mucocutaneous candidiasis; may be a component of a rare group of immunological disorders
What is the most common systemic fungal infection of the U.S.? What group is especially vulnerable?
Histoplasmosis; those with HIV
What areas typically have more cases of histoplasmosis?
Humid areas; soil enriched by bird or bat excrement
Of the three forms of Histoplasmosis (Acute, Chronic, Disseminated), which manifests oral lesions?
Disseminated; Always secondary to the pulmonary form
Where are most disseminated histoplasmosis forms found in the oral lesions?
Tongue, palate and buccal mucosa
How is histoplasmosis spread? What determines the seriousness?
Airborne spores are inhaled, pass through lungs and germinate; amount of spores inhaled and the immunity of the host
What is the clinical presentation of histoplasmosis?
Solitary, variably painful ulcer of several week’s duration; may have rolled margins, making it look malignant
Histologically, how does histoplasmosis present? What disease is loosely similar to this?
Multinucleated giant cells with granulomas; TB and Sarcodosis
What is the tx for:
- Acute
- Chronic
- None; self limiting
2. IV Amphotericin B if does not resolve (significant kidney damage from Amphotericin B) or 3 months of Itraconazole
What is an opportunistic fungal infection normally from decaying material?
Zygomycosis (aka mucormycosis or phycomycosis)
What group of people is zycomycosis normally found in?
Uncontrolled diabetics w/ ketoacidosis
Why is ketoacidosis helpful to Zygomycosis infection?
Inhibition of binding of iron to transferrin allows > iron serum levels; this allows more bacterial growth
What is the histology of zygomycosis?
90 deg branching thick hyphae w/ extensive necrosis
Tx for zygomycosis?
Surgical debridement and high dose amphotericin B
How may a pt w/ rhinocerberal zygomycosis present (6)?
Nasal obstruction, Bloody noses, Facial pain/swelling/cellulosis, Facial paralysis, Blindness/Seizures (advanced stages)
How is the diagnosis made?
Via histology
Fungal infection with both invasive and non-invasive forms from soil, water, or decay?
Aspergillosis
- The only form of aspergillosis that grows at 37C is:
2. Clinical presentation?
- Pathogenic
- Allergic fungal sinusitis: low grade infection of maxillary sinus forms fungal hyphae which eventually calcify (antroliths) and typically necrosis
T/F. Invasive form of aspergillosis has dramatically increased over the years?
T. Caused by the advent of intensive chemo, AIDS, organ and BMT, uncontrolled DM
What is the mass of fungal hyphae called when they infect the maxillary sinus?
Aspergilloma
What is the differential for a mass found in the maxillary sinus (antrolith)
Sinusitis vs. aspergillosis
Why is there necrosis w/ aspergillosis?
The hyphae occlude blood vessels (in addition to necrosis, can present as granulomas)
What are three ways to tx Aspergillosis in immunocompetent host?
Local debridement, corticosteroid, antifungal
