Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbiology > Bacterial GI disease 2, Lect 6 > Flashcards

Bacterial GI disease 2, Lect 6 Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

Shigellosis invade and multiply where in body

A

Invade and multiply in colon epithelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

which bacteria is a Facultative intracellular enteric bacilli causing an inflammatory disease of the large bowel

A

Shigellosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe Shigella

  • gram status
  • does it need oxygen?
  • can it form a spore?
  • motile?
A
  • Gram negative rod
  • Nonspore-former
  • Facultative anaerobe
  • Nonmotile (usually)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

clinical presentation: classic

  1. initial symptoms: fever, cramps, vomiting, watery diarrhea
  2. progresses to dysentery - blood, mucous and Granulocytes (PMN) in stools
A

Shigellosis

  • suspect shigellosis in any patient with fever and diarrheal disease
    • blood and mucus in feces + acute onset
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

shigellosis is unable to ferment which sugar

A

nonlactose fermenting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

treatment of shigellosis

A
  • self limiting disease
  • fluid replacement
  • effective Abx therapy may shorten course
    • many are multiple Abx resistant
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

complications of Shigellosis infection

A
  • Reiter’s syndrome (urethritis, polyarthritis, conjunctivitis): strong association with HLA-B27
  • hemolytic uremic syndrome
  • acute renal failure with poor prognosis
  • **same complication that is linked to E-coli O157:H7
    • Shiga toxin and Shiga like toxin are biochemically identical
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

reservoir for shigellosis

A
  • humans are sole reservoir
    • person to person transmission
    • highly infectious
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

highest incidence of shigellosis is in which patient population

A

children 1-4 yo

  • all ages susceptible
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the four species of Shigellosis? Which is most severe

A
  • ### Group A - S. dysenteriae : most severe
  • ### Group B - S. flexneri
  • ### Group C - S. boydii
  • ### Group D - S. sonnei: least severe
  • **bold: most prevalent in U.S.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

prevention of Shigellosis

A

handwashing is the single most important control measure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Reservoir of salmonellae

A
  • ### these microbes are the normal gut flora of many birds and animals and infect humans through food contamination
    • High frequency of infection with this species in domestic herd/flock animals
  • reservoirs:
    • ​eggs
    • beef products
    • pigs and pork products
    • dogs, cats, pet reptiles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

clinical presentation

  • sudden onset of disease
    • fever, chills, cramps, diarrhea, vomiting
    • 2-3 duration in normal host, more severe in infants and eldery
A

Salmonellosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe salmonellae

  • gram status?
  • can it form a spore?
  • does it need O2?
  • motile?
A
  • gram negative
  • nonspore former
  • facultative anaerobe
  • motile
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

which sugar is salmonellae unable to ferment

A

nonlactose fermenting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

how is salmonellae diagnosed

A
  • Microscopic: fecal leukocytes present
    • more macrophages than PMNs
  • culture: sample food and water and fecal matter
  • unable to ferment lactose
  • Fluorescent antibody (FA) tests
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

treatment of Salmonellae

A
  • ## Supportive therapy for patients of otherwise normal good health
    • ## Maintain fluid and electrolytes
  • ### Antibiotics not required if disease is not systemic
    • ### AIDS patients require special care
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Salmonellosis transmission

A
  • contaminated food and water
  • High dose microbe
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Salmonellosis is most prevenalent at what times of year

A
  • Infection has a strong seasonal trend – sharp increases are evident in summer and fall
20
Q

highest incidence of salmonellosis is in which patient age group

A
  • infants and children 6 months to 5 yrs.
21
Q

Clostridium difficile is associated with which antibiotic induced disease

A

Pseudomembranous colitis

22
Q

Describe Clostridium difficile

  • gram status
  • does it require O2?
  • can it form spores?
A
  • gram positive
  • rod shaped
  • anaerobic
  • subterminal spore former
23
Q

It can be difficult to distinguish pseudomembranous colitis from ulcerative colitis, crohn’s disease, and chronic inflammatory bowel disease. What are three types of disease resulting from C. difficile

A
  1. diarrhea with lower abd cramping: no systemic symptoms
  2. severe colitis without pseudomembrane
    1. diarrhea, fever, nausea
  3. classic PMC
24
Q

presentation of classic pseudomembranous colitis

A
  • #### same symptoms as severe colitis +
  • #### Elevated yellowish plaques 2-10 mm diameter over inflamed regions of mucosa
    • #### The pseudomembrane is a fibrin mesh of necrotic cells, PMNs, monocytes and RBCs.
25
Q

how is pseudomembranous colitis diagnosed

A
  • Detection of toxin in feces
  • Gram stain of stool will reveal Gram positive rods with subterminal spores
  • Culture
  • Many hospitals screen all antibiotic-associated diarrhea patients for toxin
26
Q

