Diagnosing Cushing Syndrome
Answers to common questions about diagnosing cushing syndrome.
Questions on this page
How is Cushing syndrome diagnosed?
Evaluation may involve tests such as:
- Overnight dexamethasone suppression testing
- 24-hour urinary free cortisol
- Late-night salivary cortisol
The choice of test depends on the clinical situation.
Why can't one cortisol test diagnose Cushing syndrome?
Cortisol varies naturally throughout the day and can be affected by stress, medications and other conditions.
Diagnosis usually requires appropriate testing and interpretation in the clinical context.
What happens after Cushing syndrome is confirmed?
Further testing is performed to determine whether the excess cortisol is related to:
- ACTH-dependent disease
- Adrenal cortisol production
- Another source
Imaging may then be required to identify the underlying cause.