C. diff Flashcards
pathogenesis of C. diff
1) faecal oral -> colonise intestinal tract
2) disrupt normal flora -> C. diff multiply & produce toxin -> infam & diarrhoea
risk factor for C. diff - Abx use
- dose dependent risk
- greatest risk: clindamycin, 3rd/4th gen cephalosporin
- doxy/tigecycline maybe protective
other risk factors for c diff
1) > 65 yo
2) multiple/severe comorbidities
3) immunosuppression
4) history of CDI
5) GI surgery
6) tube feeding
7) hospitalisation within 1 yr
8) long hospitalisation
9) stay nursing home/long term care facilities
10) Gastric acid suppressive therapy (affect microbiota)
cardinal symptom for C.diff
watery diarrhoea (≥ 3 loose stools in 24 hrs)
symptoms of C.diff vs severity
1) mild
- diarrhoea, abdominal cramp
2) moderate
- fever, diarrhoea, N, malaise
- abdominal cramp & distention
- leukocytosis
- hypovolemia
3) severe
- fever, diarrhoea
- diffused abdominal cramp & distention
- WBC ≥ 15 x10^9 /L
- SCr ≥ 133 micromol/L
4) fulminant (severe, sudden)
- hypotension/shock
- ileus
- megacolon
diagnosis component for C.diff
1) diarrhoea
2) positive stool test for C.diff or toxin OR colonoscopic/histopathologic evidence of psudomembranous colitis
principles of C. diff treatment
1) X asymptomatic treat w positive test
2) discontinue Abx that is not treating C diff
3) narrowest agent possible
treatment for C.diff vs severity
1) non severe
- WBC < 15 x 10^9 AND SCr < 133
- PO vanco -> PO metronidzole
2) severe
- WBC ≥ 15 x 10^ 0 or SCr ≥ 133
- PO vanco
3) fulminant
- hypotension/ileus/megacolon
- IV metronidazole + PO vanco
risk factors for recurrent C.diff
1) other Abx during/initiating treatment
2) defective humoral response against C.diff toxin
3) advanced age
4) severe underlying disease
5) continue use PPi
treatment for recurrent C.diff
PO vanco tapered/pulsed
