Crohn’s disease is common in countries where infection with intestinal parasites is rare, but uncommon in countries where it frequently occurs, Dr. Joel Weinstock and his colleagues explain in the journal Gut.

T. suis is not a natural human parasite, but primary affects pigs. The eggs of this parasite can infect the human gut for a short time without spreading to other parts of the body, the researchers explain.

Using this information, Weinstock’s group enrolled 29 patients who had moderately severe Crohn’s disease that did not respond to standard treatment for inflammatory bowel disease.

Every three weeks, patients consumed a commercial drink containing 2500 ova of this parasite, while all their other medications were held constant.

Four patients withdrew by week 12 because of ongoing activity of Crohn’s disease and one patient withdrew because of pregnancy.

In remaining patients, by week 24, almost 80 percent showed a response to treatment and about 72 percent were in Crohn’s disease remission.

The treatment appeared to be free of side effects or complications, and none of the patients developed new symptoms during the trial.

“We think that this treatment works by enhancing regulatory aspects of the immune system,” Weinstock told AMN Health.

In fact, treatment was so effective that it is “being explored as a possible therapy for multiple sclerosis, asthma, allergic rhinitis, and other immune diseases,” he added.

Weinstock also cautioned, however, that this was a small, open-label trial, and further study is required before this treatment can be recommended.

SOURCE: Gut, January 2005.