Functional weakness and sensory disturbance

In the diagnosis of functional weakness and sensory disturbance, positive physical signs are as important as absence of signs of disease. Motor signs, particularly Hoover's sign, are more reliable than sensory signs, but none should be used in isolation and must be interpreted in the overall context of the presentation. It should be borne in mind that a patient may have both a functional and an organic disorder.

Motor initiation and execution in patients with conversion paralysis

Motor initiation and motor execution in four patients with conversion paralysis were investigated in a non-affected motor modality (speech). In line with the hypothesis of dissociated control in conversion disorder [Cognit. Neuropsychiatry 8 (1) (2001) 21] motor initiation, but not response duration, was expected to be impaired. The motor initiation times (reaction time: RT) and motor execution times (response duration: RD) were compared on four RT-tasks that required the production of a verbal response: a simple choice RT-task, a mental letter rotation task, and an implicit and an explicit mental hand rotation task. Because conversion disorder is expected to primarily involve an impairment in the initiation of movement, we expected the following task characteristics to uniquely affect RT and not RD: type of instruction (implicit versus explicit instructed imagery), angle of rotation, and target arm (affected versus non-affected arm). The results indeed showed the task characteristics to significantly affect the participants' RT and not their RD. It was concluded that conversion paralysis is associated with a specific impairment in the explicit initiation of processes with a spatial and motor component.

Psychogenic sensory loss: magnetic source imaging reveals normal tactile evoked activity of the human primary and secondary somatosensory cortex

We investigated the activation of the secondary somatosensory cortex (SII) in three patients with unilateral psychogenic sensory loss in the hand. Somatosensory evoked magnetic fields were recorded in response to tactile stimulation of the index finger of the affected and the unaffected hand. Brain sources were estimated by magnetic source imaging. In all subjects, responses in both the contralateral primary somatosensory (SI) and bilateral SII areas were normal as compared with a healthy control group, irrespective of the stimulated side. The results extend previous findings of normal evoked activity in SI.

Conversion disorder in children and adolescents: a 4-year follow-up study

OBJECTIVE

To assess the outcome of conversion disorder in children and adolescents and to identify factors affecting the prognosis.

METHOD

Forty adolescents with conversion disorder were reevaluated 4 years after their initial interview. Changes in demographic and clinical data and the presence of any mood and anxiety disorders were recorded using the Structured Clinical Interview for DSM-IV Axis I Disorder (SCID-I). In addition, Beck Depression Inventory (BDI) and State-Trait Anxiety Inventory (STAI) were applied.

RESULTS

Thirty-four patients (85%) had completely recovered from their conversion symptoms and two patients had improved (5%), whereas only four (10%) were unchanged. Fourteen (35%) patients received the diagnosis of mood and/or anxiety disorder. Favourable outcome was associated with early diagnosis (P=.04) and good premorbid adjustment (P=.01).

CONCLUSION

Conversion disorder has a favourable outcome in children and adolescents. However, mood and/or anxiety disorders are encountered at a considerable rate in these patients even after recovery from conversion symptoms. Long clinical follow-up seems appropriate in children and adolescents with conversion disorder.

Conversion sensory symptoms associated with parietal lobe infarct: case report, diagnostic issues and brain mechanisms

This case report suggests that diagnostic difficulties and brain mechanisms related to conversion disorder associated with cerebral lesions differ from those related to conversion disorder without cerebral lesions. A 35-year-old divorced woman was admitted to a psychiatric inpatient unit with multiple physical complaints. The symptoms first appeared 5 years previous and 2 months after a sexual assault. Three years later, she began to experience ill-defined sensory symptoms confined to the left half of her body (splitting the midline). Results of neurologic consultations were equivocal because of the subjective nature of the complaints, which were viewed as conversion symptoms. A magnetic resonance imaging scan demonstrated an old infarct in the right parietal lobe, suggesting a physical origin of the patient's symptoms. However, normal somatosensory-evoked responses from the affected area contributed little to establishing the diagnosis. The results of all further investigations to identify causes of the vascular pathology were negative. The multiple ill-defined somatic symptoms, the distribution of sensory symptoms and the resolution of symptoms with psychotherapy established the diagnosis of conversion disorder superimposed on a pre-existing right parietal lesion. This case highlights the importance of clinical features in establishing a diagnosis such as this. We suggest that reactivation of implicit sensory memories (represented at the thalamic level and resulting from decreased corticofugal inhibitions due to the lesion) may contribute to the formation of sensory conversion symptoms in individuals with parietal lobe lesions.

