A patient who died after brain surgery at Tulane University Hospital was found to have had a rare, incurable brain disorder that may have been passed on to eight other patients when they underwent operations using some of the same instruments, hospital officials said Thursday.

The illness is Creutzfeldt-Jakob disease. About 6,000 people worldwide each year contract the disease, which results in progressive dementia and loss of physical functions, leaving the brain with holes and a spongelike consistency. The disease is fatal generally within a year of the onset of symptoms. The only definitive way to diagnose the malady is through an autopsy, according to the Creutzfeldt-Jakob Disease Foundation Inc. of North Miami, Fla.

The eight surviving Tulane patients are at risk because the mysterious agent that causes the illness resists standard washing and sterilization procedures, said Dr. Alan Miller, Tulane University Health Sciences Center's vice president for clinical affairs.

The surgical instruments were destroyed as soon as Tulane officials learned of the problem, he said.

The Joint Commission on Accreditation of Healthcare Organizations, which renewed the hospital's accreditation last month for three years, will investigate the incident, commission spokeswoman Charlene Hill said.

She declined to speculate on what the commission might do.

The federal Health Care Financing Administration, which administers Medicare and Medicaid programs, also is studying the death.

Hospital infections are estimated to kill 90,000 Americans every year, according to the federal Centers for Disease Control and Prevention. The toll is growing as disease-causing organisms become increasingly resistant to treatment. By 1995, the CDC said, the rate of hospital infections had increased 36 percent since 1975.

Citing patient confidentiality requirements, Tulane is not releasing the patients' names or the dates of the procedures.

The eight living patients, all of whom underwent brain surgery, are receiving counseling and "related medical care," Miller said in a prepared statement.

There is no reliable way to estimate their risk, he said, or to say when, or whether, symptoms may develop or when their chances of developing the ailment might subside.

Diagnosing Creutzfeldt-Jakob disease is difficult because people in the early stages do not have fever, and sophisticated computer-driven scans do not provide a reliable indication of the illness, according to the foundation.

Initial symptoms include insomnia, depression, confusion, personality and behavioral changes, and problems with memory, coordination and sight. Dementia occurs as the disease progresses, as well as weakness, coordination problems and jerky, irregular movements. In the final stages, the foundation says, patients lose all physical and mental functions and usually slip into a coma.

There is great debate over what transmits the affliction. The current theory is that Creutzfeldt-Jakob disease is spread by a prion, which the foundation defines as "an unconventional agent consisting of protein."

A prion is thought to transform normal molecules into infectious, deadly ones by altering their shapes into dangerous conformations, according to the foundation.

The disease can occur sporadically, without explanation, and it can be inherited. The foundation estimates as many as 15 percent of all cases are inherited.

But the only proven way of contracting Creutzfeldt-Jakob disease is through "an unintended consequence of a medical procedure using tainted human matter or surgical instruments," according to the foundation, which has recorded transmissions during corneal transplants, implantation of electrodes in the brain, the injection of natural human growth hormone from pituitaries of dead people, and grafts of dura mater, a membrane enclosing the brain and spinal cord.

Despite the acute nature of the disease, few cases have come from exposure to infected people, the foundation said, and family members are not at greater risk of developing the ailment.

In Britain, 77 people died from the human form of bovine spongiform encephalopathy, better known as mad-cow disease, which is a variant of Creutzfeldt-Jakob disease. Seven people are still ill from the disease, which was first identified in humans in 1986.More information is available at the Creutzfeldt-Jakob Disease Foundation's Web site, www.cjdfoundation.org.

BATON ROUGE, Louisiana — A Louisiana man who may have been exposed to a rare, fatal brain-wasting disease during surgery is suing the university hospital where his operation was performed, his attorney said on Wednesday.

Michael Rebert, 28, of New Iberia, Louisiana, was told by his neurosurgeon at Tulane University Medical Center in New Orleans last month that he might have been exposed to Creutzfeldt-Jakob disease (CJD) during an operation in April due to contaminated surgical instruments, said lawyer Alicia Hoover of Baton Rouge.

The disease, the human variant of "mad cow disease," causes rapid deterioration of the brain, with progressive dementia and loss of physical functions, medical authorities said. Death usually occurs within a year after the onset of symptoms.

"The irony was that there was a big family debate over whether to have the surgery," she said. "His father, who died just three weeks before the operation, had made him promise to take care of his mother and a younger sister who has cerebral palsy."

Hoover added, "That's why he had the surgery, to be able to hold down a job and care for them," Hoover said.

Although CJD can take years to develop, she said, "More than 50 percent of those exposed to the disease through contamination from infected brain tissue show symptoms of the disease within 0.6 to 2.2 years."

Last month, Tulane confirmed that eight neurosurgery patients may have been exposed to CJD through surgical instruments that may have been contaminated by use on an earlier brain-surgery patient who had the disease.

The hospital said the instruments received routine washing and sterilization after being used on the earlier patient, but admitted that the risk of spreading the disease may not have been eliminated.

CJD was confirmed during an autopsy of the earlier patient, according to a written statement issued last month by Dr. Alan Miller, vice president for clinical affairs at the hospital. The disease can only be determined after an autopsy, he said.

The university on Wednesday refused to release any information not contained in the October statement, which said counseling and follow-up medical care was being offered to the eight patients who may have been exposed.

CJD is believed to be caused by a prion, an unconventional pathogen thought to transform normal protein molecules into deadly ones by altering their shape, authorities said.

Prions are resistant to normal sterilization procedures, Centers for Disease Control and Prevention spokesman Tom Skinner said. Instruments must be treated for an hour in an autoclave, a device used for sterilization employing superheated steam under pressure, at 270 degrees Fahrenheit (132 degrees Celsius) followed by submersion in sodium hydroxide for successful decontamination, Skinner said.

Creutzfeldt-Jakob disease is related to bovine spongiform encephalopathy, better known as mad cow disease, which is thought to be transmitted to humans through the eating of infected beef. At least 70 people in Great Britain have died from the bovine-related illness.

Skinner said the disease is so rare in the United States that it is found in only one in a million people.