Can C. diff Be Controlled?

Clostridium difficile infections can be stopped before they start or prevented from recurring, potentially limiting bacterial outbreaks linked to 14,000 deaths and $1 billion in extra healthcare costs each year, suggests new research presented last week at the American College of Surgeons' annual conference in Chicago.

Researchers at Massachusetts General Hospital in Boston say intestinal alkaline phosphate (IAP) — an enzyme found naturally in the intestinal lining — keeps intestinal bacteria balanced. Levels of the healthy enzyme drop in sick patients, who, when given antibiotics to treat their illnesses, are also more susceptible to C. diff infections.

To see if oral supplements of IAP could lower infection risks, the researchers put mice on 4-day antibiotic treatments. One group of mice received oral doses of purified IAP. The mice were then injected with C. diff 6 days after receiving antibiotics. Mice that received IAP supplements had 10-fold more C. diff bacteria in their stools, meaning they cleared the toxins in 5 days. Mice who didn't receive the supplement, however, still tested positive.

Humans, like mice, are able to clear C. diff bacteria and related toxins through bowel movements, note the researchers, who believe patients on antibiotics could also take oral IAP supplements to prevent infection.

A second study presented at ACS addressed the high (20% to 50%) recurrence rate of C. diff infections. Researchers at Penn State University College of Medicine say a gene found in C. diff sends signals to stop producing bacteria toxins. When that gene is mutated, however, larger volumes of toxins are produced, which could increase the likelihood of repeat infections.

The researchers were able to isolate the gene in the stool samples of 73 patients between the ages of 50 and 75, the group they say is most commonly diagnosed with C. diff infections. When gene mutations occurred, risk of recurrent infections increased by 80%, according to the study. The findings suggest patients with genetic mutations should receive longer courses of antibiotics to treat C. diff infections and prevent them from recurring.

Daniel Cook