Causes
| Cause | Frequency |
|---|---|
| Exogenous (medication-induced) | Most common overall — from long-term steroid use for other conditions |
| Pituitary adenoma (Cushing's disease) | Most common endogenous cause |
| Adrenal tumour | Less common |
| Ectopic ACTH-producing tumour | Rare — e.g. certain lung cancers |
Symptoms
- Central weight gain with thin arms and legs
- Round 'moon' face
- Purple abdominal stretch marks
- Easy bruising, thin skin
- Muscle weakness, especially proximal (difficulty rising from a chair)
- High blood pressure and blood sugar
- Osteoporosis
Diagnostic Approach
| Test | Purpose |
|---|---|
| 24-hour urine cortisol | Screening test — elevated in Cushing's |
| Late-night salivary cortisol | Should be low at night — elevated suggests Cushing's |
| Low-dose dexamethasone suppression test | Failure to suppress cortisol confirms Cushing's |
| ACTH level | Distinguishes pituitary/ectopic (high ACTH) from adrenal (low ACTH) causes |
| Pituitary MRI or adrenal CT | Locates the source once biochemically confirmed |
Steroid-Induced Cushing's Is ReversibleIf Cushing's syndrome results from prescribed steroid medication, gradually reducing the dose (under medical supervision, never abruptly) typically resolves the features over months, though this must be balanced against the condition the steroids were treating.
Is Cushing's syndrome the same as Cushing's disease?
Cushing's disease specifically refers to a pituitary tumour causing excess ACTH and cortisol — a subtype of the broader Cushing's syndrome, which includes all causes of excess cortisol.
Can Cushing's syndrome be cured?
Yes, if caused by a removable tumour (pituitary or adrenal surgery), or if medication-induced steroids can be safely tapered. Response to treatment is often good with appropriate management.
Medical Disclaimer: This page is for general education only and does not replace professional medical advice. Always consult a qualified healthcare provider.