CDIFF

Question 1

definition of acute infectious diarrhea

Answer 1

• increase freq of defecation lasting <14d
• diarrhea >= loose or liquid stools or more freq than personal normal
• cause by 1 or more microorganism

Question 2

bacterial causes of acute infectious diarrhea

Answer 2

1. campylobacter jejuni
2. salmonella typhio
3. shigella spp.
4. eshcerichia coli
5. vibrio cholera
6. clostridioides difficile

Question 3

protozoal causes of acute infectious diarrhea

Answer 3

1. giardia intestinalis
2. entamoeba histolytica
3. cryptosporidium parvum

Question 4

viral causes of acute infectious diarrhea

Answer 4

1. notovirus
2. rotavirus
3. adenovirus

Question 5

diagnosis for acute infectious diarrhea

Answer 5

1. fecal occult blood, ova and parasite
2. stool cultures
3. polymerase chain reaction PCR

Question 6

who are diagnostic test usually for

Answer 6

patients with:

1. severe illness
2. persistent fever
3. bloody stools
4. immunosuppression
5. unresponsive to tx

Question 7

prevention of acute infectious diarrhea

Answer 7

1. good hand food hygiene

2. vaccinations (eg. cholera, typhoid, rotavirus)

Question 8

non pharmacological tx for acute infectious diarrhea

Answer 8

1. early re-feeding as tolerated

2. easily digestible food (crackers, toast, cereal, banana)

Question 9

pharmacological tx for acute infectious diarrhea

Answer 9

1. self care: oral rehydration therapy, anti-peristaltics, adsorbents, probiotic
2. ABX

Question 10

clinical benefits of antibiotics for acute infectious diarrhea

Answer 10

• reduce duration of symptoms

- reduce mortality and morbidity

Question 11

indications for antibiotics for acute infectious diarrhea

Answer 11

1. severe disease (fever w bloody diarrhea, mucoid stools, severe abdominal pain, cramps, tenderness)
2. sepsis
3. immunocompromise

Question 12

empiric therapy for acute infectious diarrhea

Answer 12

1. ceftriaxone IV 2g q24h
2. ciprofloxacin PO 500mg BD
   IV to PO step down not usually necessary (unless in to out pt)
   duration: 3-5d (may extend in pt w bacteremia, extra intestinal infections, immuno)

Question 13

describe clostridioides difficile

Answer 13

• gram pos
• spore forming anerobic bacillus
• commonly causing nosocomial diarrhea
• increase duration of hospitalisation and increase healthcare cost

Question 14

transmission of Clostridioides difficile

Answer 14

1. fecal-oral route
2. contaminated environmental surfaces
3. hand carriage by healthcare workers

Question 15

C.diff risk factors

Answer 15

1. healthcare exposure:
   - prior hospi
   - duration of hospi
   - nursing homes/ long term care facilities
2. pharmacotherapy:
   - systemic exposure: number of agents and duration of tx
   - high risk: clinda, FQ, 2-5th gen cephlo
   - use of gastric acid suppressive therapy
3. patient-related:
   - multiple/ severe comorbidites
   - immunosuppression
   - advanced age >65yo
   - Hx of DCI

Question 16

clinical presentation of CDI (Mild, mod,sev)

Answer 16

mild:
- loose stool abdominal cramps

moderate:

• fever, malaise, nausea
• abdominal cramps, distension
• leukocytosis
• hypovolemia

severe or fulminant ( 1-3% of CDI pt):

• ileus
• toxic megacolon
• pseudomembranous colitis
• perforation
• death

Question 17

diagnosis of CDI

Answer 17

1. clinical suspicion: unexplained new onset of diarrhea (>=3 unformed stool in 24h; radiologic evidence of ileus or toxic megacolon)
2. confirmatory test: positive stool test result for cdiff or its toxins; histopathologic findings of pseudomembranous colitis
3. culture not routinely done

Question 18

types of diagnostic test for Cdiff

Answer 18

1. nucleic acid amplification test NAAT
2. toxin enzyme immunoassay EIA
3. glutamate dehydrogenase GDH EIA
4. PCR

Question 19

when to not perform diagnosis test for CDI

Answer 19

1. asymptomatic patients
2. repeated tested <7d since most test are v specific
3. test of cure, 60% remain positive despite successful tx

Question 20

infection control for CDI

Answer 20

healthcare setting:
- pract hand hygiene
- contact precaution recommended for 48h after diarrhea resolves
- gloves + gown + wash hand w soap & water
at home:
- wash hands w soap and water after using bathroom
- use separate bathroom
- clean toilets, linens, towels, clothing with bleach

Question 21

when to do empiric CDI tx

Answer 21

substantial delay >48h in diagnostics, or fulminant CDI

Question 22

definition for non severe CDI

Answer 22

WBC <15 x10^9/L AND SCr <133 umol/L (1.5mg/dL)

Question 23

definition for severe CDI

Answer 23

WBC >15 x10^9/L AND SCr >133 umol/L (1.5mg/dL)

Question 24

definition of fulminant CDI

Answer 24

• hypotension or
• ileus or
• megacolon

Question 25

tx for non severe CDI

Answer 25

first line: - vanco 125mg PO QDS - fidaxomicin 200mg PO BD alternative: - metronidazole 400mg PO TDS

Question 26

tx for severe CDI

Answer 26

- vanco 125mg PO QDS | - fidaxomicin 200mg PO BD

Question 27

tx for fulminant CDI

Answer 27

- metronidazole 500mg IV q8h + - vanco 500mg PO QDS +- vanco 500mg PR QDS (if ileus)

Question 28

using fidaxomin for tx for CDI

Answer 28

- narrow spectrum macrocyclic - inhibit transcription and protein synthesis by binding to RNA polymerase - against gram +ve aerobes and anaerobes

Question 29

benefit of fidaxomicin as tx for CDI

Answer 29

1. lower MIC 2. significant post -antibiotic effect (5.5 to 12.5h) 3. less effect on normal bacteriodes spp in gut 4. may reduce recurrence

Question 30

limits of fidaxomin as tx of CDI

Answer 30

1. v expensive ~2k for 10d tx | 2. limited to severe and or recurrent cases non-responsive to maximal standard therapy

Question 31

tx of second episodic CDI

Answer 31

1. vanco 125 PO QDS x 10d (if previously use metro) 2. fidaxomicin 200mg PO BD x 10d 3. vanco PO 125mg QDS taper down

Question 32

tx of third episodic CDI

Answer 32

1. fidaxomicin 200mg PO BD x 10d 2. vanco 125mg PO taper 3. vanco 125mg PO QDS + rifaximin 300mg PO TDS x 20d 4. fecal microbiota transplant

Question 33

clinical improvement of CDI

Answer 33

- usually improve in 5-7d - dont continue CDI tx for concurrent Abx - no evidence of decrease recurrence for tx >10-14d

Question 34

role of probiotics

Answer 34

- maintain/ restore healhy gut flora | - not recommended for routine use to prevent or treat CDI

Question 35

role of anti-motility agents

Answer 35

- symptomatic relief for diarrhea by inhibiting contraction of intestinal smooth muscle - limited in infectious diarrhea: reduces bowel output, affect ability to perform stool testing - eg. loperamide, diphenoxylate, atropine