Conversion Disorders

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Background

Conversion disorder (Functional Neurological Symptom Disorder) is categorized under the new Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) category of Somatic Symptom and Related Disorders.[1] It involves symptoms or deficits affecting voluntary motor or sensory function that suggest a neurologic or other general medical condition. Yet, following a thorough evaluation, which includes a detailed neurologic examination and appropriate laboratory and radiographic diagnostic tests, no neurologic explanation exists for the symptoms, or the examination findings are inconsistent with the complaint. In other words, symptoms of an organic medical disorder or disturbance in normal neurologic functioning exist that are not referable to an organic medical or neurologic cause.[2]

Common examples of conversion symptoms include blindness, diplopia, paralysis, dystonia, psychogenic nonepileptic seizures (PNES), anesthesia, aphonia, amnesia, dementia, unresponsiveness, swallowing difficulties, motor tics, hallucinations, pseudocyesis and difficulty walking.

Reports of less common manifestations of conversion disorder abound in the literature and include camptocormia, clenched fist syndrome, recumbent gait, odd vocalizations, and pseudo foreign accent syndrome.[3, 4, 5, 6, 7]

Multiple symptoms suggest a somatization disorder. Conversion disorder is a type of somatoform disorder where physical symptoms or signs are present that cannot be explained by a medical condition. Very importantly, unlike factitious disorders and malingering, the symptoms of somatoform disorders are not intentional or under conscious control of the patient. See the image below.



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French neurologist Jean Martin Charcot shows colleagues a female patient with hysteria at La Salpêtrière, a Paris hospital.

Case study

A young woman’s family brings her to the hospital and she presents with a chief complaint of “spells.” It seems that over the past several weeks, the patient has suffered from attacks of bilateral arm jerking, followed by bilateral leg jerking after she lowers herself to the floor. Often, her head shakes violently side to side and her eyes are seen to "roll back in her head" followed by forced eye closure. These incidents follow episodes of emotional outbursts, and the patient is fortunately able to warn others that “I’m about to have a seizure!” After hearing this, her family grabs the patient and places her in a chair or on the ground until the spell is over, which sometimes can wax and wane for 20-30 minutes with varying intensity.

These spells are not accompanied by loss of bladder or bowel continence, but often the patient bites the tip of her tongue and kicks over tables or strikes family members during an episode. This most recent spell occurred while the patient was driving her car, in which she warned of an impending seizure and pulled the car to the shoulder just before losing consciousness; her spell was much more intense than she has had in the past.

She has no significant past medical history and takes no medications. She reports a past history of childhood sexual abuse from a paternal uncle several years ago. On exam, her vitals signs are normal and her neurologic evaluation is without significant findings. She is not orthostatic. Laboratory work-up, including urine toxin screen, is negative.

Pathophysiology

Conversion symptoms suggest a physical disorder but are the result of psychological factors. According to the psychodynamic model, the symptoms are a consequence of emotional conflict, with the repression of conflict into the unconscious. In the late 1880s, Freud and Breuer suggested that hysterical symptoms resulted from the intrusion of "memories connected to psychical trauma" into the somatic innervation. This mind-to-body process was referred to as conversion. Others have introduced attachment theory as a means to understanding conversion disorder in terms of the freeze response and the appeasement defense behavior seen in animal subjects.[8]

The patient has been postulated to derive primary and secondary gain. With primary gain, the symptoms allow the patient to express the conflict that has been suppressed unconsciously. With secondary gain, symptoms allow the patient to avoid unpleasant situations or garner support from friends, family, and the medical system that would otherwise be unobtainable. According to sociocultural theories, the direct expression of emotions is impermissible and somatization takes its place. In behavioral models, conversion symptoms are viewed as a learned maladaptive behavior that is reinforced by the environment.

The idea that conversion disorder does not have an organic basis has become entrenched. However, some evidence supports the opposite notion. A review of imaging correlates in patients with motor and sensory conversion symptoms is referenced.[9, 10] Studies on the natural history of conversion disorder indicate that many patients subsequently develop or are found to have preexisting neurologic disease. In fact, conversion disorders may be more frequently observed in patients with a past history of a central nervous system injury. The simultaneous occurrence of organic brain disease with conversion symptoms is also observed, most notably in observation of high rates of organic seizure syndromes associated with psychogenic nonepileptic seizures (PNES). Familial studies have also shown that conversion symptoms in first-degree female relatives are up to 14 times greater than in the general population.

