Most patient visits to GPs or to hospital specialists lead to a diagnosis of an illness or condition which is readily identifiable.
But some people can go for years without a diagnosis of sometimes frightening symptoms, until eventually their complaint is recognised.
In a new campaign launched yesterday, the Rare Disorders Alliance is aiming to draw attention to the difficulties faced by people affected by more than 5,000 rare conditions in this country.
The alliance says many families feel their concerns are undervalued and they complain of late diagnosis, little patient-friendly information, difficulty in identifying experts or centres of excellence, isolation and minimal research activity which might help them.
Frances Walsh, 50, of Baildon, is among one in every 10,000 people diagnosed with the rare, difficult to spot and incurable Stickler Syndrome which progressively damages eyesight and leads to osteo-arthritis.
Her diagnosis was made by a specialist at Bradford Royal Infirmary only 12 years ago in just the second case he had seen in four decades after she was admitted for an operation to remove cataracts.
Mrs Walsh was forced to retire from work five years ago because of the illness which has left her registered partially sighted.
She has difficulty judging distance, leaving her unable to walk further than her garden gate, and has lost all colour vision.
She can no longer read and eventually she will only be able to distinguish between light and dark.
Osteo-arthritis developed last year and will progressively worsen.
The syndrome - probably caused by a defective gene - usually runs in families but in her case there is no history of it and its development remains a mystery.
"I know what is coming and therefore I live for each day," she said.
"When I was told what it was, to be honest it was an absolute relief because I knew what was happening with me.
"I cannot distinguish distances and can only see black and white and grey - it's not very appealing looking at white bananas or black cucumbers.
"I do miss sunsets terribly and I do get down at times but I wouldn't be human if I didn't."
She was now closely involved with the Stickler Syndrome Support Group, attending hands-on studies for health professionals and offering help to other people with the condition, which had proved a big help in knowing she was not alone and better able to accept her situation.
"Since I have found the group I have improved unbelievably," she said.
"My appetite is back to normal, I am sleeping better.
"My confidence has improved as has my ability to unwind.
"It is important to remain positive both for yourself and for your family."
Anyone who would like further information about the Rare Disorders Alliance can call 0171 383 3555. For more information about rare disorders or Stickler Syndrome, call Mrs Walsh on (01274) 531854.
Converted for the new archive on 30 June 2000. Some images and formatting may have been lost in the conversion.
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