WHEN doctors asked Donna Caldwell for a urine sample she filled up the bottle with Irn Bru.

 

She has no memory of the incident but her bizarre actions helped doctors diagnose she was suffering from a rare condition.

Only six people in Scotland are known to have the inherited blood disorder porphyria, which causes chronic pain and mood disorders including mania, depression and hallucinations.

King George III, who was nicknamed 'mad King George', is thought to have suffered from it, as well as at least three other members of the Royal family.

Donna was diagnosed by chance, while she was pregnant, because a student doctor was researching rare diseases.

Both her sons, Andrew, 3 and Oliver, 2, have the condition - there is a 50/50 chance that an affected parent will pass the affected gene to each of their children.

Donna, 32, from Bellshill, realised something wasn't right when she was expecting her first baby at 23. Pregnancy hormones can act as a trigger for the disorder.

She was suffering acute pain and was admitted to hospital but tests could not shed any light on the cause.

She said: "I had had symptoms before that. They thought it might be appendicitis.

"I was in a lot of pain. They checked out the pregnancy and everything seemed to be fine.

"I was doing really bizarre things. They asked me for a urine sample and I poured Irn Bru into the bottle.

"I don't remember doing it but the doctors remember it quite clearly. I was seen by a psychologist.

"Luckily there was a doctor who was doing a dissertation on rare conditions.

"They did more tests and sent it to Cardiff (where one of two UK specialist centres in based) and it came back saying I had acute porphyria."

The porphyrias are a group of disorders where there is a problem with the production of haem, which is used to make haemoglobin in red blood cells.

Symptoms vary greatly and can include abdominal pain, nervous system problems, mental health problems and skin problems.

Rarely, sudden death can occur during an acute attack, due to a disturbance in the electrical activity in the heart.

There is no treatment apart from the administering of blood products, administered in hospital during acute attacks.

At least three member of the Royal family are thought to have suffered from it including Queen Victoria's grandchild Charlotte.

In King George III's time, his bizarre behaviour and wild outbursts were treated as insanity.

The Queen's cousin, William of Gloucester, who died in a plane crash in 1972, was also diagnosed with the condition.

Donna said: "It's like having very bad period pain. There is also the mental health side, I struggle with anxiety and depression and I'm on anti-depressants.

"I know when I'm going to have an acute attack as the pain starts to get worse.

"My husband had to give up work to become my full-time carer but he's now gone back to work. I'm lucky I have family close by.

"I have to live with the fact it's never going to go away."

Sadly Donna's first pregnancy ended in miscarriage. Donna and husband David, 33, were to face more heartache when they suffered two more miscarriages and an ectopic pregnancy. Donna was told by doctors she would not be able to carry a baby to full term because of the condition.

However, against the odds the couple went on to have three children - daughter Libby, 4, Andrew and Oliver.

She said: "To be told you can't have children at 24 was hard to hear. We didn't listen.

"We are adamant that Libby is our wee miracle. Her middle name is Hope.

"When I had the ectopic pregnancy it damaged one of my tubes but she came from the tube that had been damaged.

"The doctors asked us if we had had IVF. They can't explain it."

Donna's sons are closely monitored for signs of the disorder at Yorkhill Hospital. Symptoms are most likely to develop during puberty because of the increase in hormones. However some sufferers may never experience any health problems.

Donna said: "We just pray every day that they won't."

For more information contact the British Porphyria Association at www.porphyria.org.uk