AUTHOR AND EDITOR INFORMATION

Section 1 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

INTRODUCTION

Section 2 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

Background

Psychogenic nonepileptic seizures (PNES), or pseudoseizures are paroxysmal episodes that resemble and often misdiagnosed as epileptic seizures; however, PNES are psychological in origin.

Paroxysmal nonepileptic episodes can be either organic or psychogenic. Syncope, migraine, and transient ischemic attacks (TIAs) are examples of organic, nonepileptic paroxysmal symptoms. This article covers only PNES.

The terminology on the topic has been variable and, at times, confusing. Various terms are used, including pseudoseizures, nonepileptic seizures, nonepileptic events, and psychogenic seizures. PNES is the preferred term and the one used throughout this article.

PNES are common at epilepsy centers, where they are seen in 20-30% of patients referred for refractory seizures. PNES are probably also common in the general population, with an estimated prevalence of 2-33 cases per 100,000 population, which makes PNES nearly as prevalent as multiple sclerosis or trigeminal neuralgia.

Pathophysiology

Unlike epileptic seizures, PNES do not result from an abnormal electrical discharge from the brain; they are a physical manifestation of a psychological disturbance. They are a type of conversion disorder or, more broadly, a type of somatoform disorder, and they are usually involuntary. PNES can also result from voluntary faking (feigning), as in malingering and factitious disorder. This cause is thought to be rare, but it is difficult to prove.

Frequency

United States

PNES are commonly misdiagnosed as epilepsy. It is by far the most frequent nonepileptic condition seen in epilepsy centers, where they represent 20-30% of referrals. About 50-70% of patients become seizure-free after diagnosis, and about 15% also have epilepsy. Like most manifestations of conversion and other somatoform disorders, PNES occur more frequently in women (approximately 70% of cases) than in men.

International

The international prevalence is similar to that in the United States.

Sex

Like most manifestations of conversion and other somatoform disorders, PNES occur more frequently in women (who account for approximately 70% of all cases) than in men.

Age

PNES, similar to conversion disorders, typically begin in young adulthood.

PNES occur in children and adolescents and also in elderly people.

• One should be particularly cautious in diagnosing PNES (and psychogenic symptoms in general) when the onset is in early childhood or old age.
• In these age groups, nonepileptic physiologic events may be more common than other conditions.
• For example, children may have parasomnias (eg, night terrors), breath-holding spells, and shuddering attacks.

CLINICAL

Section 3 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

History

Misdiagnosis of epilepsy is common. Misdiagnosis occurs in approximately 25% of patients with a previous diagnosis of epilepsy that does no respond to drugs. Most cases of misdiagnosed epilepsy are eventually shown to be PNES or, more rarely, syncope. Other paroxysmal conditions are occasionally misdiagnosed as epilepsy, but PNES is by far the most commonly misdiagnosed condition, accounting for >90% of misdiagnoses at epilepsy centers. EEGs interpreted as providing evidence for epilepsy often contribute to this misdiagnosis (Benbadis, 2003).

Reversing a misdiagnosis of epilepsy can be difficult, as it is with other chronic conditions. Unfortunately, after the diagnosis of seizures is made, it is easily perpetuated without being questioned, which explains the usual diagnostic delay and cost associated with PNES. Despite the ability to diagnose PNES with near certainty by using EEG video monitoring, the time to diagnosis is long, about 7-10 years. This delay indicates that neurologists may have an insufficiently high enough index of suspicion for PNES.

