A female patient with Turner syndrome undergoes karyotyping showing 45,X. In Turner syndrome, which organ system abnormality is the leading cause of morbidity and mortality in adults?

• A Renal — horseshoe kidney and double collecting system with recurrent UTIs
• B Cardiac — bicuspid aortic valve and aortic coarctation with risk of aortic dissection ✓
• C Ovarian — streak gonads with gonadoblastoma risk
• D Lymphatic — congenital lymphedema causing chronic limb swelling

Explanation

Cardiovascular abnormalities are the most significant source of adult morbidity and mortality in Turner syndrome. Bicuspid aortic valve occurs in ~30–50% of patients and aortic coarctation in ~10–20%. Even after coarctation repair, patients with Turner syndrome have significantly elevated lifetime risk of aortic dissection and rupture due to underlying aortopathy with cystic medial degeneration — analogous to Marfan syndrome. While streak gonads with gonadoblastoma risk (especially in 45,X/46,XY mosaicism) is important, cardiac causes dominate adult mortality.

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.