Upgrade to remove ads
Micro: Deep systemic & opportunistic mycoses
Terms in this set (24)
Blastomyces dermatidis is a saprophytic ____ fungus. 2 phases
Blastomyces dermatidis is a saprophytic
fungus; 2 phases are
Part of dimorphic fungus; in soil and culture at 25°C; Spores produced on terminal and lateral conidia
Part of dimorphic fungus; in tissues or culture at ≥37°C; Thick, refractile cell wall
What is the reservoir of Blastomyces dermatidis?
soil (sandy, acid soil near water); Spores survive for long periods, especially when soil enriched with rotting vegetation
How is Blastomyces dermatidis transmitted & to who?
Primarily inhalation of spores
(Transition from mycelial to yeast phase in lung)
Occasional wound contamination
with yeast phase (e.g. dog bite or other accidental contamination)
- very sensitive
What are the risk factors for Blastomyces dermatidis?
- Drought, dust, excavation activity, living near water
- Outdoor activity (can occur in strictly indoor animals)
- Season: summer, fall, winter
What animals are at risk for Blastomyces dermatidis?
- greater risk : ROAMING
- Sporting and larger breeds
- Intact males
- Age 1-5 years
What are the clinical conditions in dogs & cats associated with Blastomyces dermatidis?
- Asymptomatic infections occur
- Localized in
pulmonary system - pneumonia
---Signs depend on tissue(s) affected
---Additional sites commonly affected: Skin, bone, eye, lymph node, testes, brain, subcutaneous tissue, external nares
How can you identify Blastomyces dermatidis?
- Thick-walled yeast with single broad-based buds
- Cytology - visible with Giemsa, Wright's
T/F: Blastomyces dermatidis is zoonotic
How can you diagnose Blastomyces dermatidis?
- Culture - potential zoonotic hazard
- Molecular methods (e.g., PCR)
How should you treat Blastomyces dermatidis?
- Systemic (not topical) anti-fungals
What should you educate the client about Blastomyces dermatidis?
- Treatment required for
months to years
- Relapses occur
Zoonotic transmission possible
- Wear gloves when treating (esp. with exudates)
Histoplasma capsulatum var. capsulatum is a ____ _____ fungus
Histoplasma capsulatum var. capsulatum is a
Describe the mycelial phase of Histoplasma capsulatum var. capsulatum
In soil; Round microconidia, nodular macroconidia
Describe the yeast phase of Histoplasma capsulatum var. capsulatum
In tissues; Thin cell wall, no capsule
What is the reservoir of Histoplasma capsulatum var. capsulatum?
Soil (sandy, acid soil near water); Spores survive for long periods
What ways is Histoplasma capsulatum var. capsulatum transmitted?
, possibly ingested
- Increased exposure with excavation, other sources of increased soil turnover & dust
Converts to yeast phase in lung (37°C)
Reproduce within macrophages
Disseminated via macrophages
What are the risk factors for Histoplasma capsulatum var. capsulatum?
Risk factors in dog same as Blastomyces
- Cat can also be affected
What species does Histoplasmosis occur in?
dogs and cats; rare in ruminants, swine, and poultry
Describe Histoplasmosis in dogs and cats.
caused by H. capsulatum var. capsulatum
- May be restricted to pulmonary system (dogs)
- Disseminated disease - progressive, debilitating
- Multiple tissues affected (FYI: liver, spleen, central nervous system, eyes, bone marrow)
How does Histomycosis contrast with Blastomycosis?
Dogs and cats
- Skin involvement
- In dogs,
involvement is common (rare with blastomycosis)
What are the diagnostics for Histomycosis?
- Histology (Better with special stains)
- Culture - potential
How do you treat Histoplasma?
- Treatment similar to blastomycosis
-Caution when handling open wounds
YOU MIGHT ALSO LIKE...
Haemophilus and Related Bacteria
OTHER SETS BY THIS CREATOR
Toxicology - section 1 part 1
Parasitology - Ancylostoma, Uncinaria, and Bunosto…
Parasitology - Nematodes
Parasitology - Intro to Lab Procedures