Dexamethasone suppression test results in delusional versus nondelusional depression: preliminary evidence of distinct clinical entities.

Two patients with major affective disorder--one unipolar and one bipolar--exhibited normal DSTs while psychotically depressed (mood congruent delusions), yet exhibited nonsuppression on the DST in the course of subsequent separate nonpsychotic depressive episodes. If valid, these results may provide further evidence for considering psychotic and nonpsychotic depression as clinically distinct entities.