NEW TEST CAN DETECT `MAD COW' DISEASE; STILL NO CURE.

Byline: Denise Mann Medical Tribune News Service

Researchers have developed the first test for ``mad cow'' disease and its human form, a fatal neurological disorder known as Creutzfeldt-Jakob disease (CJD).

Until now, there has been no way to accurately diagnosis these diseases - collectively known as transmissible spongiform encephalopathies - in the living. Previously, only an autopsy could confirm the diseases.

The new test, which detects a brain protein associated with CJD and mad cow disease called 14-3-3 in spinal fluid, may help doctors establish a CJD diagnosis in people who show signs of dementia, according to a report published Thursday in the New England Journal of Medicine.

CJD, a rare neurological disorder that affects only about one in 1 million people, usually strikes people in their 50s and 60s. People may suffer muscle spasms, lose their balance and develop a dementia that mimics Alzheimer's disease. Once symptoms begin, the destruction of brain cells is swift and unrelenting.

``In patients with dementia, a positive test for the 14-3-3 brain protein in cerebrospinal fluid strongly supports a diagnosis of Creutzfeldt-Jakob disease,'' the researchers concluded.

Mad cow disease, formally known as bovine spongiform encephalopathy (BSE), causes cows to stagger, fall and eventually die. Health officials in Great Britain believe that 12 human cases of a CJD-like illness there were most likely caused by consumption of beef containing the BSE agent.

Sheep and other animals also can be afflicted with forms of transmissible spongiform encephalopathy.

Although no treatment or cure is available for these diseases, ``this is the first test in living subjects to help diagnose these diseases,'' said study author Kelvin H. Lee of the biology division of the California Institute of Technology in Pasadena.

The new test ``can help identify candidates for therapy if some were to become available,'' Lee said.

Up to 90 percent of people with CJD die within a year, according to Dr. Frank Bastian, a professor of pathology at the University of Southern Alabama in Mobile.

While the new test is a step in the right direction, what is needed next is a test that would detect the presence of CJD in someone newly infected with the disease, but who did not yet show signs of dementia, he said.

In the study of 71 people with CJD and 30 animals - cows, sheep and chimpanzees - with transmissible spongiform encephalopathy, the new test identified the 14-3-3 protein in 96 percent of people and 87 percent of animals. Diagnoses were confirmed by brain autopsy after the subjects died.