Table of ContentsView AllTable of ContentsAnatomyFunctionAssociated ConditionsSymptomsDiagnosis
Table of ContentsView All
View All
Table of Contents
Anatomy
Function
Associated Conditions
Symptoms
Diagnosis
Theduodenumis the first section of the small intestine. Roughly 8 to 10 inches in length in adults, the duodenum receives partially digested foods from the stomach and exposes them to digestive enzymes that break them down even further.
The duodenum is vulnerable to certain diseases that can affect its function, including ulcers, celiac disease, and cancer. Certain infections, medications, and lifestyle choices (like smoking and drinking) can also cause inflammation of the duodenum, referred to asduodenitis.
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The duodenum is a hollow, C-shaped section of thesmall intestinethat is connected to the stomach on one end and thejejunum(the middle portion of the small intestine) on the other.
Separating the duodenum and stomach is a muscular valve called thepyloric sphincter, which opens and closes to pass partially digested food. Separating the duodenum and jejeunum is theduodenojejunal flexure, which does not close and allows food to pass unobstructed.
Feeding into the duodenum is a thin tube called thecommon biliary ductthat releases digestive enzymes from theliverandpancreaswhenever food enters.
The walls of the duodenum are made of four layers, each of which serves different purposes:
The primary function of the duodenum is to continue the process of digestion after partially digested food (calledchyme) leaves the stomach.
The process and function of the duodenum can be broadly described as follows:
Conditions Affecting the Duodenum
The duodenum is vulnerable to certain diseases and infections, some of which are more common than others. These include:
Signs and Symptoms of Duodenal Disease
Duodenal diseases can differ in their symptoms, including whether the symptoms areacute(sudden and severe) orchronic(persistent or recurrent). In many cases, there will be no symptoms at all, and the condition may only be detected during an investigation of an unrelated problem.
Even so, there are common signs and symptoms when duodenitis or duodenal ulcers develop, including:
If you have symptoms of duodenitis or duodenal disease, you may be referred to a specialist in the diseases of the digestive tract known as agastroenterologist.
Several tests are commonly used to diagnose duodenal diseases, including:
Summary
Signs of duodenal disease include upper right abdominal pain, indigestion, bloating, and dark or tarry stools. A variety of tests and procedures can be used to pinpoint the cause, including stool tests, a urea breath test, upper endoscopy, and a duodenal biopsy.
9 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.MedlinePlus.Duodenum.Clarke L, Feakins RM.Chapter 14 - duodenitis. In:Non-Neoplastic Pathology of the Gastrointestinal Tract. Cambridge, MA: Cambridge University Press; 2020:206-214.Sensoy I.A review on the food digestion in the digestive tract and the usedin vitromodels.Curr Res Food Sci.2021;4:308–319. doi:10.1016/j.crfs.2021.04.004American College of Gastroenterology.Peptic ulcer disease.National Institute of Diabetes and Digestive and Kidney Diseases.Definitions and facts for celiac disease.Pimentel AM, Rocha R, Santana GO.Crohn’s disease of esophagus, stomach and duodenum.World J Gastrointest Pharmacol Ther.2019 Mar 7;10(2):35–49. doi:10.4292/wjgpt.v10.i2.35U.S. Department of Health and Human Services. National Institutes of Health.Duodenal atresia.Nakagawa K, Sho M, Fujishiro M, et al.Clinical practice guidelines for duodenal cancer 2021.J Gastroenterol.2022;57(12):927–941. doi:10.1007/s00535-022-01919-ySrisajjakul S, Paapaisilp P, Bangchokdee S.Imaging spectrum of nonneoplastic duodenal diseases.Clin Imaging. 2016 Nov-Dec;40(6):1173-1181. doi:10.1016/j.clinimag.2016.08.007
