What is Nelson's Syndrome?

Nelson's Syndrome occurs in some patients with Cushing's Disease (pituitary tumor making ACTH) after both adrenal glands are surgically removed (bilateral adrenalectomy). Without the adrenals, there is no cortisol to provide "feedback" to the pituitary. This causes the pituitary tumor to grow aggressively and overproduce ACTH.

Symptoms:

• Hyperpigmentation: The skin becomes very dark (bronze or black), especially on sun-exposed areas, scars, and skin folds. This is because ACTH also stimulates melanocytes (pigment cells).
• Pituitary Mass Effects: Headaches, vision loss (if the tumor compresses the optic nerves).

Why does it happen?

In the past, bilateral adrenalectomy was a common treatment for Cushing's Disease when pituitary surgery failed. Now, with better pituitary surgery and radiation, Nelson's Syndrome is rarer.

Treatment:

• Pituitary Surgery or Radiation: To shrink or destroy the tumor.
• Lifelong Hydrocortisone: Since the adrenals are gone, steroid replacement is mandatory.