• The patient's history may suggest the diagnosis. Several clues are useful in clinical practice and should raise the suspicion that seizures may be psychogenic rather than epileptic.
• • Resistance to antiepileptic drugs (AEDs) is usually the first clue and the reason for referral to the epilepsy center, though intractable epilepsy is a common cause of resistance to AEDs.
  • Approximately 80% of patients with PNES have been treated with AEDs before the correct diagnosis is made. A psychogenic etiology should be considered when AEDs have no effect on the patient's condition.
  • The presence of specific triggers that are unusual for epilepsy may suggest PNES, and these triggers should be specifically sought during history taking. For example, emotional triggers such as stress or becoming upset are common in PNES. Other triggers that suggest PNES include pain, certain movements, sounds, and seeing of lights, especially if they are reported to consistently trigger an apparent seizure.
  • The circumstances in which attacks occur can be helpful. Like other psychogenic symptoms, those of PNES usually occur in the presence of an audience, and an occurrence in the physician's office or waiting room is highly suggestive of PNES. Similarly, PNES usually do not occur during sleep, though they may seem to and though they may be reported as such.
  • Details of the episodes often include characteristics that are inconsistent with epileptic seizures. In particular, some characteristics of the motor (ie, convulsive) phenomena are associated with PNES (see EEG video monitoring in Other Tests). Common and helpful symptoms include side-to-side shaking of the head, bilateral asynchronous movements (eg, bicycling), weeping, stuttering, and arching of the back.
  • The patient's medical history can be useful. Coexisting, poorly defined, and probably psychogenic conditions, such as fibromyalgia, chronic pain, and chronic fatigue, are associated with psychogenic symptoms (Benbadis, 2005). Similarly, a florid review of systems suggests somatization.
  • A psychosocial history with evidence of maladaptive behaviors or associated psychiatric diagnoses should raise the suspicion of PNES. Pay particular attention during mental status evaluation, especially to the patient's general demeanor, the appropriateness of this or her level of concern, overdramatization, and hysterical features.
• Certain symptoms suggest epileptic seizures. These include significant injury. In particular, tongue biting is highly specific to generalized tonic-clonic seizures and a helpful sign when present.
• Antecedent sexual trauma or abuse is thought to be important in the psychopathology of psychogenic seizures and psychogenic symptoms in general. A history of abuse may be more frequent in convulsive rather than limp type of PNES.

Physical

• Physical and neurologic findings are usually normal.
• Psychological features suggestive of psychogenic episodes include anxiety, depression, inappropriate affect or lack of concern (la belle indifference), multiple and vague somatic complaints suggestive of somatization disorder, and abnormal interaction with family members.

Causes

By definition, PNES is a psychiatric disorder. According to the Diagnostic and Statistical Manual for Mental Disorders (DSM) classification, physical symptoms caused by psychological causes can fall under 3 categories: somatoform disorder, factitious disorder, and malingering.

• A somatoform disorder is the unconscious production of physical symptoms due to psychological factors.
• • The symptoms are not under voluntary control, ie, the patient is not faking and not intentionally trying to deceive.
  • Somatoform disorders are subdivided into several disorders depending on the characteristics of the physical symptoms and their time course.
  • The 2 somatoform disorders relevant to PNES are conversion disorder and somatization disorder.
  • The vast majority of patients with PNES have conversion disorder.
  • The Diagnostic and Statistical Manual for Mental Disorders, Fourth Edition (DSM-IV) added a new subcategory of conversion disorder (from the Diagnostic and Statistical Manual for Mental Disorders, Revised Third Edition [DSM-III-R]) specifically termed conversion disorder with seizures.
• Factitious disorder and malingering imply that the patient is purposely deceiving the physician, ie, faking the symptoms.
• • The difference between factitious disorder and malingering is that, in malingering, the reason for the deception is tangible and rationally understandable (albeit possibly reprehensible). In factitious disorder, the motivation is a pathologic need for the sick role.
  • An important corollary is that malingering is not considered a mental illness, whereas factitious disorder is.
• A generally accepted view is that most patients with PNES have somatoform disorder rather than malingering or factitious disorder.
• • Although the DSM classification is simple in theory, knowing whether a given patient is faking it is nearly impossible. In some circumstances, intentional faking can be diagnosed only by catching a person in the act of faking (eg, self-inflicting injuries, ingesting medications or eye drops to cause signs, putting blood in the urine to simulate hematuria).
  • Malingering may be underdiagnosed, partly because the diagnosis of is essentially an accusation.

DIFFERENTIALS

Section 4 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

Other Problems to be Considered

Epileptic seizures: This is main differential diagnosis. However, proving a nonepileptic origin is not synonymous with proving a psychogenic origin.

Other organic diseases that cause paroxysmal neurological symptoms: These other diseases must be considered in the differential diagnosis. Examples of organic (ie, nonpsychogenic), nonepileptic paroxysmal symptoms are syncope, migraine, cataplexy, and TIAs.

