## Clinical Context: Acute Illness in Known Addison Disease This patient has **acute adrenal crisis triggered by infection (upper respiratory tract infection) in a patient with pre-existing primary adrenal insufficiency**. The acute GI symptoms, hypotension relative to baseline, tachycardia, and electrolyte derangement indicate decompensation. **Key Point:** Patients with Addison disease require **stress-dose glucocorticoid coverage** during acute illness, surgery, or trauma. Failure to escalate steroids during physiological stress is a common cause of preventable adrenal crisis. ## Stress Dosing in Addison Disease | Clinical Scenario | Glucocorticoid Dose | Duration | |---|---|---| | Minor illness (fever, mild infection) | Double home dose orally | 3–5 days | | Moderate illness (significant infection, dehydration) | 25–50 mg IV/IM hydrocortisone, then 25 mg q6h | Until acute phase resolves | | Major illness/surgery/trauma | 50–100 mg IV hydrocortisone stat, then 50–100 mg q6h or continuous infusion | 24–48 hours, then taper | | **This case** | **50 mg IV stat, then 25 mg q6h** | **Until stabilized** | **High-Yield:** Stress dosing is **empiric and does not require waiting for ACTH or cortisol results**. The clinical context (known Addison disease + acute illness + hemodynamic change) is sufficient to justify immediate escalation. ## Management Flowchart ```mermaid flowchart TD A[Known Addison disease + acute illness]:::outcome --> B{Hemodynamic instability<br/>or severe symptoms?}:::decision B -->|Yes| C[IV hydrocortisone 50 mg stat]:::urgent C --> D[Repeat 25 mg IV q6h]:::action D --> E[IV fluid resuscitation<br/>Normal saline]:::action E --> F[Treat underlying cause<br/>e.g., antibiotics for infection]:::action F --> G[Monitor vitals, electrolytes]:::action G --> H[Taper steroids as acute<br/>phase resolves]:::action B -->|No| I[Double home dose orally<br/>+ supportive care]:::action ``` ## Why This Approach? 1. **Hydrocortisone is the agent of choice:** It has both glucocorticoid and mineralocorticoid activity; IV formulation is rapid-acting. 2. **Dosing rationale:** 50 mg IV stat covers the acute crisis; 25 mg every 6 hours (total 100 mg/day) is standard stress dosing for moderate-to-severe illness. This is ~10–20 times the maintenance dose. 3. **Concurrent IV fluids:** Normal saline (0.9%) restores intravascular volume and corrects mild hyponatremia. 4. **Treat the trigger:** Identify and treat the underlying infection (in this case, likely viral upper respiratory tract infection, but bacterial superinfection must be excluded). **Clinical Pearl:** Patients with Addison disease should carry a **medical alert card or bracelet** and be educated to increase their steroid dose during intercurrent illness or to seek emergency care. Some are given emergency IM hydrocortisone kits for self-administration. ## Common Pitfalls **Warning:** Do not: - Continue home-dose steroids during acute illness (insufficient coverage). - Delay IV steroids while awaiting imaging or test results. - Use dexamethasone as first-line (it lacks mineralocorticoid activity and has a longer half-life, making titration difficult in acute crisis). 
Sign up free to access AI-powered MCQ practice with detailed explanations and adaptive learning.