That the diagnosis of a conversion reaction of disorder represents a failed diagnosis of an organic syndrome, perhaps with psychogenic overlay that obscures exam and other findings is usually a valid concern. A recent meta-analysis including more than 1400 cases with follow-up over 5 years reported missed organic diagnosis rates of less than 5%.[11] This correlates with similar reports for the diagnosis of motor neuron disease or schizophrenia.[12] Past rates of misdiagnosis were reported as considerably higher.[11]

Epidemiology

Frequency

United States

Stefansson et al report that the annual incidence of conversion reactions is 22 cases per 100,000 persons per year in Monroe County, New York. However, the reported rates vary widely.[13] In a study of 100 consecutive women following a normal full-term pregnancy, 33 were noted to have a past history of conversion symptoms. In a study of 100 randomly selected patients from a psychiatry clinic, 24 were noted to have unexplained neurologic symptoms. A report by Carson found that 30% of patients at a neurology clinic had "unexplained symptoms."[14]

Overall, conversion disorder is reported to be more common in rural populations, in individuals with lower socioeconomic status, lack of education, and low psychological sophistication.[15] The increased rate of conversion in patients with a past history of sexual or physical abuse is well described.[16, 17]

International

Stefansson et al report that the annual incidence is 11 cases per 100,000 persons per year in Iceland.[13]

Mortality/Morbidity

Individual conversion symptoms are generally self-limiting and do not lead to physical changes or disabilities. In the case of PNES, patients may have driving privileges removed by medical practitioners and may self-limit other activities due to concern over having a paroxysmal event. The symptoms related to the conversion disorder may lead to decreases in quality of life if they are perceived as egodystonic.

Morbidity is often an iatrogenic manifestation of unnecessary diagnostic or therapeutic interventions aimed at establishing an organic diagnosis for the patient's symptoms.

Patients with chronic conversion symptoms rarely may develop atrophy, frozen joints, and contractures from disuse.

Sex- and age-related demographics

Classically, the female-to-male ratio is 2-10:1.

Recent work with PNES reports that males make up approximately 40% of cases. This is a departure from past work, where females made up 80% of cases of PNES in some series.[18]

Overall, female-to-male ratio is variable, but the occurrence of conversion disorder is likely higher in females overall.

The typical onset is between the second and fourth decades.

The reported range is from children to individuals in their ninth decade of life.

History

Conversion symptoms are those that suggest neurologic disease, but no explanation of these symptoms is found following physical examination and diagnostic testing. The presentation is acute in onset and may follow a psychologically conflictual situation. Conversion symptoms are seen in various clinical settings and include conversion disorder; somatization disorder; affective disorders; antisocial personality disorder; alcohol or drug abuse; or organic, neurologic, or medical illnesses.

In some situations, an immediate precipitating source of stress may be disclosed, such as a loss of employment or divorce. The patient may have a discordant home life. A history of sexual or physical abuse is not uncommon and can be seen in as many as one third to one half of patients with dissociative disorder, respectively. Therefore, a complete and comprehensive psychosocial history is of vital importance. Patients with conversion disorder are said to have a relative lack of concern about the nature or implications of the symptoms; Freud described this as la belle indifference. This is not a helpful diagnostic characteristic because it is not specific or sensitive for conversion and should have no isolated role in separating organic from psychiatric disease.[12] Systematic reviews on this subject found the frequency of this finding at 21% among those with a conversion disorder and 29% among those with organic disease.[19]

Diagnostic criteria (DSM-5)

Diagnostic criteria for conversion disorder as per the DSM-5 are as follows:[1]

Possibilities to consider when a patient presents with symptoms of probable psychogenic origin include the following:

The DSM-5 lists strict criteria for diagnosing conversion disorder. However, 2 of the listed conditions may be determined only by a person with expertise in neurologic conditions, neuroanatomy, and the recognized clinical patterns of disease in correlation with the lesion location. This is usually a neurologist. The psychiatric assessment can differentiate conversion disorder from other somatoform disorders, factitious disorder, and malingering and can elucidate the psychodynamics that are very important in treatment. The neurologist must recognize the nonorganic process and rule out imitators while avoiding potentially dangerous diagnostic or therapeutic interventions. The neurologist and psychiatrist are thus prepared to diagnose conversion disorder best when working in concert.[12]

Patients with conversion disorder may present with hemiparesis, paraparesis, monoparesis, alteration of consciousness, visual loss, seizure like activity, pseudocoma, abnormal gait disturbance, aphonia or dysphonia, lack of coordination, or a bizarre movement disorder. Patients who are more medically naïve typically have more implausible presenting symptoms and vice versa. The presenting symptoms depend on the cultural milieu, the degree of medical sophistication, and the underlying psychiatric issue.

Patients with conversion disorder may deny any emotional problem and quite commonly resist consultation with psychiatry. Therefore, responsibility lies with other medical personnel to perform the initial management prior to conveying the diagnosis.

