Background
Adrenocorticotropic hormone (ACTH) deficiency due to any cause and defects in the ACTH receptor result in hypoplasia of the adrenal cortex. However, this article focuses on primary disorders of adrenal gland formation (ie, primary adrenal hypoplasia).
Four forms of congenital adrenal hypoplasia have been identified, as follows:
An X-linked form (OMIM 300200) is caused by a mutation or deletion of the DAX1 gene (dosage-sensitive sex reversal adrenal hypoplasia congenita critical region of the X chromosome, also called the NR0B1 gene) on the X chromosome.
This form is usually associated with hypogonadotropic hypogonadism.
It may be part of a contiguous chromosome deletion, which may include congenital adrenal hypoplasia, Duchenne muscular dystrophy (OMIM 310200), and glycerol kinase deficiency (OMIM 307030).
The autosomal recessive form is due to a mutation or deletion of the gene that codes for steroidogenic factor 1 (SF-1) on chromosome 9q33 (OMIM 184757).
This form is also associated with hypogonadotropic hypogonadism.
An autosomal recessive form of uncertain etiology (OMIM 240200) has also been identified.
A form of adrenal hypoplasia associated with intrauterine growth retardation, metaphysial dysplasia, and genital abnormalities has been identified (ie, intrauterine growth retardation, metaphyseal dysplasia, adrenal hypoplasia congenita, genital anomalies [IMAGe] association; OMIM 300290).