- How to Prevent
What Facts Should I Know about Growth Failure in Children?
What Is the Medical Definition of Growth Failure in Children?
Growth failure is a term used to describe a growth rate that is below the appropriate growth velocity (speed) for age. The term growth delay may refer to a situation in which a child is short but appears to be able to grow longer than children usually do, and thus, may not end up short as an adult. Dwarfism is a term that has often been used to describe extreme short stature; however, the term is unflattering and its use is often avoided. Growth hormone deficiency is sometimes called pituitary dwarfism.
Short stature may be a normal expression of a person's genetic potential and, therefore, the growth rate is normal. Short stature may also be a result of a condition that causes growth failure and a growth rate that is slower than normal.
What Would Cause a Child Not to Grow?
A child is considered to be short if he or she has a height below the 3rd or 5th percentile on a growth chart. A low percentage of all children are considered to be short. However, many of these children have normal growth velocities. The children who fall into this group include those with familial short stature or constitutional growth delay. Those with familial short stature are born with genes that determine their short height, and they usually have parents who are short.
What Is Constitutional Growth Delay?
Constitutional growth delay is a term used to describe children who are small for their age but who have a normal growth rate. Of all children with short stature, only a few have a specific treatable medical condition.
How Long Do Growth Spurts Last?
The most rapid phase of growth occurs in the mother's uterus. After birth, the growth rate gradually declines over the first several years of life. At birth, the average length of a newborn is 20 inches; at 1 year, the average height is about 30 inches; at 2 years, the average height is about 35 inches; and at 3 years, the average height is about 38 inches. After 3 years and until puberty, linear growth continues at a relatively constant rate of 2 inches per year.
What Causes Growth Failure in Children?
Normal growth is the result of several factors, such as nutrition, genetics, and hormones. The following are possible causes of growth failure.
- Familial short stature: Children with this condition have parents with short stature. They have a normal growth velocity, and bone age is not delayed. They enter puberty at a normal time and often complete growth with a short adult height.
- Constitutional growth delay: Also called delayed puberty, children with constitutional growth delay have a normal birth weight, and their growth slows usually during the first year of life. From about age 3 to puberty, these children have an adequate growth velocity. Bone age is usually delayed, and puberty is late. Late puberty allows for more prepubertal growth, usually resulting in a normal adult height. Usually, children with constitutional growth delay do not show growth failure but a period of slow growth velocity occurs during the first year of life and just before puberty.
- Malnutrition: Worldwide, malnutrition is probably the most common cause of growth failure and is usually poverty-related. Nutritional deficiencies in developed countries are more often the result of self-restricted diets. Poor weight gain is often more noticeable than short stature.
- Diseases and disorders: Chronic diseases and systemic disorders that involve the nervous, circulatory, or gastrointestinal systems may be a cause of growth failure. Diseases or disorders involving the liver, kidneys, lungs, or connective tissue may also be a cause.
- Psychosocial dwarfism: This is a disorder of short stature or growth failure and/or delayed puberty. This often occurs in association with emotional deprivation and/or child abuse and neglect.
- Syndromes: Growth failure can be a feature of genetic syndromes, such as Turner syndrome and Down syndrome. It can also be a part of other syndromes, such as Noonan syndrome, Russell-Silver syndrome, and Prader-Willi syndrome.
- Endocrine (hormonal): Endocrine causes include thyroid hormone deficiency (hypothyroidism), growth hormone deficiency, or other hormone disorders. Thyroid hormone is necessary for normal growth; in children with hypothyroidism, growth is extremely slow. Children with growth hormone deficiency have normal body proportions, but they may appear younger than their actual age.
- Other: Growth failure may be related to intrauterine growth retardation (a condition in which children weigh less than 5 pounds at full term or who are small for gestational age if born preterm). Bone and cartilage disorders (called chondrodystrophies) may also be a cause of growth failure. Achondroplasia (one of the most common conditions that cause growth failure and short stature) is a genetic disorder of bone and cartilage. People with achondroplasia have a normal-sized trunk, short arms and short legs, and a slightly enlarged head with a prominent forehead. Adults with this condition are typically about 4 feet tall. There are other chondrodystrophies, such as hypochondroplasia, which are similar to achondroplasia but not as severe.
