Diagnosis and treatment of a severe psychotic illness in a man with dual severe sensory impairments caused by the presence of Usher syndrome.

The present paper reports the case history of a 50-year-old man born with Usher syndrome, who developed a psychotic illness later in life, to illustrate the specific diagnostic problems, and the value of direct observation and a detailed assessment of communication. The subject had had a significant hearing impairment since birth, problems with balance and developed retinitis pigmentosa, leaving him with progressively limited vision in adult life. A pattern of bizarre and aggressive behaviour, and a disintegration in his ability to communicate using signs developed over 3 months. An initial diagnosis of depression was made, but it later became clearer that the subject had developed a psychotic illness. This condition responded well to a combination of antidepressant and antipsychotic medication. The possible association between Usher syndrome and psychotic illness is also discussed.