Pituitary Dwarfism


What is Pituitary Dwarfism?

Pituitary dwarfism is a medical condition in which the pituitary gland is unable to secrete adequate amounts of growth hormone necessary for initiating growth and development of muscles. Without signalling from the pituitary gland, the ability to of the body’s bones and muscles to attain maximum size potential is heavily impaired, resulting into a mature, adult body but heavily stunted in terms of size.

The person’s intelligence and mental capabilities, however, are intact. Pituitary dwarfism is an avoidable complication. If the child is not diagnosed early on and the epiphyseal plates close at 16-18 years old, the doors for growth and development to attain optimal size of an adult body close forever.

Giving growth hormone supplementation at this time will only result in acromegaly in which the body will grow “sideways”. If the child is diagnosed and given supplementation at an early age, the child can go on to grow and attain a normal adult body without complications.

Growth hormone is secreted optimally at night when the child is sleeping, hence the advice that young children should sleep more and avoid activities or drugs (such as coffee) that may interfere with sleep.

We will begin a short review of the endocrine gland in relation to its malfunction that leads to pituitary dwarfism.

endocrine system

Image 1. The Endocrine System.

Pathophysiology

The hypothalamus is the seat of control in managing the release of hormones that influence varies functions in the human body. The hypothalamus receives stimuli from the internal and external environment which it responds to by sending different hormones for different scenarios.

For the purposes of our discussion, we will focus on the hypothalamus-pituitary-target organ axis. The hypothalamus secretes Growth Hormone-Releasing Hormone, a naturally occurring peptide hormone.

This hormone is present in the human conceptus at 18-29 weeks of gestation. Constantly produced in a pulsatile manner, this hormone causes the stimulation of the anterior pituitary gland to produce Growth Hormone which in turn is released into the general circulation and then stimulates the bones and the muscles to grow at an exponential rate.

This hormone is responsible for stimulating cartilage, bone and muscles cells to grow rapidly in the early years of life and is stimulated again at puberty. This explains the rapid development from the childhood phase to adolescence and into early adulthood where growth is optimal.

The hormone is responsible also for a myriad of other inter-related body functions which supplement and complement the growth and development process. Outlined here are some processes including growth and development of all other organs not mentioned except the brain, calcium mineralization of the bone; this strengthens the bone, stimulation of the immune system as well as up regulating the thyroid’s metabolic function.

There is a medical condition that comes about when there is an excess of the growth hormone. This is called as gigantism; this condition is when there is an overgrowth of the human body to sizes which are classified as being well above the average mean height for a particular race such as Asian or Caucasian bodies.

This also translates to medical complications that come about with increased body mass. Conditions include high blood pressure (to compensate for gravity pulling blood down), diabetes, and sleep apnea and heart failure.

What defect causes Pituitary Dwarfism?

The growth hormone that is needed to stimulate growth and development is either missing or secreted in inadequate amounts. Little to no development occurs and the patient’s growth is stunted.

pituitary dwarfism

Image 2: A famous dwarfism case.

But despite the lack of size development, the patient’s mental capacities are retained.

Signs and symptoms

The principle sign and symptom is unusual shortness with proportionality of body size. Most dwarfs are classified if they have heights less than 4 feet and 10 inches. Bone complaints are common, owing to a nerve compression or impairment in pulmonary development. But for most sufferers of pituitary dwarfism, the psychological complications are much more disabling.

Social prejudice is associated with dwarfs as they are less able to acquire decent paying jobs as well as reduced marriage opportunities. They have reduced self-esteem and this has an effect on both their daily activities of living as well as emotional health. They may also be prone to teasing and ridicule by their peers which lead to isolationism.

Diagnosis

The diagnosis of pituitary dwarfism has to be confirmed by blood tests; measuring the blood levels of growth hormone or growth hormone-releasing hormone. A majority of growth hormone deficiency occurs because of the existence of anterior pituitary tumors. A good history and physical examination and diagnostics can lead to the right diagnosis.

Treatment

After the cause is determined and the tumor removed, supplementation of growth hormone as the pharmaceutical “somatotropin” can begin and can be customized to mimic the body’s own pulsatile secretion of growth hormone.

If the supplementation is done correctly, the child is able to achieve the same height, growth and development as his normal peers. Caution should be taken however, if there is an attempt to administer growth hormone after the epiphyseal plates close, this inevitably leads to acromegaly where there is a growth of the peripheries disproportionate to the central body.

Prevention

As there can be no way to tell immediately at birth if the child is missing growth hormone, regular medical check-ups on the child’s growth and development should be documented if this follows the mean average.

If ever the parent can note that there is something lacking in the growth and development, the parent can seek consult with a medical professional who will provide the necessary interventions to diagnose and treat pituitary dwarfism.

Conclusion

Indeed pituitary dwarfism is a psychologically disabling medical condition. The effects are shown in a society that places a premium on height. In order to prevent such complications, the parents of these possible pituitary dwarfism sufferers should take the necessary steps to help their child achieve the best growth and development.

Have the child be checked up via newborn screening to watch out for potential diseases that may have significant impact in later life. As they say, prevention is better than cure.

Pictures

Pituitary Dwarfism dwarfism pituitary tumors

Pituitary Dwarfism gigantism normal growth

Leave a Reply

Your email address will not be published.