Dr John Holden, a senior medical adviser at the UK-wide medical defence organisation, said: ‘Although individual rare diseases are by definition uncommon, many doctors will regularly encounter patients with a variety of rare diseases.
‘In order to minimise the risk of overlooking a rare diagnosis it is important to assess patients carefully by means of a full history, an examination and by providing or arranging advice, investigations or treatment and by referring to a specialist when the doctor considers that this would be in the patient's best interests.'
The difficulty in diagnosing rare conditions was highlighted earlier this month by England's CMO Sir Liam Donaldson.
A disease is classed as 'rare' when it affects fewer than five in every 10,000 people. But given that there are more than 6,000 rare diseases, it means that one person in every 17 will present with a rare disease, around three million people in England.
According to the CMO's report, two in five people with a rare disease have reported difficulty in getting a correct diagnosis and accessing the right services and support for themselves and their families.
MDDUS advice is to follow GMC guidance and work within your competence, respect a patient's right to seek a second opinion and seek the advice of colleagues when appropriate.