Belgium banned the herb in the 1990s after it discovered that Aristolochia fangchi caused permanent kidney failure in dozens of people. When cases of kidney and urinary tract cancer began appearing, Belgian doctors advised patients to undergo surgery to remove their kidneys and ureters, the tubes that drain the urine.

Dr. Joelle Nortier, of Brussels's Hospital Erasme, examined the kidneys from 39 people -- who were healthy prior to taking the unnamed weight-loss product--and found cancer in 18 of the patients.

The Nortier group also found that the more Aristolochia fangchi the patient consumed, the greater the likelihood of having a tumour.

"Our findings reinforce the idea that the use of natural herbal medicine may not be without risk," they concluded.

Kessler, now a professor at Yale University's Medical School, said in an accompanying editorial that because "there is virtually no control over the quality of these products (in the United States), it is not unusual not to know what is actually in herbal preparations and dietary supplements."

"Congress has shown little interest in protecting consumers from the hazards of dietary supplements, let alone from the fraudulent claims that are made," he said.

Congress also allows the FDA to act "after the fact and after substantial harm has already occurred," he wrote.

MS: Multiple sclerosis, a debilitating nerve disease that affects more than 2.5 million people worldwide, could actually be four different diseases, researchers said on Wednesday.

Test results from more than 80 different MS patients showed their symptoms, although similar, resulted from four different causes, Dr Hans Lassmann of the University of Vienna in Austria and colleagues said. Researchers still aren't sure what those causes are, although they speculate they may include viruses or autoimmune disorders.

This is important news, they reported in the Annals of Neurology, because treatments that may aid one patient could be harmful to another.

"Besides the current anti-inflammatory and immunomodu-lating treatments, therapies must be tailored towards the needs of specific patient subgroups," Lassman said in a statement.

Multiple sclerosis is caused when myelin, the fatty substance that protects the nerves, is damaged or dstroyed and replaced with scar tissues.

Breast cancer: Women with genetic mutations that increase their risk of developing breast and ovarian cancer are choosing to have the organs removed to prevent the disease, Dutch researchers said on Friday.

DNA tests can determine if women with a family history of breast and ovarian cancer have mutations in the BRCA 1 and BRCA 2 genes. Mutations can increase a woman's lifetime risk of breast cancer by 55 to 85 per cent and ovarian cancer by 15 to 65 per cent.

Researchers at the Rotterdam Cancer Institute, who studied 682 people from 53 Dutch families with a history of cancer, found that women with no symptoms of cancer wanted genetic testing and many who had th emutations opted for surgery.

"We show a high demand for BRCA 1 and BrCA 2 testing by unaffected women at risk, and of prophylactic surgery by unaffected women with the mutation," said Professor Jan Klijin.

Infertility: Women infected with the AIDS virus have just as much right to infertility treatments as other women, two New York doctors argue in the Thursday's New England Journal of Medicine.

Melbourne's department of obstetrics and gynaecology conclude that the human immuno-

It is "evident that the refusal to offer (infertility) services to women with HIV infection may represent a selective application of ethical principles," wrote Drs HOward Minkoff of Maimnides Medical Centre and Nanette Santoro of the Albert Einstein College of Medicine, both in New York City. (Rtr).

AIDS Virus: Circumcised men face less risk of catching the AIDS virus than their uncircumcised counterparts, according to Australian research published in Saturday's issue of the British Medical Journal (BMJ).

The cells are located ona the inside of the foreskin and are exposed during coitus.

The foreskin is also vulnerable to inflammatory lesions, caused by intercuourse or sexually-transmitted disease, that open up a pathway to HIV infection, they say.

Migraine drugs available in US (Sufferers don't care)

BETHESDA, Md, June 9, (Rtr): Powerful new treatments for migraine are available and even better ones should come soon but only about half of all sufferers in the United States ever see their doctors about the problem, specialists said on Thursday.

The said new understanding about the causes of migraine should make it easier to come up with treatments that can stop the debilitating headaches before they even start.

Currently, only 3 per cent to 5 per cent of migraine sufferers get drugs to prevent their headaches and about half stop seeking care, partly because they are dissatisfied with their therapy, the National Institute of Neurological Disorders and Stroke (Ninds), one of the National Institutes of Health, said.

Ninds sponsored a conference in Bethesda on the subject.

"Pain and headache is a brain disorder and we want it to be recognised as such and we want to drive efforts to find a more effective therapy," Dr Gerald Fischbach, head of the Ninds, told a news briefing.

A recent survey of doctors conducted by the World Health Organisation (WHO) placed an acute migraine attack in the highest category of disabling illnesses.

"According to WHO, the folks who worry about AIDS in Africa and tuberculosis around the world, the four most disabling conditions are quadriplegia (being paralysed from the neck down), active psychosis, dementia and severe migraine," Dr Richard Lipton of the Albert Einstein school of medicine in New York told the briefing.

"According to WHO, having amigrine is as bad as being paralysed from the neck down," said Lipton, a co-chair of the conference.

And many people have it -- 28 million Americans -- 18 per cent of women and 6 per cent of men. "It's most commo between the ages 25 and 55," Lipton said.

"Because it affects people during their peak productive years, much of the impact of migraine is in the workplace. It costs American employers $13 billion a year in the form of missed work, absenteeism and reduced productivity of work."

Yet half of all people with migraine do not seek medical care. "Many people with migraine have the mistaken belief that they have sinus headache or stress headache," Lipton said.

"There is a large segment of migraine sufferers who experience high levels of pain and disability who would benefit from better medical care and don't get it," he added.

"There is a gap between what is available and what is delivered. That gap is a significant public health problem."