What happens to neurology patients with symptoms "unexplained"?

To be told that your symptoms have no identifiable physical cause can be at once both a relief and a curse. In one sense the doctor is giving you a clean bill of health. But there's the chance they have made a mistake. What's more, if the symptoms persist without explanation, you face the stigma and frustration of people suspecting your problems are "merely" psychological or, worse still, made up. A new study has investigated neurology patients who were told that their symptoms had no identifiable physical cause, following them for a year and a half to see if and how their diagnoses changed.

Jon Stone and his colleagues recruited the help of 36 consultant neurologists working in Scotland's main neurology clinics. Besides a minority of patients who were excluded for being too young or ill, records were kept from nearly all new neurology cases in Scotland between December 2002 and February 2004.

Of the 3781 available patients, around a third were diagnosed as having symptoms that were either "somewhat" or "not at all" explained by physical disease, as opposed to being "largely" or "completely" explained. Of these unexplained cases, the majority were told by their neurologists either simply that their symptoms were unexplained or that they had a headache or that they had conversion symptoms (the physical manifestation of an emotional problem). In a minority of cases, patients were given vague diagnoses such as "pain symptoms" or "fatigue".

Had the story changed much 19 months later? Through contact with the patients' GPs (their primary physicians), Stone's team found just four cases where the neurologist had confidently declared the patient's symptoms as unexplainable, but where an organic illness had subsequently been diagnosed – these were multiple sclerosis, Alzheimer's Disease and two forms of brain lesion.

About 100 other patients had also subsequently received a change of diagnosis, but in most of these cases it was simply that an organic cause that had previously been identified as "somewhat explaining" the symptoms was now seen as the sole cause. In other cases, the initial neurological diagnosis had allowed for the possibility that a physical diagnosis might later be found; a genuinely new condition had emerged; or in some cases, the first neurologist still disputed the subsequent organic diagnosis made by another doctor. There were also five deaths, although these were apparently unrelated to the patients' earlier symptoms.

"New diagnoses that explained the original symptoms rarely emerged over the following 18 months in this study," the researchers said. "Whilst the diagnoses of 'symptoms unexplained by organic disease' must continue to be made with care, the data presented here suggest that serious diagnostic change after an initial clinical assessment by a consultant neurologist is unusual."

Further reading

Stone J, Carson A, Duncan R, Coleman R, Roberts R, Warlow C, Hibberd C, Murray G, Cull R, Pelosi A, Cavanagh J, Matthews K, Goldbeck R, Smyth R, Walker J, Macmahon AD, & Sharpe M (2009). Symptoms 'unexplained by organic disease' in 1144 new neurology out-patients: how often does the diagnosis change at follow-up? Brain : a journal of neurology, 132 (Pt 10), 2878-88 PMID: 19737842