Clinical Caveats for Functional Disorders. Kalpesh Jivan Division of Neurology Department of Neurosciences

Transcription

1 Clinical Caveats for Functional Disorders Kalpesh Jivan Division of Neurology Department of Neurosciences

2 How common are functional symptoms? ± ⅓ of new neurological outpatients

3 Definitions Conversion(functional) disorder: Unintentional Due to emotional stressors No gain to the patient. Factitious disorder(munchausen): Intentional primary or emotional gain Malingering: Intentional, Secondary and often monetary gain

4 Risk factors Young age Female sex

5 Suggestions to history taking Drain the symptoms dry Ask about dissociation Ask what the patient thinks is wrong and what should be done What happened with the other doctors? Go easy on psychological questions Time

6 Psychogenic Non Epileptic Seizures (PNES)

7 Psychogenic Non Epileptic Seizures (PNES) Eyes closed during attack Resistance to eye opening Preserved awareness/memory during bilateral shaking movements Long duration (>5 minutes) Long prodrome (>5 minutes) Weeping during or after a seizure Side to side head movement

8 Psychogenic Non Epileptic Seizures (PNES) Unhelpful features History of tongue biting Injury Urinary incontinence (occurs in syncope, epilepsy and non-epileptic attacks) Attack appearing from 'sleep' Presence of an aura Post-ictal confusion or drowsiness 'Status Epilepticus' (long duration attacks are a red flag for non-epileptic attacks) Alone during a seizure

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10 Motor signs

11 Hoover s sign Sensitivity: 94% Specificity: 99% Hip extension weakness that returns to normal with contralateral hip flexion against resistance

12 Hip Abductor sign Sensitivity: 100% Specificity: 100% Hip abduction weakness returns to normal with contralateral hip abduction against resistance

13 Abduction finger sign Sensitivity: 100% Specificity: 100%

14 Spinal Injuries Centre test Sensitivity: 100% Specificity: 98%

15 Collapsing/Give-way weakness Pt's limbs 'give way' as you test power But be aware of: pain generally ill don't understand the instructions properly Sensitivity: 63% Specificity: 97%

16 Motor variability/inconsistency Discordance in motor testing between two given situations a patient with complete plegia of a limb when tested in a supine position stands on the previously plegic limb and walks out of the examination room. weakness of ankle plantar flexion on the bed but able to walk on tiptoes Inability to move arm during examination, but able to use arm to take something out of a bag or put shoes back on Sensitivity: 13% Specificity: 98%

17 Babinski trunk-thigh test Not validated Supine pt puts arms across chest and tries to sit up Organic paresis: the paretic limb raises above the bed and the contralateral shoulder comes forward Functional paresis: no asymmetry is seen

18 Sensory signs

19 Midline splitting Sensitivity: 20% Specificity: 93% Hemisensory loss split down the middle

20 Splitting of vibration sense Sensitivity: 95% Specificity: 14% Patients can report a difference in the sensation of a tuning fork placed over the left compared to the right side of the sternum or frontal bone

21 Non-anatomical Sensory loss Sensitivity: 74% Specificity: 100% Diminished sensation fitting a nondermatomal pattern Truncal deficits that have only an anterior level but not posterior level Sharply demarcated boundaries at the shoulder or at the groin Strictly unilateral glove or stocking loss Involvement of only half a limb

22 Inconsistency and changing pattern of sensory signs Inconsistency and non reproducibility of sensory signs in repeated sensory testing Reduced joint position sense with normal Rombergs Sensitivity: 79% Specificity: 70%

23 Bowlus-Currier test Not validated

24 Visual symptoms

25 Visual symptoms Fingertip test Signature test Menace reflex Tearing reflex Mirror test Optokinetic (rotating drum) test Tubular visual field defect

26 ENT symptoms

27 Rhinal hypertrophy Not validated Carlo Collodi (1883) Factitious disorder/malingering Described symptom in young boy

28 Pants on fire Not validated

29 Functional movement disorders

30 Functional movement disorders Functional tremor Functional dystonia Functional myoclonus Functional Parkinsonism

31 Functional tremor Most common functional movement disorder Variability Distractability Entrainability Coherence Suggestibility Psychogenic spirals Tremulous gait

32 Functional tremor Variability can present as change in: frequency amplitude direction

33 Variability Direction Frequency

34 Functional tremor Distractability Contralateral finger tapping Recite months backwards No tremor during history taking

35 Distractability Motor tasks Mental tasks

36 Functional tremor Entrainability Ask pt. to flex and extend the wrist of opposite hand at various frequencies

37 Functional tremor Suggestibility Apply tuning fork to the affected body part and suggest that it may alter the tremor

38 Functional tremor Psychogenic spirals Deliberate pauses Portions of figure vary in amplitude and direction

39 Functional dystonia Inconsistent dystonic movements over time Dystonia presenting as a fixed posture or a paroxysmal disorder Presence of incongruous dystonic movements and posture (facial grimacing with pulling mouth to one side) Excessive slowness Marked resistance to passive movements Multiple somatisations

40 Inconsistent character of the movements Associated functional symptomatology Marked reduction of myoclonus with distraction Exarcebation and relief with suggestion and placebo Spontaneous periods of remission Acute onset and sudden resolution Functional Myoclonus

41 Functional gait disorder

42 Pyramidal weakness: Circumduction

43 Dragging Monoplegic Gait Sensitivity: 8.4% Specificity: 100%

44 Chair test Sensitivity: 89% Specificity: 100% Pt is seen to propel a swivel chair better than walking

45 Other Functional gait disorders Fluctuation Excessive slowness Psychogenic Romberg Walking on ice Non-economic posture Sudden knee buckling Astasia-abasia Expressive behaviour

46 Python M. et al

47 Thank you