Infectious Disease 3

Question 1

what type of cellular response does influenza A illicit?

Answer 1

cytopathic/cytoproliferative

Question 2

influenza A

Answer 2

RNA, segmented genome

H and N antigens- H allows fusion to host, N allows virus to uncoat

primary viral pneumonia- necrosis of ciliated epithelium, lymphocytes in the submucos

causes localized necrosis, inflammation in respiratory epithelium, and systemic symptoms

Question 3

HOW IS VIRAL pneumonia differ on x ray compared to bacterial

Answer 3

appears diffusely opaque rather than concentrated in a lobe- inflammation is interstitial

Question 4

what is the primary cell type in interstitial pneumonia

Answer 4

macrophages and lymphocytes

Question 5

what happens to the lining of the alveoli in viral pneumonia

Answer 5

exudated material in the airspace condenses into hyaline membrane

Question 6

are the avian influenza strains better or worse than human strains

Answer 6

worse

Question 7

what type of cellular response does measles illicit?

Answer 7

cytopathic/cytoproliferative

Question 8

why was influenza of 1918 so bad?

Answer 8

1. caused extremely aggressive cytokine profile resulting in severe systemic symptoms
2. aggressive replicator

Question 9

measles pathology

Answer 9

one strain, systemic disease

multiplies in epithelial and mononuclear cells

viral growth controlled by T cells, infections controlled by B cells

suppression of cell-mediated immunity = increased disease

pneumonia- peribronchiolar and interstitial lymphocytoic and mononuclear infiltrate- causes multinuclear giant cells in lung

Question 10

defining features of measles pneumonia

Answer 10

clusters of lymphocytes

multinuclear giant cells

Question 11

what type of cellular response does CMV illicit?

Answer 11

cytopathic/cytoproliferative

Question 12

CMV pathology

Answer 12

opportunistic DNA herpes virus

infection of epithelia/endothelial cells- relatviely minor inflammation

causes owl eye inclusion bodies

organs: lungs, liver, kidney, GI tract, CNS (retina)

Question 13

how do you diagnose CMV?

Answer 13

must measure viral load via qPCR

Question 14

two mechanisms for necrotizing inflammation

Answer 14

1. pathogen comes and “eats” host cells

2. pathogen secretes toxins

Question 15

what type of cellular response does amebic dysentery illicit?

Answer 15

necrotizing- eating

Question 16

amebic dysentery

Answer 16

entamoeba histolytica- motile and invasive

single nucleus w/ lots of cytoplasm

invasive trophozoite kills PMNs and is resistant to complement

causes sterile abcess and flask-shaped ulcers in the colon

Question 17

what type of cellular response does pseudomembranous colitis illicit?

Answer 17

toxic necrosis

Question 18

pseudomembranous colitis pathology

Answer 18

caused by clostridium difficle- toxin producing

most common cause of hospital acquired diarrhea

gram pos, spore forming, anaerobic bacillus

colonizes bowel after use of antibiotics disturbs natural microbiome

produces toxins A and B

causes diarrhea and pseudomembrane (fibrin, inflammatory cells, dead cells) formation

Question 19

pseudomembrane

Answer 19

fibrin, inflammatory cells, dead cells

Question 20

what type of cellular response does cryptococcal meningitis illicit?

Answer 20

little inflammation

Question 21

cryptococcal meningitis pathology

Answer 21

cryptococcus neoformans- encapsulated yeast

found in high nitrogen soils

common repiratory infection but can disseminate to meninges

virulence factor- polysaccharide capsule

no toxin, little inflammatory response

Question 22

what are the differential outcomes of cryptococcal meningitis

Answer 22

normal- causes loose granuloma

immunosuppressed- chronic meningitis w/ insidious onset. can cause hydrocephalous

Question 23

cryptococcal meningitis diagnosis

Answer 23

stain and india pink preparation

Ag detection of polysaccharide

culture yeast

Question 24

what disease creates a stainable analogue of melanin

Answer 24

cryptococcal meningitis