<prompt> Nihilistic delusions seen in: RepeatDepressionManiaSchizophreniaOCD  <response>: Ans: A Depression Ref: Kaplan Sadocks Synopsis of Psychiatry. 10th editionExplanation:Delusion is one of the psychotic symptoms seen in several disorders see previous question.Delusion is false, unshakable belief held with extraordinary conviction.Nihilistic delusion is a type of delusion, characterized by a false belief that everything will come to an end including ones life or lost everything including ones body parts.It is seen in severe depression.Hypochondriac delusion is a false belief that one has an incurable illness.Cotrad syndrome: Presence of both nihilistic and hypochondriac delusions, seen in severe depression. Other delusions seen in depression are:Delusion of hopelessnesshelplessness worthlessness.Delusion of guilt marker of suicidality.Mania - Delusion of grandiositySchizophrenia - Bizarre delusions, delusion of persecutionreference. 