A patient, born in 1961, is hospitalised for pubic abdominal pain with irradiation to the right and left sides. She has a Turner's syndrome. At first evaluation, an abdominal tomography demonstrates a right pyelonephritis. The patient is treated with quinolones and she evolves favourably, except that she continues to present some abdominal pain. She leaves the hospital, but because of permanent abdominal pain, a new abdominal tomography is performed: an aortic dissection type B for (Stanford), or III anterograde for (De Bakey), is diagnosed. Cardiovascular anomalies are frequent in Turner's syndrome. Aortic dissection is a rare complication. Histological analysis shows a cystic medial necrosis. Medical and cardiological follow-up is needed.