Physical

A full physical examination with attention to the mental status and neurologic examination should be performed. Certain principles are used during the neurologic examination to distinguish psychogenic deficits from neurologic ones. The pattern of deficits usually does not conform to known anatomic pathways. For example, patients who present with monoparesis do not have weakness in a corticospinal tract or neuropathic or myopathic distribution. In addition, no changes may be seen in reflexes or tone that typically would be expected.

The physician should contrast formal examination from functional observations. Patients who do not move a limb when asked on examination may be observed to use that limb inadvertently while dressing or talking. Importantly, one should differentiate inability to move a limb on command from spontaneous movements. This may imply a receptive aphasia rather than a conversion disorder. Patients who do not dorsiflex the foot while seated may walk on the heels when asked to do so. Another example might be a patient who cannot stand on one leg who may be observed to do so while putting on pants.

Observations when the patient is unaware of being examined are helpful. Patients with psychogenic movements may have no such movements when observed in the waiting room. Multiple examinations by one or more practitioners may disclose variable results. However, caution is necessary when applying these rules. No single feature is absolute. The knowledge pertaining to neuroanatomy and the clinical deficits that arise from certain abnormalities is not completely known, thus resulting in limitations of the neurologic examination. In addition, patients can embellish on organic deficits, thereby making clinical assessment difficult and further introduction of variability between examiners.

Of concern, older data, most notably by Eliot Slater in 1965, published rates of 33% for patients with conversion disorder ultimately developing a physical illness that may account for their symptoms.[20] Patients with conversion disorder not uncommonly have a comorbid medical or neurologic illness. An example is the patient who exhibits both epileptic seizures and psychogenic nonepileptic seizures, a clinical situation accounting for up to 10-20% of referrals to epilepsy referral centers.[21, 22] Although current rates of misdiagnosis are low, this remains a valid concern among practitioners.[11]

Assessment of mental status during examination is paramount. The following mental status examination example focuses only on the possible presentation of a patient with conversion symptoms. In a clinical setting, one would likely see the comorbid psychiatric presentations as well. These may be hard to distinguish and separate from the conversion symptoms (eg, hallucinations and delusions may be a conversion symptom or symptoms of a psychotic disorder).

Mental status examination

See the list below:

Other specific details to help diagnose 3 different common conversion symptoms include the following:

Causes

Neuroimaging studies of conversion disorders indicate hypofunction of the dominant hemisphere and a consequent overactivity in the non-dominant side. Other neuroanatomic findings have been seen with conversion disorder. Marshall et al reported changes in regional cerebral blood flow (rCBF) in a female patient with a left leg paralysis and intact sensory modalities for which no anatomic cause of her weakness could be found. Attempting to move her paralyzed leg did not show activation of contra lateral motor cortex, but rather contra lateral orbit-frontal and anterior cingulated cortex were activated. This implied an anatomic inhibition of primary motor cortex in one case of hysterical paralysis.[29]

Others have shown via rCBF analysis that the left temporal region has decreased rCBF. rCBF studies have also implicated the thalamus, putamen, and caudate on the side opposite the motor and sensory conversion symptoms. Published reports show improved rCBF with resolution of the conversion symptoms.[9]

Functional MRI studies have implicated the orbitofrontal cortex and the anterior cingulate gyrus as active in mediating an inhibitory effect on movement and sensation in patients with psychogenic motor and sensory complaints.[30]

Neuropsychological testing shows evidence of impaired attention and short-term memory.

Psychoanalytic theory postulates that conversion disorder is caused by the repression of unconscious intrapsychic conflicts and conversion of anxiety into physical symptoms.

Learning theorists believe that such symptoms develop from classical conditioning that occurs during childhood and that these learned behaviors arise again as coping mechanisms when the person is subjected to overwhelming stress later in life.

Such symptoms also can be viewed as a form of physical communication of an emotionally charged idea or feeling when one is unable to verbalize the conflict because of personal or social taboos.

Laboratory Studies

Lab tests for hemiparesis include the following:

Lab tests for pseudoseizure (PNES) include the following:

Lab tests for psychogenic movement disorders include the following:

Procedures

The Amytal interview was once commonly used for diagnosing conversion disorder. This procedure carries significant risk and should be carried out by experienced physicians.[31] Sodium Amytal is a barbiturate and carries risk of respiratory depression. It is contraindicated in cases of upper respiratory infection or airway edema, hemodynamic instability, significant liver or kidney dysfunction, and porphyria. A CPR cart with medications and personnel trained in their use should be available in case of emergency.[32] This is cited in the literature as a technique that may occasionally be used to help facilitate the gathering of data but is not routinely performed in many centers.

Hypnosis is used on occasion and may also facilitate the data gathering process. This technique may also help alleviate the patient's anxiety and aid in relaxation.

Brain PET scan has demonstrated evidence of left dorsolateral prefrontal cortex hypofunction.

SPECT scan has shown decrease in regional blood flow in the thalamus and basal ganglia contralateral to the deficit.

