Fungi

Question 1

Malassezia furfur (Cutaneous)

Answer 1

“Tinea versicolor
degradation of lipids makes acids that damage melanocyts and cause hypopigmented/hyperpigmented patches
In hot, humid weather”

Question 2

Microsporum, Trichophyton, Epidermophyton (Cutaneous)

Answer 2

Epidermophyton with club-shaped macroconidia.
“Trichophyton with red filamentous hyphae.
Spaghetti and meatball appearance on KOH prep
Human disease except microsporum (dog coats)”

Tinea. Extensive nail infections are often Trichophyton.
“Nail infections often treated with Terbinafine (high concentrations in nail)
Ringworm = dermatophyte”

Question 3

Sporothrix schenkii (Subcutaneous)

Answer 3

“Yeast in tissue
Dimorphic
Cigar-shaped budding yeast that lives on vegetation
Typically spores introduced by a rose thorn”

Ascends lymphatics

Question 4

Coccidioides immitis (Systemic)

Answer 4

Spherules (filled with endospores): lungs

“San Joaquin Valley. SW USA; Valley fever
Pneumonia and meningitis: can disseminate to bone and skin”

Question 5

Histoplasma capsulatum (Systemic)

Answer 5

“Tuberculate chlamydospores. Microconidia. (asexual)
Macrophages filled with histoplasma”

“Mississippi and Ohio river valleys
Pneumonia
Flu-like illness. Calcified pulmonary lesions.”

Question 6

Balstomyces dermatitidis (Systemic)

Answer 6

“Broad based buds
Forestry workers, beaver dams”

“Mississippi river and central america
Inflammatory lung disease and can disseminate to skin and bone
Granulomatous nodules
Broad-based budding”

Question 7

Cryptococcus neophormans (Opportunitic)

Answer 7

"Large capsule
Found in soil, pigeon droppings
Culture on Sabouraud's agar
Stains with india ink
Latex agglutination test detects polysaccharide capsular antigen and is more specific 
Always a yeast"

“Chronic Meningitis, esp AIDS
Cryptococcosis
Soap-bubble lesions in brain
“

Question 8

Candida albicans (Opportunistic)

Answer 8

"Germ tubes = attempt at true hyphae;  Pseudohyphae. 
Systemic or superficial infection
Always a yeast
Forms germ tubes
Grows on blood agar"

Oral and esophageal thrush in immunosuppressed, vulvovaginitis, diaper rash, endocarditis in IV drug users, dissemiinated candidiasis, chronic mucocutaneous candidiasis

Question 9

Aspergillus fumigatus (Opportunistic)

Answer 9

“A for Acute angle branching.
Always a mold”

“Pneumonia
Aspergilloma in lung cavities, especially after TB
Invasive aspergillosis, especially in immunocompromised and those with chronic granulomatous disease
Allergic bronchopulmonary aspergillosis (ABPA) with asthma or CF
Some species produce aflatoxins, associated with HCC”

Question 10

Mucor, Rhizopus (Opportunistic)

Answer 10

“Right angle branching. Non-septate. Mold – not dimorphic.
Always a mold”

“Mucosal membranes, sinuses. Black, necrotic sores. Especially poorly controlled type 1 diabetics
Mucormycosis: mostly in ketoacidotic diabetic and leukemic patients; fungi proliferate in blood vessel walls when there is excess ketone and glucose, penetrate cribriform plate, and enter brain
Rhinocerebral, frontal lobe abscesses
Headache, facial pain, black necrotic eschar on face; may have cranial nerve involvement “