Rare case of brain disease

An Auckland patient is the latest person to be diagnosed with the incurable brain disorder Creutzfeldt-Jakob disease (CJD), a condition that became notorious because of its association with Britain's "mad cow disease" outbreak of the mid-1990s.

CJD is a neurological disease in which misfolded proteins in the brain, called "prions", create tiny holes throughout the brain tissue, leaving it resembling a sponge when seen under the microscope.

Victims suffer swift memory loss, dementia, hallucinations and personality change. Some types of CJD occur spontaneously, while others spread through contact with infected tissue.

An Auckland District Health Board spokesman confirmed a patient had been admitted to Auckland City Hospital last month with the "sporadic" form of CJD.

Despite the similar symptoms and name, this form is unrelated to the "variant" CJD (vCJD), which caused the death of more than 160 people in Britain.

Those victims contracted vCJD by eating products made from cattle infected with Bovine Spongiform Encephalitis (BSE), also known as mad cow disease.

Associate professor Martin Pollock, head of the CJD register at the University of Otago, said most people suffering from sporadic CJD die within a few months.

"It's just out of the blue. No one knows why it occurs. The families are devastated. They see grandma, for instance, going to a restaurant one week and not able to go the next week."

Pollock emphasised that the sporadic form does not spread.

"They all want to know if it is infectious, and the answer is no."

About five people die from sporadic CJD each year in New Zealand, and there have been no New Zealand cases of vCJD.

Worldwide, the sporadic form of the disease accounts for 85 per cent of CJD cases.

Doctors face challenges in diagnosing the disease because it presents like dementia, Pollock said, and definitive diagnosis is possibly only after death, by sending brain tissue samples to Australia for testing.

However, neurologists are getting better at picking up likely signs of the disease while a patient is still alive.

A spinal fluid test, an MRI scan and an electrical test of the brain are conducted, and if two of the three tests come back positive, the doctors diagnose the condition as probable.

CJD sparked a health scare in Auckland seven years ago when a 30-year-old woman died of CJD in Auckland City Hospital.

Doctors told 11 children and 32 adults they had a slim risk of contracting CJD because the same sterilised surgical instruments used on the woman were used in their operations.

The prions that cause the spread of CJD can survive temperatures of up to 600C, making sterilisation less effective.

Fewer than 1 per cent of CJD cases are caused by exposure to infected brain tissue.

Sunday Star Times