Pathophysiology: Endocrine Disorders Overview

Endocrine Disorders Overview

• Endocrine disorders involve dysfunction of glands responsible for hormone production.
• Pituitary, thyroid, and adrenal glands are key endocrine organs studied.
• Textbook, "Pathophysiology for the Health Professions," 4th edition, 2011, chapter 25 (pages 545-572) provides details.
• Lecture 11 covers specific disorders.

Pituitary Gland Disorders

• Benign adenomas: Most common cause in pituitary disorders.
  • Make up over 10% of intracranial tumors.
  • Occur primarily in people aged 30-50.
  • Cause pressure (increased intracranial pressure) on the brain from growth.
  • Can cause various hormone issues depending on which part of the pituitary gland is affected including excess or deficit of hormones.
• Untreated adenomas can lead to panhypopituitarism (complete loss of pituitary function).
• Tumors are often removed by surgery or radiation; hormone replacement is commonly required.
• Vascular thrombosis and infarction (blood clots or blockages) associated with pregnancy or other cardiovascular issues can cause hypopituitarism.
• Hypothalamic disorders (tumors or infections) affect pituitary function.

Growth Hormone Disorders

• Dwarfism (short stature): Results from a growth hormone (GH) or growth hormone-releasing hormone (GHRH) deficiency.
  • Patients usually have normal intelligence and body proportions, but skeletal maturation and puberty may be delayed.
  • Replacement therapy may be possible before the closure of the epiphyses.
• Gigantism (tall stature): Results from excess GH before puberty and the fusion of epiphyses—the growth plates.
• Acromegaly: Excess GH secretion in adults (after epiphyses closure); pituitary adenomas.
• Symptoms of acromegaly: Enlarged bones, hands, and feet, changed facial features (protruding mandible, large tongue), and carpal tunnel syndrome.
• Complications: Often related to diabetes, and hypertension, and cardiovascular issues.

Antidiuretic Hormone (ADH) Disorders

• Diabetes Insipidus: ADH deficiency; causes excessive urination (polyuria) and extreme thirst(polydipsia).
  • May be temporary or chronic.
  • Can be caused by head injury, surgery, genetic conditions or linked to electrolyte imbalances or drugs.
• Inappropriate ADH Syndrome (SIADH): Excessive ADH; causes the kidneys to retain too much water, resulting in low sodium levels in the blood (hyponatremia).
  • May be temporary and caused by stress, certain medications, or cancer.

Thyroid Gland Disorders

• Thyroid hormones (T3 and T4): Crucial for metabolism, oxygen consumption, and mental development

• Goiter: Enlargement of the thyroid gland.

  • Endemic goiter: Iodine deficiency in the soil and food, common in mountainous areas or near Great Lakes. Lowered T3 and T4 production stimulates TSH from the pituitary.
  • Sporadic goiter: Certain foods (goitrogens) or medications block thyroid hormone production, similar compensatory increase in TSH

• Hyperthyroidism: Overactive thyroid gland.

  • Graves' disease: Autoimmune disorder; antibodies stimulate TSH receptors.
  • Signs: Hypermetabolism (weight loss, increased heart rate), exophthalmos (bulging eyes), and increased sympathetic nervous system (anxiety, sweating).
  • Thyrotoxic crisis (thyroid storm): Severe hyperthyroidism; infection or trauma often trigger it.
    • Life-threatening conditions—delirium, hyperthermia, tachycardia, heart failure

• Hypothyroidism: Underactive thyroid gland.

  • Hashimoto's disease: Autoimmune destruction of the thyroid tissue
  • Myxedema: Severe hypothyroidism in adults—causes non-pitting edema (swelling), thick tongue, and decreased mental functions.
  • Cretinism: Congenital hypothyroidism (from birth); severe intellectual disability (mental retardation.
  • Symptoms of hypothyroidism: Slow metabolism, tiredness, weight gain, cold intolerance, dry skin, constipation, delayed puberty, memory loss.

Diagnostic Tests for Thyroid Disorders

• Serum blood levels of T3, T4, and TSH.
• Radioactive iodine uptake test.
• Scans (ultrasound, CT, MRI) to see if there are nodules.
• Antibody assays to confirm diagnoses.

Adrenal Gland Disorders

• Adrenal medulla disorders:

  • Pheochromocytoma: Benign tumor of the adrenal medulla that secretes epinephrine and norepinephrine.
    • May be bilateral or unilateral.
    • Leads to high blood pressure.

• Adrenal cortex disorders:

  • Cushing's syndrome: Excess cortisol production (from various causes).
    • Symptoms: Moon face, Buffalo hump, abdominal obesity, thinning extremities, fragile skin, redness of skin. Increased risk of infection.
    • Treatment depends on the underlying cause.
  • Addison's disease: Adrenocortical insufficiency.
    • Causes from different causes.
    • Symptoms: Chronic fatigue, weight loss, hypotension, nausea, vomiting, darkening of the skin, low blood sugar, decreased stress response, abdominal pain.
    • Treatment includes replacement therapy with necessary hormone supplements.

This quiz covers the overview of endocrine disorders with a focus on the dysfunction of glands such as the pituitary, thyroid, and adrenal glands. Utilizing information from 'Pathophysiology for the Health Professions', this quiz also delves into specific conditions, including benign adenomas and their consequences. Test your knowledge on the key aspects and treatment options related to these critical endocrine functions.