London:  A man of 22 died in agony of dehydration after three days in a leading teaching hospital.

Kane Gorny was so desperate for a drink that he rang police to beg for their help. They arrived on the ward only to be told by doctors that everything was under control.

The next day his mother Rita Cronin found him delirious and he died within hours.

She said nurses had failed to give him vital drugs which controlled fluid levels in his body.

"He was totally dependent on the nurses to help him and they totally betrayed him."

A coroner has such grave concerns about the case that it has been referred to police. Sources say they are investigating the possibility of a corporate manslaughter charge against St George's Hospital in Tooting, South London.

Gorny, from Balham, worked for Waitrose and had been a keen footballer and runner until he was diagnosed with a brain tumour the year before his death. The medication he took caused his bones to weaken and he was admitted to St George's for a hip replacement in May last year. The operation left him immobile.

His 50-year-old mother says that he needed to take drugs three times a day to regulate his hormones. Doctors had told him that without the drugs he would die.

Although he had stressed to staff how important his medication was, she said, no one gave him the drugs.

She said that two days after his hip operation he became severely dehydrated but his requests for water were refused.

He became aggressive and nurses called in security guards to restrain him.

After they had left, he rang the police from his bed. Cronin, who is divorced from her son's father Peter, said: "The police told me he'd said, ‘Please help me. All I want is a drink and no one is helping me'.

"By this time my son was confused due to his lack of medication and I think the nurses just ignored him because they thought he was just being badly behaved.

"They were lazy, careless and hadn't bothered to check his charts and see his medication was essential."

The tragedy emerged a week after a report into hundreds of deaths at Stafford Hospital revealed the appalling quality of care given by many of the nurses.

Last week a task force called on nurses to sign a public pledge to treat every-one with compassion and dignity.