Chapter 24

Question 1

GI Tract Defenses: Oral cavity

Answer 1

lysozyme, saliva, tonsils, normal flora, Secretory IgA

Question 2

GI Tract Defenses: Stomach

Answer 2

low pH, mucus

Question 3

GI Tract Defenses: Intestines

Answer 3

bile, GALT, normal flora, peristalsis

Question 4

GI Tract Diseases

Answer 4

-Tooth and gum infections
-Mixed infections of the gums
-Gastric ulcers
-Acute Infectious Diarrhea
-Acute diarrhea with vomiting
-Hepatitis

Question 5

What can cause tooth and gum infections?

Answer 5

Streptococcus mutans

Question 6

Bacterial causes of diarrhea include

Answer 6

-Salmonella
-Shigella
-Shiga-toxin producing E. coli
◦E. coli O157 H7
-Campylobacter (C. jejuni)
-Cholera (Vibrio cholerae)

Question 7

Human carrier (and reservoir) of Salmonella typhi

Answer 7

Typhoid Mary

Question 8

Infect domestic animals

Answer 8

Salmonella enterica serovars

Question 9

Eggs and contaminated meat

Answer 9

Salmonella enterica serovars

Question 10

One of the most prevalent
causes of food-borne
illnesses

Answer 10

Salmonella enterica serovars

Question 11

Transmission dose as few as
10 organisms

Answer 11

Salmonella enterica serovars

Question 12

Attachment is key virulence
factor

Answer 12

Salmonella enterica serovars

Question 13

Gram negative bacillus and it’s classification based on serology and phage susceptibility assays

Answer 13

Salmonella enterica serovars

Question 14

Invades intestinal epithelial cells (Motility, LPS, fimbriae)

Answer 14

Salmonellosis

Question 15

Symptoms: Nausea, cramps, diarrhea
Recovery: a few days but may
shed organism for 6 months

Answer 15

Salmonellosis

Question 16

40,000 cases annually in US, 1 million cases suspected annually

Answer 16

Salmonellosis

Question 17

Exclusively a human parasite that infects the large intestine

Answer 17

Shigella

Question 18

Called “Dysentery”

Answer 18

Shigella

Question 19

Exotoxin (shiga-toxin) affects
intestine, inhibiting protein
synthesis

Answer 19

Shigella

Question 20

Mostly a bovine intestinal commensal that infects the large and small intestine

Answer 20

E.coli 0157H7

Question 21

Exotoxin (shiga-toxin) produced like
Shigella, affects intestine and kidneys

Answer 21

E.coli 0157H7

Question 22

Causes Hemolytic uremic syndrome (HUS)

Answer 22

E.coli 0157H7

Question 23

Small curved Gram negative rod

Answer 23

Campylobacter jejuni

Question 24

Lives in large intestine of birds mostly chickens and mammals

Answer 24

Campylobacter jejuni

Question 25

Fecal contamination of water and foods

Answer 25

Campylobacter jejuni

Question 26

Leading bacterial cause of human gastroenteritis in the world and USA (2.4 million U.S. cases/year)

Answer 26

Campylobacteriosis

Question 27

Caused by undercooked poultry, shellfish, unpasteurized dairy products, contaminated water

Answer 27

Campylobacteriosis

Question 28

Causes watery to bloody diarrhea

Answer 28

Campylobacteriosis

Question 29

1.Adhesion 2.Invasion 3.Treated with antibiotics

Answer 29

Campylobacteriosis

Question 30

Causes Cholera and secretes Cholera toxin (CT) – A-B toxin

Answer 30

Vibrio cholerae

Question 31

Bacteria never enter host cells

Answer 31

Vibrio cholerae

Question 32

Causes heavy loss of fluid “rice-water stool” and untreated cases can be fatal

Answer 32

Vibrio cholerae

Question 33

Enterotoxins made by bacteria in inappropriately stored food can cause

Answer 33

acute diarrhea with vomiting

Question 34

Bacillus cereus often comes from

Answer 34

Rice

Question 35

Clostridium perfringens often comes from

Answer 35

Meats

Question 36

Staphylococcus aureus often comes from

Answer 36

meats, salads

Question 37

Protozoan parasite

Answer 37

Giardia lamblia

Question 38

Cysts survive in environment (Insensitive to chlorine)

Answer 38

Giardia lamblia

Question 39

Contaminated water source of infection

Answer 39

Giardia lamblia

Question 40

Shed by wild animals into water supply as well as by infected humans

Answer 40

Giardiasis

Question 41

1. G. lamblia attaches to human intestinal wall 2. Diarrhea lasting weeks 3. Treated with anti-parasitic drugs

Answer 41

Giardiasis

Question 42

First identified in 1976

Answer 42

Cryptosporidium

Question 43

Contamination via fecal-oral route (Also in contaminated water)

Answer 43

Cryptosporidium

Question 44

1993 outbreak in Milwaukee, WI (Largest waterborne illness outbreak in US history)

Answer 44

Cryptosporidium

Question 45

Responsible for most childhood morbidity and mortality from diarrhea

Answer 45

Rotavirus

Question 46

Fecal – oral route of infection

Answer 46

Rotavirus

Question 47

Babies lacking maternal antibodies are at risk

Answer 47

Rotavirus

Question 48

Unique morphological appearance, vaccine (MLV) now available

Answer 48

Rotavirus

Question 49

Commonly referred to as “Norwalk virus”

Answer 49

Norovirus

Question 50

Highly infectious, fecal- oral route

Answer 50

Norovirus

Question 51

The cause of almost all acute diarrhea outbreaks in adults (90%). Recent “famous” outbreaks on cruise ships.

Answer 51

Norovirus

Question 52

Hepatitis A

Answer 52

Fecal / Oral

Question 53

Hepatitis B

Answer 53

Blood borne & STD

Question 54

Hepatitis C

Answer 54

Blood Borne (And other?)

Question 55

Hepatitis E

Answer 55

Fecal / Oral

Question 56

Hepatitis is a

Answer 56

Viral infection

Question 57

Signs: Infection and inflammation of the liver cells, Jaundice of the skin

Answer 57

Hepatitis

Question 58

Noninfectious conditions can cause

Answer 58

Hepatitis