An emerging epidemic strain of Clostridium difficile appears to be especially virulent, more resistant to antibiotics, or both, according to several new reports. Researchers have learned that this tough new bug can resist fluoroquinolones and is cropping up in geographically dispersed places.
In one study, researchers collected 187 C. difficile isolates from eight facilities in six states between 2000 and 2003 and compared them with 6,000 isolates collected between 1984 and 1990. One strain, which accounted for 51% of the more recent isolates, was positive for binary toxin and was resistant to gatifloxacin and moxifloxacin. Only 14 isolates collected between 1984 and 1990 were the same strain. A second study examining an outbreak of C. difficile-related diarrhea produced similar findings.
In a third study, researchers found that the use of gastric acid suppressive therapy, particularly proton pump inhibitors, increases the risk of community-acquired C. difficile.
Researchers write that if this epidemic strain continues to spread, care providers should either reconsider using fluoroquinolones or develop other means of controlling C. difficile-associated disease.
They also note that alcohol doesn't kill C. difficile spores, so health care workers should use soap and water, not alcohol-based hand sanitizers, during outbreaks.
An epidemic, toxin gene-variant strain of Clostridium difficile, The New England Journal of Medicine, LC McDonald, et al., December 8, 2005; A predominantly clonal multi-institutional outbreak of Clostridium difficile-associated diarrhea with high morbidity and mortality, The New England Journal of Medicine, VG Loo, et al., December 8, 2005; Use of gastric acidsuppressive agents and the risk of community-acquired Clostridium difficile-associated disease, JAMA, S Dial, et al., December 21, 2005.