A 12-year-old boy is referred for tall stature, long limbs, arachnodactyly, pectus excavatum, lens dislocation (upward), and aortic root dilation of 4.2 cm. Molecular testing confirms FBN1 mutation. Which additional systemic feature requires URGENT monitoring?

• A Mitral valve prolapse with severe regurgitation
• B Pulmonary hypertension
• C Renal artery stenosis
• D Progressive aortic root dilation with risk of type A dissection ✓

Explanation

Marfan syndrome (FBN1 mutation on chromosome 15) is characterised by skeletal (arachnodactyly, tall stature), ocular (superotemporal ectopia lentis), and cardiovascular manifestations. The most life-threatening complication is progressive aortic root dilation leading to aortic dissection or rupture — this requires annual echocardiography, beta-blocker or losartan therapy to retard progression, and surgical intervention (aortic root replacement) when the diameter exceeds 4.5–5 cm or growth rate is >0.5 cm/year. Mitral valve prolapse occurs but is rarely the urgent concern. Pulmonary hypertension and renal artery stenosis are not features of Marfan syndrome.

Reference: Ghai Essential Pediatrics, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.