Functional symptoms and signs in neurology: assessment and diagnosis

It’s a Tuesday morning at 11.30 am. You are already 45 minutes behind. A 35 year old woman is referred to your neurology clinic with a nine month history of fatigue, dizziness, back pain, left sided weakness, and reduced mobility. Her general practitioner documents a hysterectomy at the age of 25, subsequent division of adhesions for abdominal pain, irritable bowel syndrome, and asthma. She is no longer able to work as a care assistant and rarely leaves the house. Her GP has found some asymmetrical weakness in her legs and wonders if she may have developed multiple sclerosis. She looks unhappy but becomes angry when you ask her whether she is depressed. On examination you note intermittency of effort and clear inconsistency between her ability to walk and examination on the bed. She has already had extensive normal investigations. The patient and her husband want you to “do something”. As you start explaining that there’s no evidence of anything serious and that you think it’s a psychological problem, the consultation goes from bad to worse….

In this article we summarise an approach to the assessment and diagnosis of functional symptoms in neurology, paying attention to those symptoms that are particularly “neurological”, such as paralysis and epileptic-like attacks. In the second of the two articles we describe our approach to the management of functional symptoms bearing in mind the time constraints experienced by a typical neurologist. We also address difficult questions such as: “What causes functional symptoms?”, “Are they real?”, and “Is there anything that can be done?”

We emphasise the need for a transparent and collaborative approach. As we will explain this depends on giving up a purely “psychological” view of functional symptoms in favour of a biopsychosocial view of causation in which dysfunction of the nervous system is the …