9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.MedlinePlus.Duodenum.Clarke L, Feakins RM.Chapter 14 - duodenitis. In:Non-Neoplastic Pathology of the Gastrointestinal Tract. Cambridge, MA: Cambridge University Press; 2020:206-214.Sensoy I.A review on the food digestion in the digestive tract and the usedin vitromodels.Curr Res Food Sci.2021;4:308–319. doi:10.1016/j.crfs.2021.04.004American College of Gastroenterology.Peptic ulcer disease.National Institute of Diabetes and Digestive and Kidney Diseases.Definitions and facts for celiac disease.Pimentel AM, Rocha R, Santana GO.Crohn’s disease of esophagus, stomach and duodenum.World J Gastrointest Pharmacol Ther.2019 Mar 7;10(2):35–49. doi:10.4292/wjgpt.v10.i2.35U.S. Department of Health and Human Services. National Institutes of Health.Duodenal atresia.Nakagawa K, Sho M, Fujishiro M, et al.Clinical practice guidelines for duodenal cancer 2021.J Gastroenterol.2022;57(12):927–941. doi:10.1007/s00535-022-01919-ySrisajjakul S, Paapaisilp P, Bangchokdee S.Imaging spectrum of nonneoplastic duodenal diseases.Clin Imaging. 2016 Nov-Dec;40(6):1173-1181. doi:10.1016/j.clinimag.2016.08.007
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
MedlinePlus.Duodenum.Clarke L, Feakins RM.Chapter 14 - duodenitis. In:Non-Neoplastic Pathology of the Gastrointestinal Tract. Cambridge, MA: Cambridge University Press; 2020:206-214.Sensoy I.A review on the food digestion in the digestive tract and the usedin vitromodels.Curr Res Food Sci.2021;4:308–319. doi:10.1016/j.crfs.2021.04.004American College of Gastroenterology.Peptic ulcer disease.National Institute of Diabetes and Digestive and Kidney Diseases.Definitions and facts for celiac disease.Pimentel AM, Rocha R, Santana GO.Crohn’s disease of esophagus, stomach and duodenum.World J Gastrointest Pharmacol Ther.2019 Mar 7;10(2):35–49. doi:10.4292/wjgpt.v10.i2.35U.S. Department of Health and Human Services. National Institutes of Health.Duodenal atresia.Nakagawa K, Sho M, Fujishiro M, et al.Clinical practice guidelines for duodenal cancer 2021.J Gastroenterol.2022;57(12):927–941. doi:10.1007/s00535-022-01919-ySrisajjakul S, Paapaisilp P, Bangchokdee S.Imaging spectrum of nonneoplastic duodenal diseases.Clin Imaging. 2016 Nov-Dec;40(6):1173-1181. doi:10.1016/j.clinimag.2016.08.007
MedlinePlus.Duodenum.
Clarke L, Feakins RM.Chapter 14 - duodenitis. In:Non-Neoplastic Pathology of the Gastrointestinal Tract. Cambridge, MA: Cambridge University Press; 2020:206-214.
Sensoy I.A review on the food digestion in the digestive tract and the usedin vitromodels.Curr Res Food Sci.2021;4:308–319. doi:10.1016/j.crfs.2021.04.004
American College of Gastroenterology.Peptic ulcer disease.
National Institute of Diabetes and Digestive and Kidney Diseases.Definitions and facts for celiac disease.
Pimentel AM, Rocha R, Santana GO.Crohn’s disease of esophagus, stomach and duodenum.World J Gastrointest Pharmacol Ther.2019 Mar 7;10(2):35–49. doi:10.4292/wjgpt.v10.i2.35
U.S. Department of Health and Human Services. National Institutes of Health.Duodenal atresia.
Nakagawa K, Sho M, Fujishiro M, et al.Clinical practice guidelines for duodenal cancer 2021.J Gastroenterol.2022;57(12):927–941. doi:10.1007/s00535-022-01919-y
Srisajjakul S, Paapaisilp P, Bangchokdee S.Imaging spectrum of nonneoplastic duodenal diseases.Clin Imaging. 2016 Nov-Dec;40(6):1173-1181. doi:10.1016/j.clinimag.2016.08.007
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