Plasma exchange for unrelenting MS attacks.

It's rare but devastating: an attack of MS that continues to rage despite treatment with high-dose steroids. Over 90% of people having severe MS attacks respond well to steroids, but the few who don't are very ill indeed. Investigators at Mayo Clinic, under the direction of Dr. Brian Weinshenker, studied the effect of a radical measure: shunting the patient's blood through a machine that separates blood cells from blood fluid, or plasma, discarding the plasma, and returning all the blood cells to the patient in an albumin replacement fluid.

The scientists reason that by removing plasma, they remove all the antibodies, immune complexes, activated complement, and immune messenger chemicals it normally carries, thus taming destructive autoimmune activity. It is not proved that plasma exchange really does this. However, the carefully controlled study, which used fake exchanges as a control, but switched patients who didn't respond over to the other group, showed that plasma exchange benefits some people.

The 22 people in the study, 12 of whom had MS, were given a series of 7 treatments every other day for 2 weeks. One-third of the people with MS who got the treatment were considered successes. Almost everyone who got the real treatment developed anemia. The participants were followed for up to 3 years and the successes had no additional MS attacks.

"This offers hope to some people for whom no previous treatment has proven effective," said Dr. Weinshenker when he presented the data at MS Week in Basel, Switzerland. (See page 46.) The 2-hour procedure can be performed at most major medical centers without a hospital stay, but it is considered experimental for MS and may not be covered by health insurance. The cost of 7 treatments is approximately $18,000.

The research was published in the December 1999 issue of Annals of Neurology.