Module 9 part 2

Question 1

main groups of enteric bacteria

Answer 1

enterobacteriaceae, cibrionaceae, bacteriodaceae, and pseudomonadacaea

Question 2

E. coli, klebsiella, shigella, and Salmonella are which group of enteric bacteria?

Answer 2

enterobacteriaceae

Question 3

What enteric bacteria cannot ferment lactose?

Answer 3

Salmonella, shigella, and Pseudomonas aeruginosa

Question 4

Bile salts in this growth medium inhibit gram positive bacteria, and lactose fermenters turn pink-purple

Answer 4

MacConkey agar

Question 5

This medium inhibits gram positive bacteria, makes lactose fermenters turn deep purple or black, and E. coli looks metallic green

Answer 5

EMB agar (eosin methylene blue)

Question 6

3 major surface antigens of enterics

Answer 6

O, K, and H antigens

Question 7

Antigen that is the most external component of the LPS

Answer 7

O antigen

Question 8

Antigenic capsule that covers the O antigen

Answer 8

K antigen (think Kapsule)

Question 9

Antigen that makes up the subunits of bacterial flagella, so only motile bacteria have this antigen

Answer 9

H antigen

Question 10

2 main types of diseases caused by enterics

Answer 10

diarrhea and other infections (UTI, pneumonia, bacteremia, sepsis)

Question 11

3 types of intestinal enteric invasion that cause diarrhea

Answer 11

no cell invasion (release exotoxins), invasion of intestinal epithelial cells, and invasion of lymph nodes and blood stream

Question 12

Enterotoxigenic bacteria

Answer 12

E coli and V cholera

Question 13

Enteroinvasive bacteria

Answer 13

E. coli, Shigella, and salmonella enteritidis

Question 14

Enteric bacteria that invade lymph nodes and blood stream

Answer 14

Salmonella typhi, Yersinia enterocolitica, and Campylobacter jejuni

Question 15

Common nosocomial gram neg bacteria

Answer 15

E. coli, Klebsiella pneumoniae, proteus mirabilis

Question 16

How does E. coli acquire virulence?

Answer 16

conjugation via plasmid exchange, lysogenic conversion via temperate bacteriophages, and direct transposon mediated DNA insertion

Question 17

Virulence factors of E. coli

Answer 17

mucosal adherence with pili and invading intestinal epithelial cells, exotoxin production by LT, ST, and shiga-like toxin, endotoxin production

Question 18

What causes traveler’s diarrhea?

Answer 18

E. coli

Question 19

Virulence factor of enterotoxigenic E. coli

Answer 19

pili bind to intestinal epithelia and release heat labile (LT) exotoxin

Question 20

Variation of E. coli that secretes shiga-like toxin or verotoxin

Answer 20

Enterohemorrhagic E. coli (EHEC)

Question 21

How does EHEC cause disease?

Answer 21

inhibits 60S ribosome which inhibits protein synthesis and results in intestinal epithelial cell death

Question 22

What disease is associated with EHEC E. coli 0157:H7 found in infected meat?

Answer 22

hemolytic uremic syndrome (with anemia, thrombocytopenia, and uremia (renal failure))

Question 23

Main virulence factor for enteroinvasive E. coli (EIEC)

Answer 23

plasmid, shared by Shigella too

Question 24

How does E. coli cause UTI’s?

Answer 24

pili help it travel up the urethra to cause cystitis and sometimes pyelonephritis

Question 25

Second most common cause of neonatal meningitis

Answer 25

E. coli meningitis

Question 26

most common cause of gram negative sepsis due to the lipid A component of the LPS

Answer 26

E. coli sepsis

Question 27

Enteric with a capsule but is non-motile (no H antigen)

Answer 27

Klebsiella pneumoniae

Question 28

2nd most common cause of nosocomial sepsis

Answer 28

Klebsiella pneumoniae

Question 29

4 species of Shigella

Answer 29

dysenteriae, flexneri, boydii, and sonnei

Question 30

What enteric has no flagella, does not ferment lactose, or produce H2S?

Answer 30

Shigella

Question 31

transmission method of Shigella

Answer 31

fecal-oral route

Question 32

Clinical symptoms of Shigella infection

Answer 32

diarrhea with flecks of bright red blood and pus, and shallow ulcers in colon found on colonoscopy

Question 33

Structure of Shiga toxin

Answer 33

A subunit and 5 B subunits

Question 34

Which subunit of Shiga toxin is responsible for the toxicity

Answer 34

A subunit

Question 35

Enteric with flagella, produces H2s but does not ferment lactose

Answer 35

Salmonella

Question 36

Virulence factor for Salmonella

Answer 36

Vi antigen around the O antigen that protects it from antibody attack

Question 37

Polysaccharide capsule around the O antigen on Salmonella

Answer 37

Vi antigen

Question 38

3 main serotypes of Salmonella

Answer 38

Salmonella typhi, S. cholerae-suis, and S. enteritidis

Question 39

most common places Salmonella is found

Answer 39

undercooked chicken and eggs

Question 40

Which type of Salmonella is not zoonotic and only carried by humans?

Answer 40

Salmonella typhi

Question 41

Disease also called enteric fever

Answer 41

Typhoid fever

Question 42

Transmission route of Typhoid fever

Answer 42

fecal-oral

Question 43

What does typhoid invade in the body?

Answer 43

intestinal epithelium first, then lymph nodes then multiple organ systems

Question 44

What bacteria is also known as a facultative intracellular parasite?

Answer 44

S. typhi

Question 45

How long does salmonellosis take to develop?

