Chapter 54: Care of Patients with Pituitary and Adrenal Gland Problems

Priority Concepts:

• Fluid and electrolyte balance
• Cellular regulation
• Immunity

Pituitary Gland Overview:

• Divided into two lobes: anterior and posterior
• Anterior lobe: Synthesizes and releases hormones like:
  • Growth hormone (GH)
  • Thyroid-stimulating hormone (TSH)
  • Luteinizing hormone (LH)
  • Follicle-stimulating hormone (FSH)
  • Adrenocorticotropic hormone (ACTH)
  • Prolactin
• Posterior lobe: Stores and releases hormones like:
  • Oxytocin
  • Antidiuretic hormone (ADH, also known as vasopressin)

Hypopituitarism:

• Causes: Pathology on the hypothalamus or direct pathology affecting the pituitary gland, commonly a tumor
• Definition: Insufficient hormone production of the pituitary gland
• Life-threatening deficiencies: ACTH or TSH
• Symptoms: Vision changes, hormone-specific deficiencies (e.g., peripheral vision loss, fatigue, hypotension, hypothyroidism symptoms)
• Diagnostics: Baseline hormone levels, MRI with gadolinium enhancement
• Treatment: Surgical removal of mass, hormone replacement therapies (e.g., androgen, growth hormone, vasopressin/desmopressin)

Hyperpituitarism:

• Definition: Excessive production of hormones secreted by the pituitary
• Common causes: Pituitary adenoma
• Symptoms: Depend on which hormone is overproduced (e.g., acromegaly, gigantism, Cushing disease)
• Diagnostics: Lab tests, MRI with gadolinium enhancement
• Treatment: Surgical removal (hypophysectomy), pharmacological treatments (e.g., bromocriptine for prolactinomas), radiation therapy

Diabetes Insipidus (DI):

• New terms: Arginine vasopressin deficiency (AVPD) or resistance (AVPR)
• Causes: Trauma, medications (e.g., lithium, foscarnet), other underlying conditions
• Symptoms: Excessive dilute urine, hypernatremia, dehydration
• Diagnostics: 24-hour urine collection, low urine specific gravity, hypernatremia
• Treatment: Desmopressin (nasal spray, IV, or subq), fluid replacement, monitoring electrolytes

Syndrome of Inappropriate Antidiuretic Hormone (SIADH):

• Causes: Ectopic ADH production (e.g., small cell lung cancer), CNS disorders, medications (e.g., SSRIs), pulmonary diseases
• Symptoms: Hyponatremia, cerebral edema, headache, lethargy, seizures
• Diagnostics: Serum osmolality, sodium levels, urine osmolality
• Treatment: Fluid restriction, medications (e.g., conivaptan, tolvaptan), monitoring electrolytes, hypertonic saline if severe

Adrenal Gland Disorders:

Addison's Disease (Adrenal Insufficiency):

• Causes: Autoimmune disease, exogenous steroid use
• Symptoms: Hypotension, altered mental status, GI symptoms, fatigue, orthostatic hypotension, hyperkalemia, hyponatremia
• Diagnostics: ACTH stimulation test, MRI, CT
• Treatment: Fluid replacement, corticosteroids (hydrocortisone), monitoring electrolytes, tapering off steroids

Cushing's Disease/Syndrome:

• Causes: Prolonged high cortisol levels, usually due to medication or pituitary adenoma
• Symptoms: Hypertension, hyperglycemia, central obesity, moon face, buffalo hump
• Diagnostics: Cortisol levels (blood, urine, saliva), dexamethasone suppression test, MRI, CT
• Treatment: Surgical removal of tumor, radiation therapy, monitoring for complications (fluid overload, infections)

Hyperaldosteronism:

• Causes: Excess aldosterone production, adrenal adenoma
• Symptoms: Refractory hypertension, hypokalemia, metabolic alkalosis
• Diagnostics: Imaging (CT, MRI), suppression tests
• Treatment: Removal of adrenal gland(s), medication (e.g., spironolactone)