Congenital adrenal hyperplasia medical therapy
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Congenital adrenal hyperplasia main page |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor-In-Chief: Cafer Zorkun, M.D., Ph.D. [2]
Overview
Medical Therapy
Neonatal management
Prenatal diagnosis
- Virilization of female fetuses begins early so early diagnosis and treatment are required.
- Maternal administration of dexamethasone which crosses the placenta into the fetal circulation.
- If treatment cannot be started by 9 weeks, it should not be given at all. 10
- Treatment should be discontinued if male fetus which can be determined by cell-free fetal DNA [12]
- 85% of managed cases appear quite normal after delivery. 13
- Side effects of prenatal dexa
- Postnatal failure to thrive
- Psychomotor developmental delay.[15].
- No effect on IQ [18].
- Increased risk of cleft lip and palate [19].
- Increased risk for psychiatric disturbances and ADHD.[20].
Neonatal treatment
- Hydrocortisone is 20 to 30 mg/m2/day
- Fludrocortisone 100 mcg one gram or 4 mEq/kg/day of sodium chloride
- Growth suppression occur in neonates treated with high doses of hydrocortisone.[2]
Ambiguous genitalia
- Initial evaluation is pelvic ultrasonography to evaluate internal genitalia, karyotype for sex chromosome (SRY probe) material, measurement of 17-hydroxyprogesterone and serum electrolytes. Until results release, glucocorticoid, mineralocorticoid and sodium chloride should be initiated
- Girls with classic CAH typically undergo reconstructive surgery, usually clitoroplasty and vaginoplasty [26-28]
Adrenal crisis
- 20 mL/kg of normal saline should be administered.
- An intravenous bolus of 2 to 4 mL/kg of 10 percent dextrose should be considered if there is significant hypoglycemia.
- Hyperkalemia should be corrected with the administration of glucose and insulin if necessary.
Acute Pharmacotherapies
21-Hydroxylase
- Treatment is aimed at decreasing the drive to produce ACTH (AdrenoCorticoTropic Hormone), thereby decreasing androgen secretion. Glucocorticoids are given usually as hydrocortisone 25 mg QD in divided doses. The dose of steroids must be carefully titrated so that androgen production is minimized, but growth inhibition and Cushing’s syndrome from glucocorticoid excess is avoided. Assessing bone age and growth rate, signs of androgen excess and menstrual cycling gauge response to therapy. Adjunctive therapy with flutamide, an anti-androgen and testolactone, and anti-aromatase, have been shown to minimize the effects of excess androgens, reduce the dose of glucocorticoids and normalize growth rates.
- Mineralocorticoids, with or without evidence of evidence of salt loss, should be given in the form of fludrocortisone. It decreases excessive renin and Angiotensin II (AII) production. AII stimulates early steps in the steroidogenic pathway and leads to more androgen production. Both renin and AII are elevated in the salt-wasting and virilizing forms of CAH. The usual adult dose is 0.1 mg/day.
11-Hydroxylase
Treatment is similar to 21-hydroxylase deficiency with glucocorticoid replacement. Clinical assessment of virilization, growth velocity, hair growth, menstrual function and blood pressure are necessary. Despite adequate glucocorticoid replacement, medication may be required to control blood pressure. Spironolactone is a good choice as well as calcium blockers.