Week 3 - C.Diff Case Study Flashcards

1
Q

Hfow many americans die each year from c.diff infections?

A

500,000

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

How is c.diff transmitted?

A

C. diff- transmitted fecal-oral route and hospital workers and devices (fomite) may be intermediaries

Acquired through the ingestion of endospores

Increase in incidence and severity possibly due to the emergence of more virulent strains like B1/NAP1/027, which produce more toxin as well as binary toxin

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

nosocomial

A

Disease that originates in the hospital..

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

What are some risk factors for CDI?

A

Living with infants (84% are carriers)

Taking an antibiotic

Gastric acid suppression - proton pump inhibitors

Antineoplastic (anti cancer drug)

Hospitilization

Immunocomproamised or elderly individuals

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

What does an antibiotic do that increases the risk for acquiring C.Diff?

A

Antibiotics diminish healthy bacteria allowing C. diff to multiply and begin producing toxins

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

How do proton pump inhibitors increase risk for C.Diff?

A

Acidic environment is inhibited and therfore is less effective in killing foreign organisms when they enter the body

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

Why do C. Diff infections frequently reoccur?

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

What are symptoms of C. Diff infection?

A

Fever

Abdominal pain

Watery diarrhea (key symptom)

-3 or more loose stools for 1-2 days sans blood

Dehydration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Pseudomembranous Colitis

A

Severe complications include perforation of colon, dehydration, death

Sepsis- inflammation leading to decrease in blood volume

Toxic megacolon becomes so
swollen that it creates pressure on lungs making breathing difficult

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

DDx

A

Diarrhea can be side effect from many antibiotics

So first step to see if it is C.Diff is to STOP antibiotic

Watery diarrhea is often caused by viruses (rotavirus, Norovirus)

Bacteria (E. coli 157:H7, Vibrio cholerae, Campylobacter, Salmonella, Shigella, Yersinia, and Clostridium difficile)
Protozoan (Giardia, Cryptosporidium, and Cyclospora)

Most if these infections are self-limiting and not life-threatening, but knowing cause is critical for choosing the correct antimicrobial

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

C. Diff Diagnosis

A

Positive stool test for toxin

Increased WBC > 15,000 cells/mm3

Direct visualization by sigmoidoscopy of pseudomembranous colitis

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

What is ELISA?

A

Enzyme linked immunosorbent assay

It tests for toxin A and B, some strains are A-neg and B-pos

If target substance is present in immobilized sample then peroxidase enzyme
generates purple color or can use fluorescence to detect
Toxin only stable for 2hrs

Some pts will be false negative* so more tests may need to be done

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

What test is recommended over ELISA?

A

GDH

C. Diff culture - problem is that pts may carry strain but aren’t having infection.. not used any more.

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

What is pseudomembranous colitis composed of?

A

Neutrophils, dead epithelial cells, and inflammatory debris

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

What is a general feature of the class of bacterial Clostridium?

A

They produce more toxins than any other bacteria genus

Not all of the toxins cause disease*

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

What do clostridium endospores do outside of host?

What is basic outline of endosport to active bacteria?

A

Allows stability of the bacteria..

17
Q

What is the pathology of C. Diff?

A

Healthy microbiome in gut suppresses C. Diff growth

When microbiome is killed (antibiotic) C. Diff can proliferate and the toxins are expressed

Both A and B exotoxins bind recepters to the host colon walls and are glucosylated by glucosyltransferases

Toxin A (enterotoxin) activates the inflammatory cascade and disrupts the intercellular tight junctions causing fluid secretion, mucosal injury, edema, and inflammation.

Toxin B (cytotoxin) disrupts the cytoskeleton, leading to mucosal injury and activation of the inflammatory cascade.
 Inflammation results in fever, watery diarrhea, increase in white blood cells
18
Q

Draw out the infectoin of C. Diff in gut

A
19
Q

How to prevent spread of C. Diff?

