Understanding Growth Disorders

Let Life Happen

Let Life Happen

Understanding Growth Disorders
Understanding Growth Disorders

Let Life Happen

Understanding Growth Disorders

 

A variety of growth disorders prevent people from growing at their expected rate. This may result in a child not gaining their height or weight at the normal rate and an inability to grow strong bones. The most common growth disorders are outlined below.

In general, one of the most common causes of growth disorders is that a child’s body does produce enough growth hormone, or GH. 

Growth hormone has important functions for growth all over the body, including:

  • Sending signals to all parts of the body involved with growth
  • Building muscle
  • Making strong bones
  • Reducing fat and turning it into energy1

Growth hormone is produced by two glands in the human brain: the pituitary gland and the hypothalamus. Damage to these glands by genetic disorders, injury, tumours or infection, can lead to a deficiency in growth hormone and slowed growth. 

Growth Hormone Deficiency (GHD) is a medical condition that results when the body does not produce enough growth hormone. 

GH is produced by the pituitary gland, which is a pea-sized gland located at the base of the brain. Another gland, the hypothalamus, regulates the release of GH from the pituitary. In people with GHD, the pituitary or hypothalamus glands aren’t functioning properly which can prevent growth, weight gain and the development of strong bones. This means the extra amount that is needed for normal growth then needs to be given. 2

Causes

Signs & Symptoms

Children with GHD have a slow or flat rate of growth which may not become apparent until a child is 2 to 3 years old. A child with GHD has normal skeletal proportions and intelligence.4

  • Other symptoms include:
  • Slow increase in bone length
  • Young-looking face
  • Increased fat, particularly around the stomach area
  • In older children, puberty may be delayed or not start at all 5

Treatment Options

Growth hormone (GH) therapy is used to help children with GHD to grow. The goal of GH therapy is to help your child reach their full height potential. Giving GH injections as prescribed may help to restore your child’s normal growth and reach their maximum final adult height. 

GH can be administered at home using different types of devices, including:

  • Automatic automated drug delivery devices, such as easypod®
  • Manual pens and syringes

As with any medication, side effects can happen. Be sure to consult the leaflet in the box that comes with the medicine to understand possible side effects. Talk to your healthcare team if you have any questions or concerns.

Turner Syndrome (TS) is a growth disorder affecting only females. Most girls are naturally born with two of the same sex chromosomes, called X chromosomes. In girls born with TS, one of the two X chromosomes is missing, incomplete or damaged.6

Causes

Turner Syndrome is not connected with environmental factors or any of the common factors generally associated with genetic issues. It occurs when a piece of genetic information is lost during the division of sex cells.7

Signs & Symptoms

The signs and symptoms of Turner Syndrome vary, depending on the age of the individual. Key clinical features of Turner Syndrome include:

  • Short stature
  • Webbed neck, low posterior hairline, misshapen, rotated ears and narrow palate with crowded teeth or broad chest with widely spaced nipples
  • Difficulty with nonverbal, social or psychomotor skills, although girls with Turner Syndrome typically have normal intelligence
  • Pubertal delay and lack of breast development by 14 years of age
  • Women with Turner Syndrome may experience infertility8

Treatment Options

Early diagnosis is important to allow maximum benefit from therapies which can help treat TS. Growth hormone therapy can speed up growth and increase final adult height. Other treatment options can be proposed by doctors in addition to GH therapy in order to further improve development. Please see the Turner Syndrome Society of Canada for more information.9

Chronic kidney disease (CKD) describes kidney malfunction that develops gradually over time (at least three months). As CKD progresses, the kidneys become less able to remove waste and extra water from the body. People with CKD often have poor growth and can be treated by growth hormone (GH).10

Causes

Growth disorders may be due to a number of factors associated with CKD such as problems getting enough energy and minerals from food for growth, abnormalities in the GH production area and bone disease induced by CKD.11

Treatment Options

There are various therapies that can help with CKD. Growth hormone (GH) therapy can increase the body’s rate of growth and improve final height.12

After conception, a fetus develops and grows in its mother’s womb until birth. The number of weeks a baby spends in the womb before being born is referred to as the baby’s gestational age. If a baby is born smaller than normal for his or her gestational age, he or she will be referred to as being small for gestational age (SGA). A baby is considered SGA if he or she has a birth weight or length less than the 3rd percentile.13

Causes

There are several possible reasons why a baby is born SGA. These factors can include genetic syndromes, maternal factors such as infection or substance abuse and demographic considerations such as the mother’s age or race.14

