What is Dwarfism?
Dwarfism means a child is abnormally short compared to contemporaries of the same age and racial origin.
Abnormal shortness is not always associated with a defect of the pituitary mechanism, for it may be related to many other fairly common medical ailments. For example, malnutrition could prevent normal physical development. The food eaten may not be adequately absorbed by the system, as occurs in coeliac disease and mucoviscidosis. Inadequate oxygen in congenital heart disorders or the prolonged use of cortisone like drugs in asthma may be an underlying cause. It is now known that corticosteroid drugs (cortisone like preparations) may suppress the secretion of growth hormone by the pituitary so growth is retarded in this roundabout manner.
Inadequate thyroid hormone may be the basic cause, or the growing bones may fuse prematurely if there is a premature secretion of male hormones as occurs in precocious sexual maturity. It is interesting to note that women are usually shorter than men because the menarche (when secondary sexual characteristics start to develop due to the presence of female hormones) takes place usually about two years before the male equivalent; so males have a longer period in which to grow.
Familial factors may also play a part. With the African pygmies there is an inherited lack of response to the normal levels of growth hormone, so they simply do not grow at the normal rate. Why growth hormone is not secreted in some people is not known. Some claim it may be due to birth injury during or after delivery, in which case it may later be associated with lack of other trophichormones. Sometimes it is due to an inherited familial disorder.
Depending on the cause, the reduction in growing rate may be only a minor part of the general symptoms, the symptoms due to the other basic disorders being of greater import and more noticeable.
Dwarfism as such, and due to deficiency of HGH (human growth hormone), usually becomes apparent after the age of two years. At this age, the rate of growth has already started to slow down. Often medical assistance is not sought until the age of puberty, when the parents are suddenly alarmed at the lack of sexual development that normally occurs at this time.
The patients have normal intellect and are certainly in no way grotesque. They merely have infantile skeletal proportions, and may be likened to “Tom Thumb” of storybook fame.
Abnormal shortness is sometimes, though not always, associated with a defect of the pituitary mechanism. Other factors could include inadequate nutrition, inadequate thyroid hormone, premature secretion of the male hormones, or inherited family disorders.
In neither sex does puberty occur: in boys the testes may be undescended (in itself another difficulty and one that must be quickly attended to, for it may produce its own set of problems, chiefly the risk of the undescended testes turning cancerous).
Sometimes other symptoms may dominate the picture if there is a basic defect affecting, for example, the nervous system.
In children the use of human growth hormone has made a revolutionary difference to their future. Injections may be given twice a week. The outlook for many is excellent. “The prognosis in terms of stature is good when the cause of dwarfism is a systemic disease that can be cured or controlled,” Price says. However, it seems that about 25 per cent of patients treated with growth hormone may develop antibodies and become unresponsive after an initial improvement.
On the other hand, others claim that “children with growth hormone deficiency who are short and whose epiphyses have not fused, may benefit from injections of human growth hormone.” the British Medical Journal writers said not long ago.
Growth hormone was originally made from human sources. But this suddenly encountered trouble when a virus appeared to be transmitted in the material injected into the patient. Although rare, it halted its further use. However, soon after, nonhuman supplies were manufactured by DNA recombinant technology.
This is now readily available, and widely used without any fear of the previous adverse side effects.
This again is one of the major developments in the past few years. More drugs will be prepared by recombinant technology. Recombinant insulin is the other most widely used product.
Dwarfs, we are not making a trip to darkest Africa, surely? We are certainly not. But sometimes a child may be deficient in a pituitary hormone chemical called the growth hormone. This may result in the stature being much below normal and a condition referred to as “dwarfism” taking place. There may also be other symptoms of reduced development, such as in the limbs, hands, feet, genital organs. There may be bulging eyes and a high-pitched voice. A tumor is the most likely reason, although other causes may exist.