Growth Hormone Deficiency
Growth hormone is a special type of protein made in the brain by the pituitary gland. It is responsible for more than just physical growth – it helps our muscles, bones and metabolism. Growth hormone deficiency (GHD) can occur at any age, in both children and adults. In the United States, approximately one in 4,000 to 10,000 children has GHD, and approximately 50,000 adults have GHD, with about 6,000 new adult patients diagnosed every year.
As the name implies, GHD results when the pituitary gland does not produce enough growth hormone. In children, GHD may occur during infancy or later in childhood and result in a lack of growth. The GHD may be partial, when the pituitary gland doesn’t produce enough growth hormone, or total, when the pituitary gland produces no growth hormone. Most adults are diagnosed with GHD as children and require treatment throughout life; however, it is possible for an adult to acquire GHD later in life, usually through damage to the pituitary or hypothalamus gland.
What Causes GHD?
The cause of GHD in children and adults is a poorly formed or damaged pituitary gland or hypothalamus. Damage to the pituitary gland or hypothalamus may be the result of an abnormal formation that occurred before birth (congenital) or after birth (acquired). The cause of most cases of congenital GHD is unknown; however, mutations can occur in genes that are important in pituitary gland development, leading to GHD. Acquired cases of GHD include brain tumors in the hypothalamus or pituitary gland, head trauma, radiation therapy for cancers in the hypothalamus and pituitary gland, diseases that affect the hypothalamus or its connection to the pituitary gland, or an autoimmune condition (lymphocytic hypophysitis).
GHD in Children
- Slow growth with normal body proportions
- Immature appearance compared to peers
- A chubby body build
- A prominent forehead
- An underdeveloped bridge of the nose
GHD in Adults
- Increased fat, especially around the waist
- Decreased muscle mass
- Thinning bones
- Higher cholesterol, especially LDL (the bad cholesterol)