C Diff

Question 1

C. Difficile

Answer 1

• Gram “+” spore-forming anaerobe bacillus
• Produces toxins that mediates diarrhea and colitis
• Transmitted fecal-oral route

Question 2

Pathogenesis

Answer 2

• Broad-spectrum antibiotic therapy
• Causes disruption in colonic flora
• C.diff colonization and proliferation
• Releases of toxins A, B and binary toxin CDT
• Causes damage to colonic mucosa

Question 3

Main Abx Offenders for C. Diff

Answer 3

• Clindamycin
• Cephalosporin
• Fluoroquinolones

Question 4

C. Diff Presentation

Answer 4

• Fever
• Abdominal pain
• Leukocytosis
• Watery and perfuse diarrhea
• Can progress to life-threatening toxic megacolon (higher risk in older populations)

Question 5

C. Diff Risk Factors

Answer 5

• Antibiotic use
• Elderly patients
• Increased duration of hospitalization
• Chemotherapy
• GI Surgery
• Nasogastric tubes
• Laxative use
• Alteration of gut pH
• Immunosupression

Question 6

C. Diff Diagnosis

Answer 6

• > =3 unformed stools in 24 hours
• Tests: Stool culture, stool enzyme assay, NAAT/PCR
• Do NOT test unless asymptomatic

Question 7

Enhancing Sensitivity/Specificity of Tests

Answer 7

• Uses 2-step EIA
• Toxin A/B
• Glutamate dehydrogenase
• Treat if BOTH tests are positive or perform NAAT/PCR if contradictory

Question 8

C. Diff Management

Answer 8

• D/C offending agents
• Fluid/electrolyte replacement
• Avoid antimotility agents
• Infection control: hand washing, contact precautions, chlorine-containing cleaners or other sporicidal agents

Question 9

Non-Severe C. Diff Criteria/Treatment

Answer 9

Criteria
-WBC =< 15 x 10^3/mm3
AND
-SCr =< 1.5 mg/dL

Treatment
-Vanco x 10 days
OR
-FDX x 10 days

Alternative
Metro x 10 days

Question 10

Severe C. Diff Criteria/Treatment

Answer 10

Criteria
-WBC >= 15 x 10^3/mm3
OR
-SCr >= 1.5 mg/dL

Treatment
-Vanco x 10 days
OR
-FDX x 10 days

Question 11

Fulminant C. Diff Criteria/Treatment

Answer 11

Criteria

• Hypotension or shock
• Ileus (if complete, may require rectal instillation of vanco)
• Toxic megacolon
• Perforation

Treatment
-Vanco + Metro

Surgery consult recommended

Question 12

1st C. Diff Recurrence Treatment

Answer 12

• If Vanco used first, use FDX x 10 days
• If Vanco or FDX used first, use a tapered Vanco dosing for extended period
• If Metro used first, use Vanco for 10 days

Question 13

2nd C. Diff Recurrence Treatment

Answer 13

-Vanco tapered/pulsed regimen
OR
-Vanco x 10 days followed by rifaximin x 20 days
OR
-FDX x 10 days
OR
-Fecal microbiota transplantation

Question 14

FMT

Answer 14

• Fecal microbiota transplantation

- Should use antibiotics over FMT for 1st/2nd recurrence and save for 3rd recurrence

Question 15

Bezlotoxumab

Answer 15

• Human monoclonal antibody that binds to CD TcdB
• Used in combo with another active agent
• Decreases recurrence rates

Question 16

Probiotics + C. Diff

Answer 16

• Not currently recommended
• Lack of standardization
• Risk of bacteremia in immunosuppressed

Question 17

Cholestyramine + C. Diff

Answer 17

• Not recommended

- Binds to vanco