Growth Hormone treatment, [somatropin (rDNA origin) injection, often referred to as GH, is recommended for girls with Turner Syndrome and requires daily injections of growth hormone once the child drops below the 5th percentile in height. Injections are given subcutaneously at night in attempt to mimic the natural secretion of growth hormone, which peaks at night. Most pediatric endocrinologists monitor growth and adjust dose every 3–6 months. Treatment is usually extended if the child is growing. A child usually takes growth hormone until their growth velocity has decreased to 2 cm (~.79 inches) over the previous year with a bone age of at least 13-14 years. Bone age does not necessarily match actual age, therefore it is possible to take growth hormone beyond 14 years of age.
GH treatment is expensive, costing as much as $10,000 to $60,000 a year in the United States. Treatment for Turner Syndrome is considered medically necessary and is covered by most insurance companies. Industry does provide support to those in need. If you are un-insured or unable to afford treatment, a treating physician should provide necessary support to appeal for insurance coverage; clinical guidelines for TS indicate that GH is a critical treatment for TS. Assistance is available for those who may need it.
Short stature affects at least 95% of all individuals with TS and is the most consistent and readily recognizable clinical feature of TS. Short stature in TS is characterized by mild intrauterine growth restriction, slow growth during infancy, delayed onset of the childhood component of growth, and growth failure during childhood and adolescence without a pubertal growth spurt. This growth failure leads to a reduced final height, which is approximately 20 cm (~ 7.9 inches) below the female average of the corresponding ethnic group. The average height left untreated is 4’7″.
Final adult height for patients treated by growth hormone are greater in patients who:
- Initiate treatment at a young age
- Are relatively tall at start of treatment
- Are short in relation to their parents
- Are treated with high doses of GH
- Other factors affecting final adult height include:
- Familial genetics
- General health
- Specific genetic components
Growth hormone treatment is effective in most girls when started early in life. Growth hormone initiated around 4–6 years of age, and preferably before 12–13 years when:
- The child already has evidence of growth failure (e.g., below 50th percentile height velocity (HV) observed over 6 months in the absence of other treatable cause of poor growth
- The child is already short or has a strong likelihood of short stature e.g., short parents and short predicted adult height or already pubertal at the time of diagnosis.
The Toddler Study indicates an even more notable growth when treatment is initiated very early in life during the toddler years.
GH treatment consists of daily injections given subcutaneously at night in attempt to mimic the natural secretion of growth hormone. If you were to miss an injection, skip the dose you missed and take the next dose the following day as prescribed. Do not take any extra doses because you have missed one. Furthermore, it is still necessary to take the injections if you are traveling or away from home. Failure to adhere to treatment as prescribed leads to significant reduction of growth hormone treatment efficacy. Always seek the advise of your doctor, case manager, or nurse hotline to answer specific questions or concerns.
Although rare in children, there is the possibility of salt and fluid retention which may lead to the swelling of lower limbs, hands, or wrists (especially during first days/weeks of treatment). Slipped Capital Femoral Epiphyses (SCFE) may also occur. This is the displacement of the growth plate at the femur, which can possibly lead to hip or knee pain. Another side effect to GH treatment is headaches, which may be caused by an increase in the pressure on the brain. If headaches do occur, the medication can be stopped for a short time, the headaches should subside, and the medication can then be restarted.
While taking GH, some changes that may occur in your child include: increased weight, increased muscle and bone mass, increased strength, increased balance and coordination, increased metabolism and appetite, and improvement in mood.
How should I discuss this with my child/family?
When talking about the treatment with your child, always remain calm and patient; yet firm. Explain to your child that this is medicine that must be given to help them grow. For any questions, concerns, or comments you may have, talk with your doctor or case manager. If you can’t do the injections alone, having a support system (friends, neighbors, etc.) is helpful. Ensuring your child has a nighttime routine can also help to make things run more smoothly. To get your family involved in this new process, have them measure their own heights every so often with your child that is taking growth hormone so she can realize she is growing just like your family.