Ans: Duodenitis is referred to as the inflammation occurring in the duodenum. This inflammation in the various parts of the duodenum and the lining may cause severe abdominal pain, bleeding, and other gastrointestinal problems. Since the inner lining corrodes away due to inflammation and infection it is often referred to as erosive duodenitis. The mucus barrier is disrupted by the infection. As a result, the duodenal lining comes in contact with the acidic contents from the stomach. The loss of this mucus barrier results in duodenal ulcers and chronic inflammation of various parts of the duodenum. The erosive duodenitis is also caused by an infection from a bacteria called Helicobacter pylori. Among the other diseases related to duodenum, perforated duodenum is one.