Clostridium Difficile

Exam Cram

• Organism: gram +ve anaerobic bacillus

• Presentation: watery diarrhoea post antibiotics (cephalosporins, clindamycin, ciprofloxacin, co-amoxiclav- 4 C's)

• Management: PO vancomycin, IV/ PO Metronidazole

• Organism killed by soap and water but not alcoholic hand gel

Outline

Background

C.diff is a common cause of hospital acquired infection and is highly infectious within hospitals. 

Assessment

History

• Diarrhoea & oliguiria

• Recent course of antibiotics or proton pump inhibitor

• Previous C.diff infections

Examination

• Abdo tenderness

• Dehydration: reduced skin turgor, mucous membranes

Investigations

• Stool C.diff antigen & culture

• Blood cultures

• FBC, EUC, LFTs +/- CRP & CMP

• Abdo XR or CT Abdo Pelvis

Diagnosis & Severity

Diagnostic criteria: 

• Symptomatic (diarrhoea) + positive C.diff antigen

Severity (defined by NICE)

1. Non Severe: 

• Nil severe features

2. Severe (1/3 features):

   • WCC > 15

   • Cr > 50% rise

   • Temp > 38.5

3. Fulminant

   • Hypotension or septic shock

   • Evidence of ileus, toxic megacolon or bowel perforation

   • Rapid clinical deterioation

Acute Management 

• Stop offending antibiotic or proton pump inhibitor (seek specialist advice if this isn't straightforward)

• IVF

• Avoid loperamide (risk of toxic megacolon)

• Isolation on ward with hand hygiene soap & water

As per severity

1. Non severe: 

   1. PO Vancomycin

   2. PO Fidoxamicin

2. Severe / fulminant features

   1. Metronidazole IV or PO

Med Reg Notes

Longer Term Management

C.diff antigen can be positive for up to 6 weeks post infection. Therefore do not routinely test for clearance of C.diff if symptoms have resolved. 

Prognosis: diarrhoea lasts usually at least a week. Should not return to work till 48hrs post last episode of diarrhoea. 

High rate of reoccurrence. 

Probiotics have been hypothesised to reduce the rate of reoccurrence. 

Defining Toxic Megacolon

Colon > 6cm on AXR

References and Resources

1. https://cks.nice.org.uk/topics/diarrhoea-antibiotic-associated/diagnosis/investigations/#severity-of-c-difficile-infection

Written in 2024.