Quick Update: 2017 C. difficile Guidelines Summary
Leading photo: Kim JE et al. World J Gastroenterol 2014; 20(35): 12687-12690
Summary of new 2017 C. diff guidelines from IDSA!!!
Testing
ONLY test patients with unexplained, new-onset ≥3 unformed stools in 24 hours (although still not well supported)
IF, and only if, there are no test eligibility criteria in place for patient stool submission, toxin testing should be part of diagnostics (with or without NAAT, before or after NAAT) (this is also not super well supported)
DO NOT repeat testing (regardless of positive or negative) within 7 days and DO NOT test asymptomatic patients except for epi purposes (these are very well supported)
What you can say to physicians
NAAT has suboptimal specificity: multiple repeat testing runs a high risk of false-positive
But sensitivity is exceptional: single tests have very high negative predictive value (typically >99%) for CDI
Diagnostic yield of repeat testing within 7 day period (with either toxin EIA or NAAT) is approximately 2%!!!
ALSO: repeat testing to establish cure has NO value since >60% of patients may remain C. difficile positive even after successful treatment
No reliable biomarkers yet to help diagnose CDI (lactoferrin, calprotectin)
Testing in kids: careful! Infants and toddlers can be colonized
<= 12 mon: should NOT test even if they have (simple) diarrhea
Besides high colonization rate in this age group (up to 40%), some even have detectable toxin production!
Could maybe test if apparent pseudomembranous colitis or toxic megacolon, or if other causes of diarrhea are ruled out
1-2yo: should NOT test routinely, unless other causes have been rule out
>= 2yo: test in cases with prolonged or worsening diarrhea and risk factors (IBD, IC) or recent exposure to healthcare or antibiotics
Infection prevention
CDI patients should have dedicated private rooms/restrooms, and prioritize patients with incontinence to get their own rooms
If need to cohort, group people with same co-infecting organisms (MRSA, VRE, etc)
MUST use contact precautions
Soap and water better than alcohol rub (not super well supported) before and after, especially if poop gets on your hands or after working in areas that are likely contaminated
Even patients should wash hands often to reduce spore burden
Use disposables or make sure things are disinfected
If test result not available the same day, should start CP in the meantime (this is pretty well supported)
May stop at 48 hrs after diarrhea resolves if CDI rates not high, but IF high despite IP measures then should continue until D/C
If during endemic outbreak or repeated infections in same room, should consider daily and/or terminal cleaning with sporicidal agents
Fancy machines don’t have evidence that shows they’re better
Asymptomatic carriers: no evidence to support screening or initiate CP
Stewardship: limit use of fluoroquinolones, clindamycin, and cephalosporins (pretty well supported)
Treatment (adults)
No rec for probiotics for prevention
Stop inciting drugs as soon as possible
If delay in results is expected, just start treating empirically
VAN or fidaxomicin PO (well-supported)
Metronidazole PO now second-line
Fulminant CDI (hypotension or shock, ileus, or megacolon)
VAN PO or PR plus metronidazole IV
Surgery: subtotal colectomy is best
Recurrent CDI
1st recurrence: pulsed and tapered VAN or fidaxomycin
After 1st: pulsed and tapered VAN, VAN then rifaximin, or fidaxomycin
Failed Rx: fecal microbiota transplantation (good evidence!)
Treatment (peds)
VAN or metronidazole, but if severe or recurrent VAN is better
Failed Rx: fecal microbiota too (evidence not as strong as adults)