ISS is a term used to cover a wide range of conditions that are associated with short stature. Idiopathic generally refers to a condition which arises spontaneously or for which the cause is unknown. These conditions are difficult to diagnose and are often caused by unknown genetic factors.
ISS can be caused by mutations to genes involved in the function of growth hormones and growth plate physiology; however, many causes are still unknown.
The symptoms of ISS can vary greatly. The main sign of ISS is reduced growth and short stature.
To diagnose ISS, the healthcare professional will need to rule out other recognisable causes of short stature. This complex diagnosis includes a thorough history and physical examination, growth calculations, assessment of bone age, and eventually some laboratory investigations. In the future, as more cases of ISS are identified, we will understand more about the causes of the disorder and diagnosis may become easier.