Kidney dialysis patients suffer rare, life-threatening reaction to hormone shots
Wednesday, February 13th 2002, 12:00 am
By: News On 6
A hormone widely used to treat anemia inexplicably triggered a life-threatening reaction in some kidney dialysis patients and left them needing weekly blood transfusions, French researchers say.
The patients had chronic kidney disease, which causes anemia.
In the past, such patients were traditionally given monthly blood transfusions to give them more oxygen-carrying red blood cells.
But about 3 million patients worldwide are instead getting injections of a genetically engineered hormone that stimulates the growth of red blood cells. The drug, epoetin, is also used to treat anemia in people with cancer and AIDS.
Since 1998, more than three dozen European kidney patients given epoetin initially saw their anemia disappear, then return and become life-threatening within three months to five years. They needed weekly blood transfusions to survive.
In Thursday's New England Journal of Medicine, researchers led by Dr. Nicole Casadevall of the Paris hospital Hotel-Dieu studied 13 British and French patients for an explanation.
After eliminating many potential causes, the researchers concluded the patients' immune systems had created antibodies that neutralized both the synthetic hormone and the small amount of natural hormone still made by their kidneys. That halted virtually all production of red blood cells, a potentially fatal condition called aplasia.
But why the patients developed the antibodies was not clear, Casadevall said.
She stressed that the reaction is still extremely rare and patients taking epoetin felt better than they did when they relied on transfusions.
Only one such reaction has been reported in the United States, where kidney patients use a different _ but biologically equivalent _ brand of epoetin, called Epogen, said Jeff Richardson, spokesman for Amgen, the manufacturer.