MRSA hits those with inflammatory bowel disease

CHICAGO, 06 june 2009-- A Canadian study of people with inflammatory bowel disease shows that they are more likely to become infected with the "superbug" MRSA -- ie, methicillin-resistant Staphylococcus aureus -- than are patients with other gastrointestinal illnesses.

Inflammatory bowel disease covers conditions such as Crohn's disease and ulcerative colitis. The connection to MRSA was reported here during the Digestive Disease Week 2009 convention by Dr. Geoffrey C. Nguyen of the University of Toronto.

Nguyen looked at data on 116,842 hospital admissions for inflammatory bowel disease and found that the rate of MRSA infections increased from 1.6 to 3.8 cases per 1000 admissions between 1998 and 2004.

"This reflected an average 20 percent annual rise in odds of MRSA infection," Nguyen pointed out at a news conference. Rates of MRSA infection were 42 percent higher in the patients with inflammatory bowel disease than in hospitalized patients with other intestinal conditions.

Furthermore, after taking account of other factors, "the presence of MRSA was associated with a four-fold higher in-hospital mortality relative to those without MRSA," Nguyen said.

Again, this association was twice as strong for patients with MRSA who also had inflammatory bowel disease rather than some other GI disease.

"Inflammatory bowel disease patients with MRSA also had a significantly longer length of stay than those without inflammatory bowel disease, at 17.4 days versus 6.1 days, respectively," Nguyen said.

"We also want to caution that the study does not necessarily mean that MRSA is a cause of increased mortality among IBD patients," he told Reuters Health. His group plans to investigate deaths among people with inflammatory bowel disease who had MRSA, to determine the actual cause of death.