Mysterious Mad Cow-Like Disease Surfaces in Washington State

http://www.tribnet.com/news/local/story/5444054p-5380492c.html

The News Tribune - Tacoma, WA Thursday, August 19, 2004

Mysterious illness resembles mad cow

The Associated Press

Top experts in mad cow-like diseases are trying to identify a strain discovered in a patient at Harborview Medical Center this summer.

It was clearly not the human form of mad cow, nor does it appear to have been Creutzfeldt-Jakob Disease, a closely related condition, said Dr. Pierluigi Gambetti, director of the National Prion Disease Pathology Surveillance Center.

"We really are puzzled at this time," he told The Seattle Times. "This is unusual."

The condition of the patient was not available.

Blood tests conducted over the next few weeks are expected to shed light on the mysterious ailment, said Gambetti, whose Cleveland lab analyzes most of the so-called prion diseases diagnosed in the United States.

Prions are the misshapen proteins thought to cause a family of deadly, brain-wasting diseases that include human forms such as CJD and animal versions such as mad-cow and the lesser-known scrapie.

Scientists say the human form of mad-cow disease, called variant CJD, is probably caused by eating infected beef. The causes of other prion diseases are not well understood.

Preliminary tests on the Harborview patient show that the disease most closely resembles an extremely rare prion disease called GSS (Gerstmann-StraJussler-Scheinker), named after the three German scientists who discovered it.

GSS can be triggered by a dozen different genetic mutations, Gambetti said, and only one of those forms has been shown to be transmissible in laboratory animals.

Invariably fatal, CJD and its close cousins progressively destroy the brains of their victims, robbing them of their memories and their ability to move or speak.

Harborview is reviewing the procedures it used to clean instruments used to take a biopsy from the brain of the mystery-disease patient, since prions are resistant to most ordinary sterilization techniques.

Surgical instruments used on the patient's brain were subsequently used in up to 12 other brain surgeries before being subjected to supercleaning, as the CDC recommends for any instruments used on patients that might have prion diseases.

Harborview officials say two preliminary tests on the patient were negative for CJD, which is the most common human prion disease.

So the hospital used its normal sterilization techniques: soaking the instruments in an enzyme solution, followed by a high-pressure wash and a 272-degree vacuum autoclave.

Two weeks later, when the patient's biopsy results indicated a prion disease was possible, the hospital supersterilized the instruments according to CDC's guidelines, which include an hourlong soak in lye before the high-temperature autoclave.

"We feel confident we followed the recommended national sterilization standards based on the patient's clinical information," said Harborview spokeswoman Susan Gregg-Hanson.

The hospital is reviewing its records to determine whether the patients exposed to the equipment used on the mystery-disease patient should be notified once the ailment is positively identified.

"We need to sit down and review all the facts so we know what to tell people," said Johnese Spisso, Harborview's chief operating officer. "We need to make sure we give them the best information possible so we don't unduly alarm people."

Similar cases over the past few years have raised concern about sterilization techniques in the United States, Canada and the United Kingdom.

Doctors at a Denver hospital operated on six people in 2001 with the same instruments used to take a brain biopsy from a woman who later died of CJD. Two of the patients are suing the hospital.

Several patients settled lawsuits against Tulane University Hospital in New Orleans after eight people may have been exposed to CJD in a similar case in 2000.

In 2001, Madigan Army Medical Center at Fort Lewis closed its operating rooms for two days for extra sterilization after learning a woman who had undergone surgery there four months earlier had CJD.

The hospital notified five people who might have been exposed.

Great Britain, where a mad-cow epidemic wiped out herds and infected more than 100 people, is spending more than $350 million to upgrade sterilization equipment.

(Published 12:01AM, August 19th, 2004)