Marfan syndrome may be difficult to diagnose because signs of the condition vary greatly from one person to the next. Most affected people will not have all the signs and complications of Marfan syndrome.
Diagnosis can be confirmed within a family by genetic linkage studies. Mutations can be found in the fibrillin-1 gene in 92% of patients, assisting with screening of family members.
The identification of the causative gene in 1991, in which the mutations for the Marfan syndrome are located, offered great promise as a diagnostic aid. Earlier and more accurate diagnosis of Marfan syndrome is now possible through screening for changes (mutations) in this gene.
Blood tests demonstrating the abnormal gene are available through referral to a clinical geneticist.
Prenatal diagnosis is now available for some families with this condition, where a mutation (change) in the fibrillin-1 gene has been demonstrated. Preimplantation genetic diagnosis may enable affected parents to have unaffected children.
In general, Marfan syndrome is diagnosed after careful physical examination, particularly focusing on the main systems involved; eyes, skeleton, heart and lungs. Major involvement in two out of three systems is required for a clinical diagnosis.
Certain tests, such as an echocardiogram (a sound wave picture of the heart) are useful in making the diagnosis.
- People with Marfan syndrome should have an initial diagnostic echocardiogram which is repeated at regular intervals.
- An Electrocardiogram (ECG) is not adequate screening.
- Skeletal X-rays (mainly chest and back) may be necessary, and a careful eye examination using slit lamp to detect lens dislocation, is recommended.
- Family history also needs to be taken into account.
Source: The Marfan Trust