WORKUP

Section 5 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

Lab Studies

• Laboratory studies are useful only in excluding metabolic or toxic causes of seizures (eg, hyponatremia, hypoglycemia, drugs).
• Prolactin and creatine kinase (CK) levels rise after generalized tonic-clonic seizures and not after other types of episodes. However, sensitivity is too low to be of any practical value (ie, lack of elevation does not exclude epileptic seizures).

Imaging Studies

• Although imaging findings are normal in PNES, images should be obtained to exclude organic pathology.
• Incidental abnormalities are occasionally seen on imaging. However, they should not confound the diagnosis if results of EEG video monitoring firmly establish PNES.

Other Tests

• EEG and ambulatory EEG
• • Because of its low sensitivity, routine EEG is not helpful in confirming a diagnosis of PNES. However, repeatedly normal EEG findings, especially in light of frequent attacks and resistance to medications, can be viewed as a red flag.
  • Ambulatory EEG is increasingly used, it is cost effective, and it can contribute to the diagnosis by recording the habitual episode and documenting the absence of EEG changes.
  • However, because of the difficulties in diagnosis (see Treatment), PNES should always be confirmed with EEG video monitoring.
    
• EEG video monitoring
• • EEG video monitoring is the criterion standard for diagnosis and indicated in all patients who have frequent seizures despite taking medications. With an experienced epileptologist, combined electroclinical analysis of both the clinical semiology of the ictus and the ictal EEG findings allows for a definitive diagnosis in nearly all cases. If an episode is recorded, the diagnosis is usually easy, and PNES can usually be differentiated from epilepsy. The principle is to record an episode and demonstrate that no change in the EEG occurs during the clinical event and that the clinical episode is not consistent with seizures unaccompanied by EEG changes. Ictal EEG has limitations because of occasional false-negative results or uninterpretable results if movements generate excessive artifact.
  • Analysis of the ictal semiology (ie, video) is at least as important as ictal EEG because it often shows behaviors that are obviously and unquestionably nonorganic and incompatible with epileptic seizures. Certain characteristics of the motor phenomena are strongly associated with PNES: gradual onset or termination; pseudosleep; and discontinuous (stop-and-go), irregular, or asynchronous (out-of-phase) activity (eg, side-to-side head movement, pelvic thrusting, opisthotonic posturing, stuttering, weeping). A useful sign is preserved awareness during bilateral motor activity; this is relatively specific for PNES because unresponsiveness is almost always present during bilateral motor activity.
• Inductions
• • Provocative techniques, activation procedures, or inductions, can be extremely useful for the diagnosis of PNES, particularly when the diagnosis is uncertain and no spontaneous episodes occur during monitoring.
  • Many epilepsy centers use a provocative technique to aid in the diagnosis of PNES.
  • An intravenous injection of saline is traditionally and most commonly used, but other techniques may be preferable.
  • The principle behind provocative techniques is suggestibility, which is a feature of somatoform disorders in general. For example, in psychogenic movement disorders, for which the diagnosis rests solely on phenomenology (ie, not equivalent to EEG), the response to placebo or suggestion is considered a diagnostic criterion for a definite psychogenic mechanism.
• Short-term outpatient EEG video monitoring with activation
• • When the clinical findings strongly suggest PNES, patients can undergo short-term outpatient EEG video monitoring with activation, as an extension of induction.
  • This study can be cost-effective while retaining the same specificity as other tests and reasonably high sensitivity.
  • In 1 series, 10 of 15 patients had their habitual nonepileptic seizures with hyperventilation plus photic stimulation plus suggestion.
  • At the author's center, this test is routinely used, and the typical episode is observed in 70-80% of patients, obviating long-term EEG video monitoring (Benbadis, 2004).

