Deep Fungal Flashcards
Examples of Oral Fungal Infections
end in “-mycosis” most of the time
- Aspergillosis
- Histoplasmosis
- Blastomycosis
- Zygomycosis (Mucormycosis)
- Cryptococcosis
- Coccidioidomycosis
- Paracoccidioidomycosis
General Characteristics of Fungal Infections
Most oral fungal infections are opportunistic infections
deep fungal infections in oral cavity are usually manifestations of disseminated infection
T cell (TH-1) MEDIATED immune responses control growth of fungi and TH1 response increases phagocytosis by neutrophils/macrophages to kill fungus.
Presentation of Oral Deep Fungal Infections
Chronic non-healing ulcers
Clinical differential diagnosis: Squamous cell carcinoma
Referral for medical evaluation if oral lesion is diagnosed
Aspergillosis
- reside in soil, water or decaying organic debris
- Spores are released and inhaled
- 2ND MOST COMMON OPPORTUNISTIC FUNGAL INFECTION (candidiasis is #1)
- Nosocomial infection
- seen in Immunocompromised pts, uncontrolled diabetics, maxillary sinus infection, may follow tooth extraction
Common site:
- palate
- Second most common: tongue
*where you will see fungal infection in oral
Cavity
Histoplasmosis
Species: Histoplasma capsulatum
Most common systemic fungal infection in the US
Dimorphic: Yeast at body temperature, mold in soil
Found in humid areas with soil enriched by bird or bat excrement such as areas of Ohio and Mississippi Rivers
Mode of Transmission: inhalation
Acute: self limited pulmonary infection – primary infection is not an opportunistic infection
Chronic: lung infection appears similar to tuberculosis
Disseminated: Rare Older debilitated patients HIV patients with immune deficiency Immunosuppressed patients Most oral lesions Ulcerated lesions resemble squamous cell carcinoma
Diagnosis of oral lesions: biopsy and microscopic examination
Histology of Histoplasmosis
A dot with a white halo around it and
THAT IS THE HISTOPLASMOSIS ORGANISM
Blastomycosis
species: Blastomyces dermatitidis
rarer than Histoplasmosis
Pulmonary Infection: Inhalation of spores
Men>women (outdoor activities?)
Often cutaneous lesions are verrucous plaques (rough nodules, NOT ulcerations!)
Histology: thick cell wall
“B for Big, B for Blastomycosis”
Zygomycosis/Mucormycosis
Spores are inhaled
-Rhino/sino-orbital cerebral form
-Growth is enhanced by iron (Uncontrolled diabetics who are ketoacidotic have higher serum iron levels***)
Other immunosuppressed or immunodeficient patients are at risk
What systemic disease is often associated with Mucormycosis?
UNCONTROLLED DIABETES MELLITUS
Microscopic Findings of Mucormycosis
L shaped, non septate organisms you find in the necrotic area
Treatment for Mucormycosis
Amphotericin B
Cryptococcosis
species: Cryptococcus neoformans
Transmitted by inhalation of organisms contained in pigeon and bat droppings
Cryptococcal meningitis: most common systemic fungal infection in HIV/AIDS patients
Histology: true capsulated yeast
Coccidioidomycosis
San Joaquin Valley Fever/Valley Fever/western US
Paracoccidioidomycosis
South American Blastomycosis
Management of Deep Fungal Infections
- Biopsy needed of granulomas, often need GMS special stain
- Identification of risk factor(s) such as immunosuppression, HIV/AIDS, uncontrolled diabetes
-Treat with Systemic Antifungals
>Ketoconazole
>Itraconazole
>Amphotericin B (polyene agent, IV formulation because poorly absorbed by GI tract)
