Medicines for Achondroplasia

What it is

Achondroplasia is a genetic condition affecting the growth of bones, and is the most common cause of short-limbed dwarfism (restricted growth). It is caused by a change in a gene (FGFR3) that affects how cartilage is turned into bone, particularly in the long bones, so that they grow less than usual. Most cases arise from a new gene change (with no family history), though it can be inherited. The main feature is short stature with disproportionately short arms and legs (particularly the upper arms and thighs), an average-sized trunk, and a larger head with characteristic facial features; other features can include specific patterns of joint and spine development. Importantly, intelligence is typically normal, and most people with achondroplasia have a normal life expectancy and lead full, independent lives. However, there are certain specific health aspects that need monitoring and, sometimes, treatment — such as, in infancy, monitoring head growth and the junction between the skull and spine; ear infections and hearing (which need attention to protect speech and development); dental crowding; spinal issues (such as narrowing of the spinal canal that can develop, particularly in adulthood); and sleep-related breathing problems in some. Understanding the condition, and monitoring these specific aspects, is the basis of good care.

How it is treated

Achondroplasia is managed with monitoring and support tailored to its specific health aspects, usually with input from specialists, while recognising that most people lead full, independent lives with normal intelligence and life expectancy. Care includes: regular monitoring in childhood (of growth, head size, development, and the specific features that need watching); prompt attention to ear infections and hearing (to protect speech and learning); dental care for crowding; and monitoring for and managing spinal problems (such as spinal canal narrowing, which can cause nerve symptoms, particularly in adults) and any sleep-related breathing problems. Some children may benefit from a specific treatment that can improve growth (a medicine that has become available in recent years for achondroplasia), which specialists discuss where appropriate. Practical support, adaptations, and support organisations help with day-to-day aspects and any challenges, and it is important to support wellbeing and inclusion, and to challenge stigma. Genetic counselling is offered to explain the condition, inheritance, and implications for the family. The reassuring message is that achondroplasia is a condition in which intelligence and life expectancy are usually normal and people lead full lives, and that care centres on monitoring and managing its specific health aspects, with support tailored to the individual and family.