ID Medical Mycology II - Dimorphic Fungi

Question 1

Dark, moist habitat
Moderate temperature
Do not attack mammals (CMI)

Answer 1

Fungi

Question 2

• Restricted habitat
• Convert to yeast to survive at higher temperatures (thermal dimorphism)
• May infect normal and IC hosts
• Most commonly a granulomatous response

Answer 2

Dimorphic fungi

Question 3

Dimorphic Fungi- Often more clinical disease in _____

Answer 3

males

Question 4

Mississippi and Ohio River basins

Also Africa/ India

Answer 4

Blastomyces dermatitidis

Question 5

Is blasto usually symptomatic

Answer 5

not usually

can go to lungs (fever/cough)

disseminates to skin/bone

Question 6

Blasto buzz words

Answer 6

Pyogranulomatous response

Broad-based budding yeast

Question 7

We thought it was Coccidioides immitis, we saw it in AZ and NM, but now we call this new thing

Answer 7

Coccidioides posadasii

disease: Pulmonary coccidioidomycosis

Question 8

Coccidioidomycosis usually present with ?

Answer 8

erythema nodosum

Question 9

Coccidioidomycosis disiminates to

Answer 9

bone and skin

Question 10

Coccidioidomycosis makes what form in body

Answer 10

Spherules

can be full of spores

Question 11

Coccidioidomycosis buzzwords

Answer 11

Diagnostic forms
Spherules
Alternating arthroconidia
confirmed by positive DNA probe

Question 12

Highest in Mississippi-Ohio River Valley region

Answer 12

Blastomycosis

B. dermatidis

Question 13

Any detectable antibody for coccidioides is what?

Answer 13

Active disease

Question 14

Histoplasmosis

Disease

Answer 14

–Primary pulmonary infection: mild flu-like; may have erythema nodosum

–Chronic pulmonary infection: chronic calcified nodules (looks like TB on CXR)

–Disseminated: rare, usu immunocompromised: oropharyngeal ulcers (tongue), bone, liver, spleen and adrenals

Question 15

Soil saprophyte found in dry, sandy, and alkaline soils associated with hot summers and mild winters

Answer 15

Coccidioidomycosis

Coccidioides immitis

Question 16

Paracoccidioidomycosis
Paracoccidioides brasileinsis
Disease

Answer 16

–1o pulm disease: cough dyspnea, fever, weight loss or asymp

–2o disease: –> acute pulmonary disease (usually in immunocompromised), but more commonly chronic progressive; loves mucocutaneous surfaces; regional LAD

Question 17

Soil saprophyte found in subtropical humid mountain forests of South America; GI tract of bats

Answer 17

Paracoccidioidomycosis

Paracoccidioides brasileinsis

Question 18

Seen in rural areas, often where coffee is grown

Affects Adults and Males

Answer 18

Paracoccidioides brasiliensis

Question 19

Frequently assoc with birds, esp starlings or bat excreta

Highest in Ohio-Mississippi Valley (lots of starlings)

Answer 19

Histoplasmosis

Histoplasma capsulatum/ Ajellomyces capsulatus

Question 20

Paracoccidioidomycosis

Disease

Answer 20

Edentulous
Cervical Lymphadenopathy
Chronic pulmonary disease

Question 21

What 2 fungi can you treat with Bactrim

Answer 21

PCP

and

Paracoccidioidomycosis

Question 22

hematogenous spread from lungs; most commonly affects skin (50%) > bone (25-50%) >GU system, esp prostate (5-22%)

Answer 22

Systemic Blastomycosis

B. dermatidis

Question 23

may manifest lung nodules, chronic cavitary disease and coccidiosis (granulomas with caseating necrosis); most commonly disseminates to bone > meninges > skin

Answer 23

Systemic Coccidioidomycosis

Question 24

Unusual fungal organism that lacks ergosterol (used to be thought of as protozoan)

Answer 24

Pneumocystosis

Pnemocystis jiroveci/carinii

Question 25

Very small yeast, usually in macrophages | Urine antigen test

Answer 25

Histoplasmosis

Question 26

KOH of ulcers or sputum | Biopsy (“mickey mouse” or “pilot wheel” appearance)

Answer 26

Paracoccidioidos

Question 27

Coccidioidomycosis making the DDx

Answer 27

Mycelial phase - Macro: glabrous but become white - Micro: alternating “barrel-shaped” arthrospores ``` Yeast phase: thick walled spherules with endospores KOH of skin, sputum -PCR -Serology -Complement fixation titer ```

Question 28

Blastomycosis making the DDx

Answer 28

- KOH of skin or sputum (find in 60%) - Culture - Biopsy - Serology - DNA probe - Urine antigen test

Question 29

Hyperendemic in peru Introduced by skin trama Mostly in Men and Kids

Answer 29

Sporothrix schenckiiSporothrix brasiliensis Big outbreak in rio de janeiro from cats at the moment

Question 30

Only Zoonosis dimorphic

Answer 30

Sporothrix schenckiiSporothrix brasiliensis

Question 31

Disseminated sporotrichosis

Answer 31

Joint Bone Lung Meninges

Question 32

Disseminated sporotrichosis | Host Risk Factors

Answer 32

Host Risk Factors ETOH Diabetes Late HIV COPD

Question 33

Southeast Asia Bamboo rat range HIV patients

Answer 33

Talaromyces (Penicillium) marneffei

Question 34

Red diffusible pigment “Skeleton hands” Yeast conversion

Answer 34

Talaromyces (Penicillium) marneffei

Question 35

Treatment of Sporotrichosis

Answer 35

Itraconazole Bad= Liposomal amphotericin