It is the condition resulting from a deficiency of Growth Hormone (GH), GHRH or IGF-I. Most instances of dwarfism result from a generalized deficiency of anterior pituitary secretion during childhood. It can be caused by any of more than 200 conditions. Causes of proportionate dwarfism include metabolic and hormonal disorders such as growth hormone deficiency. Dwarfism itself is not a disease and, as a result, it has no single medical definition.
Types and Feature:
(A) Lorain levy type (infantilism)
- Stunted growth (adult about 85 cm or 3 feet)
- Sex organs and secondary sex characters do not grow. Hence an adult man resembles a normal child.
- Intelligence-normal and proportional to age.
(B) Brissaud type (Fat body of Dickens)
Features – Same as Lorain-levy type plus excess deposition of fat in the body, round flabby face, no beard or mustache, sleepy and slothful nature.
(C) Mixed type
- Mixed histological nature and combined clinical manifestation.
- The subject may be hairless.
- Large accessory nasal sinus, prominent supra orbital ridge.
Other types of dwarfism –
- African pygmies – They lack IGF – I.
- Psychosocial dwarfism – Chronic abuse and negligence cause this type of dwarfism.
- Achondroplasia – Mutation Fibroblast Growth Factor Receptor – 3 (FGFR 3).
- Gonadal dysgenesis.