What Is Pediatric Growth Hormone Deficiency?

Pediatric growth hormone deficiency occurs when the pituitary gland does not make enough growth hormone, which stimulates growth of bone and other tissues. The pituitary gland, a small, bean-shaped gland located near the base of the brain and attached to the hypothalamus, affects almost every body system. When the pituitary gland or hypothalamus, which helps regulate the pituitary gland, is damaged or malformed, a growth hormone deficiency can result. Injury to either organ can be congenital or acquired. Pediatric growth hormone deficiency occurs in about 1 in every 4,000 to 10,000 people in the United States. 

Types of Growth Hormone Deficiencies 

Pediatric growth hormone deficiency is classified based on its cause:

• A congenital deficiency refers to an abnormal formation of the pituitary gland or hypothalamus that was present at birth.
• An acquired deficiency describes the damage to the pituitary gland or hypothalamus that occurred in a child during or after birth. 

Pediatric Growth Hormone Deficiency Symptoms

In those with pediatric growth hormone deficiency, the pituitary gland is unable to produce a sufficient amount of growth hormone. This leads to the main symptom, slow height growth. Growth rates vary considerably from child to child. Average growth is often described as:

• 0–12 months: About 10 inches a year
• 1–2 years: About 5 inches a year
• 2–3 years: About 3 ½ inches a year
• 3 years to puberty: About 2 to 2 and a half inches a year

If your child is less than the third percentile in height for a child of their age, that can be a sign that they have growth hormone deficiency. Short stature in children is the most common reason for a referral to a pediatric endocrinologist.

A child with a growth hormone deficiency also appears younger and has a childlike face. Their body will usually appear chubbier than is typical for their age. Children with growth hormone deficiency may also experience delayed puberty and less body hair than their peers. They may also have a more prominent forehead and underdeveloped bridge of the nose. While children with this condition appear younger physically, they continue to develop mentally and emotionally and do not usually have any cognitive impairment. 

Causes

Pediatric growth hormone deficiency is caused by a damaged or malformed pituitary gland or hypothalamus. Congenital growth hormone deficiency can occur if there are mutations in genes for factors that are important in pituitary gland development or in receptors and factors along the growth hormone pathway. However, the cause of most of these cases remains unknown.

Physical malformations of the skull or face can lead to a malformed pituitary gland and resulting growth hormone deficiency. Examples include cleft lip or cleft palate.

Acquired growth hormone deficiency can be caused by:

• A brain tumor in the hypothalamus or pituitary gland
• Head trauma
• Radiation therapy for cancer, if the treatment field includes the hypothalamus and pituitary
• Diseases that infiltrate the hypothalamus or its connection to the pituitary gland, such as histiocytosis (an abnormal increase in the number of immune cells called histiocytes)
• An autoimmune condition, such as lymphocytic hypophysitis

Diagnosis

Your child’s pediatrician will first have to rule out other causes contributing to slowed growth. They will most likely start by closely monitoring your child's height over time. When pediatric growth hormone deficiency is strongly suspected, your child will be referred to a pediatric endocrinologist for further evaluation and treatment. 

Diagnostic tools for pediatric growth hormone deficiency include:

• A hand X-ray can reveal your child’s bone age. If the X-ray shows that the hand bones appear younger than the child’s age, this could be a sign of pediatric growth hormone deficiency.
• Lab tests measuring insulin-like growth factor 1 (IGF-1) and insulin-like growth factor-binding protein 3 (IGFBP3) can also aid in making the diagnosis. Growth hormone stimulates the production of both of these growth factors, so if their levels are low, it may be a sign of growth hormone deficiency. 
• Provocative growth hormone testing measures the ability of the body to produce growth hormone. Medications are given during this test to stimulate the pituitary gland to release growth hormone. If the level is low, it confirms the diagnosis of growth hormone deficiency.
• An MRI scan of the head can reveal malformations of the pituitary gland or hypothalamus.

These tests may be repeated after treatment and into adulthood to monitor your child’s progress. 

Treatment

The typical treatment for pediatric growth hormone deficiency is regular injections of human growth hormone. The injections may need to be done daily. While treatment with hormone replacement may take years, the growth rate usually improves in a matter of months. Most pediatric endocrinologists begin with a low dose and slowly titrate up as the child tolerates the injections better. 

The goal of growth hormone therapy is to help a child reach their full potential adult height. When growth hormone injections are successful, children usually grow an average of 4 or more inches in the first year of therapy and 3 or more inches in the following two years. This treatment needs to be closely followed by both a pediatric endocrinologist and a pediatrician. 

However, it should be noted that not all children respond to hormone therapy. Hormone therapy also comes with side effects, including:

• Fluid retention 
• Headaches 
• Muscle aches 
• Slippage of hip bones 

Prognosis

The prognosis for pediatric growth hormone deficiency depends on several factors, including the underlying cause, the extent of the slowed growth, and the age at which the condition is diagnosed.

As a general rule of thumb, the earlier treatment begins, the more successful it is. When treatment with growth hormone injections starts in early childhood, there is a greater likelihood of the child attaining a “normal” adult height.

A child’s prognosis has also been linked to their race and ethnicity. A 2018 study found health disparity in the treatment of pediatric growth hormone deficiency. White children appeared to be diagnosed earlier and treated with hormone therapy more often than Black children. This inequity is unacceptable and crucial for pediatricians and pediatric endocrinologists to know. 

Coping

Having a short stature and the other symptoms of pediatric growth hormone deficiency can significantly impact a child and their family. Research has shown that children who are shorter and appear younger than their peers are at higher risk of experiencing bullying. Shorter children are also more likely to exhibit behavioral disturbances at home and at school. 

Children undergoing treatment for growth hormone deficiency and their parents experience anxiety about their height and the effectiveness of treatment. A 2013 study found that 92% of parents with children undergoing hormone therapy for short stature worried about their children’s height. It also found that of the children not undergoing treatment, 97% of their parents frequently worried about their height. 

Children who are shorter than their peers may have poor self-esteem or depression. It’s important to talk about these problems with your child and your child's healthcare provider. They can recommend counseling or support groups for you and your child.

A Word From Verywell

Finding out that your child has a chronic health condition is distressing for any parent. Pediatric growth hormone deficiency may be present when your child is born or may come on later due to an injury or health condition. Thankfully, there is treatment available for this condition, which usually involves injections of human growth hormone, as well as mental health therapy to help you and your child cope with the issues that come with this condition. It’s helpful to remember that the sooner treatment is initiated, the more effective it usually is. By identifying the condition as soon as possible, you can still help your child grow into a normal height and live a healthy life.