Selecting a Treatment Regimen
Î Discontinue inciting antimicrobials as soon as possible since this may influence the risk of CDI recurrence (A-II).
Î If possible, avoid antiperistaltic agents as they may obscure symptoms and precipitate toxic megacolon (C-III).
Î Metronidazole is the drug of choice for the initial episode of mild-moderate CDI.
> The dose is 500 mg orally tid for 10-14 days (A-I).
Î Vancomycin is the drug of choice for an initial episode of severe CDI.
> The dose is 125 mg orally qid for 10-14 days (B-I).
Î Vancomycin orally (and per rectum if ileus is present) with or without metronidazole IV is the regimen of choice for the treatment of severe, complicated CDI.
> Vancomycin is dosed at 500 mg qid orally and 500 mg in ~100 mL NS q6h retention enema. Metronidazole is given at 500 mg q8h IV (C-III).
Î Consider colectomy in severely ill patients.
> Monitoring serum lactate and peripheral WBC count may be helpful in prompting a decision to operate since serum lactate rising to 5 mmol/L and WBC rising to 50,000 per mL have been associated with greatly increased peri-operative mortality. If surgical management is necessary, carry out a sub-total colectomy with preservation of the rectum (B-II).
Î Treatment of the first recurrence is usually with the same regimen as for the initial episode (A-II) but should be stratified by disease severity (mild to moderate, severe or severe/ complicated) as is recommended for treatment of the initial CDI episode (C-III).
Î Do not use metronidazole beyond first recurrence or for long-term chronic therapy due to potential for cumulative neurotoxicity (B-II).
Î Treatment of the second or later recurrence with vancomycin using a taper and/or pulse regimen is the preferred next strategy (B-III).
Probiotics
Î Currently available probiotics are not recommended to prevent primary CDI since there are limited data to support this approach, and there is a potential risk of blood stream infection (C-III).
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