What is the initial treatment approach for a patient with autoimmune adrenal insufficiency, considering their potential history of other autoimmune diseases?

Initial Treatment of Autoimmune Adrenal Insufficiency

Most patients with autoimmune adrenal insufficiency require dual hormone replacement: hydrocortisone 15-25 mg daily in divided doses for glucocorticoid replacement plus fludrocortisone 50-200 µg daily for mineralocorticoid replacement. 1

Immediate Glucocorticoid Replacement

• Start hydrocortisone 15-25 mg daily in 2-3 divided doses (typically 10 mg upon waking, 5 mg at noon, and 2.5-5 mg in late afternoon, with the last dose at least 6 hours before bedtime) 1, 2
• Alternative regimens include 15+5 mg, 10+10 mg, or 10+5+5 mg depending on individual response 3
• For children, use 6-10 mg/m² of body surface area 1
• Cortisone acetate 18.75-31.25 mg daily (equivalent to 15-25 mg hydrocortisone) is an acceptable alternative 1
• Use the lowest dose compatible with health and sense of well-being 1

Essential Mineralocorticoid Replacement

• Start fludrocortisone 50-200 µg as a single daily dose 1, 4
• Children and younger adults typically require higher doses (up to 500 µg daily may be needed) 3
• Primary adrenal insufficiency requires both glucocorticoid AND mineralocorticoid replacement, unlike secondary adrenal insufficiency which only requires glucocorticoids 3
• Monitor adequacy by assessing for postural hypotension, salt cravings, serum sodium/potassium, and plasma renin activity 1

Critical Patient Education and Safety Measures

• All patients must wear medical alert identification jewelry and carry a steroid emergency card 1, 2
• Provide emergency injectable hydrocortisone 100 mg IM kit with self-injection training 3, 2
• Instruct patients to double or triple their glucocorticoid dose during minor illness with fever, vomiting, or physical stress 3, 2
• Educate on warning signs of adrenal crisis: severe weakness, confusion, abdominal pain, vomiting, profound hypotension 2

Stress Dosing Protocol

• Minor stress (fever, minor illness): Double the usual daily dose for 1-2 days 3
• Moderate stress: Hydrocortisone 50-75 mg daily or prednisone 20 mg daily 3
• Major stress (surgery, severe illness): Hydrocortisone 100 mg IM/IV before procedure, then 100 mg every 6-8 hours until recovery 3, 2

Screening for Associated Autoimmune Conditions

Continuous surveillance for other autoimmune disorders is mandatory because autoimmune adrenal insufficiency patients are at high risk of developing additional autoimmune diseases. 1

Annual Screening Requirements

• Thyroid function tests (TSH, free T4, TPO antibodies) every 12 months—hypothyroidism and thyrotoxicosis are frequently seen 1, 2
• Plasma glucose and HbA1c annually to screen for diabetes mellitus 1
• Complete blood count annually to screen for anemia 1
• Vitamin B12 levels annually due to common autoimmune gastritis 1
• Tissue transglutaminase antibodies and total IgA if frequent or episodic diarrhea occurs (screening for celiac disease) 1
• Counsel women of reproductive age about risk of premature ovarian insufficiency, especially if side-chain cleavage enzyme antibodies are present 1

Critical Pitfalls to Avoid

• Never start thyroid hormone replacement before adequate glucocorticoid replacement in patients with concurrent hypothyroidism—this can precipitate adrenal crisis 3, 2
• Never delay treatment of suspected adrenal crisis for diagnostic procedures—mortality increases with delayed intervention 1, 2, 5
• Do not rely on hyperkalemia to make the diagnosis—it is present in only ~50% of cases 3, 5
• Avoid liquorice and grapefruit juice as they interfere with hydrocortisone metabolism 1, 3
• If essential hypertension develops on fludrocortisone, reduce the dose but do not stop it 1

Follow-Up Monitoring

• Annual visits to assess symptoms, weight, blood pressure, and serum electrolytes 1, 2
• Evaluate for signs of under-replacement (fatigue, weight loss, hypotension, salt craving) or over-replacement (weight gain, hypertension, edema) 1, 2
• Consider morning cortisol day curve (baseline and 2,4,6 hours post-dose) if rapid cortisol disappearance is suspected 1
• Monitor bone mineral density every 3-5 years to assess for complications of glucocorticoid therapy 1