Abstract
Turner syndrome (TS) is a genetic defect accompanied by gonadal dysgenesis, short stature, characteristic dysmorphic features, congenital heart and kidneys defects, and other diseases. One of the less common are vascular malformations in the gastrointestinal (GI) tract. They are asymptomatic in some patients, but can also cause GI bleeding. We present a description of a 12-year-old patient with TS and vascular malformations in the GI tract who was admitted to the hospital because of recurrent microcytic anemia. At the age of 15, she started estrogen therapy due to hypogonadism. Since then, the bleeding has stopped and the number of malformations on follow-up colonoscopy has been significantly decreased. In TS patients with iron deficiency anemia, the differential diagnostics should include vascular defects in the GI. There are evidences, that estrogen therapy may limit the number of lesions and reduce the risk of bleeding.