Which specialist should an 18‑year‑old female with suspected Marfan syndrome be referred to for evaluation?

Specialist Referral for Marfan Syndrome Evaluation

An 18-year-old female with suspected Marfan syndrome should be referred to a medical geneticist as the primary specialist for comprehensive evaluation and diagnosis. 1

Primary Referral: Medical Geneticist

The American College of Medical Genetics (ACMG) guidelines explicitly state that individuals suspected of having Marfan syndrome are most appropriately referred to a medical geneticist for further evaluation and diagnosis. 1 This is the standard of care because:

• Medical geneticists are specifically trained to apply the revised Ghent diagnostic criteria, which require systematic assessment of multiple organ systems and interpretation of genetic testing results 1
• They can distinguish Marfan syndrome from mimicking conditions including Loeys-Dietz syndrome, Ehlers-Danlos syndrome, familial thoracic aortic aneurysm, and at least 10 other overlapping connective tissue disorders 1
• They coordinate the multidisciplinary evaluation required for accurate diagnosis 2, 3

Essential Concurrent Referrals

While the medical geneticist serves as the diagnostic coordinator, two additional specialists must be involved early in the evaluation process:

Cardiologist

• Required for echocardiographic assessment of aortic root dimensions, which is essential whenever Marfan syndrome is seriously considered 1
• Critical for risk stratification since the primary concern driving evaluation is the risk of progressive aortic dilatation and dissection, particularly related to physical activity 1
• The echocardiogram is non-negotiable and must measure aortic root dimension relative to body surface area 1

Ophthalmologist

• Slit-lamp examination with fully dilated pupils is essential to exclude or confirm ectopia lentis, a cardinal diagnostic feature 1
• Must be an ophthalmologist comfortable with ocular features of Marfan syndrome, not just a general eye examination 1

Why This Algorithmic Approach

The guideline evidence is clear that cardiologists alone are frequently consulted about tall, thin adolescents out of concern for Marfan syndrome, but they often struggle with whether the diagnosis can be established and whether further testing is necessary. 1 Similarly, sports medicine physicians may see these patients for activity clearance but lack the comprehensive diagnostic framework. 1

The medical geneticist provides the diagnostic expertise to properly apply the revised Ghent criteria, which now emphasize aortic root dilation, ectopia lentis, and FBN1 mutation testing as the three pillars of diagnosis. 1 They can determine when molecular genetic testing is indicated and interpret results appropriately, recognizing that FBN1 testing detects mutations in only 90-95% of unequivocal cases. 1

Critical Pitfall to Avoid

Do not assume a normal echocardiogram rules out Marfan syndrome or eliminates the need for geneticist evaluation. While a normal aortic root dimension reduces immediate dissection risk in most conditions, Loeys-Dietz syndrome (a Marfan mimic) can cause dissection even without significant aortic dilatation. 1 Only a medical geneticist can properly distinguish these conditions and establish appropriate long-term surveillance. 1

Multidisciplinary Team Structure

Once diagnosis is established or strongly suspected, ongoing management requires a coordinated team including cardiologists, ophthalmologists, orthopedists, and potentially other specialists depending on manifestations. 4, 2, 5 However, the initial diagnostic evaluation should be anchored by medical genetics, with cardiology and ophthalmology providing essential diagnostic data. 1