Overview
Conversion disorder is a psychiatric condition in which symptoms and deficits in voluntary motor and/or sensory function (such as blindness, paralysis) suggest a neurologic or physical condition but are without organic or physiologic explanation. In simpler terms, conversion disorders are physical symptoms which are caused subconsciously by psychologic stress. Conversion disorder as defined in DSM-IV describes symptoms such as weakness, seizures, or abnormal movements that are not attributable to a general medical condition or to feigning and that are judged to be associated with psychological factors. La belle indifférence refers to an apparent lack of concern shown by some patients towards their symptoms. It is often regarded as typical of conversion symptoms/hysteria.
Conversion disorder is also called functional neurological symptom disorder, referring to abnormal central nervous system functioning. A key feature of conversion disorder is the incompatibility between an individual’s symptoms and recognized neurological or medical conditions.
Related Disorders
Symptoms of the following disorders can be similar to those of conversion disorder. Comparisons may be useful for a differential diagnosis:
Somatoform disorders (also called Briquet syndrome) are marked by persistent physical symptoms that cannot be fully explained by a medical condition, substance abuse, or other mental disorder, and seem to stem from psychological issues or conflicts.
Somatization Disorder is a psychological disorder characterized by frequent and numerous physical complaints that are not due to any physical disorder. The disorder begins before the age of 30 and complaints are usually vague, dramatic and exaggerated. The patient is usually found to be under the care of several physicians simultaneously.
Hypochondria is a psychological disorder in which there is a preoccupation with having a serious disease without any physical disorder. This fear continues despite medical reassurance that there is no physical problem.
Neurological disorders that can cause similar waxing and waning symptoms, but have a physiological basis include multiple sclerosis, Tourette syndrome, Wilson’s disease, demylinating polyneuropathy, and many, many more disorders affecting the central nervous system.
Symptoms
The most common symptoms of conversion disorder are similar to those associated with neurological disease. These include
- paralysis (usually in an arm or leg)
- loss of voice (aphonia)
- disturbances in coordination (apraxia)
- impaired or jerky movements
- temporary blindness
- tunnel vision
- loss of the sense of smell (anosmia) or touch (anesthesia)
- a tingling sensation to the skin (paranesthesia)
- loss of ability to understand or express speech (aphasia)
Pseudoparalysis. In pseudoparalysis, the patient loses the use of half of his/her body or of a single limb. The weakness does not follow anatomical patterns and is often inconsistent upon repeat examination.
Pseudosensory syndromes. Patients with these syndromes often complain of numbness or lack of sensation in various parts of their bodies. The loss of sensation typically follows the patient’s notion of their anatomy, rather than known characteristics of the human nervous system.
Pseudoseizures. These are the most difficult symptoms of conversion disorder to distinguish from their organic equivalents. Between 5% and 35% of patients with pseudoseizures also have epilepsy. Electroencephalograms (EEGs) or measurement of serum prolactin levels, are useful in distinguishing pseudoseizures from epileptic seizures.
Pseudocoma. Pseudocoma is also difficult to diagnose. Because true coma may indicate a life-threatening condition, patients must be given standard treatments for coma until the diagnosis can be established.
Psychogenic movement disorders . These can mimic myoclonus, parkinsonism, dystonia, dyskinesia, and tremor. Doctors sometimes give patients with suspected psychogenic movement disorders a placebo medication to determine whether the movements are psychogenic or the result of an organic disorder.
Pseudoblindness. Pseudoblindness is one of the most common forms of conversion disorder related to vision. Placing a mirror in front of the patient and tilting it from side to side can often be used to determine pseudoblindness, because humans tend to follow the reflection of their eyes.
Pseudodiplopia. Pseudodiplopia, or seeing double, can usually be diagnosed by examining the patient’s eyes.
Pseudoptosis. Ptosis, or drooping of the upper eyelid, is a common symptom of myasthenia gravis and a few other disorders. Some people can cause their eyelids to droop voluntarily with practice. The diagnosis can be made on the basis of the eyebrow; in true ptosis, the eyebrows are lifted, whereas in pseudoptosis they are lowered.
Hysterical aphonia. Aphonia refers to loss of the ability to produce sounds. In hysterical aphonia, the patient’s cough and whisper are normal, and examination of the throat reveals normal movement of the vocal cords.
Causes
Conversion disorder is thought to be caused by an “internal” conflict that creates extreme psychological stress. Conversion symptoms represent a partial solution to a conflict. Patients with conversion disorder reported a higher incidence of physical/sexual abuse, a larger number of different types of physical abuse, sexual abuse of longer duration, and incestuous experiences more often than comparison patients.
In a study of 34 children who developed pseudoseizures, 32% had a history of depression or sexual abuse, and 44% had recently experienced a parental divorce, death, or violent quarrel. In the adult population, conversion disorder may be associated with mobbing, a term that originated among European psychiatrists and industrial psychologists to describe psychological abuse in the workplace.
Two terms that are used in connection with the causes of conversion disorder are primary gain and secondary gain. Primary gain refers to the lessening of the anxiety and communication of the unconscious wish that the patient derives from the symptom(s). Secondary gain refers to the interference with daily tasks, removal from the uncomfortable situation, or increased attention from significant others that the patient obtains as a result of the symptom(s).
Functional brain imaging studies showing findings such as contralateral thalamic hypoactivity in hemisensory conversion encourage us to understand conversion symptoms from a brain as well as mind perspective.
Diagnosis
Functional leg weakness can be demonstrated objectively when weakness of hip extension disappears during contralateral hip flexion against resistance (Hoover’s sign). Functional arm tremor is suspected when a tremor disappears during voluntary rhythmical movement of the unaffected arm. The current DSM-V criteria require the positive exclusion of feigning. Proving feigning is difficult
enough; proving the absence of feigning is arguably impossible.
It is important for the doctor to rule out serious medical disorders in patients who appear to have conversion symptoms. The following disorders must be considered in the differential diagnosis:
- multiple sclerosis (blindness resulting from optic neuritis)
- myasthenia gravis (muscle weakness)
- periodic paralysis (muscle weakness)
- myopathies (muscle weakness)
- polymyositis (muscle weakness)
- Guillain-Barré syndrome (motor and sensory symptoms)
Comorbidity
At least one psychiatric diagnosis was found in 89.5% of the patients during the follow-up evaluation. Undifferentiated somatoform disorder, generalized anxiety disorder, dysthymic disorder, simple phobia, obsessive-compulsive disorder, major depression, and dissociative disorder not otherwise specified were the most prevalent psychiatric disorders. A dissociative disorder was seen in 47.4% of the patients. These patients had dysthymic disorder, major depression, somatization disorder, and borderline personality disorder more frequently than the remaining subjects. They also reported childhood emotional and sexual abuse, physical neglect, self-mutilative behavior, and suicide attempts more frequently.
Pharmacological Treatment
The research lacks but their is a successful case of treating a patient with conversion disorder with Valproate ER. Opipramol (200 mg/day) has found to be very effective in treating patients with somatoform disorder. The effect of antidepressant in treating conversion disorders are still in debate, where the longitudinal studies are missing, however venlafaxine, imipramine, fluvoxamine, fluoxetine, citalopram, levetiracetam and naloxene have shown some positive response in treating pateints with conversion disroder.
The non pharmacological treatment includes deep hypnosis and cognitive behavioral therapy.