TREATMENT

Section 6 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

Medical Care

• The patient's understanding of PNES and his or her reactions to the diagnosis affect the outcome; therefore, patient education is crucial.
• • Perhaps the most important step in initiating treatment is delivering the diagnosis to patients and their families.
  • Most patients with psychogenic symptoms have previously received a diagnosis of organic disease (eg, epilepsy); therefore, patients' reactions typically include disbelief and denial, as well as anger and hostility. For example, they may ask "Are you accusing me of faking?" or "Are you saying that I am crazy?"
• Written information can help supplement verbal explanations, but patient information about psychogenic symptoms is scarce.
  • The American Psychiatric Association provides abundant patient education material on diverse topics but not somatoform disorders.
  • Written materials on PNES are scarce but available. Refer to the Bibliography for references.
  • Unless patients and families understand and accept the diagnosis, they will not comply with recommendations. Therefore, communicating the diagnosis is critical.
• The main obstacle to effective treatment is effective delivery of the diagnosis.
  • Physicians are typically uncomfortable with the diagnosis of PNES, and they tend to be uneasy in formulating a conclusion about it. Therefore, physicians' reports are frequently vague and fail to give clear interpretations. They may write, "no EEG change during the episode,no evidence for epilepsy," or "seizures were nonepileptic."
  • Clinicians (eg, referring neurologist, primary physician) may find such reports unhelpful and difficult to explain to patients and families. As a result, patients often continue to be treated for epilepsy, possibly with the understanding that the test results were inconclusive.
  • The diagnosis of PNES should be explained clearly, with unambiguous terms that patients can understand, such as psychological, stress induced, and emotional.
  • The physician delivering the diagnosis must be compassionate, remembering that most patients are not faking, but also firm and confident to avoid the use of wishy-washy and confusing terms. Unfortunately, the indecisive, timid, unclear, or confusing approach is common. Consequently, patients and their families are typically confused, and the problem is perpetuated.
• Psychogenic symptoms are, by definition, a psychiatric disease, and a mental health professional should managed them.
• • Treatment includes psychotherapy and use of adjunctive medications to treat coexisting anxiety or depression.
  • Unfortunately, mental health services are not always easily available, especially for noninsured patients.
  • Another obstacle is that psychiatrists tend to be skeptical about the diagnosis of psychogenic symptoms. Even in PNES, for which EEG video monitoring allows for near-certain diagnosis, psychiatrists tend to disbelieve the diagnosis. A useful approach to combat this skepticism is to provide the treating psychiatrist with video recordings of the findings, can be more convincing than written reports.

Consultations

• From a practical point of view, the role of the neurologists and other medical specialists is to determine whether organic disease exists. Once the symptoms are shown to be psychogenic, the exact psychiatric diagnosis and its treatment are best handled by the psychiatrist.
• Long-term psychotherapy is indicated for patients with PNES, as it is with other manifestations of conversion disorders,
• The neurologist should work with a psychiatrist who understands PNES.
• Nowadays, mental health professionals other than psychiatrists often perform psychotherapy. These professionals include psychologists, social workers, and counselors.
• Psychotropic medications are often needed to treat associated depression and anxiety.

Activity

• Patients with PNES usually do not require any limitation of activities.
• Neurologists vary in their recommendations concerning driving.
• • A preliminary study showed no increased risk of motor vehicle accidents among patients with PNES.
  • Nevertheless, restrictions on potentially hazardous activities (eg, climbing, swimming) may be appropriate in some cases.

FOLLOW-UP

Section 7 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

Further Inpatient Care

• After diagnosis, spend adequate time explaining the diagnosis and its implications to the patient and his or her family.
• Consultation with a psychiatrist need not occur on an inpatient basis.

Further Outpatient Care

• The neurologist should continue to monitor the patient with the psychiatrist or psychologist.

Complications

• Most patients with PNES take anticonvulsants before a correct diagnosis is made.
• A small number also received intravenous medication for status epilepticus that may have resulted in intubation and ICU admissions.

Prognosis

• In general, outcomes in adults are tenuous.
• • After having symptoms for 10 years, more than half of all patients continue to have seizures and remain dependent on social security benefits.
  • Outcomes are improved with education, with an onset and diagnosis at a young age, with episodes characterized by nondramatic features, with few additional somatoform complaints, with low dissociation scores, and with low scores on the high-order personality dimensions (ie, inhibition, emotional dysregulation, compulsivity).
  • Patients with the limp or catatonic type may have a better prognosis than those with the convulsive or thrashing type.
  • PNES severely affects the quality of life of affected patients.
• The duration of illness is probably the most important prognostic factor in PNES; the longer the patient has been treated for epilepsy, the worse the prognosis.
• • Obtaining a definite diagnosis of PNES early in the course of disease is critical.
  • The average delay in the diagnosis of PNES is long, indicating that the index of suspicion for psychogenic symptoms may not be high enough.
  • In addition, an accurate diagnosis of PNES significantly reduces subsequent healthcare costs.
• With PNES, outcomes are generally better in children and adolescents than in adults, probably because the duration of illness is shorter and the psychopathology or stressors are different in pediatric patients than in adults.
• • A refusal to go to school and family discord may be significant factors.
  • Serious mood disorders and ongoing sexual or physical abuse are common in children with PNES and should be investigated in every case.

