aetiology
Last reviewed 07/2023
Most cases are iatrogenic, resulting from the therapeutic administration of supraphysiological doses of glucocorticosteroids or adrenocortiocotrophin.
Spontaneous Cushing's syndrome may be due to:
- Cushing's disease - 66% of such causes
- ectopic ACTH secretion - 11% - most frequently asssociated with small cell carcinoma of the bronchus; less often, carcinoid tumours of the lungs, thymus, pancreas, very rarely islet cell tumours and Wilms tumours
- adrenal adenoma - 9% secrete cortisol
- adrenal carcinoma - 7% secrete cortisol
- pseudo Cushings - 5%, excess cortisol production in association with alcohol or severe depressive psychosis
- macrondular adrenal hyperplasia - rare
- ectopic secretion of corticotrophin releasing factor - CRH - rare