Criteria for Suspecting Adrenal Insufficiency in an Inpatient Setting
Adrenal insufficiency should be suspected in hospitalized patients presenting with hypotension, fever, unexplained fatigue, nausea/vomiting, hyponatremia, or hyperkalemia, particularly in those with risk factors such as chronic steroid use, critical illness, or known endocrine disorders. 1
Clinical Presentation
The following clinical features should prompt consideration of adrenal insufficiency:
Vital Signs and General Appearance
- Hypotension (especially refractory to fluid resuscitation)
- Fever, chills, sweats, or hypothermia 1
- Altered mental status
- Unexplained shock
Common Symptoms
- Fatigue (present in 50-95% of cases) 2
- Nausea and vomiting (20-62%) 2
- Anorexia and weight loss (43-73%) 2
- Abdominal pain
Laboratory Abnormalities
- Hyponatremia
- Hyperkalemia (particularly in primary adrenal insufficiency)
- Hypoglycemia
- Eosinophilia
- Hypercalcemia
Risk Factors
Particular attention should be paid to patients with:
- Recent interruption of glucocorticoid therapy 1
- History of chronic steroid use
- Comorbidities such as asthma and diabetes 1
- Known primary adrenal insufficiency on inadequate replacement 1
- Critical illness or severe physiological stress
- Liver disease, especially hepatitis C and prior liver transplantation 3
- HIV infection 3
- Male hypogonadism 3
Diagnostic Approach
Initial Laboratory Testing
- Early morning (8 am) serum cortisol measurement:
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 |
| [1] |
Additional Testing
- ACTH stimulation test (cosyntropin 250 μg) when diagnosis is uncertain
- Peak cortisol <18 μg/dL at 30 or 60 minutes indicates adrenal insufficiency 2
- In hypoproteinemic patients (albumin ≤2.5 g/dL), total cortisol levels may be falsely low 5, 6
- Consider free cortisol measurement or calculation when available
- A random free cortisol ≥1.8 μg/dL generally excludes adrenal insufficiency 5
Important Caveats
- Do not delay treatment in suspected adrenal crisis while awaiting laboratory confirmation 1
- Normal cortisol levels should not rule out adrenal insufficiency in a patient with a suggestive clinical presentation 1
- Hypoalbuminemia can lead to falsely low total cortisol levels 5, 6
- The cortisol increment after ACTH stimulation should not be used as the sole criterion for defining adrenal function in critically ill patients 5
- Commonly reported clinical features of adrenal insufficiency may overlap with other conditions in hospitalized patients 3
Management Considerations
If adrenal insufficiency is suspected:
- For suspected adrenal crisis: Immediate hydrocortisone 100 mg IV, followed by continuous infusion of 200 mg/24h until stabilized 1, 7
- Fluid resuscitation with normal saline (10-20 ml/kg; maximum 1,000 ml) 1
- Once stabilized, transition to oral glucocorticoid at double the pre-event therapeutic dose for 48 hours 1
- Add mineralocorticoid replacement (fludrocortisone) once enteral feeding is established, particularly for primary adrenal insufficiency 1
Remember that early recognition and prompt treatment of adrenal insufficiency can be lifesaving, particularly in critically ill patients.