Cushing Syndrome

Persistent cortisol excess produces Cushing syndrome; a single stress-related cortisol elevation does not. Cushing disease is the specific pituitary ACTH-producing form, whereas the broader syndrome also includes ectopic ACTH secretion, adrenal cortisol production, and exposure to prescribed glucocorticoids. The diagnostic sequence is deliberate: first establish endogenous hypercortisolism, then measure ACTH to choose the adrenal or ACTH-dependent pathway, and only then localize the source. Before ordering a biochemical test, reconcile every steroid exposure, including oral, inhaled, topical, nasal, and injected preparations. Exogenous glucocorticoids are the most common overall cause and can make an elaborate endocrine workup unnecessary. A cluster such as new hypertension or diabetes with proximal weakness, easy bruising, facial plethora, or broad violaceous striae is more persuasive than weight gain alone. The nurse’s early contribution is to recognize that pattern, identify exposures and confounders, and ensure that an abnormal screen leads to confirmation rather than a premature label.