Definition of Cushings syndrome Cushings syndrome comprises the symptoms and signs associated with prolonged exposure to inappropriately elevated levels of free plasma glucocorticoids The use of the term glucocorticoid in the definition covers both endogenous(cortisol) and exogenous(e.g prednisolone, dexamethasone)excess.Definition of Cushing’s Syndrome • Cushing's syndrome comprises the symptoms and signs associated with prolonged exposure to inappropriately elevated levels of free plasma glucocorticoids. • The use of the term glucocorticoid in the definition covers both endogenous (cortisol) and exogenous (e.g., prednisolone, dexamethasone) excess