Growth hormone is a chemical substance produced by a gland. Growth
hormone is crucial for normal growth and development.
In addition to causing children to grow taller, growth hormone plays a number of other vital roles, including:
· Ensuring strong, healthy bones
· Regulating the body’s metabolism, specifically the balance between muscle and fat
· Promoting general well-being and energy levels.
Growth hormone works by causing other hormones and growth factors to be produced in the body. These growth factors, along with growth hormone itself, travel through the bloodstream and cause growth and development to occur throughout the body.
Growth hormone deficiency (GHD) is a disease, where a child’s body fails to produce adequate amounts of growth hormone, resulting in growth retardation.
Growth hormone – called somatotropin—is a hormone designated to stimulate growth and cell reproduction in the body. This hormone is produced in the pituitary gland, which is located at the base of your brain, and then released into the blood.
GHD may be present at birth, or it may begin at any time during infancy or childhood. It is usually the result of the pituitary gland failing to produce adequate levels of growth hormone.
For most patients, the cause of growth hormone deficiency remains unknown. However, there are also several known causes, including:
· A tumour in the pituitary gland region
· Treatment of a brain tumour or cancer
· A genetic disorder
· Severe injury to the head
Without treatment a child with GHD will usually grow less than 4-5cm (~2inches) a year. Quite often, the child will grow normally until the age of 2 or 3 and then growth begins to slow down. This is the reason growth monitoring done through a growth charting is important. It is important to realize that a child may be smaller than average, but will have normal body proportions. In other words, children with GHD tend to seem younger and have more body fat than children of the same age who are growing normally.
Once a child is diagnosed as having GHD, daily growth hormone injections (to replace what the body is failing to produce) can help the child catch up with the growth of other children of the same age during early childhood. Continuing the injections helps maintain normal growth later in childhood, with the final aim of achieving an adult height within the normal range. The earlier the diagnosis of GHD in a child, the earlier treatment can be started and hence the better the prospects of their eventually reaching normal adult height.
If a child is born small for gestational age (meaning smaller than average in length and/or weight for a certain week of pregnancy) they may remain relatively small at a later age and even as an adult person.
The causes behind an infant being born SGA are quite complex, and may include:
· Factors associated with the mother's age
· Any infections contracted during pregnancy
· Alcohol intake
· Cigarette smoking
Other possible causes linked to SGA are a lack of oxygen reaching the unborn child through the blood supply from the placenta, or an inherited condition that affects the unborn child's growth. However, in around half of all cases, doctors cannot find any particular reason why a child is born SGA.
While 90% of infants born SGA grow fast enough to catch up with other children of their age, the remaining 10% of children born SGA are still small for their age by age 2. For these children, the risk of having short height when they reach adulthood is 5-7 times greater than for the normal child.
Once SGA has been diagnosed and children fail to attain catch up growth, growth hormone injections can help a child's growth catch up to normal height during early childhood. When growth hormone treatment is continued after this period, it helps to maintain normal growth later in childhood, with the aim of children eventually reaching an adult height within the normal range.
Turner’s syndrome is a genetic defect in girls which amongst other things, like medical, psychological and cosmetic issues results in growth retardation and infertility.
Children with TS are often of normal height for the first 2-4 years of their lives but then have a lower than average growth rate. this is due to a reduction in the effect of the growth hormone produced by the body in Turner girls. Later, when they reach puberty, the usual growth spurt fails to occur. Growth hormone treatment started earlier helps Turner patients to achieve a normal height before they reach their adulthood. Due to failure of the ovaries to function properly, oestrogen substitution is another important part of hormonal treatment in Turner girls and assists the development of feminine characteristics at puberty.
Growth hormone treatment, either alone or in conjunction with sex hormone replacement therapy, for example oestrogen, can significantly improve final adult height. It is important to understand that with appropriate medical treatment and support, a girl with TS can go on to lead a normal healthy and happy life.
Chronic renal disease (CRD), also called Chronic renal failure (CRF), is a condition where a child's kidneys no longer work well enough to maintain a normal state of health.
The kidney disease associated with CRD gradually affects the filtering capacity of the kidneys, resulting in symptoms which can include failure to grow properly.
The kidneys play a vital role in extracting waste products from the blood. In chronic renal disease, the kidneys fail to filter the blood properly. This creates an imbalance in body sodium and potassium as well as an excess build-up of blood acidity thereby affecting a child's growth. An imbalance in vitamin D, Calcium and phosphorus due to kidney disease may affect bone growth.
Today, through dialysis and kidney transplantation, even children with end-stage renal failure can live long, fruitful lives, and so treatment for short stature has become an even greater need.
Daily growth hormone injections can help a child catch up with the growth of other children of the same age during early childhood. Continuing the injections helps maintain normal growth later in childhood, with the final aim of achieving an adult height within the average range. The response to growth hormone treatment varies from one individual to another, but most children who receive treatment over several years remain within the normal growth range for their age.
Growth hormone continues to play an important role throughout adulthood, regulating metabolism and body composition, promoting strong bones and a healthy heart, and improving one’s general quality of life.
Without treatment, GHD in adults can cause various problems such as decreased vitality and lower ability to exercise, as well as poor memory. GHD can also have adverse effects on your body composition. these include:
1.An increased amount of body fat, especially around the middle of the abdomen.
2. An increase in total cholesterol circulating in the blood, leading to a greater risk of heart and arterial disease
3. A decrease in muscle mass, meaning that you are less able to exercise
4. A weakening in the structure of your bones, resulting in a condition called osteoporosis
Growth hormone deficiency that first appears in adulthood is called
acquired GHD. This can be the result of damage to the pituitary gland
due to disease, head injury or blockage of the blood supply. Damage
may also result from previous surgical or radiotherapy treatment of
the pituitary gland.
Growth hormone treatment may help adults with GHD normalize: weight, body fat distribution, muscle mass, bone mineral density, and energy levels, as a result one’s general sense of well-being will increase