Burrill Bernard Crohn at Mount Sinai Hospital in 1907. He was promoted to head of gastroenterology in 1920, the same year he joined the staff of Columbia University. Working with colleagues at Mount Sinai Hospital, Crohn identified fourteen patients whose symptoms and intestinal abnormalities discovered at surgery, while consistent with each other, did not fit any previously identified disease. Crohn, along with Leon Ginzburg and Gordon Oppenheimer, prepared the classic paper describing this new condition. This paper was read at a professional meeting in May 1932 and published in the "Journal of the American Medical Association" in October 1932. The title of the
Crohn's disease Crohn's disease may develop anemia due to vitamin B, folate, iron deficiency, or due to anemia of chronic disease. The most common is iron deficiency anemia from chronic blood loss, reduced dietary intake, and persistent inflammation leading to increased hepcidin levels, restricting iron absorption in the duodenum. As Crohn's disease most commonly affects the terminal ileum where the vitamin B12/intrinsic factor complex is absorbed, B12 deficiency may be seen. This is particularly common after surgery to remove the ileum. Involvement of the duodenum and jejunum can impair the absorption of many other nutrients including folate. If Crohn's disease affects the