Functional neuroanatomical correlates of hysterical sensorimotor loss

Hysterical conversion disorders refer to functional neurological deficits such as paralysis, anaesthesia or blindness not caused by organic damage but associated with emotional "psychogenic" disturbances. Symptoms are not intentionally feigned by the patients whose handicap often outweighs possible short-term gains. Neural concomitants of their altered experience of sensation and volition are still not known. We assessed brain functional activation in seven patients with unilateral hysterical sensorimotor loss during passive vibratory stimulation of both hands, when their deficit was present and 2-4 months later when they had recovered. Single photon emission computerized tomography using (99m)Tc-ECD revealed a consistent decrease of regional cerebral blood flow in the thalamus and basal ganglia contralateral to the deficit. Independent parametric mapping and principal component statistical analyses converged to show that such subcortical asymmetries were present in each subject. Importantly, contralateral basal ganglia and thalamic hypoactivation resolved after recovery. Furthermore, lower activation in contralateral caudate during hysterical conversion symptoms predicted poor recovery at follow-up. These results suggest that hysterical conversion deficits may entail a functional disorder in striatothalamocortical circuits controlling sensorimotor function and voluntary motor behaviour. Basal ganglia, especially the caudate nucleus, might be particularly well situated to modulate motor processes based on emotional and situational cues from the limbic system. Remarkably, the same subcortical premotor circuits are also involved in unilateral motor neglect after organic neurological damage, where voluntary limb use may fail despite a lack of true paralysis and intact primary sensorimotor pathways. These findings provide novel constraints for a modern psychobiological theory of hysteria.

Paraplegia diagnosed by a new physical sign

Clinical diagnosis is a process of logical deduction from the data gathered by history and physical examination. When organic causes of an illness have been ruled out, a diagnosis of "functional disorder" or "conversion reaction" is considered. Cost of care of such patients can be enormous, especially when a large number of investigations are done to find an organic illness, which does not really exist. In such cases, a positive and early diagnosis of a conversion reaction can save needless tests and much distress to the patient. This report describes a case of paraplegia that was investigated for years before a diagnosis of conversion reaction was firmly made, based on a novel observation. We believe that we describe here a new physical sign, which can be used to diagnose "hysterical paraplegia."

Persistent or severe back pain and stiffness are ominous symptoms requiring prompt attention

BACKGROUND

Children with severe or persistent back pain and stiffness often have an underlying organic cause but there is a large differential diagnosis, examination may be difficult and the problem is relatively rare in general paediatric practice. These difficulties appeared to lead to delays in diagnosis and management of children with this problem.

OBJECTIVES

To provide an approach to the diagnosis and management children with severe or persistent back pain or stiffness based on our clinical experience and the literature.

METHODOLOGY

The case histories of 10 children with severe back pain seen by the authors over a 5-year period were reviewed. They were chosen as illustrative examples of the diagnostic and management problems and did not represent a systematic review of all cases seen by the authors over that time.

RESULTS

Underlying causes included infection, inflammation, neoplasm, trauma and vascular malformation. Four of the children had spinal cord compression which required urgent decompression. There was one child with a conversion disorder but three children with organic disease were initially felt to have a conversion disorder. Investigations generally proceeded relatively slowly and the problem was not regarded as a semi-urgent situation carrying the risk of permanent paraplegia. Magnetic resonance imaging (MRI) scan of the spine was the investigation of choice.

CONCLUSION

Children with severe or persistent back pain and stiffness have a wide variety of underlying causes. The possibility of underlying spinal cord compression should always be considered in children with this presentation. If the diagnosis is not obvious, MRI scan of the spine should be arranged without delay.

Imaging hypnotic paralysis: implications for conversion hysteria

In a single case study with positron emission tomography (PET) functional imaging, hypnotic paralysis activated similar brain areas to those in conversion hysteria, supporting the view that hypnosis and hysteria might share common neurophysiological mechanisms.

Differentiation of conversive sensory loss and malingering by P300 in a modified oddball task

We applied the methodology of evoked potentials (EP) to reveal the functional level of abnormality in a patient with circumscribed complete anaesthesia due to conversion disorder. EP components related to sensory and perceptual processing of both innocuous electrical and noxious laser stimuli were normal. However, a P300 component indicating cognitive processing failed to appear when using a modified oddball task with rare stimuli applied to the anaesthetic right hand. P300 was present with this paradigm stimulating the healthy left hand, as well as in a 'malingerer' - a healthy subject who was instructed to feign the same deficit. These results suggest cognitive deficits underlying sensory loss as conversion symptom which can be differentiated from malingering by use of P300.

