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Functional or Feigned: a neurological dilemma

Posted in Clinical Dilemmas in Neuropsychiatry on 20th Sep 2012


Richard AA Kanaan

Richard AA Kanaan is a Consultant Psychiatrist at the Maudsley Hospital, Honorary Consultant Neuropsychiatrist at King’s College Hospital and Visiting Senior Lecturer at the Institute of Psychiatry. His special interests include conversion disorder and factitious disorder.

Correspondence to:
Richard AA Kanaan, Consultant Psychiatrist, Dept of Psychological Medicine, Institute of Psychiatry, King’s College London, P062, Weston Education Centre, London SE5 9RJ, UK. Email: Tel: +44 (0)20 7848 0158, Fax: +44 (0)20 7848 5408

Series editor Alan Carson is a Consultant Neuropsychiatrist and Part-time Senior Lecturer. He works between the Neurorehabiltation Units of the Astley Ainslie Hospital and the Department of Clinical Neurosciences at the Western General Hospital in Edinburgh. He has widespread interests in neuropsychiatry including brain injury, HIV and stroke. He has longstanding research and teaching collaboration with Jon Stone on functional symptoms in neurology.

Series editor Jon Stone is a Consultant Neurologist and Honorary Senior Lecturer in the Department of Clinical Neurosciences in Edinburgh. Since 1999 he has developed a research and clinical interest in functional symptoms within neurology, especially the symptom of weakness. He writes regularly on this topic in scientific papers and for textbooks of neurology and psychiatry.

Correspondence to:

Welcome to the twelfth in a series of articles in ACNR exploring clinical dilemmas in neuropsychiatry. In this series of articles we have asked neurologists and psychiatrists working at the interface of those two specialties to write short pieces in response to everyday case-based clinical dilemmas. We have asked the authors to use evidence but were also interested in their own personal views on topics. We would welcome feedback on these articles, particularly from readers with an alternative viewpoint.


A 23-year-old girl with a paraplegia of two years duration has been referred for a second opinion as to whether her symptoms are functional. After appropriate examination and investigation you concur that no organic explanation is possible.  You find her remarkably well adjusted to her condition – indeed she tells you she hopes to represent her country in the Paralympic games.  However, while she is awaiting transport you happen to notice her uncrossing and re-crossing her legs without using her hands, and become concerned that she may be feigning her symptoms.  What should you do?

The relationship between conversion disorder and feigning is not an easy one for many clinicians.  Most neurologists do not see the two as entirely distinct1 and would rather not get involved in the uncomfortable business of distinguishing them. While the limited data we have suggest feigned neurological presentations are relatively rare, it may be difficult to be certain in the clinical setting, and feigning is probably under-diagnosed.3  When faced with neurological symptoms that do not appear neuropathological in origin it is appropriate to presume these represent a conversion disorder rather than feigning, but sometimes, as in the case presented, your suspicions may be raised.  This is an alarming scenario, questioning the clinician’s responsibility to the patient and more widely, and threatening a serious conflict with the patient.  I shall consider these challenges under three questions:  How would I know if a patient with functional symptoms is feigning?  What does it mean if they are?  And, what should I do about it?

How would I know if a patient with functional symptoms is feigning?

The detection of feigned or induced illness is rarely easy. In general medicine, most cases are detected because the methods they have used to feign or induce their illness leave an evidence trail (the culturing of faecal bacteria from a wound that will not heal,), or their methods are observed (putting their thermometer in their cup of tea). Unfortunately,  there are few such exogenous tools needed to feign most neurological illness – all the patient needs is a flair for the theatrical – and consequently the means of its detection is limited, typically to confession or the exposure of some other aspect of their deception, such as a false identity.3  Of course, a patient who feigns weakness is unlikely to convince most neurologists that they have any serious organic pathology for very long – the history and examination alone will probably show a pattern inconsistent with known disease.  But this very same inconsistency is characteristic of conversion disorder.  How could you possibly tell those two apart?

The short answer is you probably can’t – at least not without the sort of help you are unlikely to get in the clinic.  The difference between a conversion disorder and feigning lies primarily in the conscious awareness or intentionality with which the symptoms are produced by the patient.  So, to tell them apart would require finding out what the patient thinks, when they are presumably (if feigning) determined to hide it: whether, if you like, they are lying when they say they can’t move their leg.  And that kind of detection has proven beyond all tested professions, whether military, judicial or clinical.5 Of course, there can be many clues that someone is lying, and sometimes their behaviour can be taken as proof of what they know.  In the medico-legal setting, for example, it is common for private detectives to be hired when a feigned disability is suspected, hoping to catch the patient in an act of exertion incompatible with their avowed limitations.

But caution must be exercised in conversion disorder, since a degree of inconsistency is, again, characteristic, a key diagnostic feature1,6, and quite uninformative about intentionality:  the patient who stands unaided having previously shown zero power at hip extension is very likely to be surprised if you point out the incompatibility, but most unlikely to collapse and admit they were feigning.  To be confident it is feigned, an inconsistency would have to be so obvious that the patient really couldn’t have it without knowing it, such as playing football while claiming paraparesis.  Similarly, other clues to a feigned illness – an obvious benefit or gain to their being ill, a belle indifference to their symptoms, a resistance to investigation, a history that is vague – have also been claimed to a degree for conversion disorder.

