Epidemiology


Etiology

  • Sheehan syndrome: postpartum necrosis of the pituitary gland. Usually occurs following postpartum hemorrhage, but can also occur even without clinical evidence of hemorrhage.
    • During pregnancy, hypertrophy of prolactin-producing regions increases the size of the pituitary gland, making it very sensitive to ischemia.
    • Blood loss during delivery/postpartum hemorrhage → hypovolemia → vasospasm of hypophyseal vessels → ischemia of the pituitary gland → empty sella turcica on imaging

Pathophysiology

  • Hypopituitarism refers to deficiency of one or more anterior pituitary hormones
  • In addition to the aforementioned hormone deficiencies, patients with severe pituitary damage (panhypopituitarism) also present with deficiencies of posterior pituitary hormones:

Clinical features


Diagnostics


Treatment

  • Treat the underlying cause: For example, surgical resection of a pituitary adenoma.
  • Hormone Replacement Therapy: This is the cornerstone of treatment and is typically lifelong.
    • Glucocorticoids (hydrocortisone, prednisone): Replace for ACTH deficiency. This must be done FIRST before thyroid hormone replacement to prevent precipitating a life-threatening adrenal crisis.
    • Levothyroxine: Replace for TSH deficiency.
    • Sex Hormones: Testosterone for men; estrogen and progesterone for women.
    • Growth Hormone (somatropin): Used for children with GH deficiency and may be used in adults to improve body composition and quality of life.
    • Desmopressin (DDAVP): Used if there’s concomitant posterior pituitary damage leading to diabetes insipidus.