Path - Small Intestine and Colon - Micro

Question 1

clinical features of ETEC

Answer 1

severe watery diarrhea

Question 2

clinical features of c. diff (pseudomembranous colitis)

Answer 2

watery diarrhea, fever

Question 3

mode of transmission EIEC

Answer 3

cheese, other foods, water

Question 4

which microorganisms can cause reactive arthritis in HLA-B27 patients?

Answer 4

• vibrio cholera

- shigella

Question 5

mode of transmission C. diff

Answer 5

antibiotics allow emergence

Question 6

clinical features of EHEC

Answer 6

bloody diarrhea

Question 7

mode of transmission campylobacter spp

Answer 7

poultry, milk, other foods

Question 8

clinical features enterobius cermicularis (pinworms)

Answer 8

rectal and perineal itching

Question 9

clinical features of enteric (typhoid) fever (salmonella typhi)

Answer 9

bloody diarrhea, fever

Question 10

clinical features of EIEC

Answer 10

bloody diarrhea

Question 11

clinical features of yersinia

Answer 11

abd pain, fever, diarrhea

Question 12

clinical features of shigella

Answer 12

bloody diarrhea

Question 13

mode of transmission shigella

Answer 13

fecal-oral, food, water

Question 14

mode of transmission salmonella

Answer 14

meat, poultry, eggs, milk

Question 15

clinical features of salmonellosis

Answer 15

watery or bloody diarrhea

Question 16

clinical features intestinal cestodes

• diphyllobothrium latum (fish tapeworms)
• taenia solium (pork tapeworms)
• hymenolepis nana (dwarf tapeworms)

Answer 16

abd pain, diarrhea, nausea

majority are asymptomatic though

Question 17

clinical features norovirus

Answer 17

nausea, vomiting, watery diarrhea, abd pain

Question 18

mode of transmission yersinia

Answer 18

pork, milk, water

Question 19

clinical features of EAEC

Answer 19

nonbloody diarrhea, afebrile

Question 20

4 properties of virulence for campylobacter spp

Answer 20

• motility
• adherence
• toxin production
• invasion

Question 21

mode of transmission EPEC

Answer 21

fecal-oral

Question 22

pathogenesis ETEC

Answer 22

produces heat-labile toxin (LT) and heat-stabile toxin (ST) –> induce chloride and water secretion while inhibiting intestinal fluid absorption

Question 23

most common bacterial enteric pathogen in developed countries and an important cause of traveler’s diarrhea

Answer 23

campylobacter jejuni

Question 24

pathogenesis yersinia

Answer 24

invade M cells and use adhesins to bind to B1 integrins –> pathogenicity island encodes iron uptake system (iron enhances virulence and dissemination)

Question 25

mode of transmission vibrio cholera

Answer 25

fecal-oral, water, shellfish

Question 26

clinical features entamoeba histolytica

Answer 26

abd pain, bloody diarrhea, weight loss

Question 27

clinical features giardia lamblia

Answer 27

acute or chronic diarrhea, malabsorption, weight loss

Question 28

pathogenesis of shigella

Answer 28

taken up by M cells in intestine --> proliferate intracellularly --> escape into lamina propria --> phagocytosed by macrophages --> induce apoptosis --> epithelial damage which allows shigella within intestinal lumen to gain access to basolateral membranes

Question 29

pathogenesis EHEC

Answer 29

O157:H7 and non-O157:H7 produce shiga-like toxins

Question 30

pathogenesis EIEC

Answer 30

invade epithelial cells and cause non-specific features of acute self-limiting colitis (NO shiga toxin)

Question 31

mode of transmission whipple disease (Tropheryma whippelii)

Answer 31

unkown

Question 32

pathogenesis whipple dz (tropheryma whippelii)

Answer 32

organism-laden macrophages accumulate within the small intestinal lamina propria and mesenteric lymph nodes --> impaired lymphatic transport

Question 33

mode of transmission enteric (typhoid) fever (salmonella typhi)

Answer 33

fecal-oral, water

Question 34

clinical features strongyloides

Answer 34

eosinophilia

Question 35

pathogenesis EPEC

Answer 35

produce attaching and effacing lesions in which bacteria attach tightly to enterocyte apical membrane and cause local loss (effacement) of microvilli (NO shiga toxin)

Question 36

clinical features of campylobacter spp.

Answer 36

watery or bloody diarrhea

Question 37

pathogenesis rotavirus

Answer 37

selectively infects and destroys mature enterocytes in small intestine

Question 38

pathogenesis tyhpoid fever (salmonella tyhpi)

Answer 38

taken up by M cells in intestine --> engulfed by mononuclear cells in underlying lymphoid tissue --> disseminate in the blood and lymph

Question 39

mode of transmission ETEC

Answer 39

food or fecal-oral

Question 40

clinical features ascaris lumbricoides

Answer 40

physical obstruction of intestine or biliary tree, hepatic abscesses, pneumonitis

Question 41

mode of transmission EAEC

Answer 41

unkown

Question 42

clinical features of EPEC

Answer 42

watery diarrhea

Question 43

clinical features cryptosporidium

Answer 43

watery diarrhea

Question 44

mode of transmission norovirus

Answer 44

large outbreaks: contaminated food or water sporadic cases: person-person transmission

Question 45

mode of transmission EHEC

Answer 45

beef, milk, produce

Question 46

clinical features adenovirus

Answer 46

diarrhea, vomiting, abd pain

Question 47

principal cause of traveler's dairrhea and spread via contaminated food or water

Answer 47

ETEC

Question 48

what microorganism can cause hemolytic uremic syndrome and ischemic colitis

Answer 48

EHEC

Question 49

pathogenesis c. diff (pseudomembranous colitis)

Answer 49

release toxins that cause ribosylation of small GTPases and lead to disruption of epithelial cytoskeleton, tight junction barrier loss, cytokine release, and apoptosis

Question 50

clinical features of whipple disease (Tropheryma whippelii)

Answer 50

malabsorption

Question 51

pathogenesis of salmonella (nontyphoid)

Answer 51

type III secretion system capable of transferring bacterial proteins into M cells and enterocytes --> activate Rho GTPases --> trigger actin rearrangement and bacterial endocytosis --> allows bacterial growth within endosomes

Question 52

clinical features of cholera

Answer 52

severe watery diarrhea | - "rice water stool"

Question 53

pathogenesis EAEC

Answer 53

attach to enterocytes via adherence fimbriae and aided by dispersin which neutralizes the negative surface charge of LPS (NO shiga toxin)

Question 54

pathogenesis of vibrio cholera

Answer 54

stimulation of adenylate cyclase --> increase in intracellular cAMP --> opens CFTR --> releases CL- into lumen --> draws water into lumen --> severe watery diarrhea