Describe malingering and fabricated or self-inflicted injuries with their detection.

Definitions

• The essential distinction is between deliberate and unconscious production, and between external and internal gain. Malingering is deliberate with external gain; factitious disorder is deliberate with internal gain; conversion is neither deliberate nor for gain
• Common motives for malingering — compensation after an accident or industrial injury; escaping military or other duty; avoiding work; obtaining a lighter sentence or bail, or transfer from prison to hospital; obtaining drugs; supporting a false criminal charge; and evading a court appearance or an examination
• Commonly feigned conditions — low back pain, headache, ophthalmic complaints and blindness, deafness, epilepsy, paralysis and weakness, aphonia, insanity, haemoptysis and haematuria, and artificial bruising and skin lesions

Detection

• Inconsistency is the central finding — between the history and the examination; between the symptoms and any recognised disease pattern; between the patient's account on different occasions; and, most valuably, between behaviour when observed and when the patient believes they are unobserved
• Prolonged and repeated observation, preferably as an inpatient and by nursing staff rather than by the doctor at set times, is the most productive method
• The symptoms do not fit anatomy or physiology — a sensory loss ending in a straight line, weakness that gives way in a ratchety manner, a "paralysed" limb that does not fall onto the face when dropped, or a claimed total blindness with normal pupillary responses and intact optokinetic nystagmus
• Objective tests do not corroborate — normal nerve conduction, evoked potentials, imaging and biochemistry in the presence of gross claimed deficit
• The response to treatment is atypical, and improvement follows the resolution of the external issue rather than the treatment
• The examination should be thorough and repeated, and organic disease must be excluded properly — the risk of missing genuine illness is much greater than the risk of being deceived

Self-inflicted and Fabricated Injuries

• These are injuries produced by the person themselves, or with the help of another, to support a false accusation — typically of assault or of attempted robbery — or to obtain compensation, or to avert suspicion from themselves
• Characteristic features — situated on parts easily reachable by the person's own hand, and therefore on the front and left side in a right-handed person; sparing vital, sensitive and inaccessible areas — the eyes, the nipples, the genitals, the back and the back of the head; multiple, superficial, parallel and of uniform depth, since the person controls the force; all of the same age; not corresponding to any damage on the clothing, which is often removed or arranged first; and inconsistent with the alleged weapon or account
• The account is usually elaborate and improbable, the person is unusually composed, and there are often no defence injuries despite an alleged struggle
• The distinction from genuine injury rests on the whole pattern, not on any single feature; a genuine assault may occasionally produce a similar distribution, and an opinion should be expressed cautiously
• Suicidal hesitation cuts — multiple superficial tentative cuts beside a deeper one, on the wrist, front of the neck or precordium — are separated from fabricated injuries by intent, and usually by pattern as well

Applied Aspects

• Exclude organic disease thoroughly before considering malingering; follow-up studies repeatedly show organic illness later emerging in patients dismissed as feigning, and the reputational and clinical cost of that error is far greater
• Do not confront or accuse; it is not the doctor's function to expose the patient, it destroys any therapeutic relationship, and it invites a complaint. Record the findings objectively and let them speak
• Record the inconsistencies factually — what was observed, when, and by whom — without characterising the patient; "walked unaided to the toilet at 0230, observed by staff nurse" is evidence, whereas "clearly malingering" is an opinion that will be attacked
• Describe self-inflicted injuries by their features and state that they are consistent with self-infliction, giving the reasons; a bare assertion is worthless in court and a reasoned one is difficult to dislodge
• Remember factitious disorder and conversion disorder are illnesses requiring psychiatric referral, not moral judgement; and that Munchausen syndrome by proxy is child abuse requiring child protection action
• Be cautious in compensation cases, where both over-diagnosis and under-diagnosis carry consequences, and where the doctor's report may be the whole basis of a very large claim