Missing misdiagnosis

Misdiagnosis of acute illnesses and chronic conditions is the largest cause of preventable medical error and accounts for over 40 per cent of medical malpractice claims in Britain. The National Patient Safety Agency does keep figures of diagnostic errors made in NHS hospitals but underreporting is common. In 2014, the NHS paid out £194 million in compensation to 1,302 patients or bereaved families whose illnesses or conditions were misdiagnosed. About one in ten payouts went to patients whose cancer had been missed.

So what is going wrong? Most experts agree that misdiagnosis is a problem with many causes, but GPs have a huge amount of responsibility as the gatekeepers of healthcare. Also, cheap and simple tests which can distinguish different diseases should be offered as a matter of routine.

Professor Dame Jessica Corner, chief clinician at Macmillan Cancer Support, agrees that GPs have to be given the information they need to spot difficult cases. ‘The reason that some cancers are not diagnosed straight away is because the average GP will only see around ten cancer patients in their surgery a year. So this is how cancer can be missed or overlooked. Cancer is also prevalent in those over 65 years, so it might not be the first thing a GP will look for or think of if the patient is of a younger age. So we need to raise awareness of cancer amongst GPs to ensure that people are being referred.’

NICE has issued guidelines that doctors in doubt should always refer to specialists, but this is not always practical. GPs say they are trying to do their best with growing numbers of patients, targets and dwindling resources. Gillian Watson, of the Royal College of General Practitioners, points out that GPs make a million diagnoses every day in the UK and feel beleaguered by criticism directed at them for failing patients. “We are doing extremely valuable work despite difficult circumstances. You have to look at this in the context of what is happening in primary care with extra burdens and responsibilities constantly piled on GPs as the government brings more services into the community.”

It doesn’t help that there is an acute shortage of specialists, including allergy consultants, and neurologists. Waiting lists can be long and mistakes can easily be made as the pressure mounts to clear backlogs.

Professor Mayur Lakhani, a practising GP and former Chairman of the RCGP said: ‘GPs are faced with a lack of specialist support which will make implementation of the guidelines very difficult – there are long waiting lists for outpatients and some patients already face fragmentation of care.’

In the whole of the UK, there are only 30 neurologists with a special interest in epilepsy, a disease that affects one in 131 people in the population. ‘What NICE recommends is often impossible to implement,’ says Amanda Cleaver of the National Society for Epilepsy. ‘Services are very variable in different parts of the country and you may find it difficult to get into a specialist assessment centre.’

Future solutions?

A more holistic approach: 

‘GPs are in a unique position to improve recognition due to the frequency with which they see their patients,’ says Professor Lakhani. ‘Many patients have multiple co-morbidity and the GP’s role is critical to the diagnosis and management of the condition and coordination of care. “Collaboration with specialists is important and we suggest that GPs and consultants work together to improve care.’

Technology is helping to eliminate human error:

Thousands of doctors now use a web-based clinical decision support system, Isabel, which helps them to improve their diagnoses. A study published in the open access journal BMC Medical Informatics and Decision Making said that Isabel had prompted paediatricians to make an important change to their diagnosis in 12.5% of cases analysed. Consulting Isabel added only one minute to the time taken to diagnose, and improved diagnostic accuracy for both easy and difficult cases. Isabel is named after a little girl in the US who was misdiagnosed after she developed necrotising fasciitis as a complication of chicken pox and barely pulled through after two months in a high dependency unit.

Genes:

Using highly sophisticated computer programs that mimic human intelligence, researchers at the University of Maryland Greenebaum Cancer Center in Baltimore devised a new method to differentiate and diagnose several types of colon tumours.

The method, which uses “artificial neural networks,” or ANNs, to analyse thousands of genes at one time, is now helping doctors to identify many cancers earlier and spare some patients from unnecessary, debilitating surgery.