What are the diagnostic steps for adrenal crisis?

Diagnosing Adrenal Crisis

Adrenal crisis is a life-threatening emergency characterized by acute adrenal insufficiency requiring immediate diagnosis based on clinical presentation, followed by prompt treatment with intravenous hydrocortisone 100mg and fluid resuscitation to prevent mortality. 1

Clinical Presentation and Initial Assessment

Key Clinical Features to Identify

• Hypotension (often refractory to fluid resuscitation)
• Nausea and vomiting
• Severe fatigue or weakness
• Abdominal pain
• Fever
• Altered mental status
• Hypoglycemia
• Electrolyte abnormalities (hyponatremia, hyperkalemia)

Laboratory Findings Suggestive of Adrenal Crisis

• Low serum cortisol (often <100 nmol/L) 2
• Electrolyte disturbances:
  • Primary adrenal insufficiency: ↓Na, ↑K
  • Secondary adrenal insufficiency: Generally normal electrolytes 1
• ACTH levels:
  • Primary adrenal insufficiency: High ACTH
  • Secondary adrenal insufficiency: Low ACTH 1

Diagnostic Algorithm for Adrenal Crisis

1. Immediate Assessment

   • Recognize clinical presentation (hypotension, nausea, vomiting, abdominal pain)
   • Check vital signs with focus on blood pressure
   • Assess for precipitating factors (infection, trauma, surgery, medication discontinuation)

2. Urgent Laboratory Testing

   • Draw blood for baseline cortisol level before treatment
   • Measure ACTH level (to differentiate primary vs. secondary)
   • Check electrolytes (sodium, potassium)
   • Complete blood count and comprehensive metabolic panel
   • Blood glucose level

3. Diagnostic Confirmation

   • A low baseline cortisol (<100 nmol/L) with raised ACTH can be sufficient to diagnose primary adrenal insufficiency 2
   • For confirmatory testing (when patient is stable):
     • Cosyntropin (Synacthen®) stimulation test
     • Insulin tolerance test (gold standard for secondary adrenal insufficiency) 2

Important Diagnostic Considerations

Differentiating Primary vs. Secondary Adrenal Insufficiency

Type	ACTH Level	Cortisol Level	Electrolytes	Hyperpigmentation
Primary	High	Low	↓Na, ↑K	Present
Secondary	Low	Low	Generally normal	Absent
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Common Pitfalls in Diagnosis

• Delaying treatment to wait for laboratory confirmation
  • Critical point: Treatment should not be delayed for laboratory confirmation if adrenal crisis is suspected clinically 3
• Missing the diagnosis due to nonspecific symptoms
  • Symptoms often overlap with other acute illnesses 4
• Failing to consider adrenal crisis in patients on chronic glucocorticoid therapy
  • Glucocorticoid-induced adrenal insufficiency is the most prevalent form of adrenal insufficiency 4

High-Risk Scenarios Requiring Vigilance

• Patients with known adrenal insufficiency presenting with acute illness
• Recent glucocorticoid withdrawal
• Patients with autoimmune disorders (risk for autoimmune adrenalitis)
• Patients with hypothalamic-pituitary tumors or surgery
• Patients presenting with unexplained shock, especially with electrolyte abnormalities 5

Immediate Management After Diagnosis

• Administer 100mg hydrocortisone IV bolus immediately
• Follow with continuous infusion of 200mg/24h or 50mg every 6 hours until stabilized
• Rapid IV isotonic saline administration for volume resuscitation 1

Underlying Cause Investigation

After stabilization, a strategic approach to determine the underlying cause should include:

• Adrenal antibody testing (for autoimmune adrenalitis)
• Imaging studies (CT/MRI of adrenal glands or pituitary)
• Assessment for tuberculosis or fungal infections
• Review of medication history for glucocorticoid use 2, 3

Remember that early detection based on clinical suspicion is crucial to prevent mortality from adrenal crisis, as it remains a significant cause of death in patients with adrenal insufficiency 5.