Patient Education

• Patient education is critical.
• • Thorough patient education is the first step in treatment.
  • Patients and their families must understand the diagnosis to comply with the recommendations of the psychiatric caregiver.
  • Written patient information about PNES is scarce but available. For additional information, visit the Comprehensive Epilepsy Program Web site of the University of South Florida.

MISCELLANEOUS

Section 8 of 9  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

Special Concerns

• PNES in perspective
• • The neurology and epilepsy literature on PNES often implies that PNES is a unique disorder. In reality, PNES is but 1 type of somatoform disorder. How the psychopathology is expressed (PNES, paralysis, diarrhea, or pain) is different only in the diagnostic aspects. Fundamentally, the underlying psychopathology, its prognosis, and its management are no different in PNES than they are in other psychogenic symptoms. Whatever the manifestations, psychogenic symptoms are a challenge in both diagnosis and management.
  • Psychogenic (ie, nonorganic, functional) symptoms are common in medicine. By conservative estimates, at least 10% of all medical services are provided for psychogenic symptoms. These symptoms are also common in neurology, representing approximately 9% of all inpatient neurology admissions and probably an even higher percentage of outpatient visits. Common neurologic symptoms that are found to be psychogenic include paralysis, mutism, visual symptoms, sensory symptoms, movement disorders, gait or balance problems, and pain.
  • For several neurologic symptoms, signs or maneuvers have been described to help differentiate organic from nonorganic symptoms. For example, limb weakness is often evaluated by means of the Hoover test, for which a quantitative version has been proposed. Other examples are looking for give-way weakness and alleged blindness with preserved optokinetic nystagmus. More generally, the neurologic examination is often aimed to elicit symptoms or signs that do not make neuroanatomic sense, eg, facial numbness affecting the angle of the jaw, gait with astasia-abasia or tight-roping.
  • Every medical specialty has its share of symptoms that can be psychogenic. In gastroenterology, these include vomiting, dysphagia, abdominal pain, and diarrhea. In cardiology, chest pain that is noncardiac is traditionally referred to as musculoskeletal chest pain, but it is probably psychogenic. Symptoms that can be psychogenic in other specialties include shortness of breath and cough in pulmonary medicine, psychogenic globus or dysphonia in otolaryngology, excoriations in dermatology, erectile dysfunction in urology, and blindness or convergence spasms in ophthalmology.
  • Pain syndromes for which a psychogenic component is likely include tension headaches, chronic back pain, limb pain, rectal pain, and sexual organ pain. Pain is, by definition, entirely subjective; therefore, to confidently say that pain is psychogenic is essentially impossible, and the term psychogenic is all but discredited in the pain literature. One could even argue that all pains are psychogenic; therefore, psychogenic pain is one of the most uncomfortable diagnoses to make. In addition to isolated symptoms, some consider certain syndromes to be at least partly and possibly entirely psychogenic (ie, without any organic basis). These controversial but fashionable diagnoses include fibromyalgia, fibrositis, myofascial pain, chronic fatigue, irritable bowel syndrome, and multiple chemical sensitivity.
  • For a review of this topic, see the articles by Benbadis (2005) in the Bibliography.
• Uniqueness of PNES among psychogenic symptoms
• • Among psychogenic symptoms, PNES are unique in 1 principal characteristic. With EEG video monitoring, they can be diagnosed with near certainty. This is in sharp contrast to other psychogenic symptoms, which are almost always a diagnosis of exclusion.
  • This unique feature allows a clarity and confidence of diagnosis that may assist in the critical step of convincing the patient and family of the nonorganic nature of the PNES.

REFERENCES

Section 9 of 9

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Follow-up
• Miscellaneous
• References

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Article Last Updated: Sep 28, 2006