A person of 35 years is having firm belief about infidelity involving the spouse. And he never allow her to go out of home alone. He often locks his house, while going office. Inspite of all this he is persistantly suspicious about her character. The probable diagnosis is-

D i.e. Othello Syndrome This person is having disorder as he is having persistent delusion of infidelity without other personality disturbance, and hallucination (so schizophrenia is ruled out). Delusional disorders are differentiated from Schizophrenia by presence of systemetic delusions (Bizarre in Schizophrenia) with absence of hallucinations, near nonnal personality (only disturbed in delusional area), & contact with reality (only disturbed in delusional area)Q.