PPI-Associated Clostridium difficile Infection

The FDA recently alerted healthcare professionals and patients that use of proton-pump inhibitors may increase the risk for Clostridium difficile–associated diarrhea.

On reviewing published studies and information from the FDA's Adverse Event Reporting System, the FDA warned the public that use of proton-pump inhibitors (PPIs) may increase the risk for Clostridium difficile–associated diarrhea (CDAD). Although the strength of the association varied widely among studies, most studies found risk for C. difficile infection or disease to be 1.4 to 2.75 times higher in patients with PPI exposure than in those without. Many of the patients affected also had other risk factors, such as antibiotic use, older age, or certain comorbid conditions.

PPIs (and possibly histamine-2 antagonists) alter the gastric pH and can allow overgrowth of C. difficile. Several of these agents are now sold over the counter, without need for a prescription.

Patients taking PPIs should be advised to seek medical care promptly if they experience watery diarrhea that does not improve, abdominal pain, and fever. Those found to have C. difficile infection may require replacement of fluid and electrolytes and may need to discontinue or change a prescribed antimicrobial therapy. Uncommon but serious complications include kidney failure, toxic megacolon, bowel perforation, and even death.

Comment: The literature suggests that PPI use increases risk for several problems in addition to C. difficile infection — for example, nosocomial pneumonia, drug–drug interactions (because PPIs decrease absorption of several antimicrobial and antiretroviral agents), and electrolyte imbalances. The effects of dose and duration are not entirely clear, but using the lowest dose for the prescribed indication — and for no longer than necessary — makes sense.

Unfortunately, PPIs are often prescribed without good reason, such as for stress-ulcer prophylaxis in patients who don't qualify for this therapy. Furthermore, once started, these medications are often continued indefinitely. Over-the-counter availability of PPIs compounds the risk for adverse events by decreasing clinician oversight and, potentially, patient awareness of such risk.

— Lynn L. Estes, PharmD

Published in Journal Watch Infectious Diseases February 22, 2012

# posted by roodbont @ 1:35 AM