22 March wk4-B

Question 1

What is a dimorphic fungus?

Answer 1

Fungi have several morphologies–yeast and mold. Yeast is a budding form where the cells replicate and divide into new organisms each time. Molds are considered multicellular organisms. The cells grow by way of hyphae. Dimorphic means that the fungus can take either form.

Question 2

Describe Histoplasma capsulatum

Answer 2

This is a dimorphic fungus that lives inside macrophages in as yeast in capsules. Due to preference of mononuclear phagocyte system it causes hepatosplenomegaly. CXR shows diffuse infiltrates, cavitary lesions in upper lobes, calcifications and fibrotic scarring also possible. Will also include hilar adenopathy. Tends to infect the lungs and the bone marrow from which aspirate will show mononuclear cells infiltrated by these cells. This is only a significant infection in immune compromised individuals. Ulcerations of the tongue are characteristic of disseminated disease.

Question 3

Identifying Aspergillus fumigatus

Answer 3

Monomorphic fungus having only a mold form.

Seen in tissues as septate hyphae with acute-angle v-shaped branching

Question 4

Cryptococcus neoformans characteristics

Answer 4

Encapsulated yeast causes meningoencephalitis and pulmonary cryptococcosis in immune compromised. Extracellular because polysaccharide capsule prevents it from be eaten by phagocytes.

Question 5

Blastomyces appearance

Answer 5

Round yeasts with single, broad based buds and doubly refractive walls

Question 6

Coccidioides immitis appearance

Answer 6

Large, thick-walled spherules with endospores.

Question 7

Describe Factitious Disorder

Answer 7

Individuals who make themselves sick in some way in order to take on the “sick role” and be cared for. They often don’t consciously know why they are doing it, but they are aware of their actions overall. More likely in women and health care workers. Appears in the absence of other external rewards such as drugs or other.
Can be done on behalf of others (kids) and is then called factitious disorder imposed on another.

Question 8

Describe conversion disorder

Answer 8

Neurological Sx that are inconsistent with any known mental illness, often acute onset and associated with stress