Diagnosis and management of congenital adrenal hyperplasia: clinical, molecular and prenatal aspects.

Congenital adrenal hyperplasia (CAH) is the most common cause of female pseudohermaphroditism in Indian children. It is caused by enzymatic defects in the steroidogenic pathway of the adrenal glands and is characterized by impaired cortisol and aldosterone synthesis and overproduction of androgens. The disease usually presents with life-threatening problems and virilization, with long term physical and psychological effects. The clinical and laboratory diagnoses play an important role in deciding the course of treatment, which continues lifelong. To ensure proper growth and development of the patient, optimized disease management and treatment with steroids is required. Often the patient also requires surgical correction. Recent developments in molecular genetics have greatly helped in understanding the pathogenesis of the disease. The gene encoding for steroid 21-hydroxylase, CYP21, is located on the short arm of chromosome 6 in the HLA region and is amplified for genetic diagnosis. Rapid characterization of point mutations is possible using the allele-specific polymerase chain reaction technique in affected children. Counselling, prenatal diagnosis and treatment are recommended in all pregnant women with a positive family history to reduce or eliminate the effects in affected foetuses. This spares the female newborn the consequences of genital ambiguity and problems of gender identity.