Adrenal Disorders in Children

Adrenal Disorders in Children

• Adrenal glands are located above the kidneys
• Divided into two sub-organs: cortex and medulla
• Adrenal cortex secretes steroid hormones: glucocorticoids, mineralocorticoids, and androgens
• Adrenal medulla secretes catecholamines (epinephrine/adrenaline and norepinephrine)

Adrenal Gland Function

• Mineralocorticoids: regulate sodium retention and potassium loss, balancing body fluid
• Glucocorticoids: act as anti-inflammatory agents and affect metabolism
• Androgens: regulate growth/development of genitalia and puberty
• Adrenaline (epinephrine): increases heart rate and blood pressure
• Norepinephrine: constricts arterioles

Glucocorticoids (Cortisol)

• Crucial for many physiological processes, including cardiovascular function and blood pressure regulation
• Influences carbohydrate metabolism, maintaining normal glucose levels
• Plays a role in immune function, reducing inflammation and suppressing the immune system
• Cortisol levels typically peak in the early morning and are lowest in the evening. This is a typical pattern.

Aldosterone

• A mineralocorticoid regulating sodium and potassium balance
• Plays a key role in the renin-angiotensin-aldosterone system (RAAS) which regulates blood pressure.
• Kidneys are major participants in the regulation process

Adrenal Disorders

• Primary adrenal insufficiency:
  • Hereditary: Congenital adrenal hyperplasia, others
  • Autoimmune: Addison's disease, polyglandular autoimmune syndromes (type 1 & 2)
  • Infectious: Tuberculosis, systemic fungal infections, HIV, CMV
  • Medications: reduced steroid synthesis (e.g., ketoconazole), increased steroid metabolism (e.g., rifampin)
  • Miscellaneous: hemorrhage, Triple A syndrome (Allgrove syndrome)
• Secondary/Tertiary adrenal insufficiency:
  • Isolated ACTH deficiency, panhypopituitarism (congenital or acquired)
  • Hypothalamic/pituitary disorders, tumors, surgery, radiation therapy (possibly infections related to CNS)
  • Withdrawal from glucocorticoid therapy, inadequate replacement, infant born to a mother on steroids, surgical tumor removal (Cushing's disease)

Congenital Adrenal Hyperplasia (CAH)

• Autosomal recessive condition
• Most common cause of primary adrenal insufficiency
• High incidence of 21-hydroxylase deficiency which affects the ability to produce cortisol and aldosterone.
• Neonatal screening for this is recommended.
• Prenatal therapy is essential to prevent genital problems in affected females

Addison's Disease

• Rare autoimmune disorder
• Autoimmune destruction of adrenal glands
• Leads to inadequate production of adrenal hormones causing insufficiency
• Clinical symptoms include:
  • Fasting hypoglycemia
  • Nausea/vomiting and diarrhea
  • Weight loss/severe anorexia
  • Fatigue, lethargy, muscle weakness
  • Hyperpigmentation (darkening of skin)
  • Hypotension, shock, even death

Cushing's Syndrome

• Excess cortisol secretion, potentially from:
  • ACTH-secreting tumor of the pituitary
  • Neoplasm within adrenal cortex
  • Ectopic ACTH secretion by a malignant growth outside the adrenal gland
  • Prolonged steroid use
• Clinical presentation includes:
  • Truncal obesity
  • Moon face
  • Buffalo hump (fat accumulation in the upper back)
  • Acne, hirsutism
  • Abdominal striae (stretch marks)
  • Hypertension
  • Psychiatric disturbances
  • Osteoporosis
  • Amenorrhea
  • Diabetes

Diagnostic Workup

• Medical history and physical examination are crucial
• Measurements including blood pressure, serum electrolytes, glucose, and cortisol levels
• Imaging tests and hormonal assessments to confirm the diagnosis
• ACTH stimulation tests

Treatment

• Treatment for adrenal disorders varies significantly based on the underlying cause.
• Medications: hydrocortisone, fludrocortisone
• Possible surgery for neoplasia