A

Some of the EPA approved hospital disinfectants do not kill C. diff spores even though they said they did on the labels
Alcohol-based disinfectants are not effective against spore forming bacteria.

20
Q

What are 6 steps of prevention of C. Diff?

A

Decontamination

Sterilization

Disinfectant

Antiseptic

Sanitizer

Aseptic

21
Q

Decontamination

A

occurs prior to sterilization doesn’t remove microbes but removes chemicals, radioactivity to make safe to handle

22
Q

Sterilization

A

destroys all living organisms, viruses, and endospores so they are no longer able to reproduce

23
Q

Disinfectant

A

reduce organisms to a low enough level that disease is unlikely; inanimate objects since often too toxic to use on human tissues

24
Q

Antiseptic

A

microbicide safe to use on human tissue

25
Q

Sanitizer

A

decrease number of microbes to a safe level but doesn’t eliminate

26
Q

Aseptic

A

procedure performed under sterile conditions

27
Q

What factors effecg sterilization?

A

Concentration of microbe or chemical

Time over which the agent is applied

Temperature (higher temp. takes less time)

Type of organism

Material bearing the microorganism (dirt)

May affect normal flora

-absent growth does not necessarily indicate sterility

28
Q

Draw out the diffeent micro organisms in order form resistant to susceptible..

A
29
Q

Methods of sterilization

A
30
Q

A patient being treated with clindamycin for aspiration pneumonia develops diarrhea. The stool contains a toxin that kills cultured epithelial cells. Stool culture grows an anaerobic gram-positive rod. The same organism is cultured from the patients’ bed pan. Which method will sterilize the bed pan?

A. Boiling 45 minutes

B. Benzalkonium chloride

C. Ethylalcohol 1 hr

D. Saturated steam 121°C 15 min.

E. Heating in an oven 150°C 30 min

A

A. Boiling 45 minutes (must boil for >6hr)

B. Benzalkonium chloride 1hr (dissociates cell membrane lipids)

C. Ethylalcohol 1 hr (not effective)

D. Saturated steam 121°C 15 min.(best answer)

E. Heating in an oven 150°C 30 min. (must heat at 160°C/ 2h)

31
Q

What are recommendations for hospital in preventing C. Diff infections..

A

Track and report

Rapid identification and isolation: anyone admitted with diarrhea or antibiotic history is screened

Controls on antibiotics- limit those antibiotic use and track what prescriptions were being used by patients who contract C. diff

Strategies to minimize infections: wash hands and use gowns or gloves

Put individual in private room or in with another C. diff positive patient

Cleaning rooms with C. diff patients with dedicated or disposable toilet brush

Interdisciplinary team at Jewish Hospital-Mercy health
Cut rates 50% in 6 months. CampaignZERO

32
Q

Treatment steps for metronidazole and vancomycin

A
33
Q

What route would be ideal for a antibiotic in a pt with a C. Diff infection

A

Oral.

The infection is in the guts. There for want to target it.

Also would want to have a low absorption

34
Q

Costs of antibiotics used for C. DIff

A
35
Q

What are other things to remember with treating C. Diff?

A

Rehydration and stop offending antibiotics (20% of patients infection with resolve)

Don’t use antidiarrheal meds since they may slow down removal of bacteria and toxins prolonging infection

Don’t treat asymptomatic carriers

If perforations, surgery to remove colon and use of colonoscopy bag

Recurrence of symptoms is one of the challenges (5-47%) of cases (new antibiotic Fidaxomicin be better at preventing recurrence)

36
Q

What is fecal microbiota therapy?

A
37
Q

What other therapies have been tried?

A

Probiotics are inconsistent in preventing recurrence
Lactobacillus, Streptococcus salivarius, Saccharomyces boutardii and may harbor resistance elements and risk of blood stream infection

Intracolonic vancomycin

Intravenous Immunoglobulin against C. diff antitoxin