PMC treatment

A
  • fluid and electrolyte replacement
  • discontinue original Abx therapy
  • administer new Abx
27
Q

what is a predisposing factor to becoming infected with PMC

A
  • disruption of normal gut flora
    • subsequent colonization by C. diff and release of toxins
    • 10% carry this bacterium as normal flora without problem
28
Q

reservoir of PMC

A
  • asymptomatic patients
  • noncomial outbreaks in hospitals and nursing homes
29
Q

describe Clostridium perfringens type A

  • gram status
  • motile?
  • require O2?
  • can it form spores?
A
  • gram positive rod
  • nonmotile
  • aerotolerant anaerobe
  • spore former
30
Q

clinical presentation

  • Short incubation period
  • Moderate severe diarrhea, abdominal cramping
  • Complete recovery in a day
A

Clostridium perfringens

31
Q

how do people become infected with Clostridium perfringens

A
  • This organism is a common member of gut flora of humans and animals
  • Consumption of grossly contaminated meat, poultry
  • Cooking is not adequate to destroy spores
  • If food is allowed to stand, spores will germinate
32
Q

is Clostridium perfringens a high or low dose organism

A

high dose organism = one must receive a large number of cells to get disease

33
Q

how is Clostridium perfringens diagnosed

A
  • must isolate large numbers of microbe in food and feces
34
Q

describe Baceillus cereus

  • gram status
  • require O2?
  • does it form spores?
  • motile?
A
  • gram positive
  • rod shaped
  • aerobic
  • spore former
  • motile
35
Q

Two forms of Baceillus cereus

A
  1. Emetic form
  2. Diarrheal form
36
Q

Clinical presentation

  • upper GI symptoms 1-5 hours after ingestion of contaminated food
  • vomiting, cramps, diarrhea
A
  • Emetic form of B. cereus
    • preformed toxin
37
Q

clinical presentation

  • abdominal pain, profuse watery diarrhea 1-17 hours after ingestion of contaminated food
A
  • Diarrheal form of B. cereus
  • ingestion of large numbers of vegetative cells that produce toxin
38
Q

How is B. cereus diagnosed

A
  • Afebrile disease
  • high index of suspicion if upper GI illness is evident 1-5 hours after eating or lower GI illness 5-17 hours after eating
  • Isolate more than 105 B. cereus per gram of food or feces
39
Q

where is B. cereus commonly found

A
  • spores are commonly found on grains and vegetables
    • especially rice
  • prevention: Prompt refrigeration of all grain foods after cooking
40
Q

which bacteria is caused by consumption of heat stable preformed toxin in foods

  • Under the proper set of conditions, it is possible to have disease without colonization or infection of the host with this agent
A

Staphylococcal Food Borne Disease

41
Q

clinical presentation

  • Short incubation period of 1-6 hours after food consumption
    • Nausea, vomiting, diarrhea, cramps, acute salivation
    • Self-limiting – complete recovery in 1-4 days
A

Staphylococcal Food Borne Disease

42
Q

what is the virulence factor in Staphylococcal Food Borne Disease that causes symptoms

A
  • Enterotoxin A
    • water soluble and heat stable (can withstand boiling for 30 min)
    • Emetic response is elicited by this toxin – absorbed in gut, stimulus reaches CNS and sends impulse to the vomiting center
    • Diarrheal effects – enhanced fluid transmucosal movement into lumen coupled with decreased water absorption
43
Q

reservoir of Staphylococcal Food Borne Disease

A
  • human
  • toxin is undetectable in foods
  • Toxin produced quickly in warm conditions (just a few hours)
44
Q

How is staphylococcal disease diagnosed

A
  • ## Afebrile disease, not directly communicable
  • ## High index of suspicion with short time between eating and symptoms eruption
  • ### Custard filled baked goods, canned foods, processed meats, potato salad
  • Enterotoxin tests are available and reliable
45
Q

treatment of staphylococcal disease

A
  • symptomatic relief
  • this is an intoxication, Abx are of no help
  • disease course is fast, toxin is not synthesized to any great extent in GI tract
46
Q

What do staphylococcus, B. Cererus, and C. perfringens have in common

A
  • foodborne toxin disease
    • Abx are NOT useful
    • not transmissible in direct person to person fasion
    • toxemias
    • common factors: inadequate cooking, reheating or refrigeration of foods

Microbiology (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions