Brainscape's Knowledge GenomeTM

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


See full index

Clinical 2 - Antibiotics > 2 - C. Dif > Flashcards

2 - C. Dif Flashcards

1
Q

Describe Toxin A

A

-Major pathogenic factor and has been characterized as an enterotoxin that causes intestinal fluid secretion, mucosal injury, and inflammation through actin disaggregation, intracellular calcium release, and damage to neurons.

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

Describe Toxin B

A

-Nonenterotoxic cytotoxin that causes depolymerization of filamentous actin and mediates more potent damage to human colonic mucosa than toxin A.

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

______ = enterotoxin

A

Toxin A

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

______ = cytotoxin

A

Toxin B

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

Which toxin is worse?

A

Toxin B

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

Is C. dif dose dependent?

A

No.

If an AB causes C. diff it needs to be removed, reducing dose of that agent will have no effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

ESBL

A

extended spectrum beta lactamases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the bug of C. dif (characteristics)

A
  • anaerobic
  • GP
  • spore-forming bacilli
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

C. dif colonizes ___% of hospitalized patients (fecal-oral transmission)

A

20-50

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

C. dif causes _____% of antimicrobial-associated diarrhea

A

10-20

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

C. dif causes _____% of antimicrobial-associated colitis

A

50-70

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

C. dif enterotoxin (A) and cytotoxin (B) cause ??

A

infection, inflammation, and colitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

C. dif has __% infection-related mortality

A

5

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

NAP1 strain is hyper-virulent strain of C. dif associated with hyper-production and _________-type toxin

A

C. perfringes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

NAP1 strain associated with _______, first identified in Quebec where incidence increased from 36-156 cases per 100,000 between 1991 and 2003

A

outbreaks

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

Current estimates suggest _____% of CDI associated with NAP1

A

30-50

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

NAP1 is associated with higher rates of ?

A
  • treatment failure
  • 2x recurrence
  • 2x complications
  • 4x attributable mortality compared with non-NAP1
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the main risk factor for CDI?

A

antimicrobial therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

CDI

A

C. difficile infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

When does CDI typically result ?

A

within 4-9 days (up to 8 weeks) after AB therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Which antibiotics are at high risk of causing CDI?

A
  • Cephalosporins
  • Fluoroquinolones
  • Penicillins

CFP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Which antibiotics are at moderate risk of causing CDI?

A
  • Macrolides
  • Sulfonamides

MS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Which antibiotics are at low risk of causing CDI?

A
  • Aminoglycosides
  • Tetracyclines

AT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

List other risk factors for getting CDI (besides being on high-risk antibiotics)

A
  • hospitalization > 72 hours
  • elderly, debilitated, multiple co-morbidities, severe underlying disease, immunocompromised
  • nasogastric tube, gastric acid suppression (antacids, H2 blockers, PPIs)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Why is gastric acid suppression a risk factor for C. dif?

A

PPI’s, antacids, & H2 blockers cause the pH to increase and therefore makes it a better environment for C. dif to grow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are some clinical signs and symptoms of CDI?

A
  • watery diarrhea with >3 unformed stools in 24 hours

- nausea, abdominal pain, high fever, very high leukocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are some complications that can arise from C. dif?

A
  • septic shock

- pseudomembranous or fulminant colitis, ileus, toxic megacolon, perforation (may require colon removal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How is CDI diagnosed?

A
  • positive C. dif toxin in stool of symptomatic patient with diarrhea
  • isolate culture and molecular typing during outbreaks
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Does alcohol kill C. diff?

A

No - it is a spore.

30
Q

List some important strategies for preventing CDI

A
  • environmental cleaning and disinfection (C. dif is very infectious)
  • healthcare worker hygiene and hand-washing (alcohol-based sanitizers not effective against spores)
  • single rooms for patients with known CDI, contact/barrier precautions with gloves and gowns for patients with known or suspected CDI
  • antimicrobial stewardship particularly for Clindamycin, FQs, and cephalosporins (high risk for C. dif)
31
Q

Is the use of probiotics warranted for those with C. dif?

A

Data is inconsistent for the primary prevention of antimicrobial-associated diarrhea or CDI

32
Q

Describe the approach for treating CDI

A

a) Discontinue offending antimicrobial, or replace with lower risk agent if needed
b) Supportive measures with hydration
c) avoid anti-motility agents (ex. loperamide, narcotics)
d) Surgery (loop ileostomy, colectomy) for severe, complicated disease
e) antimicrobial therapy for C. dif infection

33
Q

Why do we want to avoid anti-motility agents (loperamide, narcotics) ?

A

need to get toxin out, don’t want to trap it in

34
Q

What is the 1st line agent for mild-moderate CDI?

