Fungi: Systemic Mycoses Flashcards
List the 4 systemic mycoses
- Histoplasma
- Blastomyces
- Coccidiodes
- Paracoccidoides
Histoplasma capsulatum is associated with
bat and bird droppings (cave, chicken coops)
Histoplasma capsulatum is endemic to
the midwestern and east central United States near the Ohio and Mississippi River valleys
Histoplasma capsulatum is transmitted via
inhalation of mold spores
Histoplasma and the lungs
macrophages phagocytize the yeast form of Histoplasma capsulatum in the lungs (small oval yeast forms can be seen within macrophages on microscopy)
Histoplasma capsulatum antigen can be detected in body fluids such as ________ during infection
- serum
2. urine
Histoplasma capsulatum yeast cells (intracellular oval bodies smaller than red blood cells) are seen within
macrophages on microscopy
Histoplasma capsulatum is a
dimorphic fungus (grows as mold at 25-30°C and yeast at body temperature (35-37°C))
Histoplasma capsulatum can cause
a variety of calcific deposits in the lungs (i.e. calcified mediastinal/hilar lymph nodes)
the signs and symptoms of chronic histoplasmosis
the signs and symptoms of chronic histoplasmosis (cough, fatigue, weight loss, cavitations in the upper lobes of the lungs) clinically resemble reactivation (secondary) tuberculosis
Histoplasma capsulatum infection is associated with
erythema nodosum (painful skin nodules that most commonly form on the shins)
disseminated histoplasmosis can cause
hepatosplenomegaly
disseminated histoplasmosis is primarily seen in
immunocompromised patients
__________ are effective against histoplasmosis
azoles
____________ is used to treat severe histoplasmosis
amphotericin B
Blastomyces dermatitidis is endemic to the
eastern and central United States near the Ohio and Mississippi River valleys and the Great Lakes region
Blastomyces dermatitidis is
a dimorphic fungus (grows as mold at 25-30°C and yeast at body temperature (35-37°C))
Blastomyces dermatitidis is transmitted via
inhalation of mold spores
the yeast form of Blastomyces dermatitidis
the yeast form of Blastomyces dermatitidis produces a single broad-based bud with a double refractile cell wall approximately the same size as red blood cells
chest X-ray findings of blastomycosis are
chest X-ray findings of blastomycosis are highly variable, but most commonly include patchy opacities or densities
blastomycosis can lead to
pulmonary granuloma formation
disseminated blastomycosis
disseminated blastomycosis (skin, bone, and genitourinary involvement) occurs in immunocompromised patients
in immunocompromised patients, disseminated blastomycosis can affect the
- skin (often manifesting as papules, pustules, ulcers, and verrucous lesions)
- bones (often manifesting as bone pain caused by lytic lesions)
Blastomyces dermatitidis antigen can be detected in body fluids such as
urine
_______ are used to treat mild to moderate blastomycosis
azoles (particularly itraconazole and fluconazole)
_______ is used to treat severe blastomycosis
amphotericin B
Coccidioides immitis a dimorphic fungus that causes
San Joaquin Valley fever
Coccidioides immitis is endemic to the
southwestern United States and northern Mexico
Coccidioides immitis is transmitted via
inhalation of mold spores
mold spores of Coccidioides immitis are found in
mold spores of Coccidioides immitis are found in soil and can become airborne when the ground is disturbed (i.e. earthquakes, dust storms, farming)
Coccidioides immitis is a
dimorphic fungus (grows as mold at 25-30°C and forms yeast-like spherules at body temperature (35-37°C))
in tissue sample, Coccidioides immitis can be seen as
large, yeast-like spherules containing endospores
the spherules of Coccidioides immitis
the spherules of Coccidioides immitis (large yeast-like structures containing endospores) are larger than red blood cells
common manifestations of coccidioidomycosis
community-acquired pneumonia (usually presenting with chest pain, cough, and fever) and arthralgia are common manifestations of coccidioidomycosis
chest radiography in primary coccidioidomycosis
may show unilateral infiltrates, ipsilateral hilar adenopathy, or pulmonary nodule formation, though it is unremarkable in up to half of patients
coccidioidomycosis is associated with
erythema nodosum (painful skin nodules that most commonly form on the shins)
extrapulmonary coccidioidomycosis
(most commonly skin, bone, joint, and CNS involvement) occurs in immunocompromised patients
in immunocompromised patients, disseminated coccidioidomycosis can affect the
- skin
2. bones
in immunocompromised patients, disseminated coccidioidomycosis can cause
- meningitis
_________ are used to treat mild to moderate coccidioidomycosis
azoles (particularly itraconazole and fluconazole)
_______ is used to treat severe coccidioidomycosis
amphotericin B
Paracoccidioides brasiliensis is endemic to
Central and South America
the multipolar budding yeast form of Paracoccidioides brasiliensis resembles a
captain’s wheel
Paracoccidioides brasiliensis is a
dimorphic fungus (grows as mold at 25-30°C and yeast at body temperature (35-37°C))
the multipolar budding yeast form of Paracoccidioides brasiliensis is
typically much larger than a red blood cell
Paracoccidioides brasiliensis is transmitted via
inhalation of mold spores
paracoccidioidomycosis can lead to
pulmonary granuloma formation
disseminated paracoccidioidomycosis can cause
lymphadenopathy (most frequently cervical)
chronic paracoccidioidomycosis often presents with
oral mucocutaneous lesions (painful ulcers with ragged borders and spots of hemorrhage)
_______ are used to treat mild to moderate paracoccidioidomycosis
azoles (particularly itraconazole)
_______ is used to treat severe paracoccidioidomycosis
amphotericin B
