Crohn's disease is a 55% chance the other will too. The incidence of Crohn's disease is increasing in Europe and in newly industrialised countries. For example, in Brazil, there has been an annual increase of 11% in the incidence of Crohn's disease since 1990. Inflammatory bowel diseases were described by Giovanni Battista Morgagni (1682–1771) and by Scottish physician T. Kennedy Dalziel in 1913. "Ileitis terminalis" was first described by Polish surgeon Antoni Leśniowski in 1904, although it was not conclusively distinguished from intestinal tuberculosis. In Poland, it is still called Leśniowski-Crohn's disease (). Burrill Bernard Crohn, an American gastroenterologist at New York
Sickle cell disease that sickle cell disease affects 90,000 Americans. Most infants with SCD born in the United States are now identified by routine neonatal screening. As of 2016 all 50 states include screening for sickle cell disease as part of their newborn screen. Patient advocates for sickle cell disease have complained that it gets less government and private research funding than similar rare diseases like cystic fibrosis, with researcher Elliott Vichinsky saying this shows racial discrimination or the role of wealth in health care advocacy. As a result of population growth in African-Caribbean regions of overseas France and immigration from North and