Delusional disorder: the recognition and management of paranoia.

Delusional disorder, the contemporary conceptualization of paranoia, is an uncommon condition characterized by the presence of one or more nonbizarre delusions and the relative absence of associated psychopathology. The delusions concern experiences that can conceivably occur in real life, such as being followed (persecutory type), having a disease (somatic type), being loved at a distance (erotomanic type), having an unfaithful sexual partner (jealous type), and possessing inflated worth, power, identity, or knowledge (grandiose type). The diagnosis requires at least 1 month's duration of the delusion; impact on functioning that is consistent with the delusion or its ramifications; generally normal appearance and behavior; and the exclusion of schizophrenia, mood disorder, substance-induced toxicity, and medical disease. Typically, patients are unaware of the psychiatric nature of the condition. They may present to internists, dermatologists, plastic surgeons, lawyers, or the police rather than to psychiatrists. Although the prevalence is low, delusional disorder is not rare. Age at onset is usually middle or late adulthood, and the course is variable. Familial transmission is suspected, and comorbidity (frequently mood disorders) may exist. Successful management is difficult and may include hospitalization, pharmacotherapy, and certain forms of psychotherapy.