The balance shifts

May 27, 2008

The risk of contracting a Clostridium difficile infection following operations for which a "prophylactic" antibiotic is given to prevent infection is 21 times greater now than it was just a decade ago, according to researchers from the University of Sherbrooke in Canada. They report their findings in the June 15 issue of Clinical Infectious Diseases, currently available online.

Surgical operations that have been associated with severe infections, such as open heart surgeries and prosthetic implants, are often accompanied by the simultaneous administration of antibiotics, a strategy which has successfully reduced the number of infections. A consequence of this antimicrobial therapy is a modification in normal flora of the human intestine. In this altered environment, a bacterium named Clostridium difficile can thrive. An infection with C. difficile can cause severe diarrhea, occasionally leading to death.

Historically, the benefits of preventing surgical site infections have outweighed the relatively minor risk of C. difficile infections. However, in 2000 a hypervirulent strain of C. difficile emerged, leading to a dramatic increase in the number of infections and in the severity of those infections.

Researchers from the University of Sherbrooke recently completed a study that calculated the risk of contracting a C. difficile infection when the sole antibiotic given was prophylaxis accompanying surgery and compared the current risk with the risk from a period before the emergence of the hypervirulent strain. They found a 21-fold increase in the risk, from 0.07 percent of patients to 1.5 percent. Of the 40 patients who developed a C. difficile infection after peri-operative antibiotic prophylaxis, 5 either died or developed septic shock. Cefoxitin was most likely to be associated with the contraction of a C. difficile infection.

Because the outcomes of C. difficile infections can be severe, the authors suggested that cases be individually evaluated and if the purpose of the antibiotic therapy is only to prevent infrequent or relatively benign infections, then the risks may outweigh benefits. This may be particularly important with elderly patients, who fare worse with C. difficile infections than do younger people.

In addition, the study’s lead author, Louis Valiquette, MD, MSc, suggested that surgical antibiotic prophylaxis should be used for the shortest duration possible to minimize the risk of C. difficile infection. This would also produce collateral benefits of decreasing cost, reducing microbial-related side effects, and slowing the development of bacterial resistance.

Source: Infectious Diseases Society of America

Explore further: Multiple, co-existing groups of gut bacteria keep Clostridium difficile infections at bay

Related Stories

A sweet defense against lethal bacteria

May 31, 2011

(PhysOrg.com) -- There is now a promising vaccine candidate for combating the pathogen which causes one of the most common and dangerous hospital infections. An international team of scientists from the Max Planck Institute ...

Novel strategies target health care-associated infections

March 14, 2011

Can probiotics prevent pneumonia in patients breathing with the help of ventilators? That's just one question researchers at Washington University School of Medicine in St. Louis hope to answer as part of innovative new studies ...

Recommended for you

Machine Translates Thoughts into Speech in Real Time

December 21, 2009

(PhysOrg.com) -- By implanting an electrode into the brain of a person with locked-in syndrome, scientists have demonstrated how to wirelessly transmit neural signals to a speech synthesizer. The "thought-to-speech" process ...

Quantum Theory May Explain Wishful Thinking

April 14, 2009

(PhysOrg.com) -- Humans don’t always make the most rational decisions. As studies have shown, even when logic and reasoning point in one direction, sometimes we chose the opposite route, motivated by personal bias or simply ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.