C Difficile Flashcards
Where is C Difficile found?
Soil
Hospital
Child care facilities
Nursing facilities
What is the primary mode of transmission?
Fecal oral route in person to person
With regards to C Dif, what is different in kids? (2)
Kids are more likely to have C Dif in their GI tract asymptomatically.
Infants and young children are less likely to develop symptoms, possibly because of immature surface receptors for these microbes and because they are protected by maternal antibodies.
NB same recurrence rates as adults
What is the incubation period?
2-3 days.
What are two groups of medication that predispose to CDI and why? Within what time frame?
Any other risk factors? (6)
Antimicrobials - They suppress the growth of susceptible microbial flora. Within 12 weeks!
Anti-Neoplastic agents - immunosuppression, changes to gut mucosa and antimicrobial effects. Within 12 weeks!
Other: duration of hospital stay, older age, IBD, immunosuppression, GI surgery and manipulation (including feeding tube), PPI (conflicting data)
Why are HIV patients at a particularly high risk of CDI?
Because of impaired humeral response (4x increased risk)
What is the NAPI strain?
It is a newly emergent, resistant (to fluoroquinolones) and highly pathogenic strain
What are some important pathophysiological features of CDI?
Heat resistance of spores
Toxin production: enterotoxin and cytotoxin causing fluid secretion, mucosal damage and interstitial inflammation
Acid resistance - allows passage through stomach and survival among bile acids
How do kids present?
Big spectrum from asymptomatic to pseudomembranous colitis.
Watery diarrhoea is the most frequent clinical presentation in kids
How do you assess the severity of CDI?
Mild: watery diarrhoea without systemic upset and 4 stool per day with no systemic toxicity (may have mild AP and low grade fever)
Severe: systemic toxicity +/- hypotension, shock, peritonitis, ileus and megacolon
What is typically in the stool with a CDI?
WBC
Blood
Mucous
Which kids are more likely to have severe disease? (4)
Neutropenic with haematological malignancies
HSCT
Hirschsprung’s disease
IBD
How do you confirm the diagnosis of CDI?
Stool:
- EIA for glutamate dehydrogenase, present in most strains of C Dif. (less sensitivity)
- EIA for toxin A and B
- Cell cytotoxin assay (labour intense and expensive)
Scope: pseudomembranous colitis
NB: culture not indicated because slow turnaround time and poor specificity. Not sufficient for diagnosis
How do you treat CDI?
Mild: discontinue antibiotics. Seek help if no improvement at 48 hours
Moderate: Metronidazole PO x 10-14 days
Severe: Vancomycin x 10-14 d PO
Severe and complication: Vancomycin PO and metronidazole IV x 10-14 d
NB vancomycin does not work if given IV
How do you treat recurrence?
What is the rate of recurrence?
First recurrence: treat the same as the first episode
Second recurrence: vancomycin in a tapered or pulsed regimen
15-30%
How do you clean a surface if it may have C Dif?
Hands?
With Chloride containing cleaning agent
Hands: soap and water
Should you test for cure?
No. Treatment does not eradicate C Dif or its toxin
Why is metronidazole not recommended for chronic long term use?
Risk of neurotoxicity
What if mom wants to try probiotics to prevent a recurrence?
Good idea
CPS: while there is no evidence to support probiotics, there may be a role in preventing relapses in patients with recurrent CDI
If a kid is
No, the infection is unlikely to be CDI because of maternal antibodies. Do not test.
