Thermally Dimorphic Fungi (Exam 3)

What are the culture criteria that must be met for a dimorphic fungus to be diagnosed?

- Slow-growing

- Growth not inhibited by cycloheximide

- Cobweb or hair-like texture to colonies

- Thin hyphae or parallel/ropelike arrangement

- Convert mold to yeast

- Disease is respiratory and/or disseminating

What is the definition and required conditions for dimorphism?

Yeast at 37 C, mold at 25 C

Histoplasma capsulatum yeast

Histoplasma capsulatum mold

Histoplasma capsulatum is acquired through the inhalation of ______ from soil via wind.

spores

What disease(s) does Histoplasma capsulatum cause?

- Mild to disseminated

- Asymptomatic to flu-like

- Infection of reticuloendothelial system

- Darling's disease

- Spelunker's disease

Where is Histoplasma capsulatum commonly found?

Mississippi, Missouri, Ohio River Valleys

What treatments are used for Histoplasma capsulatum?

- Itraconazole

- Liposomal Amphotericin B

Blastomyces dermatitidis yeast

Blastomyces dermatitidis mold

Blastomyces dermatitidis is acquired through the inhalation of ______.

microconidia

What disease(s) does Blastomyces dermatitidis cause?

- Mild to disseminated

- Rarely infectious (opportunistic)

- Fulminant (dense fungal burden) = fever, adenopathy, anemia

- Chronic respiratory infection

- Gilchrist's disease

Where is Blastomyces dermatitidis commonly found?

- Great Lakes

- East to Kentucky and Carolinas

- North to Canada, Wisconsin

What are the treatments used against Blastomyces dermatitidis?

- Itraconazole

- Liposomal Amphotericin B

Coccidioides immitis tissue phase

Round, refractive spherules filled with endospores

Coccidioides immitis mycelial phase

Coccidioides immitis can be contracted via inhalation of ______.

spores

What disease(s) are caused by Coccidioides immitis?

- Coccidioidomycosis (flu-like, repiratory)

- Disseminated (CNS, skin, musculoskeletal)

- African American, Filipino and Latino descent more at risk

Where is Coccidioides immitis commonly found?

- San Joaquin Valley

- Hot, semi-arid desert

- Southwest states

What treatments are used for Coccidioides immitis infection?

- Fluconazole or itraconazole

- Liposomal Amphotericin B

Paracoccidioides brasiliensis yeast

Paracoccidioides brasiliensis mold

White/cream colored

Flat, membranous, turning beige or brown

Paracoccidioides brasiliensis is acquired via inhalation of ______.

conidia

What disease(s) does Paracoccidioides brasiliensis cause?

- Paracoccidioidomycosis (TB type lesions)

- Mucocutaneous paracoccidioidomycosis (oral mucosa and gums, crusted ulcers)

- Visceral paracoccidioidomycosis (intestines, liver, spleen, adrenals)

Paracoccidioides brasiliensis is most commonly found where?

- South America

- Central America

- Southern Mexico

What treatments are used for Paracoccidioides brasiliensis infection?

- Itraconazole

- Amphotericin B

- Trimethoprim-sulfamethoxazole

Sporothrix schenckii yeast

Rice/cigar shaped

Sporothrix schenckii mold

Bunches of grapes

Sporothrix schenckii is acquired by ______.

skin puncture

What disease(s) does Sporothrix schenckii cause?

- Rose Gardener's disease

- Cutaneous and subcutaneous

- Sporotrichosis (cutaneous, pulmonary)

- Dissemination only in immunocompromised patients

Where is Sporothrix schenckii commonly found?

Worldwide

What treatments can be used against Sporothrix schenckii infection?

- Itraconazole

- Amphotericin B

Penicillium marneffei yeast

Penicillium marneffei mold

Penicillium marneffei is acquired via inhalation of ______.

conidia

Penicillium marneffei is opportunistic, especially in ______ patients.

HIV

Penicillium marneffei is most commonly found where?

- Southeast Asia

- Southern China

What treatments can be used against Penicillium marneffei infection?

- Amphotericin B

- Itraconazole