So, unless you follow the patient home, recognise them from their previous malingering or elicit a confession, you are unlikely to be certain; but you may well, as in this case, have grounds for suspicion: she does seem unconcerned, she is obviously benefitting, and it would be hard not to realise you’re voluntarily moving your legs when you claim they are paralysed.  But is even a strong suspicion enough?  We shall return to the question of the standard of proof when we consider what to do about it.

What does it mean if they are feigning?

There are several forms that medical deception can take. The most familiar is malingering – feigning for disability benefits or litigation, to evade conscription or prison. Others feign illness for what are thought to be pathological reasons, however – to get the sympathy and care of the sick role – in what is called factitious disorder (of which Munchausen’s Syndrome may be considered a chronic subtype). The difference between the two lies only in whether the motives for the deception are ‘internal’ (such as sympathy) or ‘external’ (such as money) but, importantly, factitious disorder is considered a psychiatric condition whereas malingering is not considered a medical condition at all, merely criminal behaviour. This makes the distinction of vital, legal importance – which may seem unfair, given the vague nature of the distinction.7 Consider our case: does being a paralympian represent an external benefit (fame and success) or an internal one (sympathy and admiration)?8

Deception may mean neither of these things however. It is important to remember that everyone lies at some time or another, and patients are no exception.9 The medical encounter is enormously important for most patients, and they are likely to be strongly motivated to present their case in the most convincing way possible, even if that requires exaggerating or lying to a clinician whom they feel does not take them sufficiently seriously.10  A single act of deception does not mean the whole performance is a sham. Equally, many clinicians have wondered whether the conscious/subconscious boundary for conversion disorder is entirely fixed: whether a patient with a subconscious paralysis may not gain conscious control yet stick with the presentation as it has proven useful or face-saving; or a patient with a feigned paralysis come to believe in it and its maintenance then become automatic.  Again, a single moment of conscious awareness does not necessarily mean it was always so.  For these reasons, among others, the distinction is thought by some to matter less clinically than it undeniably does legally or to the patient or their family.7

But are they, if considered feigning, even your patient any longer? If a malingerer does not have an illness, are they even a patient, or just someone pretending to be a patient?11  There are at least two issues here: there is the fraud that may have been practised on you, and the question of their medical care.  With regards to the fraud, you may well feel very aggrieved; with regards to their medical care, you may well feel it is no longer your responsibility.1  In either case you are likely to wish to be rid of the patient, and to warn others off; but caution is needed here, more than anywhere.

What should I do if they are feigning?

There are real dangers in the management of medical deception.  The patient has tried to trick you, and your desired response may be to punish them and save the world from them.  But it is not a fair fight.  You, unlike the patient, have a duty of care; you, unlike the patient, can’t break confidentiality.

If the patient has behaved so badly you cannot contemplate treating them further, you may wish to have nothing further to do with them.  But your responsibilities as a doctor do not end simply because the patient is not honouring their side of the medical contract.  They remain a patient of yours as long as they are under your care – even if (as for many other patients) it turns out there is nothing wrong with them.  You may discharge them if you feel your relationship has been irretrievably damaged, of course, but to whom, and how?

With a malingerer it may not seem necessary for anyone to take over their care, and to discharge back to the GP; for a factitious disorder it may be appropriate for a psychiatrist to be involved. But any letter you write will come up against the barrier of confidentiality: you cannot tell anyone anything the patient does not want you to say without their consent (unless there is the risk of serious harm to someone else, or they lack capacity to consent).  With other health professionals, such as their GP, there is an implied consent for disclosure, yet in such a situation, where you think it likely the patient will not want something disclosed, the onus would be on you to tell the patient what you are planning to write – at which point it is likely they will withdraw their consent. The contents of the letter will have to be negotiated and agreed with the patient, painful as that may be. Equally, with agencies such as the benefits agency (or the Paralympics Committee): you are obliged to tell the truth if asked, but you cannot make spontaneous disclosure and cannot disclose anything to which the patient does not consent.

There is no such restriction on your medical notes – indeed it is paramount that you keep a full and contemporaneous record, as the chance that this will be drawn upon is considerable.  A second opinion is a very good idea, for the same reason: there is strength in numbers if your opinion is ever challenged. For the risks you face in reaching such a view are, in addition to a very uncomfortable patient encounter, being sued by the patient, and being referred to your medical licensing authority.  Here, at least, there is some comfort, for the diagnostic standards to which your behaviour will be held in court are (in the UK at least) those of a responsible body of medical opinion; for the licensing authority (in the UK at least) they are likely to be lower still.  If your suspicions are those you think a responsible body of fellow neurologists share with equal strength, then the law is likely to find in your favour should your care be legally challenged; but that may be scant comfort for the other challenges you will have faced along the way.

So, finally, what would I do in this case? Given the risks, doing the right thing will take courage, but here, alas, it’s not even clear what the right thing to do is.2  Though I have given only a bare clinical outline, this accurately reflects the conditions of uncertainty under which we are likely to operate.  Simply put, I don’t know if this lady is feigning but I think it’s a strong possibility; moreover, other than by what may emerge from a discussion of this with her, I see no clear path to deciding it one way or the other.  So on balance, if I were feeling sufficiently brave that morning, I would have the discussion.  I would tell the patient what I’d seen, and what it could mean.  I would tell them that my differential diagnosis included both conversion disorder and feigning, and would wait – with bated breath – for her response…


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