Advanced imaging is not diagnostic of conversion disorder, and routine use for this purpose is not currently standard of care.

See Causes for rCBF studies.[9]

Medical Care

Current understanding of the phenomenon of conversion disorder implicates some role of the unconscious in the pathophysiology of this condition.[12, 33] It is therefore less likely to respond to treatment when the manifestations of the conversion are confronted directly as a unitary method of therapy. Many patients who experience a conversion disorder are unable to understand this inner conflict, which is perhaps occurring on an unconscious level. They may achieve resolution of the conflict, as well as their physical symptoms, once they are gently made aware of this connection. Once the patient is aware of this, the psychologic currency of the symptom loses value, and the symptom may be allowed to improve.

Hospital admission may be considered in some cases. For example, for a patient that seems likely to not return for follow-up after being given a psychiatric diagnosis. A more rapid completion of the diagnostic workup is possible in the hospital setting. In addition, a parallel investigation of physical and psychologic factors can concomitantly be pursued. One caveat to note is that the clinical situation may be worsened by providing the patient with the secondary gain he or she is seeking.

Avoid invasive diagnostic and therapeutic interventions.

Tactful presentation of the diagnosis to the patient includes the following:

No specific pharmacologic therapy is available for conversion disorder; however, medications for comorbid mood and anxiety disorders should be considered. Care should be taken to avoid dependence-producing psychotropic agents.

Physical therapy may be warranted and is often helpful in providing the patient an ego-syntonic way out as they are being provided a benign treatment to which they can respond and improve.[34, 35]

Institute patient and family education sensitively.

Regular short follow-up appointments with a neurologist or a psychiatrist should be provided to limit ED visits and unnecessary diagnostic or invasive tests.

Consultations

A multidisciplinary approach to the treatment of conversion disorder is beneficial.[33]

Medication Summary

Sparse evidence exists for use of medications for the independent treatment of conversion. Medications that have been tried with success include tricyclic antidepressants, haloperidol, and also treatment with electroconvulsive therapy (ECT).[36, 37] Treatment of coexisting psychological or psychiatric disease is warranted.

Prognosis

Approximately 75% of patients will experience spontaneous resolution. Approximately 25% of patients will experience recurrence of the same or different conversion symptoms at 15-year follow-up.

Patient Education

Sensitively review the disorder with the patient and the family in such a way as to not place blame. During such follow-up for review of completed imaging and other studies, continue to emphasize the importance of pain or other symptoms that the patient may be having.

Continue to reassure the patient that the negative test results are good news and bode well for their eventual recovery.

Frequent brief office visits to ensure the expected resolution of their symptoms may be helpful.

Websites that may provide further information and support for patient and family education include the following:

Author

Scott A Marshall, MD, Major, Medical Corps, US Army; Assistant Professor of Neurology, Uniformed Services University of the Health Sciences; Staff Neurologist, Staff Intensivist, Brooke Army Medical Center

Disclosure: Nothing to disclose.

Coauthor(s)

Alexis Llewellyn, PhD, Licensed Psychologist and Owner, Katy Center for Psychology and Counseling Services

Disclosure: Nothing to disclose.

Bryan Schwieters, MD, Consulting Physician, Schwieters Medical PLLC and VirtualPsych, LLC

Disclosure: Received consulting fee from pfizer for speaking and teaching.

Craig G Carroll, DO, Staff Neurologist, Head of Clinical Neurophysiology Section, Naval Medical Center Portsmouth

Disclosure: Nothing to disclose.

Mark E Landau, MD, Associate Professor of Neurology, Uniformed Services University of the Health Sciences; Consulting Staff, Assistant Chief, Section of Neurophysiology, Department of Neurology, Walter Reed Army Medical Center

Disclosure: Nothing to disclose.

Specialty Editors

Francisco Talavera, PharmD, PhD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Chief Editor

David Bienenfeld, MD, Professor, Departments of Psychiatry and Geriatric Medicine, Wright State University, Boonshoft School of Medicine

Disclosure: Nothing to disclose.

Additional Contributors

Barry I Liskow, MD, Professor of Psychiatry, Vice Chairman, Psychiatry Department, Director, Psychiatric Outpatient Clinic, The University of Kansas Medical Center

Disclosure: Nothing to disclose.

Acknowledgements

The opinions expressed in this work belong solely to those of the authors. They should not be interpreted as necessarily representative or endorsed by the Uniformed Services University, The United States Army, The Department of Defense, or any other agency of the federal government.

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French neurologist Jean Martin Charcot shows colleagues a female patient with hysteria at La Salpêtrière, a Paris hospital.

French neurologist Jean Martin Charcot shows colleagues a female patient with hysteria at La Salpêtrière, a Paris hospital.