What Are the Symptoms of Growth Failure in Children?
Symptoms of growth failure may include the following:
- The child's height, weight, and head circumference do not progress normally according to standard growth charts.
- Physical skills, such as rolling over, sitting up, standing, or walking, are slow to develop.
- Social and mental skills are delayed.
- The development of secondary sexual characteristics (for example, men's facial hair, women's breasts) is delayed in adolescents.
When Should I Call the Doctor About Growth Failure in Children?
See your doctor or health-care practitioner if you are concerned about your child's growth.
What Are the Exams and Tests to Diagnose Growth Failure in Children?
The doctor or health-care practitioner will measure the child's weight and height. He or she may also ask about the child's birth weight and birth height. The doctor may use the parents' heights to calculate the child's projected potential adult height. The doctor may also want to know the timing of puberty in the parents. The doctor may take measurements of the limbs and trunk to determine the child's body proportions.
The doctor may perform blood tests to check for hormones and to rule out specific syndromes associated with growth failure. The following blood tests may be performed:
- thyroxine and thyroid-stimulating hormone tests,
- serum electrolyte levels,
- complete blood count and sedimentation rate,
- insulin-like growth factor 1 and insulin-like growth
factor -- bindingprotein 3 tests, or a
- growth hormone stimulation test.
X-rays may be taken of the left wrist to compare with standard charts. This image can also be used to determine the child's bone age and growth potential.
What Medications Are Used to Treat Growth Failure in Children?
Growth hormone (somatotropin) is used to replace the body's lack of growth hormone. It is also used as a growth-promoting agent in certain conditions. Growth hormone, also known as somatropin (Nutropin, Genotropin, Humatrope, Norditropin, Saizen, Tev-Tropin, Omnitrope), is used to treat growth hormone deficiency. Usually, a significant increase in growth velocity occurs with therapy. During the first year, an average of about 4 inches (10-11 cm) per year occurs in growth in children with growth hormone deficiency and an average of 7-9 cm per year in growth occurs in children with other disorders. This drug is typically given as a daily injection underneath the fat of the skin, although clinical studies are underway that are examining preparations of growth hormone that would be injected only once weekly.
The U.S. Food and Drug Administration (FDA) has approved the use of growth hormone for promoting growth in children with Turner Syndrome (1996), Prader-Willi Syndrome (2000), Noonan Syndrome (2007), and children who were small for gestational age but have not caught up with their growth (2002). The FDA has also approved the use of growth hormone for what has been termed idiopathic short stature (ISS) (2003). Children with ISS are very short (height is less than or equal to the 1.2 percentile), are not growth hormone deficient, are not likely to finish their growth with a height in the normal range (meaning an adult height of less than 4' 11" for women and less than 5' 3" for men), and do not have a specific cause identified for their short stature.
In 2005, Insulin-like Growth Factor I was approved by the FDA for treatment of severe Growth Hormone Insensitivity Syndrome. This syndrome is usually caused by an abnormality in the growth hormone receptor and is very rare (there are probably no more than 500 people in the world with this condition). This medication is marketed under the name Increlex and is given as a once- or twice-daily injection. There has been some interest in studying whether this medication might be helpful in other situations in which growth hormone has been ineffective.
What Is the Follow-up for Growth Failure in Children?
The doctor or health-care practitioner may want to evaluate the child every three months while the cause of growth failure is being investigated. This also allows the doctor to obtain repeated growth measurements, which can then be used to estimate the child's growth rate.
The doctor may refer the child to a pediatric endocrinologist (a doctor who specializes in studying hormones) for a more detailed evaluation of the possible causes of growth failure.
How Can You Prevent Growth Failure in Children?
Routine well-baby checkups and periodic checkups for school-age and adolescent children is the best means of prevention.
What Is the Prognosis for Growth Failure in Children?
Early therapeutic intervention is important. Therapy should begin before the child's growth process is complete.
For children with hypothyroidism or growth hormone deficiency, hormone replacement therapy usually results in a period of rapid catch-up growth, with subsequent normal growth until the growth process is complete.
"Diagnostic approach to children and adolescents with short stature"