Adrenal & Pituitary Disorders

The pituitary gland sits at the base of the brain and serves as the master regulator of the endocrine system. It produces hormones that control the thyroid, adrenal glands, gonads, growth, and water balance. Dysfunction here can produce a cascade of hormonal deficiencies or excesses affecting nearly every organ system.

Pituitary tumors (adenomas) are almost always benign. Functioning adenomas secrete hormones autonomously — the most common are prolactinomas (excess prolactin), causing infertility, irregular periods, and galactorrhea. Others produce excess growth hormone (acromegaly) or ACTH (Cushing’s disease). Non-functioning adenomas cause symptoms through mass effect on adjacent structures.

Cushing’s syndrome results from prolonged exposure to excess cortisol. Characteristic features include central weight gain, a rounded “moon” face, a fatty hump at the back of the neck, easy bruising, purple stretch marks, muscle weakness, hypertension, and diabetes. When caused by a pituitary tumor overproducing ACTH, it is called Cushing’s disease.

The adrenal glands sit atop each kidney. The adrenal cortex produces cortisol (stress hormone), aldosterone (regulates blood pressure and sodium), and sex hormone precursors. The adrenal medulla produces adrenaline and noradrenaline — the “fight or flight” hormones.

Adrenal insufficiency occurs when the adrenal glands cannot produce adequate cortisol. Primary adrenal insufficiency (Addison’s disease) results from destruction of the adrenal cortex — most commonly autoimmune. Secondary adrenal insufficiency results from pituitary failure to produce ACTH.

Symptoms include profound fatigue, weight loss, low blood pressure, salt craving, and nausea.

Primary aldosteronism is caused by excess aldosterone production, leading to hypertension (often resistant to medications), low potassium, and increased cardiovascular risk. It accounts for approximately 10% of all hypertension cases.

A pheochromocytoma is a tumor of the adrenal medulla that produces excess catecholamines (adrenaline and noradrenaline). It classically causes episodic hypertension, headache, sweating, and palpitations. It is surgically curable and is an important diagnosis not to miss.

An adrenal incidentaloma is an adrenal mass discovered incidentally on imaging performed for another reason. They are found in approximately 5% of CT scans in adults. The evaluation focuses on two questions: Is it hormonally active? Is it malignant? Most are benign and non-functioning — but systematic evaluation is essential.