Frequency of causes of Cushing syndrome

Relative prevalence of various causes of Cushing syndrome in 630 patients (146 consecutive patients seen at Vanderbilt University Medical Center before 1993 and published reports describing 484 patients). The prevalence of pseudo-Cushing syndrome depends upon the individual clinician's threshold of clinical suspicion; in our experience, it is very rare. The relative prevalence of various causes of Cushing syndrome among children and adolescents may differ somewhat from that of adults. The ectopic ACTH syndrome, for example, is less common in children.