Include the duration

A

Metronidazole x 10-14 days

35
Q

Why is Metronidazole the 1st line agent for mild-moderate CDI?

A

-preferred based on lower risk of collateral resistance and cost

36
Q

Metronidazole has ____% response rate but lower 80% for NAP1 strains

A

90

37
Q

____ will require a second treatment

A

1 in 5

38
Q

Describe the response with metronidazole

IMPORTANT

A

typically afebrile within 2 days and diarrhea resolution within 5-7 days

39
Q

Adverse effects of Metronidazole (list 4 besides GI)

A
  • metallic taste (9%)
  • disulifiram-reaction
  • CNS (headache 18%, dizziness, confusion)
  • peripheral neuropathy or neurotoxicity (potentially cumulative with multiple courses of therapy)
40
Q

Is metronidazole expensive?

A

approx $20 for 10 day course

41
Q

Besides metronidazole, what else can be used to treat mild-moderate C. diff? Include duration.

A

Vanco x 10-14 days

42
Q

Why can’t you give Vanco IV for C. dif?

A

Bc you want it in the GI tract where the infection is.

43
Q

Who is vancomycin preferred for in C. dif?

A
  • pregnant or nursing women
  • metro-intolerance
  • metro treatment failure
  • severe infection
44
Q

Is Vanco less effective than metronidazole for C. dif?

A

No - at least as effective as Metro

45
Q

What has fewer side effects:

Metro or Vanco

A

Vanco - since it is oral, vancomycin is not absorbed systemically and SE are not bad like metro

46
Q

What is our concern with giving a patient Vanco?

A

collateral resistance, especially VRE

47
Q

Is Vanco expensive?

A

Yes - capsules are $750

48
Q

When is Vanco suggested?

A

If GI symptoms > 5 days, fever > 3 days, worsening or deteriorating during therapy

**If patient is on metro and still having diarrhea on day 5 of therapy, consider this a failure in treatment

49
Q

Vanco or Metro:

What is better against NAP1?

A

Vanco

50
Q

Severe infection associated with who/what?

A
  • elderly, debilitated, inflammatory bowel disease, immunocompromised
  • serum albumin < 30 g/L and WBC > 15, 000 or abdominal tenderness or SCR 1.5 x baseline
51
Q

What would indicate a very severe infection?

A
  • in critically ill with fulminant infection or septic shock

- ACG suggest ICU, hypotension, T > 38.5, ileum, confusion, WBC > 35,000 or <2000, organ failure)

52
Q

Treatment for a very severe CDI?

A

Vanco 500mg + Metro 500mg

I assume x 10-14 days

53
Q

Why is Vanco 500mg q6h instead of Vanco 125mg q6h ?

A

based on expert opinion only, consider 125mg for PO and 500mg for NG or PR

54
Q

What would constitute recurrence?

A

Symptoms and positive C. difficile toxin within 8 weeks of initial episode.

55
Q

___% chance of recurrence rate with multiple recurrences thereafter

A

25

56
Q

For __________:
Consider probiotics such as Saccharomyces boulardii (500mg q12h), Lactobacilli rhamnosus GG, despite weak evidence for the secondary prevention of recurrent CDI

A

recurrence

57
Q

What is the treatment for the 1st recurrence of CDI?

A

repeat initial therapy (50% response rate)

58
Q

What is the treatment for > 2nd recurrence of CDI?

A

Vanco pulsing or tapering recommended in guidelines despite weak evidence
(ex. 125 mg q6h x 14 days, then q12h x 7d, q24h x 7d and q2-3d x 2-8 weeks

59
Q

What is an alternative drug for recurrent CDI?

A

Fidaxomicin

60
Q

What class if Fidaxomicin in?

A

macrocyclic antimicrobial

61
Q

Fidaxomicin is ______ absorbed therefore well tolerated

A

poorly

62
Q

When is Fidaxomicin used?

A

Used as last option for when multiple recurrence occurs

63
Q

Is Fidaxomicin expensive?

A

Yes - $2200 for 10 days

64
Q

FMT can also be done. What is this?

A

Fecal microbiota transplant - from healthy donor to alter and increase gut diversity

65
Q

Describe how FMT is done

A

performed via nasogastric, nasojejunal, gastrostomy tube, colonoscopy or enema following antimicrobial therapy for C. dif infection

66
Q

FMT has >___% response rate

A

80

67
Q

Cons of FMT?

A
  • lacks standardized products and procedures

- used for desperate patients

68
Q

When are probiotics a risk?

A

Only in immunocompromised patients (introducing bacteria into their gut)

69
Q

What are some other investigational options?

A
  • monoclonal Toxin A and B antibodies

- C. difficile vaccine

70
Q

What AB has HIGHEST risk of causing C. dif ?

A

Clindamycin

Clinical 2 - Antibiotics (14 decks)

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