Conversion disorders in Nottingham: alive, but not kicking

A postal request to general practitioners in a catchment area (population 37,000) identified 18 patients fulfilling criteria for conversion disorder (age range 26-74 years; mean age of onset of first episode 38 years). There was a female preponderance, with two patients from ethnic minority groups. There was a temporal correlation with stress in 13 cases (72%) and a history of sexual abuse in 5 cases (28%). Three clinical groups were identified: acute onset with good premorbid functioning and full recovery; conversion symptoms as part of polysymptomatic presentation, with fluctuating course; and chronic, severely disturbed individuals with a past history of sexual abuse. One third of cases were referred to psychiatrists. There was no case of a missed organic disorder. The details of one case are discussed.

The functional anatomy of a hysterical paralysis

The concept of a conversion disorder (such as hysterical paralysis) has always been controversial (Ron, M.A. (1996). Somatization and conversion disorders. In: B.S. Fogel, R.B. Schiffer & S.M. Rao (Eds.), Neuropsychiatry. Williams and Wilkins, Baltimore, MD). Although the diagnosis is recognised by current psychiatric taxonomies, many physicians still regard such disorders either as feigned or as failure to find the responsible organic cause for the patient's symptoms. We report a woman with left sided paralysis (and without somatosensory loss) in whom no organic disease or structural lesion could be found. By contrast, psychological trauma was associated with the onset and recurrent exacerbation of her hemiparalysis. We recorded brain activity when the patient prepared to move and tried to move her paralysed (left) leg and when she prepared to move and did move her good (right) leg. Preparing to move or moving her good leg, and also preparing to move her paralysed leg, activated motor and/or premotor areas previously described with movement preparation and execution. The attempt to move the paralysed leg failed to activate right primary motor cortex. Instead, the right orbito-frontal and right anterior cingulate cortex were significantly activated. We suggest that these two areas inhibit prefrontal (willed) effects on the right primary motor cortex when the patient tries to move her left leg.

Conversion disorders in adolescents: a practical approach to rehabilitation

Young people with conversion disorders require a different treatment approach compared with those who have organic illness. This paper describes a team approach which is based on detailed assessment, explanation of the vicious cycle, accepting the patient's symptoms, working towards achievable goals, encouraging bravery, rewarding 'wellness' behaviour, ignoring abnormal behaviour and supervising re-integration into school.

A study of 111 cases of globus hystericus

Videofluorography (VFG) and manometry were used to evaluate 111 patients who were diagnosed with globus hystericus. Most of the globus patients were affected by functional diseases and the underlying pathology could be revealed by VFG in 73.9 per cent of the series and by manometry in 80.2 per cent. There were 10.8 per cent of the series in which VFG and manometry yieled normal findings. The most common abnormality determined by manometry was esophageal aperistalsis. The most common abnormality revealed by VFG was cricopharyngeal bar. VFG was sensitive for morphologic detection while manometry was sensitive for motility study. Functional disorders can result in morphologic abnormality and vice versa. Therefore, VFG and manometry complement each other and are invaluable tools in the investigation of globus patients.

Camptocormia: a biomechanical analysis. A case report

Although camptocormia, a conversion disorder associated with the disability of severely forward-bent posture, has been reported in the literature, to date there has been no report of a detailed kinematic or biomechanical analysis of this disability. Presented is a 47-yr-old male engineer with severely forward-bent posture during walking. One year ago, after playing tennis, he developed low back pain followed by a sensation that to walk comfortably he had to assume a forward-bent posture. Two months later, although the low back pain had resolved, he maintained the same unusual walking pattern. Although he could walk a few steps in the upright position, he would spontaneously revert to the forward-bent posture. Physical examination was normal except for bilateral 10 degree hip flexion contractures. Gait laboratory analysis, including kinematics, kinetics, and dynamic electromyography, revealed exaggerated anterior pelvic tilt during terminal stance when he walked in an upright posture. In the forward-bent posture, however, this anterior pelvic tilt was significantly less. It is possible that his unusual forward-bent posture was a compensatory mechanism to reduce excessive pelvic tilt. Although this rare disability has been previously attributed to a conversion disorder, there may be, in some instances, a biomechanical component.

