CAH Treatment Guidelines
Growing children with classic CAH should be treated with hydrocortisone tablets 10-15 mg/m²/day divided three times daily, combined with fludrocortisone 0.05-0.2 mg/day and sodium chloride supplements 1-2 g/day in infancy. 1
Glucocorticoid Replacement
Growing Children (Preferred Regimen)
- Hydrocortisone tablets: 10-15 mg/m²/day divided into 3 daily doses 1
- Avoid oral HC suspension and chronic use of long-acting glucocorticoids (prednisolone, dexamethasone) in growing patients 1
- The short half-life of hydrocortisone minimizes growth suppression compared to longer-acting agents 1
Critical pitfall: Attempting to completely normalize 17-OHP levels typically results in overtreatment with growth suppression, hypertension, and iatrogenic Cushing's syndrome 1. Accept moderately elevated 17-OHP levels to avoid glucocorticoid excess.
Fully Grown Adults (Options Available)
Once growth is complete, longer-acting glucocorticoids become acceptable alternatives 1:
- Hydrocortisone: 15-25 mg/day in 2-3 doses
- Prednisone: 5-7.5 mg/day in 2 doses
- Prednisolone: 4-6 mg/day in 2 doses
- Dexamethasone: 0.25-0.5 mg/day in 1 dose
While dexamethasone provides superior adrenal suppression, it carries the highest risk of adverse effects including lowest bone mineral density and highest BMI 2. Hydrocortisone or prednisolone are safer choices when growth is complete.
Mineralocorticoid Replacement
All patients with classic CAH require fludrocortisone 0.05-0.2 mg/day (1-2 times daily) plus sodium chloride supplements 1-2 g/day (17-34 mEq/day) in infancy, divided among feedings 1
- Reassess the need for mineralocorticoid therapy periodically, as some patients recover from salt-wasting over time 1
- Monitor blood pressure closely, especially in infants receiving high-dose fludrocortisone due to immature renal tubular sodium reabsorption 1
Stress Dosing
Increase glucocorticoid doses for:
- Febrile illness ≥38.5°C
- Gastroenteritis with dehydration
- Surgery with general anesthesia
- Major trauma 1
Recommended stress doses (parenteral hydrocortisone): 1
- Infants/preschool children: 25 mg
- School-age children: 50 mg
When pharmacological HC doses are given during stress, mineralocorticoids are unnecessary as HC activates mineralocorticoid receptors 1.
Do NOT increase doses for:
- Mental/emotional stress
- Minor illness
- Physical exercise 1
Critical caveat: Patients with nonclassic CAH do not require stress dosing unless adrenal function is suboptimal or iatrogenically suppressed 1.
Monitoring Parameters
Hormonal Monitoring
- Use consistently timed hormone measurements 1
- Do not completely suppress endogenous adrenal steroid secretion to avoid overtreatment 1
- Monitor 17-OHP, androstenedione, testosterone levels
- Check plasma renin activity and aldosterone-to-PRA ratio to assess mineralocorticoid adequacy 1
Clinical Monitoring
- Growth rate and height velocity
- Body weight and BMI
- Blood pressure (particularly important with mineralocorticoid therapy)
- Bone age advancement
- Signs of glucocorticoid excess (growth suppression, weight gain, hypertension)
- Signs of inadequate androgen suppression (virilization, accelerated bone age) 1
Frequency
- Frequent reassessment needed in infancy when rapidly reducing initially high doses 1
- Regular monitoring throughout childhood to balance the competing risks of undertreatment (adrenal crisis, androgen excess, growth potential loss) versus overtreatment (growth suppression, Cushing's syndrome) 1
Practical Considerations
All patients should wear or carry medical identification indicating adrenal insufficiency 1
During acute illness, avoid fasting and provide glucose and electrolyte supplementation to young children due to hypoglycemia and electrolyte imbalance risk 1.
Recent data suggests that while three-times-daily hydrocortisone is the guideline recommendation, real-world practice shows equivalent growth outcomes with various regimens including twice-daily dosing or prednisolone 3. However, the Endocrine Society guidelines remain the standard of care prioritizing hydrocortisone three times daily in growing children to minimize growth suppression 1.