WEDNESDAY, Feb. 14, 2007 (HealthDay News) -- Adding corticosteroid drugs to conventional treatment for a childhood cardiac illness called Kawasaki disease did not make a difference for most patients, new research shows.
There was, however, a subgroup of high-risk children who seemed to do better with steroids and who deserve further investigation.
"This trial treated all kids to see if overall outcomes could be made better and really they weren't," said study author Dr. Jane Newburger, an associate chief for academic affairs in the department of cardiology at Children's Hospital Boston. "But maybe within this overall group of kids there is a subgroup of the sickest children who could benefit. It's very tantalizing but we can't make a final conclusion about it."
Kawasaki disease, which is reported in about 5,000 children a year in the United States, is characterized by inflammation of blood vessels throughout the body. Symptoms include high fever, rashes, bloodshot eyes, swelling of the hands and feet, redness of the mucous membranes in the mouth, throat and lips, and swollen neck lymph nodes.
The disease and symptoms are treatable with gamma globulin. If treatment is started within the first 10 days, heart damage can be prevented and the patient can make a full recovery. Among patients who don't receive treatment, as many as 25 percent develop lethal coronary problems.
There is no known cause and no diagnostic test. Study of the disease has also been difficult because of problems obtaining tissue and lack of good animal models.
"There's been a tremendous amount of research over the past 30 years looking for specific causes such as viruses, types of bacteria and other infectious agents, and really no single cause has been found," Newburger said.
Standard treatment for the disease is intravenous gamma globulin and aspirin. "This is an extremely effective therapy in most people," Newburger said. "About 10 to 15 percent of children need a second treatment and those who don't respond to gamma globulin really form the highest risk group."
The role of corticosteroids, in addition to conventional treatment, has been unclear.
For this trial, which appears in the Feb. 15 issue of the New England Journal of Medicine, about 200 patients were randomly assigned to receive one dose of intravenous methylprednisolone (a corticosteroid) or a placebo. All patients also received conventional therapy.
After one and five weeks, participants in both groups had similar outcomes, including changes in dimensions of the coronary vessels, numbers of days of fever, rates of re-treatment with intravenous immune globulin, and numbers of adverse events.
However, an analyses conducted later found that children with persistent fever who received gamma globulin as well as the corticosteroid had better coronary outcomes than patients who received re-treatment with gamma globulin and a placebo.
This hints at the possibility that children at high risk for resistance to intravenous gamma globulin and for coronary problems may benefit from receiving corticosteroids, the researchers said.
"We have a small group subgroup of the sickest kids who, in fact, required more than one gamma globulin treatment and had persistent fever," Newburger said. "In that group, there is a suggestion, but not proof, that kids who received steroids did better and had better coronary outcomes. I think where that leaves us is to say that future trials probably should concentrate on the highest risk subgroup with Kawasaki disease."
Find out more on this condtion at the Kawasaki Disease Foundation.