Conversion Disorder (Functional Neurologic Symptom Disorder)

Reported prevalence varies widely (11–500”100,000). It may account for unexplained symptoms in as much as 1–14% of general medical/surgical pts and possibly as much as 20% of new outpatient neurology referrals.

Possibly higher in rural populations, developing areas, lower socioeconomic groups, those less medically sophisticated, and following physical and sexual abuse and trauma.

Hx of conversion disorder may not increase periop morbidity or mortality per se, although the risk may increase for “failure to diagnose” if new symptom complexes are too quickly attributed to conversion disorder.

Presence of undiagnosed cognitive, neurologic, or general medical illnesses and adverse effects of a drug or treatment

Periop appearance of conversion symptoms mimicking medical disturbances, drug effects, or anesthetic or surgically related complications

Malingering disorder, factitious disorder, dissociative disorder, addiction, pseudoaddiction, and withdrawal

DSM-V: Conversion disorder (functional neurologic symptom disorder)—in conversion disorder, a subclassification of Somatic Symptom and Related Disorders is a diagnosis of exclusion made when a pt demonstrates or reports motor or sensory symptoms unexplained by a medical condition.

ICD-10 classifies conversion disorder among dissociative disorders and places more emphasis on disproving a factitious disorder.

Following anesthesia, occurrence of seizures, generalized or focal weakness or sensory loss, and trouble with speaking or swallowing require careful workup even though may also be the presentation of conversion disorder. The amount of medical knowledge held by the pt may predict whether the presenting symptoms closely mimic known medical conditions and may affect the degree to which the pt accurately reproduces the symptoms on serial evaluation.

Different from malingering and factitious disorders, the pt is not consciously generating false symptoms. In isolation, neither report of pain nor sexual dysfunction is sufficient to meet the criteria.

Most common in the second through fourth decades, with initial symptom onset lasting up to 2 weeks, according to the DSM-V, loss of body movement, sight, or speech have better long-term outcome than symptoms of seizure or tremor.

Although the exact etiology is unknown, symptoms may occur as an unconscious solution to trauma or unresolved conflict.

More common in pts with prior medical and psychiatric diagnoses.

Possible genetic predisposition suggested in twin and familial studies.