Delusional disorder is characterized by having at least how many delusions?

Delusional disorder is indeed characterized by the presence of at least one delusion. A delusion is defined as a firmly held belief that is not based in reality, and in the context of delusional disorder, these beliefs persist for at least one month. The nature of the delusions can vary widely, including themes such as persecution, grandeur, jealousy, or somatic concerns, but the key criterion for diagnosis is the presence of a single delusion. This specificity helps differentiate delusional disorder from other psychiatric conditions where multiple delusions might be present, thus making it essential to recognize that a minimum of one sustained delusion is necessary for the diagnosis.