TOXOINFECTIVE PSYCHOSES. - Mental syndromes that arise in the course of general diseases and of infectious diseases not particularly localized to the nervous system, attributable to the action of autotoxins (renal insufficiency, hepatic insufficiency, deficiency states, endocrinopathies, etc.) and of bacterial toxins (febrile diseases in general).
Thus delimited, t.i. psychoses correspond to Bonhoeffer's "symptomatic psychoses" and do not include the "toxiphrenias," or psychoses from exogenous intoxications (alcohol, narcotics, occupational intoxications: phosphorus, lead, etc.) which may be approached to them in certain pathogenetic and clinical aspects. Symptomatic psychoses and toxiphrenias have a common causal basis (toxic etiology in the broad sense) extraneous to the individual constitution; hence the designation of exogenous psychoses (or acquired, according to Bleuler) to distinguish them from endogenous ones (that is, intimately bound to constitutional factors). However, in the morbid picture provoked by a toxic agent there is always glimpsed an undeniable, though variously assessed, influence of endogenous factors, so that not all authors agree in accepting a definition of this kind. This interference is deduced from the small number of cases in which a symptomatic psychosis intervenes in comparison with the high percentage with which the general disease that produced it presents itself; furthermore from the diversity of the psychic pictures that one and the same cause can provoke and from the variety of morbid agents that can trigger one and the same psychic syndrome. In other words, a given traumatic, toxic, or infective cause, other conditions being equal (that is, intensity, duration, etc.), provokes a psychosis only in certain individuals (who therefore appear constitutionally predisposed), and the symptoms presented by one individual can be very different from those presented by another, while the same symptoms can present themselves as the effect of quite distinct morbid causes: this would signify that the development and the clinical manifestations of a symptomatic psychosis are largely conditioned by individual factors (constitutional predisposition). Thus, a slight elevation of fever triggers in some a violent delirium, while many tolerate high temperatures without presenting any symptom; acute alcoholic intoxication (drunkenness) can manifest itself in very different ways (euphoria, depression, excitement, torpor), while an alcoholic delirium, a uremic one, a typhoid one, can sometimes be indistinguishable. The influence of a constitutional predisposition appears even more evident from the observation in certain individuals of one and the same psychic picture that presents itself several times in the course of their life as the effect of different morbid agents. Sometimes a familial "reactive" predisposition is recognizable, in the sense that in several members of a family the onset of symptomatic psychoses is observed, which may even assume a similar appearance.
The role of endogenous and exogenous factors has given rise to the most diverse interpretations and classifications of t.i. psychoses and constitutes one of the central problems of psychiatry. Some authors admit an acquired predisposition in the course of life as the effect of previous diseases that would have prepared the ground for the symptomatic psychosis,
but this is not admissible in all cases.
Bonhoeffer explains the lack of relation between cause
and effect (that is, between morbid agent and symptom) with his
"theory of exogenous reaction"; intoxications or
infections would give rise to metabolic toxins ("meta-toxin" of Kraepelin) not specific to the initial morbid
episode, toxins that would represent the direct
causes of the "syndromes" or elective types of the exogenous
reaction. The psychic pictures thus designated are not, for
this reason, pathognomonic of a determined morbid
form, but are common to the total group of exogenous
psychoses and very different from those observed in
endogenous psychoses (that is, bound to constitutional factors). The
elective types of exogenous reaction, according to Bonhoeffer, are:
clouding of consciousness, acute delirium, amenia, hallucinosis,
amnesic twilight states, etc. The influence of endogenous
factors on the development and the clinical manifestations of
symptomatic psychoses is instead, according to others, sufficiently
important to invalidate the classification of psychoses
according to exogenous and endogenous cause, and some (Kleist)
propose a classification according to the type of
symptoms.
Stertz has attempted a solution of the problem,
proposing a classification on causal and
symptomatic elements at the same time; he recognizes, in the psychic
symptomatology provoked by exogenous causes, fundamental
symptoms (or obligatory) and accessory symptoms (or facultative).
While the former would be directly caused by the morbid
agent, the latter instead would derive from a pathological
constitutional predisposition made manifest through the
effect of the morbid agent. It is to be observed that the fundamental
or obligatory symptoms of Stertz are the same that
Bonhoeffer describes as elective of the exogenous reaction
and according to the "symptomatic" classification of Kleist they
would be the "heteronymous" symptoms. The facultative symptoms of
Stertz are instead those that characterize the
endogenous psychoses and that according to the symptomatic classification of
Kleist would be "homonymous" symptoms.
The most frequent and most important symptoms of t.i.
psychoses are: disturbance of consciousness, delirium, alteration
of psychomotor activity. These symptoms can present themselves in various
gradations and combinations, thus giving rise to the various
syndromes (stuporous, delirious, amenial, etc.) described
by authors as typical of these affections. The disturbance
of consciousness is usually the cardinal symptom: the patient
appears "confused," lacking in attentive concentration and
in the possibility of critical judgment, completely disoriented;
associations are slowed and incorrect, and there is the formation of delusional convictions, fed by illusions and
hallucinations. The delirium is fragmentary and variable, of
usually terrifying content (fearful visions, bestial cries,
etc.) and arouses a profound alteration of the psychomotor
mechanisms that can manifest itself in an increase of the
motor impulse up to a most violent agitation, in
a slowing down to total arrest. These are the
symptoms that predominate in the syndromes described as
"elective of the exogenous reaction" of Bonhoeffer.
The prognosis is usually linked to that of the general
disease, and the recovery of the latter is in fact followed, in the
majority of cases, by the disappearance of the psychic
symptomatology. Sometimes, however, psychopathic forms
(post-psychotic states) of more or less long duration remain. Therapy
must be essentially directed against the general
disease.