Addisonian Crisis

Introduction

Addisonian crisis, also known as acute adrenal insufficiency or adrenal crisis is an endocrinology emergency with a high mortality rate. It occurs secondary to inadequate levels of adrenal hormone production in the adrenal cortex.

The adrenal cortex produces 3 main types of steroid hormones;

• Glucocorticoids (cortisol) in the zona fasiculata.

• Mineralocorticoids (aldosterone) in the zona glomerulosa.

• Androgens in the zona reticularis.

Adrenal failure can be acute (Addisonian crisis) or chronic and it’s causes can be primary or secondary.

• Primary adrenal failure a.k.a Addisons Disease (rare)

  • Autoimmune (80%), trauma, infection e.g TB, fungal, haemorrhage, malignancy, congenital

  • Loss of glucocorticoid and mineralocorticoid function.

• Secondary (common)

  • Exogenous suppression of hypothalamus-pituitary-adrenal axis, hypopituitarism

  • Loss of glucocorticoid function only

Acute adrenal insufficiency/Addisonian crisis leads to electrolyte derangement, metabolic acidosis and shock due to cortisol +/- aldosterone deficiencies. If left untreated it can be fatal. Therefore a high degree of suspicion is necessary.

Adrenal crisis must be considered in all unwell patients especially those who may be taking a prolonged course of glucocorticoids and have recently missed doses. Other acute stressors that may trigger an acute crisis in a person with either primary or secondary adrenal insufficiency include concurrent illnesses e.g. sepsis, gastroenteritis, surgery, myocardial infarction or trauma.

Differential Diagnosis

Clinical manifestations of glucocorticoid deficiency

• Anorexia, vomiting, weakness, hypotension (especially postural), shock (not responding to fluids), hypercalcaemia, hypoglycaemia.

Clinical manifestation of mineralocorticoid deficiency

• Dehydration, hyponatraemia, hypochloraemia, hyperkalaemia, normal anion gap metabolic acidosis (NAGMA), pre-renal AKI.

Clinical manifestations of Adrenal Crisis

• fever, confusion, refractory shock, hypotension, dehydration, nausea, vomiting, diarrhoea, abdo pain.

• Hypotension/Shock out of proportion to severity of current illness = key feature of adrenal crisis.