A woman being treated for a brain-wasting condition believed to be related to mad cow disease has died, and an autopsy may help identify the ailment, authorities said.
Brain tissue from the woman will be sent to the National Prion Disease Pathology Surveillance Center at Case Western Reserve University in Cleveland, Washington state health epidemiologist Dr. Jo Hofmann said.
"There will be brain tissue obtained from multiple parts of the brain that will definitely provide more information," Hofmann said.
Results could be at least several weeks away, doctors said.
Hoffman said the woman, who had been treated at Harborview Medical Center in Seattle this summer for dementia and other symptoms, was younger than 60 and neither resided nor died in the state.
Her identify has been withheld at the family's request, and the date of her death was not given in an article published Friday by The Seattle Times.
Medical equipment may have been contaminated
Harborview officials said they would wait for the test results before deciding whether to notify about a dozen patients who had brain surgery after a brain biopsy was performed on the woman and before the instruments used in the surgical procedure were super-sterilized.
Research indicates that ordinary sterilization does not always destroy prions. In very rare cases, prion diseases have been transmitted by contaminated medical equipment.
Tests on the minute amount of brain tissue taken in the biopsy indicated the presence of prions, misshapen proteins that are believed to cause a number of fatal diseases by eating holes in the brain.
Human forms include Creutzfeld-Jakob Disease and a variant in people who have eaten beef from cattle with mad cow disease. Animal forms, besides mad cow, include scrapie in sheep and chronic wasting disease in deer and elk.
CJD and vCJD were ruled out but scientists were unable to make a diagnosis, said Dr. Pierluigi Gambetti, director of the prion center.
"We did all we could, but you can't carry out all the tests on a biopsy," Gambetti said.
Earlier, doctors said the biopsy tests indicated the woman's disease most closely resembles an extremely rare ailment known as GSS, short for Gerstmann, Straussler and Scheinker, the last names of the German scientists who discovered it.
GSS can be triggered by any of a dozen genetic mutations, Gambetti said.
"It could be something new," he added. "This is always a possibility."
Dr. Thomas J. Montine, chief of neuropathology at Harborview, said the larger amount of tissue from an autopsy could solve the mystery.
"The brain is unlike any other organ in the body in that function is highly localized," Montine told The Times in an e-mail. "This means that small lesions in different parts of the brain can have very different clinical outcomes."
