Gigantism is characterized by abnormal growth in children due to excessive production of insulinlike growth factor I (IGF-I). Basically there is excess production of growth hormone which contributes to the accelerated linear growth.
Children with gigantism are taller than other age matched children. In many instances, certain parts are proportionately bigger than other parts. Affected children can also have long hands and feet, with signs of thickening of fingers and toes along with a prominent forehead and jaw. Children with gigantism may also have coarse facial features which include a larger than normal head, flat nose, and large lips and tongue.
Symptoms of gigantism largely depend on the size of the tumor on the pituitary gland. When the tumor gradually increases in size, it may exert pressure on the neighboring nerves in the brain. This may further cause the children to suffer from headaches or loss of vision. In addition, children would also experience weakness, fertility problems, delay in onset of puberty and excessive sweating. In severe cases, deafness can also set in .
Measuring the blood levels of growth hormone and insulinlike growth factors forms the preliminary basis of diagnostic procedure. Another method of measuring the insulinlike growth factor is to determine the levels about 1 hour after administration of a glucose load. Under normal circumstances, the hormone levels decrease after a glucose load. In children with gigantism, the values remain normal even after consuming glucose. This indicates that the body produces excessive growth hormones, which causes the levels to remain normal . Imaging studies such as CT scan and MRI are indicated to detect the location as well as size of the tumor in the pituitary gland.
Treatment of gigantism is aimed at slowing down the progression of production of growth hormones as well as effective management of symptoms. The following methods are employed in order to fulfill the objectives:
Research has shown that, about 80% of cases can be successfully treated with surgery to remove the tumor. In situations, when surgery cannot be successfully accomplished then medications are employed for effective management of symptoms. In either of the cases, individuals can live a long and healthy life .
Development of a tumor in the pituitary gland is the major cause of gigantism. Excessive release of growth hormone due to a benign tumor in the pituitary gland favors abnormal growth development in children .
In addition to excess production of growth hormones, gigantisms can also occur as a result of other conditions, which include neurofibromatosis, Carney complex, multiple endocrine neoplasia type I, tuberous sclerosis and McCune-Albright syndrome. It has been estimated that, about 20% patients suffering from gigantisms also suffer from McCune-Albright syndrome .
Gigantism is a rare phenomenon, and only about 100 cases are reported till date. The condition of acromegaly is more common than gigantism, with a reported incidence of 3 – 4 cases per million each year; having a prevalence rate of 40 – 70 cases per million population. Gigantism can strike at any age before the epiphyseal fusion takes place. Agromegaly occurs in the third decade of life; with mean age of diagnosis being 40 years and 54 years in females and males respectively . No sex predilection is known.
The excess production of insulinlike growth factor can be divided into the following factors:
Gigantism cannot be prevented. However, with early initiation of treatment, the onset of complications can certainly be kept at bay.
Gigantism occurs during childhood, much before the epiphyseal growth plates have closed. Early diagnosis along with prompt initiation of treatment is important for arresting the accelerated growth pattern. However, many parents fail to recognize that their child is suffering from gigantism as they consider the sudden growth as normal childhood growth spurts. Individuals with gigantism measure between 2.13 m to 2.74 m .