People who are admitted to the hospital with inflammatory bowel disease are six times more likely to die in the hospital, and nearly twice as likely to need emergency surgery, if they are also infected with diarrhea-causing Clostridium difficile, British researchers have found.
C. difficile has emerged in recent years as a significant cause of hospital morbidity and mortality, with elderly, immunocompromised, and frequently hospitalized people most at risk. People with IBD are already considered to be particularly vulnerable to C. difficile infection, and the use of immunosuppressant drugs may make them more vulnerable still. Some broad-spectrum antibiotics have also been implicated in facilitating C. difficile infection.
"Our findings reinforce the clinical importance of testing for C. difficile among IBD inpatients, and we further recommend [that] screening of all inpatients with diarrhea for C. difficile infection [be] ... part of mandatory surveillance," investigator Min-Hua Jen, Ph.D., of Imperial College London and colleagues wrote in Alimentary Pharmacology and Therapeutics (2011 April 24 [doi:10.1111/j.1365-2036.2011.04661.x]).
Photo credit: CDC/Dr. Gilda Jones
Clostridium difficile has emerged in recent years as a significant cause of hospital morbidity and mortality.
In the United Kingdom, the incidence of C. difficile infections about doubled between 2002 and 2008 among people with IBD. (The United States saw a similar rise between 1998 and 2004.) Because patients with IBD often present with diarrhea regardless of infection status, surveillance with toxin assays is needed to identify C. difficile as the cause, they noted.
The researchers examined records from 6 years’ worth of admissions at U.K. public hospitals, and found that people who were admitted with IBD and were determined to be infected with C. difficile between 2002 and 2008 had a higher risk of dying in the hospital (adjusted odds ratio, 6.32), than did those who were not infected.
The infected also stayed in the hospital a median 26 days (compared with 5 days for IBD patients who were not infected), and they were 1.87 times more likely to undergo emergency gastrointestinal surgery.
For their research, the investigators looked at National Health Service records from 241,478 hospital admissions for IBD from 2002 to 2008. Of these, 2,402 cases had documented C. difficile, established by in-hospital testing; some 91% of these infections were likely acquired in a hospital setting, as the patients had had recent hospitalizations.
The finding, the investigators wrote, "confirms a rising trend in coexistent C. difficile infection among patient admitted to hospital with IBD over the period 2002-2008," and among these coinfected patients, "there is an increased in-hospital mortality and morbidity."
However, the investigators noted, the trend was seen as flattening out in the last 2 years of the study. "This finding may reflect a growing clinical awareness of the higher risk of C. difficile infection in IBD patients and improvements in management once diagnosis is made," they wrote, acknowledging too that the earlier, rising trend could also have corresponded with better screening for C. difficile.
They also pointed out that a previously published study "indicates that IBD patients treated with corticosteroids in combination with an immunomodulator, such as azathioprine, may have an increased risk" of C. difficile infection (Aliment. Pharmacol. Ther. 2009;3:253-64).
The investigators acknowledged as weaknesses of the study the fact that the type of data they used to identify cases made possible no confirmation of C. difficile infection through corresponding medical or laboratory records. Also, the national records "do not contain information on disease severity, how C. difficile diagnosis was reached, or antibiotic and immunomodulator prescribing, all of which are potential confounders."
However, they wrote, despite its limitations, "our study provides important information quantifying the increased risk of morbidity and in-hospital mortality" among IBD patients infected with C. difficile.
The research was supported by the U.K.’s National Institute for Health Research. Dr. Jen disclosed ongoing support from HERON Evidence Development. Dr. Jen and her coauthors from Imperial College London also receive funding under a research grant from Dr. Foster Intelligence. Neither Dr. Jen nor any of her colleagues declared having any relevant conflicts of interest.