Unlike most other MPS disorders, Morquio syndrome has no storage in the brain and sufferers are usually of completely normal intelligence. The condition is characterised by a severe abnormal development of the skeleton, resulting in short stature with an adult height of around 100cm.
In addition, severely affected patients are at risk of permanent neurological complications. The connective tissues of the cornea, airways and heart valves are also affected by the disease process. The effect on teeth is also quite marked.
Children with Morquio disease usually grow normally at first but growth may start to slow down around eighteen months. Those who are severely affected usually stop growing around the age of eight and their final height may be between 90 and 120 cms. Others continue growing into their teens and can reach 150 cm. The trunk is relatively shorter than the limbs.
The face is altered to a certain extent by the disease and the mouth tends to be wide, the jaw square and the bridge of the nose flattened. The neck is very short but the texture of the hair is not affected as it is in other MPS conditions. The chest is bell shaped and the ribs are held fixed in a horizontal position, causing restriction of efficient breathing.