Signs & Symptoms

A baby born with SGA will be smaller than other babies of the same gestational age. By proportion, the baby will probably have thinner arms and legs but should otherwise look healthy. SGA babies have a good possibility of reaching normal adult height if treated early in childhood with growth hormone therapy. 15

Later in life, children born SGA can possibly have some differences compared with other children. These differences can be countered with early growth hormone treatment and include:

  • Low weight 16
  • Short height 17
  • Less muscle and fat 18
  • Reduced appetite 19
  • Slow growth of bones before puberty which can mean weaker bones in later life 20

Treatment Options

If children born SGA have not caught up with their peers by two to four years of age, their healthcare professional will probably suggest that a pediatric endocrinologist carries out a thorough check-up to determine the possible causes of the small size of the child. Growth hormone treatment may be prescribed to help restore normal growth and treatment is most beneficial if given as early as possible.21

1. Growth Hormone Deficiency: A Guide for Parents and Patients.” Child Growth Foundation. 2004. Available online here

2. “Growth hormone deficiency” MedlinePlus. 2014. Available online here.  Last accessed September 2014.

3. Ibid.

4. “Growth hormone deficiency” MedlinePlus. 2014. Available online here. Last accessed September 2014.

5. Ibid.

6. “Turner Syndrome: Diagnosis and Management.” Thomas Morgan MD. Am Fam Physician. 2007 Aug 1;76(3): 405-417. Available online here

7. Ibid.

8. Ibid.

9. Ibid.

10. “Effect of Growth Hormone Treatment on the Adult Height of Children with Chronic Renal Failure.” Dieter Haffner, M.D., Franz Schaefer, M.D., Richard Nissel, M.D., Elke Wühl, M.D., Burkhard Tönshoff, M.D., and Otto Mehls, M.D. for the German Study Group for Growth Hormone Treatment in Chronic Renal Failure. N Engl J Med 2000; 343:923-930.

11. Ibid.

12. ”Recombinant Human Growth Hormone (rhGH) in Patients with Chronic Kidney Disease (CKD):Guidelines for Therapy.” Canadian Association of Pediatric Nephrologists. May 2007.

13. “Small for Gestational Age Introduction.” The Magic Foundation. 2014. Available online here

14. “Small for Gestational Age Introduction.” The Magic Foundation. 2014. Available online here

15. Dahlgren J, Wikland K on behalf of the Swedish Study Group for Growth Hormone treatment. Final height in short children born small for gestational age treated with growth hormone. Pediatr Res. 2005:57:216−222. Available online here. Last accessed June 2014.

16. Sas,T., de Waal,W., Mulder,P., Houdijk,M., Jansen,M., Reeser,M., & Hokken-Koelega,A. Growth hormone treatment in children with short stature born small for gestational age: 5-year results of a randomized, double-blind, dose-response trial. J Clin Endocrinol Metab 84, 3064-3070 (1999).

17. Van Erum,R., Mulier,M., Carels,C., & de Zegher,F. Short stature of prenatal origin: craniofacial growth and dental maturation. Eur. J Orthod 20, 417-425 (1998).

18. Leger,J., Garel,C., Fjellestad-Paulsen,A., Hassan,M., & Czernichow,P. Human growth hormone treatment of short-stature children born small for gestational age: effect on muscle and adipose tissue mass during a 3-year treatment period and after 1 year's withdrawal. J Clin Endocrinol Metab 83, 3512-3516 (1998).

19. Lee,P.A., Chernausek,S.D., Hokken-Koelega,A.C., & Czernichow,P. International Small for Gestational Age Advisory Board consensus development conference statement: management of short children born small for gestational age, April 24-October 1, 2001. Pediatrics 111, 1253-1261 (2003).

20. de Zegher,F., Albertsson-Wikland,K., Wollmann,H.A., Chatelain,P., Chaussain,J.L., Lofstrom,A., Jonsson,B., & Rosenfeld,R.G. Growth hormone treatment of short children born small for gestational age: growth responses with continuous and discontinuous regimens over 6 years. J Clin Endocrinol Metab 85, 2816-2821 (2000).

21. Dahlgren J, Wikland K on behalf of the Swedish Study Group for Growth Hormone treatment. Final height in short children born small for gestational age treated with growth hormone. Pediatr Res. 2005:57:216−222. Available online here. Last accessed June 2014.