Answer 45

1-3 weeks after exposure

Question 46

Antibiotics to treat typhoid

Answer 46

cipro and ceftriaxone

Question 47

Who are prone to salmonella infections?

Answer 47

no spleen or sickle cell anemic

Question 48

Where do 'carrier state' patients harbor S. typhi?

Answer 48

in their gallbladder

Question 49

What form of salmonella causes sepsis usually?

Answer 49

S. cholerae-suis

Question 50

How does the immune system clear encapsulated bacteria

Answer 50

opsonizing it w antibodies

Question 51

What immune cells in the spleen phagocytize Salmonella bacteria?

Answer 51

macrophages and neutrophils

Question 52

Most common type of salmonella infection caused by everything but typhoid

Answer 52

diarrhea/gastroenteritis

Question 53

Treatment for Salmonella gasstroenteritis

Answer 53

fluid and electrolyte replacement, NOT antibiotics

Question 54

Curved gram neg rod with a single polar flagellum

Answer 54

Vibrio cholerae

Question 55

Transmission route for cholera

Answer 55

fecal-oral route

Question 56

name of cholera toxin

Answer 56

choleragen

Question 57

How does cholera cause death

Answer 57

dehydration

Question 58

Structure of choleragen

Answer 58

2 A subunits and 5 B subunits

Question 59

Mechanism of action of choleragen

Answer 59

B subunits bind to the receptor. A subunit enters the cell membrane and activates a G protein which stimulates adenylate cyclase. this produces increased cAMP and causes active secretion of ions and water

Question 60

bacteria usually associated with immunocompromised nosocomial infections

Answer 60

Pseudomonas

Question 61

obligate aerobic, non-lactose fermenting, gram neg bacteria

Answer 61

Pseudomonas

Question 62

Bacteria that produces a green and blue pigment (pyoverdin and pyocyanin)

Answer 62

Pseudomonas

Question 63

Important Pseudomonas aeruginosa infections

Answer 63

"BE PSEUDO" Burns, Endocarditis, Pneumonia, Sepsis, External malignant otitis media, UTI, Diabetic Osteomyelitis

Question 64

2 pathogenic species of Mycobacterium

Answer 64

mycobacterium tuberculosis and M. leprae

Question 65

thin rods with lipid-laden cell walls, acid fast, and obligate aerobes

Answer 65

Mycobacterium

Question 66

mycolic acid bound to a carbohydrate that forms a glycolipid

Answer 66

mycoside

Question 67

mycoside formed by 2 mycolic acids and trehalose, found in virulent strains of M. tuberculosis

Answer 67

cord factor

Question 68

What virulence factor of M. tuberculosis inhibits neutrophil migration and damages mitochondria

Answer 68

Cord factor

Question 69

Mycosides that resemble cord factor with sulfates attached to the disaccharide, that inhibit phagosome fusion with lysosomes

Answer 69

Sulfatides

Question 70

complicated mycoside that acts as an adjuvant on M tuberculosis that activates the protective cellular immune system

Answer 70

Wax D

Question 71

Pathogenesis of TB

Answer 71

facultative intracellular growth, cell mediated immunity (not very good): macrophages present bacteria to CD4+ T cells, which become Th1 cells and produce IFN gamma and TNF alpha and activate macrophages. Destruction of lung tissue occurs and the bacteria can still stick around

Question 72

Clinical manifestations of TB

Answer 72

symptomatic primary TB, asymptomatic primary TB, secondary or reactivation TB (pulmonary TB), pleural and pericardial infection, lymph node infection, sterile pyuria, POTT's disease, arthritis, meningitis, and miliary TB

Question 73

RBCs and WBCs found in the urine but not bacteria

Answer 73

sterile pyuria

Question 74

calcified TB tubercle in the middle or lower lung zone

Answer 74

Ghon focus

Question 75

Vaccine for TB that may result in a false positive PPD

Answer 75

bacillus calmette-guerin (BCG)

Question 76

What could cause a false negative PPD

Answer 76

anergy from steroid use, malnutrition, AIDS, etc

Question 77

Drugs used to treat TB

Answer 77

isoniazid, rifampin, ethambutol, streptomycin, and pyrazinamide

Question 78

Length of treatment for TB

Answer 78

6 months for normal TB and 18-24 mo for drug resistant TB

Question 79

Bacteria that causes leprosy or Hansen's disease

Answer 79

mycobacterium leprae

Question 80

5 subdivisions of Leprosy

Answer 80

Lepromatous leprosy (LL), tuberculoid leprosy (TL), borderline lepromatous (BL), borderline (BB), and borderline tuberculoid (BT)

Question 81

most severe form of leprosy

Answer 81

Lepromatous leprosy

Question 82

symptoms of LL

Answer 82

skin lesions all over the body, destroyed nasal cartilage and saddlenose deformity, blindness, thickening of peripheral nerves and neuropathy

Question 83

Form of leprosy where patients cannot mount a cell mediated immune response

Answer 83

lepromatous leprosy (LL)

Question 84

form of leprosy where patients CAN mount a cell mediated response

Answer 84

Tuberculoid leprosy

Question 85

Form of leprosy where there are only a few well defined lesions on the skin

Answer 85

TL

Question 86

Treatment for mycobacterium leprae

Answer 86

sulfones (like dapsone), rifampin, and clofazamine

Question 87

Common opportunistic infection in AIDS patients

Answer 87

Mycobacterium avium-complex (MAC) disease, caused by non tuberculous mycobacteria (NTM)