F23.9 Acute And Transient Psychotic Disorder

Systematic clinical information that would provide definitive guidance on the classification of acute psychotic disorders is not yet available, and the limited data and clinical tradition that must therefore be used instead do not give rise to concepts that can be clearly defined and separated from each other. In the absence of a tried and tested multiaxial system, the method used there to avoid diagnostic confusion is to construct a diagnostic sequence that reflects the order of priority given to selected key features of the disorder. The order of priority used here is:

(a) an acute onset (within 2 weeks) as the defining feature of the whole group;
(b) the presence of typical syndromes;
(c) the presence of associated acute stress.

The classification is nevertheless arranged so that those who do not agree with this order of priority can still identify acute psychotic disorders with each of these specified features.

It is also recommended that whenever possible a further subdivision of onset be used, if applicable, for all the disorders of this group. Acute onset is defined as a change from a state without psychotic features to a clearly abnormal psychotic state, within a period of 2 weeks or less. There is some evidence that acute onset is associated with a good outcome, and it may be that the more abrupt the onset, the better the outcome. It is therefore recommended that, whenever appropriate, abrupt onset (within 48 hours or less) be specified.

The typical syndromes that have been selected are first, the rapidly changing and variable state, called here "polymorphic", that has been given prominence in acute psychotic states in several countries, and second, the presence of typical schizophrenic symptoms.

Associated acute stress can also be specified, with a fifth character if desired, in view of its traditional linkage with acute psychosis. The limited evidence available, however, indicates that a substantial proportion of acute psychotic disorders arise without associated stress, and provision has therefore been made for the presence or the absence of stress to be recorded. Associated acute stress is taken to mean that the first psychotic symptoms occur within about 2 weeks of one or more events that would be regarded as stressful to most people in similar circumstances, within the culture of the person concerned. Typical events would be bereavement, unexpected loss of partner or job, marriage, or the psychological trauma of combat, terrorism, and torture. Long-standing difficulties or problems should not be included as a source of stress in this context.

Complete recovery usually occurs within 2 to 3 months, often within a few weeks or even days, and only a small proportion of patients with these disorders develop persistent and disabling states. Unfortunately, the present state of knowledge does not allow the early prediction of that small proportion of patients who will not recover rapidly.

These clinical descriptions and diagnostic guidelines are written on the assumption that they will be used by clinicians who may need to make a diagnosis when having to assess and treat patients within a few days or weeks of the onset of the disorder, not knowing how long the disorder will last. A number of reminders about the time limits and transition from one disorder to another have therefore been included, so as to alert those recording the diagnosis to the need to keep them up to date.

The nomenclature of these acute disorders is as uncertain as their nosological status, but an attempt has been made to use simple and familiar terms. "Psychotic disorder" is used as a term of convenience for all the members of this group with an additional qualifying term indicating the major defining feature of each separate type as it appears in the sequence noted above.

Diagnostic Guidelines

None of the disorders in the group satisfies the criteria for either manic or depressive episodes, although emotional changes and individual affective symptoms may be prominent from time to time.

These disorders are also defined by the absence of organic causation, such as states of concussion, delirium, or dementia. Perplexity, preoccupation, and inattention to the immediate conversation are often present, but if they are so marked or persistent as to suggest delirium or dementia of organic cause, the diagnosis should be delayed until investigation or observation has clarified this point. Similarly, disorders in F23 should not be diagnosed in the presence of obvious intoxication by drugs or alcohol. However, a recent minor increase in the consumption of, for instance, alcohol or marijuana, with no evidence of severe intoxication or disorientation, should not rule out the diagnosis of one of these acute psychotic disorders.

It is important to note that the 48-hour and the 2-week criteria are not put forward as the times of maximum severity and disturbance, but as times by which the psychotic symptoms have become obvious and disruptive of at least some aspects of daily life and work. The peak disturbance may be reached later in both instances; the symptoms and disturbance have only to be obvious by the stated times, in the sense that they will usually have brought the patient into contact with some form of helping or medical agency. Prodromal periods of anxiety, depression, social withdrawal, or mildly abnormal behaviour do not qualify for inclusion in these periods of time.