Case 15: A teenager who hears messages from the traffic lights

01The case

A 19-year-old is brought to the psychiatric clinic by his parents, who are very worried about how he has behaved over the last two weeks. He looks around him as if puzzled, shuts himself in his room, does not sleep, laughs for no clear reason and has several times been heard talking to himself. He will not go out: the traffic lights send him unpleasant messages, he says, and people stare at him with ill intent. More than once he has stopped strangers in the street to ask why they are following him.

02Summary

Diagnosis

An acute psychosis with polymorphic features, a first psychotic episode: in ICD-10 an acute polymorphic psychotic disorder, one of the acute and transient psychotic disorders. ICD-11 keeps the group: psychotic symptoms that come on within two weeks, change quickly in kind and intensity, and last no more than three months.

What points to it

• Delusional mood: the perplexed look, a sense that something is going on that he cannot name.
• Delusions of reference (the traffic lights carry messages for him) and of persecution (people stare and follow him).
• Very probably auditory pseudo-hallucinations: he laughs and talks to himself. A pseudo-hallucination is a voice heard inside the head rather than through the ears; here it is still a psychotic symptom.
• His behaviour is driven by the delusions: he stays in, and confronts strangers.
• Two weeks from the first signs to the full picture: an acute onset.

What else it could be

A first episode, especially with florid symptoms, says little about the long-term diagnosis; in time schizophrenia or schizoaffective disorder is the most likely outcome. At his age ask about cannabis and stimulants and do a drug screen, and look for a physical cause as in any first psychosis.

Management

• Admission, an antipsychotic at a low starting dose, and a check of weight, glucose and lipids.
• Referral to an early intervention in psychosis team where one exists.
• Psychoeducation for him and his family. In a first episode this matters most for whether he keeps taking treatment after discharge and avoids relapse.
• Family intervention and cognitive behavioural therapy for psychosis.
• Treatment continued for at least one to two years, then reduced only gradually and under review.

Outlook

Uncertain. The acute onset and the short time to the full picture are good signs, but a first episode at 19 may prove to be the start of schizophrenia.