Ingesting the eggs of Trichuris suis, an intestinal worm, appears to be a safe and effective treatment for active Ulcerative colitis, new research shows.

Ulcerative colitis is a common inflammatory disease of the colon that causes bloody diarrhea and heightens the risk of Colon cancer.

Treatment with parasitic worms or “helminths” seems to work by altering the body’s immune system, according to the report in the journal Gastroenterology.

Animal studies have shown helminth therapy to have a beneficial effect on colon inflammation.

In an earlier study, Dr. Joel V. Weinstock, from the University of Iowa in Iowa City, and colleagues described the development of a helminth that cannot multiply within the human body and has no harmful effects. A suspension of the worm’s eggs was given to six patients with bowel disease, and it produced a temporary remission from their disease in all but one.

In the present study, the researchers assessed the outcomes of 54 patients with active ulcerative colitis who were randomly selected to receive Trichuris suis eggs or inactive “placebo” every 2 weeks for 12 weeks.

Forty-three percent of patients in the worm-egg group experienced a moderate or major improvement in their disease compared with just 17 percent of patients in the placebo group.

Only a few patients had complete resolution of their disease and the groups were comparable in this regard.

No side effects or complications were seen in the patients who were given the worm eggs, the investigators point out.

Still, not everyone is ready to jump on the worm bandwagon.

“While there are positive aspects to this trial, the number of patients responding and the depth of the response are modest,” Dr. Lloyd Mayer, from Mount Sinai Hospital in New York, notes in a related editorial. The question still remains whether ingesting worm eggs or any other therapy can truly alter the immune response of an adult patient, he adds.

SOURCE: Gastroenterology, April 2005.