Addison's Disease

• Primary cause:** Autoimmune adrenalitis (most common in developed countries), where the immune system attacks adrenal cortex cells.
• Other causes:** Infections (e.g., tuberculosis, HIV-associated opportunistic infections), adrenal haemorrhage, metastatic cancer, or genetic disorders (e.g., adrenal leukodystrophy).
• Pathophysiology:** Progressive destruction of the adrenal cortex leads to deficient cortisol (glucocorticoid) and aldosterone (mineralocorticoid) production, disrupting glucose metabolism, stress response, electrolyte balance, and blood pressure regulation.

Common symptoms:** Fatigue, weight loss, anorexia, nausea, abdominal pain, salt craving, and hyperpigmentation (especially in sun-exposed areas, skin folds, and mucous membranes).

Red-flag/severe symptoms:**

• Hypotension (especially orthostatic), syncope.
• Hyponatremia, hyperkalemia.
• Adrenal crisis: Acute hypotension, severe vomiting/diarrhoea, confusion, fever, and loss of consciousness—requires immediate medical intervention.

⁠Clinical assessment:** History and physical exam focusing on fatigue, hyperpigmentation, hypotension, and electrolyte abnormalities.

Laboratory tests:**

• Low morning serum cortisol.
• Elevated plasma adrenocorticotropic hormone (ACTH).
• ACTH stimulation test (blunted cortisol response confirms diagnosis).
• Electrolyte panels (hyponatremia, hyperkalemia).

Imaging:** Abdominal CT to assess adrenal gland structure (e.g., atrophy, calcifications, masses).

Pharmacological:**

• Glucocorticoid replacement: Hydrocortisone or prednisone.
• Mineralocorticoid replacement: Fludrocortisone.

Non-pharmacological:**

• Dietary sodium supplementation.
• Stress-dose steroid adjustment during illness, surgery, or trauma.
• Patient education on medication adherence and sick-day rules.

Adrenal crisis:** Life-threatening hypotension, shock, and death if untreated.
Chronic complications: Electrolyte imbalances, hypoglycemia, and increased susceptibility to infections.
Reduced quality of life due to persistent fatigue and need for lifelong medication.

Prevention:** No known preventive measures for autoimmune cases; early treatment of infections (e.g., TB) may reduce risk.

Follow-up:**

• Regular monitoring of electrolyte levels, blood pressure, and hormone levels.
• Annual assessment of replacement therapy adequacy.
• Patient counselling on emergency steroid use and medical alert identification.