A WOMAN suffered a life-threatening reaction after being given blood from another patient with a peanut allergy.
It is believed to be the first time a severe food allergy has passed from one person to another through donated blood.
The incident, reported in a medical journal, has prompted calls for blood donors to be rigorously screened for allergies.
The 80-year-old patient was given blood ahead of minor surgery to investigate stomach problems.
Two days later she ate a muffin with peanut butter and became ill within minutes with anaphylactic shock. Her throat closed, she was struggling for breath and she had difficulty swallowing.
Doctors immediately injected her with adrenaline and steroids to halt the potentially fatal reaction.
When they checked the records, they found the blood had come from a 19-year-old female patient with a history of severe allergic reactions to nuts.
"We need to consider whether we should screen blood donors for allergy," said Dr Donald Arnold, of the department of medicine at McMaster University in Canada, where the woman was treated. The incident was reported in the Archives of Internal Medicine.
Allergies to peanuts and other foods have increased sharply in the UK in recent years. About one million people are now thought to be affected, mainly children.
A study is under way at the Norwich-based Institute of Food Research to investigate the problem.
The National Blood Service said it does not test donated blood for allergies.
Allergy sufferers are allowed to give blood as long as they are not suffering any symptoms on the day.