C. Diff

Question 1

What is the clinical definition of CDAD?

Answer 1

diarrhea > 3 unformed stools per 24h for > 2 days with no other recognized cause
and detection of toxin A or B in the stool or toxin producing C. difficile in the stool
or visualization of pseudomembranes in the colon via colonoscopy

Question 2

What are the symptoms of c. diff?

Answer 2

diarrhea
fever
abdominal pain
leukocytosis

Question 3

List the three step of pathogenesis for C. diff

Answer 3

Step 1 – exposure to antimicrobial agents establishes susceptibility to CDI through disruption of normal colonic microbiota
Step 2 - exposure to toxigenic Clostridioides difficile
Step 3 – virulent strain or high risk antibiotic or inadequate host immune response

Question 4

Traits of C. diff organism

Answer 4

gram positive
sport forming
anaerobic bacillus
causes toxin mediated disease - two toxins - A & B

Question 5

Which antibiotics have the highest risk to cause CDI?

Answer 5

clindamycin
fluoroquinolones
cephalosporins (especially 3rd and 4th)
ampicillin
carbapenems

Question 6

What antibiotics has a low risk of causing C. diff

Answer 6

penicillin
macrolides
tetracycline
TMP/SMX
aminoglycosides

Question 7

List some risk factors for C. diff

Answer 7

older age
greater severity of underlying illness
gastrointestinal surgery
use of rectal electronic thermometers
enteral tube feeding
antacid therapy (PPI > H2 antagonists)
hospitalization - linked to # of days

Question 8

List some management strategies for C. diff

Answer 8

stop the offending antibiotics - if possible
fluid and electrolyte replacement therapy
avoid drugs which inhibit peristalsis (loperamide)

Question 9

What are some factors that help definition moderate/mild vs severe

Answer 9

severe includes
Leukocytes > 15,000 cell/ul
SCr > 1.5 baseline

Question 10

What are some factors that help define uncomplicated vs complicated

Answer 10

hypotension
shock
ileus or megacolon

Question 11

What is first line initial episode mild to moderate c. diff?

Answer 11

vancomycin 125 mg PO QID f10-14d

Question 12

Alternative first line initial episode mild to moderate c. diff

Answer 12

fidaxomicin 200 mg PO BID f10d
metronidazole 500 mg PO TID f10-14d

Question 13

C diff with initial episode - severe uncomplicated (hypoalbuminemia)

Answer 13

vancomycin 125 mg po qid f10-14d

fidaxomicin 200 mg po bid f10d

Question 14

C diff Initial episode - severe complicated

Answer 14

vancomycin 125-500 mg po qid f10-14d
or via NG tube in conjunction with metro 500 mg IV q8h

vancomycin retention enema sometimes added if ileus

Question 15

c diff initial episode severe complicated but alternative

Answer 15

fidaxomicin 200 mg po bid f10d with IV metronidazole if severe allergy to po vancomycin

Question 16

Management with Pediatrics for C. diff

Answer 16

same principles of tx
- stop antibiotics
- supportive care - fluids, antipyretics, nutrition
- specific tx for pathogen if no improvement after d/c antibiotics

Question 17

List the monitoring parameters for C. diff tx

Answer 17

resolution of diarrhea
resolution of fever, abdominal pain, other sx the pt has
check for antimotility agents
WBC, electrolytes
adherence with therapy - especially complex tapering regimen
adverse effects of drug - agent dependent

Question 18

List some ways for prevention of spread

Answer 18

handwashing with soap and water rather than alcohol gel
gloves and gowns
isolation / separate room and equipment
adequate room cleaning

Question 19

How can pharmacists prevent c. diff

Answer 19

practicing good hygienic practices
deprescribing unnecessary PPIs
avoid anti-motility agents if possible
avoid unnecessary antibiotic use overall
don’t treat asymptomatic c. diff
support narrow spectrum prescribing for other infections

Question 20

Pediatrics mild to moderate initial episode (just medication not dose)

Answer 20

metronidazole
vancomycin

Question 21

Pediatrics severe uncomplicated initial episode (just medication not dose)

Answer 21

vancomycin

Question 22

Pediatrics severe complicated initial episode (just medication not dose)

Answer 22

vancomycin

Question 23

Pediatrics first recurrence mild to moderate (just medication not dose)

Answer 23

metronidazole
vancomycin

Question 24

Pediatrics first recurrence severe uncomplicated (just medication not dose)

Answer 24

vancomycin

Question 25

Pediatrics second or subsequent recurrences (just medication not dose)

Answer 25

vancomycin
or fecal microbiota

Question 26

First recurrence C. diff tx

Answer 26

same as initial episode
same dose for both vancomycin or fidaxomicin

Question 27

Second recurrences C. Diff

Answer 27

prolonged vancomycin
fecal microbiota transplantation
monoclonal antibody
surgery