Functional Neurological Disorder (Conversion Disorder) - Episodic Unconsciousness in a Teenage Girl

What is This?

"Approximately 20% of [dissociative] attacks resemble syncope more than epilepsy and consist of the patient falling down and lying still with their eyes shut for more than 2 minutes." - Bradley & Daroff's Neurology in Clinical Practice

Key Epidemiology - Why a Teenage Girl?

• Peak age of onset: late teens (mean mid-20s overall)
• Female predominance: 3:1 over males
• FND can occur in children as young as 7-8 years; it is rare after age 35
• Comprises 5-14% of medical/surgical psychiatric referrals in general hospitals

DSM-5 Diagnostic Criteria (Conversion Disorder / FND)

1. One or more symptoms of altered voluntary motor or sensory function (including consciousness/awareness)
2. Positive evidence of incompatibility between the symptom and recognized neurological or medical disease (e.g., on examination)
3. The symptom is not better explained by another medical or mental disorder
4. The symptom causes clinically significant distress or functional impairment

Clinical Features of Dissociative Unresponsiveness in a Teenager

• Falls down and lies still with eyes closed (eyes open during true epileptic seizures or genuine syncope)
• Lasts longer than 2 minutes of unresponsiveness (syncope rarely exceeds 30-60 seconds)
• No tonic-clonic jerking OR - thrashing, side-to-side head movements (distinct from epileptic motor patterns)
• No postictal confusion afterward (epilepsy typically has a postictal phase)
• Prolactin level: NOT elevated after event (elevated in epileptic seizures)
• EEG during attack: no epileptiform activity
• Gradual onset vs. sudden collapse of epilepsy/syncope
• May recall some awareness during the attack as she recovers

Differential Diagnosis - Must Rule Out First

Etiology and Pathophysiology

• Behavioral theory: faulty childhood learning, with non-adaptive responses used for secondary gain and control of interpersonal relationships
• Psychoanalytic theory: symptoms represent compromise formations (conflict resolution) without conscious awareness
• Some association with childhood trauma (physical or sexual abuse), though this is not universal
• Panic disorder is the single most common comorbid condition - dissociative attacks may be a variant of panic attack where the patient dissociates rather than consciously experiencing anxiety

• School exams/performance pressure
• Family conflict
• Bullying or social rejection
• Sexual or physical abuse (ask carefully, not bluntly)

Investigations

1. Video-EEG during a captured event - gold standard (no epileptiform activity during attacks)
2. MRI brain - normal
3. Basic labs: glucose, electrolytes, calcium, CBC, thyroid function
4. Anti-NMDA receptor antibodies (serum and CSF) - mandatory in teenage girls
5. ECG + cardiac monitoring - rule out long QT, arrhythmia
6. Prolactin (15-20 min post-event) - NOT elevated in FND attacks
7. Neuropsychological testing if cognitive symptoms coexist

Management

1. Delivering the Diagnosis (Most Critical Step)

• Explain the diagnosis positively, not as "there is nothing wrong" but as "your nervous system is not working as it should, but there is no damage"
• Use the terms "functional disorder" or "dissociative attacks" - avoid "psychogenic" or "hysterical"
• Acknowledge the symptoms are real and not consciously produced
• Do NOT accuse or imply malingering - this is profoundly counterproductive
• Address the patient's beliefs about irreversibility - studies show beliefs about irreversibility predict outcome better than age, disability, or distress level

2. Psychological Treatment (First Line)

• Cognitive Behavioral Therapy (CBT) - the method of choice
• Treat comorbid panic disorder, anxiety, or depression
• Address underlying stressors (school, family, abuse history)
• Family therapy - especially important in adolescents
• Avoid confrontational approaches; use empathic, face-saving reframing

3. Physiotherapy

• Graduated physical rehabilitation for motor symptoms
• Helpful even in episodic unresponsiveness (improves overall function and reduces attack frequency)

4. Pharmacological

• No specific medication for FND itself
• Treat comorbid anxiety/depression: SSRIs (e.g., sertraline, fluoxetine)
• Antidepressants can reduce attack frequency indirectly through comorbidity treatment
• Benzodiazepines should be avoided long-term

5. School/Social Support

• School liaison to manage absences and reintegration
• Reduce academic pressure during recovery
• Social support from teachers and peers

Prognosis

• Strong beliefs in irreversibility of symptoms
• Anger at or rejection of the diagnosis
• Delayed diagnosis
• Multiple physical symptoms / comorbid somatization
• Concurrent organic disease
• Personality disorder, older age, history of sexual abuse
• Ongoing disability compensation

• Early diagnosis and explanation
• Acute onset (short history)
• Good therapeutic alliance
• Absence of severe comorbid psychiatric disorder

Key Points to Remember

• This is NOT malingering or a behavioral/willful disorder
• It is NOT "nothing wrong" - it is a disorder of nervous system function
• Stress is a risk factor but is not required for the diagnosis
• Approximately 1/3 of patients have no depression or anxiety - do not dismiss the diagnosis just because the teenager appears psychologically normal
• Anti-NMDA receptor encephalitis must be excluded in any teenage girl with episodic altered consciousness
• The goal is a positive, biopsychosocial explanation that empowers recovery

• Bradley and Daroff's Neurology in Clinical Practice, Chapter 113 (Functional Neurological Disorders)
• Kaplan and Sadock's Synopsis of Psychiatry, Chapter 12 (Conversion Disorder/FND), pp. 1385-1414
• Rosen's Emergency Medicine, p. 2303-2304
• Harrison's Principles of Internal Medicine 22E (Functional Neurological Disorders)