Clostridium difficile diarrhoea

Question 1

Pathogen causing C.diff

Answer 1

Gram positive spore-forming anaerobe
Release enteroxins A and B
Spores are very robust - can survive for >40d

Question 2

Epidemiology of C.diff

Answer 2

Commonest cause of antibiotic associated diarrhoea - 25%
100% of antibiotic associated pseudomembranous colitis
Stool carriage in 3% of healthy adults and 15-30% of hospital pts

Question 3

Risk factors for C.diff diarrhoea

Answer 3

Abx - quinolones e.g. ciprofloxacin, clindamycin, cefs, augmentin
Increased age
In hosp with increased length of stay, or with contact with C.diff positive pt
PPIs

Question 4

Clinical presentations

Answer 4

Asymptomatic
Mild diarrhoea
Colitis with pseudomembranes
Pseudomembranous colitis
Fulminant colitis 
May occur up to 2mo after discontinuation of abx

Question 5

What is pseudomembranous colitis

Answer 5

Severe systemic symptoms: fever and dehydration
Abdominal pain, bloody diarrhoea, mucus PR
Pseudomembranes (yellow plaques) on flexi sig

Question 6

Complications of pseudomembranous colitis

Answer 6

Paralytic ileus
Toxic megacolon –> perforation
Multi-organ failure

Question 7

Investigations

Answer 7

Bloods: High CRP, v. high WCC, low albumin, dehydration
FBC
U&Es
CRP
Stool: stool culture
CDT ELISA

Question 8

What is classed as severe c.diff diarrhoea?

Answer 8

>1 of:
WCC >15
CRP >50% above baseline
Temperature >38.5
Clinical/radiological evidence of severe colitis

Question 9

Management of C.diff colitis

Answer 9

General: stop causative abx
Avoid anti-diarrhoeals and opiates
Enteric precautions

Specific:
1st line: Metronidazole 400mg TDS PO 10-14d
2nd line: Vancomycin 125mg QDS PO 10-14d

Severe: 1st line: Vancomycin increase to 250mg QDS if no response (+ may add metronidazole) for 10-14d
max dose 500mg 
Urgent colectomy if: 
Toxic megacolon
Increased LDH 
Deteriorating condition

Question 10

How common is recurrence of C.diff diarrhoea?

Answer 10

15-30%
reinfection or residual spored
Repeat course of metro 10-14d
Vanc if further relapse 25%