What is the primary cause and treatment of Congenital Adrenal Hyperplasia (CAH)?

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From the Guidelines

Congenital Adrenal Hyperplasia (CAH) is primarily caused by genetic mutations that affect enzymes involved in cortisol production, with 21-hydroxylase deficiency accounting for over 90% of cases. The standard treatment for CAH involves lifelong glucocorticoid replacement therapy, typically with hydrocortisone at doses of 10-15 mg/m² per day divided into 2-3 doses 1. For salt-wasting forms of CAH, mineralocorticoid replacement with fludrocortisone (0.05-0.2 mg daily) is also necessary, along with sodium supplementation (1-2 g daily) especially in infants. Treatment aims to replace deficient hormones while suppressing excess androgen production that causes virilization and growth problems.

Key Considerations

  • Dosing must be carefully individualized based on clinical response, growth parameters, and hormone levels 1.
  • Stress dosing (typically tripling the usual dose) during illness, surgery, or significant physical stress is crucial to prevent adrenal crisis.
  • Regular monitoring of growth, bone age, blood pressure, and hormone levels is essential for optimal management.
  • Early diagnosis and consistent treatment help prevent life-threatening adrenal crises and minimize the long-term complications of the condition.

Management Principles

  • Patients with CAH require lifelong steroid replacement, both glucocorticoids and mineralocorticoids, and often an increased intake of sodium chloride to compensate for increased renal loss 1.
  • Education on how to increase steroid doses during concurrent illnesses or injury is important, as well as training in intramuscular administration of HC during acute adrenal crisis.
  • Patients should wear a Medic Alert Bracelet and carry a steroid card to inform medical personnel on chronic CAH status.

From the Research

Cause of Congenital Adrenal Hyperplasia (CAH)

  • CAH is a group of autosomal recessive disorders of adrenal steroidogenesis caused by a genetic disorder in one of the steroidogenic enzymes 2.
  • The primary cause of CAH is a deficiency in one of the enzymes involved in cortisol synthesis, with 21-hydroxylase deficiency being the most common form, accounting for about 90% of all cases 2, 3.
  • 21-hydroxylase deficiency is caused by mutations in the CYP21A2 gene, which encodes the 21-hydroxylase enzyme 3, 4.
  • Other rare types of CAH include 11β-hydroxylase and 3β-hydroxysteroid dehydrogenase deficiency 2, 5.

Treatment of Congenital Adrenal Hyperplasia (CAH)

  • The treatment of classical CAH involves replacing both glucocorticoid (GC) and mineralocorticoid hormones to prevent salt wasting crisis and reduce excessive corticotropin 6.
  • Glucocorticoid therapy is recommended in children with inappropriately early onset and rapidly progressing pubarche or accelerated bone age progression, and in adolescents with non-classical CAH (NCCAH) who have overt virilization 6.
  • Hydrocortisone is used for glucocorticoid replacement, along with increased stress doses for acute illness, trauma, and procedures 6, 5.
  • Mineralocorticoid and salt replacement may also be necessary in some cases 5.

References

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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