[Conversion hysteria]

Conversion disorder is characterized by symptoms or deficits affecting voluntary motor or sensory function that suggest a neurological condition. The symptoms or deficits are related to psychological factors but not intentionally produced or feigned. They could be associated with true neurological disorders and their diagnosis is difficult. Neurologically they do not conform to known neurological mechanisms but instead follow the individual conceptualization of a condition and vary according to attention and emotions. Psychologically they are related to a psychic conflict or a stressful event. They could be associated to other manifestations of the hysterical neurosis or various mental conditions.

Outcome in conversion disorder: a follow up study

Fifty six patients who had been admitted with a conversion disorder other than pseudoseizures were interviewed; mostly by telephone. The median interval was 4.5 years. If a patient had improved during a stay in hospital the eventual outcome was good in 96%, against only 30% in the others (risk ratio 3.2 (95% CI 1.8-5.6)). Rapid improvement was, in turn, related to recent onset of the symptoms. Two patients (4%) subsequently developed an organic deficit that, in retrospect, might be related to the initial episode.

Emergency department presentation of patients with conversion disorder

OBJECTIVE

To describe the presenting symptoms and other features of ED patients diagnosed as having conversion disorder.

METHODS

A retrospective chart review was carried out on the records of ED patients who had had final ED or in-hospital diagnoses of conversion disorder. Cases from 1982 to 1992 at a 566-bed rural tertiary care hospital with a residency program in emergency medicine were reviewed for patient age and gender, presenting signs and symptoms, ED diagnostic evaluation, disposition, and comorbidity.

RESULTS

Of 42 patients who had conversion disorder diagnoses, 24 were women and 18 were men. Twenty-one (50%) of the patients were diagnosed in the ED, and of those patients, ten were released home from the ED. Patient age ranged from 5 to 70 years, with a mean age of 33 years for women and 34 years for men. Most clinical symptoms mimicked neurologic disorder (weakness, pain, seizure-like activity, loss of consciousness, etc). Thirty patients (71%) received laboratory studies in the ED and two others received laboratory studies on admission. Seventeen (40%) patients had computed tomography of the head and five (12%) patients had magnetic resonance imaging of the head. Twelve (29%) patients had previous histories of psychiatric disorders, four (10%) had histories of alcohol and drug abuse, two (5%) had prior conversion reactions, three (7%) had chronic illnesses, and four (10%) had been victims of previous head trauma.

CONCLUSION

Patients with conversion disorder in the ED usually present with neurologic symptoms and undergo multiple diagnostic tests. Comorbidity is common. Early psychiatric evaluation may assist in the diagnosis and evaluation of patients with suspected conversion disorder in the ED.

Psychogenic seizures in children: long-term analysis of 43 cases

Forty-three patients exhibiting psychogenic seizures with onset before the age of 16 years were studied. All patients underwent intensive electroencephalography and video-electroencephalography monitoring. Thirty-two were female and 11 male. Mean age of the population at seizure onset was 12.4 years (range, 5 to 16 years). Twenty-one patients (48.8%) were taking anticonvulsants. Neurologic past history was abnormal in nine cases. Family history of epilepsy was found in 15 cases (34.9%). Median seizure frequency was one seizure every 5 days. Clinical characteristics of the seizures varied. However, unresponsiveness with generalized violent and uncoordinated movements involving the whole body (n = 19) or with generalized trembling (n = 11) were the most common features. Neuropsychological testing, carried out in 22 cases, failed to show major abnormalities in most of the cases. Significant personal and family distress was found in most of the cases. An important impact on patient's quality of life was evident when the seizures were present as compared to the seizure-free periods. There were no statistically significant predictors of clinical outcome.

Conversion disorder revisited: severe parasomnia discovered

In light of recently described and reviewed disorders of movement and behaviour during sleep, the long standing diagnosis of conversion disorder in a forty-nine year old Vietnam veteran was reappraised. Polysomnographic studies showed that the nocturnal component of his "pseudoseizures" was due to physical disorder, a severe mixed parasomnia comprising the recently described REM behaviour disorder and a non-REM parasomnia. His sleep architecture was also deranged, featuring reduced REM latency and increased REM density. An association between these abnormalities and psychological trauma is recognised in the literature. Treatment with clonazepam has abolished the nocturnal behavioural disturbance. His daytime pseudoseizures occur less frequently and his general well being is improved. The case is a reminder that physical disorder may underlie and act as prototype to the psychologically-driven symptom. Before attributing behavioural disturbance at night to psychological causes alone, polysomnographic studies should be done to exclude a treatable parasomnia.