Despite diversified clinical and technical assessment, medically unexplained symptoms still account for a major subgroup of neurologic inpatients and outpatients (1). Pseudoneurologic symptoms may be viewed from various clinical and theoretic perspectives (2). A major psychiatric approach to put an order to this indeed heterogeneous class of symptoms is to differentiate between voluntary and involuntary symptom production, indicating conscious versus unconscious motivation. Malingering (i.e., intentionally feigning or producing somatic symptoms in order to obtain primary external gains) is the simple type of abnormal illness behavior. Purposeful deception is also an integral part of factitious disorder. As a rule, factitious disorder does not only comprise complex psychopathologic and psychodynamic factors, but also cannot be explained by obvious external influences. Self-harm, very often assuming alarming proportions, can sometimes result in life-threatening somatic conditions that seem to be in no reasonable relation to any secondary advantage. Münchausen syndrome may be considered as an extreme variant of chronic factitious disorder. Apart from patients falsely reporting symptoms or feigning states of illnesses by deliberately inducing self-harm to the body and thus deceiving doctors, Münchausen syndrome also includes pseudologia phantastica, itinerant behavior, and signs of social disintegration. On the other hand, there is a wide range of the so-called somatoform disorders, which are characterized by bodily symptoms that suggest a physical disorder but for which there are no demonstrable organic causes or known pathophysiologic mechanisms. These symptoms are, with high probability, linked to psychological factors, conflicts, or psychosocial stressors. Conversion disorder is the classic prototype of somatoform disorders. It involves a loss or change in sensory or motor functions, or in the regulation of consciousness accompanied by nonepileptic seizures. Conversion symptoms may also be part of somatization disorder, not only characterized by pseudoneurologic symptoms, but also by many functional disorders or pains in other organ systems. In contrast to malingering and factitious disorder, symptom production in somatoform disorder must be involuntary by definition. Official psychiatric classification systems such as the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), and the International Classification of Diseases (ICD-10) follow these categoric differentiations between somatoform disorders on the one hand, and factitious disorders and malingering on the other. This division into categoric diagnostic subgroups, however, causes many problems in clinical practice, so it sometimes seems to be very elusive to demonstrate unconscious motivation in cases of conversion disorder and not to stress a prevailing socially manipulative motive or to recognize an obvious secondary gain. And even if patients with factitious disorders are aware of the fact that they are deceiving their doctors by feigning a somatic condition, they may be totally unaware of the compulsory nature of self-harm which they may induce in a dissociative state. In addition, during individual courses of illness, there may be transitions from a somatoform disorder to a factitious disorder and vice versa (3, 4, 5). From a pragmatic standpoint of consultation/liaison (C/L) psychiatric activities, therefore, it is preferred to study all these pseudoneurologic conditions within one framework of analysis.

In an initial categoric approach, we applied the diagnostic logic of DSM-III-R to patients with conversion syndromes referred to C/L service for psychiatric evaluation after a complete neurologic assessment had ruled out explaining neurologic disorders. In a prospective study lasting four years, 169 patients with pseudoneurologic signs of conversion were included (6). There was a typical majority of women (n = 121). From a clinical phenomenologic point of view, the following conversion syndromes were presented:

According to the diagnostic criteria of DSM III-R, three subgroups were differentiated: conversion disorder (n = 132), somatization disorder (n = 28), and factitious disorder (n = 9) (factitious disorder was diagnosed only if it was fortuitously discovered while a patient was engaged in factitious illness behavior, paraphernalia such as syringes or medications were detected among the patient’s belongings, or laboratory tests suggested a factitious etiology). It must be stressed that clinical phenomenology of pseudoneurologic symptoms showed no differences among the three subgroups defined by psychiatric diagnostic categories.

A typical psychosocial stressor or intrapsychic conflict could be a decisive eliciting situation for the great majority of patients with conversion disorder. There were many types of conflicts, but any specificity of conflict could not be established regarding the special pseudoneurologic symptom produced in the process of conversion. The longer a conversion symptom persisted, the more important the secondary gains in the patients’ social environment seemed to be. Outstanding, long-lasting psychosocial burdens and unsolvable chronic conflicts characterized the subgroup with somatization disorder. Conversion symptoms in this
subgroup were in line with many other functional disorders and remarkable social disabilities. They were part of a highly complex abnormal illness behavior. Acute stressors or obvious secondary gains could not be detected in the small subgroup of patients with factitious disorder. Their sometimes serious self-induced injuries and covert dangerous self-harm rituals, in addition to a prominent conversion symptom, meant a dreadful contrast to what would be, at first glance, an otherwise unspectacular-looking superficial adaptation. Intermittent and acute courses of illness were prevailing in conversion disorder, whereas chronic courses predominated in the other two subgroups.

Considering the dimension of comorbidity, the splitting into the three diagnostic subgroups of patients with conversion symptoms was important. High rates of psychiatric comorbidity such as substance abuse, major depression, anxiety disorders, and so on were typical of patients with somatization disorder. Increasing frequency of additional axis II diagnoses (i.e., personality disorders) were obvious in the two subgroups of patients with somatization and factitious disorder, thus underlining the more complex determination of symptom production in both groups (Table 19.1).

Frequent autodestructive aspects (suicidality, deliberate and covert self-harm, chronic pain, high rates of obscure operations, and many invasive diagnostic procedures) in illness behavior were registered in somatization and factitious disorder. This dimension seemed to include important emotional conflicts also in the doctor-patient relationship, and hinted at a serious risk of iatrogenic harm during the course of illness (Table 19.2).