C. difficile epidemic continues to worsen

WASHINGTON, Oct. 28, 2008: by Emily Walker, Washington Correspondent MedPage Today - The worst of the national Clostridium difficile epidemic is yet to come, researchers cautioned here. The current C. difficile epidemic strain, NAP1/027, has spread to all 50 states, said Clifford McDonald, M.D., of the CDC's Division of Healthcare Quality and Promotion.

And the epidemic is likely to get worse before it gets better, said others at the Interscience Conference on Antimicrobial Agents and Chemotherapy, held jointly with the Infectious Diseases Society of America (IDSA) meeting.

"I don't think we've peaked yet," said Lance Peterson, M.D., of the Evanston (Ill.) Northwestern Healthcare Research Institute.

C. difficile disease is thought to be the result of antibiotics that disrupt patients' normal gut flora, which makes them susceptible to the C. difficile bacteria on hands and hospital surfaces.

Discharge data showed a four-fold increase in C. difficile rates since 2001, when hospitals first began seeing a surge in patients being infected with the bacteria. Meanwhile, deaths caused by C. difficile have increased five-fold, said Dr. McDonald.

"The total burden of C. difficile infections probably exceeds 500,000 cases annually," said Dr. McDonald. "And from that, we're looking at at least 15,000 deaths caused by or contributed by C. difficile."

The IDSA, with the Society of Healthcare Epidemiology of America, recently published a practicum to prevent the spread of C. difficile, recommending, among other things, restraint when prescribing antibiotics, bleach to clean surfaces during outbreaks, and better hand-washing practices.

The NAP1/027 strain of the bacteria caused outbreaks in Canada during 2003 and 2004, leading to 700 deaths in Quebec province in one year. According to Jacque Pepin, M.D., of the University of Sherbrooke, the rates have now leveled off at about 400 deaths per year, but that's still four times the mortality rate from before the bacterial epidemic.

Current treatment hinges largely on two antibiotics -- vancomycin and metronidazole -- but the effectiveness of those drugs is waning, researchers said.

"[There has been] no improvement in 30 years, and we desperately need new therapies," said David Classen, M.D., of the University of Utah in Salt Lake City.

Slowing the C. difficile epidemic will take something more than current broad-spectrum antibiotic treatment, Dr. Pepin said.

That something may be a procedure called a "fecal transplant."

That is just what it sounds like: taking a fecal sample from a healthy relative of an infected person, filtering the sample, and infusing (usually via enema) the filtrate into the C. difficile patient.

In theory, whatever defenses were depleted from the infected person's intestines by antibiotic treatment will be restored through an infusion of healthy feces, said Dale Gerding, M.D., of Hines VA Hospital in Chicago.

The procedure is fairly rare, and is practiced just in Norway and several places in Canada. But it has led to success rates of about 90%, Dr. Gerding said.

Other future treatment options for C. difficile include developing a more focused, non-absorbable antibiotic that would target the gut and stay there, attacking the C. difficile bacteria while preserving the flora, said Dr. Gerding.

Dr. Classen said he is hopeful about a vaccine strategy, which he expects will move to human testing in early 2009, although Dr. Gerding said it would be "many years" before such therapies are available.