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Causes and pathophysiology of Cushing's syndrome

Lynnette K Nieman, MD
Section Editor
André Lacroix, MD
Deputy Editor
Kathryn A Martin, MD


The diagnosis of Cushing's syndrome involves three steps: suspecting it on the basis of the patient's symptoms and signs, documenting the presence of hypercortisolism, and determining its cause. The last step requires an understanding of the classification and pathophysiology of the different types of Cushing's syndrome; these will be reviewed here. The clinical manifestations and diagnosis of Cushing's syndrome are discussed separately. (See "Epidemiology and clinical manifestations of Cushing's syndrome" and "Establishing the diagnosis of Cushing's syndrome" and "Establishing the cause of Cushing's syndrome".)


Pseudo-Cushing’s syndrome refers to physiologic hypercortisolism that can occur in several disorders other than Cushing's syndrome. Examples include:

Patients who are physically stressed, such as by a severe bacterial infection

Patients with severe obesity, especially those with visceral obesity or polycystic ovary syndrome

Patients with malnutrition, anorexia nervosa or with intense chronic exercise


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Literature review current through: Sep 2016. | This topic last updated: May 27, 2014.
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