Congenital Adrenal Hypoplasia
Congenital adrenal hypoplasia is a rare disorder, which is characterised by the reduced secretion of hormones from the adrenal glands. Primarily affecting males in infancy, this condition disrupts many biological processes of the body and can lead to adrenal insufficiency and hypogonadotropic hypogonadism (HH), which involves low levels of sex hormones.
The adrenal glands are located above each kidney and produce important hormones such as cortisol and aldosterone, which control essential body functions such as maintaining water balance, regulating metabolism of proteins and fats, blood sugar, blood pressure, and aid in recovery from injury or disease. Androgens (sex hormone) and adrenaline are also produced in small quantities.
Congenital adrenal hypoplasia is a genetic disease caused by a defective gene, which causes defects in certain receptors of the adrenal gland.
Patients with congenital adrenal hypoplasia would require regular monitoring of hormone levels and long-term management of the condition. You will have to be careful to avoid physiologic stress in the form of trauma and surgery. Wearing an identifier, such as a bracelet or anklet, can help medical personnel identify your condition in times of emergency and take the necessary precautions.
Congenital adrenal hypoplasia presents in newborns, however, symptoms are gradual in onset and the symptoms may present later in childhood. Adrenal insufficiency is characterised by vomiting, difficulty feeding, dehydration, very low blood glucose levels and shock. Hypogonadotropic hypogonadism or low levels of sex hormones can cause delayed puberty, micro penis, hypospadias (opening of the penis on the underside rather than the tip), underdeveloped reproductive tissues, undescended testicles and infertility. Other symptoms may include:
Intrauterine growth retardation
Hyperpigmentation (darkening of skin in certain areas)
Loss of hearing
The disease progresses slowly until there is a stressful event such as an accident or injury, which causes the symptoms to become more acute.
Once congenital adrenal hypoplasia is suspected, a diagnosis is made by performing:
- Biochemical tests to determine the levels of electrolytes, glucose and adrenal hormones
- Imaging studies such as CT scan and abdominal ultrasound may also help in establishing the cause of the condition
- Genetic studies to look for any genetic abnormality
Untreated congenital adrenal hypoplasia can cause life-threating complications and even death as your body is unable to maintain normal blood pressure and metabolism when a stressful condition such as an injury or disease occurs.
Treatment involves lifelong replacement or substitution of hormones that are inadequately produced by the adrenal glands, and oral sodium chloride supplements in young children. During a period of stress or illness, your dose of steroid replacement is increased.
In case of an emergency, you are closely monitored for dehydration, blood pressure, and levels of glucose and electrolytes and intravenous injection of hydrocortisone, saline and glucose are administered to facilitate rapid improvement.
Associated hypogonadotropic hypogonadism is managed by increasing doses of testosterone to initiate puberty.
The adrenal gland produces hormones that are vital to life. Congenital adrenal hypoplasia usually requires long-term steroid and hormone replacement therapy. This condition can be life threatening unless it is promptly treated.
Extensive research has been done on congenital adrenal hypoplasia. Various studies include:
Yu T, Wang J, Yu Y, et al. X-linked adrenal hypoplasia congenita and hypogonadotropic hypogonadism: Identification and in vitro study of a novel small indel in the NR0B1 gene. Mol Med Rep. 2016 May;13(5):4039-45.
Karsli T, Sutter J, Shekhawat PS. X-linked Adrenal Hypoplasia Congenita Due to NR0B1 (DAX1) Deficiency Presenting as Severe Respiratory Distress in Near Term Infants. Pediatr Neonatol. 2016 Feb 24.
Battaglia A, Carey JC, South ST. Wolf-Hirschhorn Syndrome. 2002 Apr 29 [Updated 2015 Aug 20]. In: Pagon RA, Adam MP, Ardinger HH, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2016.