Cushing’s disease and Cushing’s syndrome are related conditions that involve excess cortisol production in the body, but they have distinct differences:
- Cushing’s disease specifically refers to a form of Cushing’s syndrome that is caused by a pituitary adenoma, which is a benign tumor in the pituitary gland.
- The pituitary adenoma in Cushing’s disease produces excessive amounts of adrenocorticotropic hormone (ACTH), which stimulates the adrenal glands to overproduce cortisol.
- The excessive ACTH production is usually the result of a noncancerous growth or tumor in the pituitary gland.
- Cushing’s disease accounts for the majority of cases of endogenous (internally caused) Cushing’s syndrome.
- Cushing’s syndrome is a broader term that encompasses all causes of excess cortisol production, whether or not it is due to a pituitary adenoma.
- It includes cases caused by adrenal tumors (adrenal Cushing’s syndrome) or prolonged use of corticosteroid medications (exogenous Cushing’s syndrome).
- Adrenal Cushing’s syndrome occurs when an adrenal gland tumor, either benign (adenoma) or malignant (carcinoma), overproduces cortisol independent of ACTH stimulation.
- Exogenous Cushing’s syndrome results from the prolonged use of corticosteroid medications, such as prednisone, which can suppress the body’s normal cortisol production and lead to an excess of exogenously administered cortisol or similar synthetic compounds.
- Other rare causes of Cushing’s syndrome include ectopic ACTH syndrome, where tumors in other parts of the body (e.g., lungs, pancreas) produce ACTH, leading to excess cortisol production.
In summary, Cushing’s disease is a specific type of Cushing’s syndrome caused by a pituitary adenoma and excessive ACTH production. Cushing’s syndrome is a broader term that encompasses all causes of excess cortisol production, including Cushing’s disease, adrenal tumors, and exogenous administration of corticosteroids.
Diagnosis and management of Cushing’s disease and Cushing’s syndrome require a comprehensive evaluation by healthcare professionals, including hormonal testing, imaging studies, and sometimes surgical intervention or medication adjustments, depending on the underlying cause.