Psychosis And Epilesy

Question 1

Ictal psychosis

Answer 1

Ictal psychosis occurs concurrent with the electrical activity and relates most commonly to visual or auditory illusions and hallucinations combined with affective changes, such as agitation or fear or paranoia. Other phenomena of partial epilepsy include depersonalization, derealisation, autoscopy, out of body experience, or a sense of “someone behind”. These symptoms often localize to the temporal lobe with activation of limbic and neocortical temporal areas. Prolonged ictal psychotic states are rare and may occur as a nonconvulsive status epilepticus with simple or complex partial or absence seizures. The onset may be sudden or gradual. Early diagnosis with an EEG is recommended, as is rapid termination of the seizure.

Question 2

Postictal psychosis

Answer 2

Postictal psychosis (PIP) occurs in 2–7.8% of epilepsy patients and is defined by hallucinations, delusions, and/or gross abnormalities of behaviour or affect, commencing up to seven days after a seizure. Abnormalities of mood predominate, rather than delusions of reference, perception, or persecution as in schizophrenia. Diagnostic criteria are:
(1) episode of psychosis within 1 week after a seizure(s);
(2) psychosis lasts > 15 h and < 3 months;
(3) delusions, hallucinations in clear consciousness, bizarre, or disorganized behaviour, formal thought
disorder, or affective changes; and
(4) no evidence of antiepileptic drug toxicity, nonconvulsive status epilepticus, recent head trauma,
alcohol, or drug intoxication or withdrawal, prior chronic psychotic disorder.
Markedly abnormal mood occurs in most PIP cases, including depressed affect, manic symptoms (e.g., grandiose delusions, hyper-religiosity), irritable and aggressive behaviour, and hallucinatory experiences. First rank (Schneiderian) symptoms of schizophrenia, such as voices commenting or thought insertion are rare in PIP. Negative symptoms are not prominent in PIP. It is important to note that there is a lucid period of up to a week - this lucidity is absent in non-convulsive status. Risk factors for postictal psychosis includes: family history of affective disorders, seizure clustering, bilateral temporal lobe pathology and a history of diffuse cerebral damage such as encephalitis or head injury.
Another differential diagnosis is a “postictal confusional state” in which the sensorium is altered. Postictal confusional states can occur as fugues or twilight states. Fugues can involve impaired consciousness, wandering and amnesia. The EEG can be normal. Twilight states also involve cognitive impairment, transient paranoia, and changes in perceptive experience.

Question 3

Interictal psychosis

Answer 3

Interictal Psychosis: A long history of uncontrolled seizures can lead to a chronic psychotic state (CIP) in more than 5% of patients, often with an insidious onset of paranoid delusions and hallucinations. CIP is closer in form to schizophrenia than PIP, because there is usually a less intense affective component, persecutory auditory hallucinations are common. Religiosity can occur. First rank (Schneiderian) symptoms involving disintegration of mental boundaries are usually absent in CIP. Thought disorder is uncommon in CIP. Although most authors have focussed on positive symptoms (delusions, hallucinations, referentiality), some have noted a higher incidence of negative symptoms—increasing isolation and decreasing socialization, overall downward cognitive, social, functional drift, affective blunting—in patients with temporal lobe epilepsy (31%) when compared to normal controls (8%).

Question 4

Forced normalisation

Answer 4

Forced normalization or ‘alternative psychosis’: Forced normalization remains controversial. The term is used to describe patients who develop psychosis or personality changes after treatment of their epilepsy and ‘normalisation’ of their EEG. Landolt introduced the concept with two cases who developed personality and mood changes, but not psychosis, in association with normalization of their EEGs. Although Landolt observed psychosis due to forced normalization in temporal lobe epilepsy, he most often observed it with absence epilepsy successfully treated with ethosuximide; however nine of the 12 patients with generalized epilepsy developed secondary psychomotor epilepsy, suggesting a diagnostic error. More recently, forced normalization was reported as an uncommon phenomenon in patients with chronic, medically refractory partial epilepsy whose seizures are controlled or reduced with medication.