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Endocrine system

Gigantism If left untreated, gigantism can cause
Gigantism is a condition characterised by severe complications including overgrowth
excessive growth in children and adolescents of bones and tissues, and cardiovascular
due to an overproduction of growth issues such as increased size of the heart and
hormones before the closure of growth blood vessels that result in hypertension,
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plates in the bones. The most common heart disease, and even heart failure.
cause of gigantism is a pituitary tumour The untreated condition can also lead to
that secretes excessive Growth Hormone excessive weight that causes joint damage,
(GH). The tumour causes an overproduction leading to arthritis or other bone-related
of GH leading to an abnormal increase in issues. The elevated levels of IGF-1 may
the production of another hormone called result into insulin resistance may develop,
insulin-like growth factor 1 (IGF-1), which increasing the risk of Type 2 diabetes.
stimulates excessive growth. Other causes Gigantism typically cannot be prevented,
may include genetic mutations or certain especially if caused by genetic factors.
conditions that affect the pituitary gland. However, early diagnosis and treatment of
The most noticeable symptom is an increase pituitary tumours can help control excessive
in height due to excessive bone growth, growth.
enlargement of hands and feet, and enlarged
facial features, including the jaw, nose, and Dwarfism
forehead as shown in Figure 3.3. This condition is characterised by

shorter-than-average height, which is
typically the result of genetic factors
or hormonal imbalances. It can be
classified into proportionate dwarfism
and disproportionate dwarfism. A lack of
growth hormone production by the pituitary
gland is one of the most common causes
of dwarfism. This can occur due to genetic
mutations or damage to the pituitary gland.
Achondroplasia is among the most common
causes of disproportionate dwarfism. This
genetic disorder affects the growth of
bones, especially in the limbs, leading to
Figure 3.3: A dwarf person, normal person and a shorter stature with a larger torso (The
giant person torso refers to the central part of the human
Other symptoms may include, joint pain body, excluding the head, neck, arms, and
due to rapid growth making joints stiff or legs). In some cases, malnutrition during
painful, vision problems that occur if the childhood may also result in stunted growth.
tumour presses on the optic nerves, and The defining characteristic of dwarfism is
excessive sweating and fatigue.

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