The adrenal glands are an important part of the endocrine system; they make hormones that affect the rest of the body. Adrenal hypoplasia is a disorder in which the adrenal glands do not develop properly, causing them to make low levels of hormones necessary for the regulation of metabolism and water balance in the body.
Congenital Adrenal Hypoplasia
Adrenal hypoplasia is the result of a genetic mutation that causes the adrenal glands to develop improperly. This condition, according to Gene Reviews, is called congenital adrenal hypoplasia or X-linked adrenal hypoplasia congenita. Because adrenal hypoplasia is a result of genetic abnormalities, it is often hereditary, even if neither of the patient's parents have this disease.
Symptoms
The main symptoms of adrenal hypoplasia are those of adrenal insufficiency, the Genetics Home Reference explains. Consequently, patients may have very low blood sugar and blood pressure, which can lead to shock. Patients may also have a craving for salt, nausea and vomiting as well as dehydration. Gene Reviews notes that 60 percent of patients with this disorder develop symptoms within a few weeks of life, whereas the remaining patients manifest symptoms during childhood. Males that have this disorder may also have a lack of testosterone, which can lead to underdeveloped genitalia, testicles that do not descend, infertility and delayed puberty.
Inheritance
Most cases of congenital adrenal hypoplasia are X-linked, which means that they are more likely to affect males (because males only have one X chromosome). The condition, according to the Genetics Home Reference, is caused by NR0B1 gene, which makes a protein called DAX1. DAX1 is important for the proper development of the adrenal glands. X-linked diseases in males are inherited from the mother, who may have no signs of the disease if only one of her X chromosomes contains the genetic mutation.
Diagnosis
Primary adrenal insufficiency that occurs in the first month of a patient's life strongly suggests adrenal hypoplasia, particularly if the patient is a male. Primary adrenal insufficiency can be diagnosed by measuring the levels of certain adrenal hormones in the patient's blood, including cortisol and aldosterone as well as a pituitary hormone (called ACTH) that stimulates adrenal hormone production. Low cortisol and aldosterone levels coupled with high ACTH levels is indicative of primary adrenal insufficiency. Genetic testing of the patient can be used to confirm the diagnosis of congenital adrenal hypoplasia.
Treatment
The treatment of adrenal hypoplasia, according to Gene Reviews, is replacement of the under-produced adrenal hormones. Cortisol, for example, can be replaced with the synthetic corticosteroids prednisone or dexamethasone. Patients will need regular testing from an endocrinologist to ensure that their dosage is appropriate and may need additional hormones during an illness or stress.
