Functional neurologic disorder (previously termed conversion disorder) and somatic symptom disorder are both characterized by somatic symptoms associated with significant distress or impairment.
The underlying cause is not fully understood. Although psychological stressors can be important risk factors and may perpetuate symptoms, they are not necessary to make the diagnosis.
Functional neurologic disorder can be diagnosed on the basis of positive "rule in" features on neurologic examination - it is no longer considered a diagnosis of exclusion.
Good therapeutic alliance, validation of the patient's suffering, and shared clinician-patient understanding of the condition are essential for effective management.
Treatment includes cognitive behavioral therapy, physical therapy, and avoiding unnecessary medicines, tests, and procedures. Diagnosis and treatment of associated comorbid psychiatric conditions can benefit overall functioning and recovery.
This topic describes diagnosis and management of functional neurologic disorder and somatic symptom disorder in adults only; diagnosis and management in children is beyond its scope.
Functional neurologic disorder (previously termed conversion disorder) and somatic symptom disorder are (neuro)psychiatric conditions that fall under the somatic symptom and related disorders category of the Diagnostic and Statistical Manual of Mental Disorders, 5th edition, text revision (DSM-5-TR) (previously termed somatoform disorders). Somatic symptom and related disorders are those with prominent physical symptoms associated with significant distress and impairment of function.
Functional neurologic disorder is characterized by motor or sensory function deficits that suggest neurologic or medical conditions associated with characteristic "rule in" features on neurologic examination and clinically significant distress or social/occupational impairment. Somatic symptom disorder is characterized by one or more somatic symptoms that are distressing or result in significant disruption of daily life. To meet DSM-5-TR criteria, these patients must have excessive thoughts, feelings, or behaviors related to the somatic symptoms or associated health concerns as manifested by at least one of the following: disproportionate and persistent thoughts about the seriousness of one’s symptoms; persistently high levels of anxiety about health or symptoms; excessive time or energy devoted to these symptoms or health concerns. Importantly, even if any one somatic symptom is not continuously present, the state of being symptomatic is persistent (typically more than 6 months).
History and exam
Key diagnostic factors
- unconventional behavior during history
- emotional processing problems
- recent psychological or physical stressors
- remote life stressors
- multiple illness behaviors
- unusual neurologic deficits
- give-way weakness
- inconsistent examination findings
- paradoxical sensory findings
- distractible symptoms
- generalized seizure-like motor movements without loss of awareness
- gait disorders
- functional movement disorders
Other diagnostic factors
- cognitive complaints
- Hoover sign
- speech disturbance
- swallowing disturbance
- convergence spasm
- history of sexual or physical abuse
- adverse childhood events
- history of trauma-related disorders
- female sex
- previously poor doctor-patient relationships
1st investigations to order
- laboratory testing
- electroencephalogram (EEG)
Investigations to consider
- comprehensive neuropsychological testing
- standardized personality testing
- focused symptom inventories
functional neurologic disorder
somatic symptom disorder
- Illness anxiety disorder
- Body dysmorphic disorder
- Factitious disorder
- A review and expert opinion on the neuropsychiatric assessment of motor functional neurological disorders
- Evidence-based practice for the clinical assessment of psychogenic nonepileptic seizures
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