Intestinal atresia


00:00 / 00:00



Intestinal atresia

Gastrointestinal system

Peritoneum and peritoneal cavity disorders



Upper gastrointestinal tract disorders

Cleft lip and palate

Congenital diaphragmatic hernia

Esophageal web

Tracheoesophageal fistula

Pyloric stenosis



Oral candidiasis

Ludwig angina

Aphthous ulcers

Temporomandibular joint dysfunction

Dental abscess

Gingivitis and periodontitis

Dental caries disease

Oral cancer

Warthin tumor

Barrett esophagus


Plummer-Vinson syndrome

Mallory-Weiss syndrome

Boerhaave syndrome

Gastroesophageal reflux disease (GERD)

Zenker diverticulum

Diffuse esophageal spasm

Esophageal cancer

Eosinophilic esophagitis (NORD)


Gastric dumping syndrome

Peptic ulcer


Cyclic vomiting syndrome


Gastric cancer

Lower gastrointestinal tract disorders


Imperforate anus


Meckel diverticulum

Intestinal atresia

Hirschsprung disease

Intestinal malrotation

Necrotizing enterocolitis


Tropical sprue

Small bowel bacterial overgrowth syndrome

Celiac disease

Short bowel syndrome (NORD)

Lactose intolerance

Whipple's disease

Protein losing enteropathy

Microscopic colitis

Crohn disease

Ulcerative colitis

Bowel obstruction

Intestinal adhesions


Gallstone ileus

Abdominal hernias

Femoral hernia

Inguinal hernia

Small bowel ischemia and infarction

Ischemic colitis

Familial adenomatous polyposis

Peutz-Jeghers syndrome

Gardner syndrome

Juvenile polyposis syndrome

Colorectal polyps

Colorectal cancer

Carcinoid syndrome

Irritable bowel syndrome


Diverticulosis and diverticulitis


Anal fissure

Anal fistula


Rectal prolapse

Liver, gallbladder and pancreas disorders

Crigler-Najjar syndrome

Biliary atresia

Gilbert's syndrome

Dubin-Johnson syndrome

Rotor syndrome



Portal hypertension

Hepatic encephalopathy


Wilson disease

Budd-Chiari syndrome

Non-alcoholic fatty liver disease

Cholestatic liver disease

Hepatocellular adenoma

Autoimmune hepatitis

Alcohol-induced liver disease

Alpha 1-antitrypsin deficiency

Primary biliary cirrhosis

Primary sclerosing cholangitis


Neonatal hepatitis

Reye syndrome

Benign liver tumors

Hepatocellular carcinoma


Biliary colic

Acute cholecystitis

Ascending cholangitis

Chronic cholecystitis

Gallstone ileus

Gallbladder cancer


Acute pancreatitis

Pancreatic pseudocyst

Chronic pancreatitis

Pancreatic cancer

Pancreatic neuroendocrine neoplasms

Zollinger-Ellison syndrome

Gastrointestinal system pathology review

Congenital gastrointestinal disorders: Pathology review

Esophageal disorders: Pathology review

GERD, peptic ulcers, gastritis, and stomach cancer: Pathology review

Inflammatory bowel disease: Pathology review

Malabsorption syndromes: Pathology review

Diverticular disease: Pathology review

Appendicitis: Pathology review

Gastrointestinal bleeding: Pathology review

Colorectal polyps and cancer: Pathology review

Neuroendocrine tumors of the gastrointestinal system: Pathology review

Pancreatitis: Pathology review

Gallbladder disorders: Pathology review

Jaundice: Pathology review

Viral hepatitis: Pathology review

Cirrhosis: Pathology review


Intestinal atresia


0 / 10 complete

USMLE® Step 1 questions

0 / 1 complete

High Yield Notes

11 pages


Intestinal atresia

of complete


USMLE® Step 1 style questions USMLE

of complete

A 2-day-old infant girl is observed to have several episodes of bilious vomiting while in the nursery. The vomiting is triggered by feeding. She was born full-term to a 38-year-old, gravida 2 para 2, female via vaginal delivery. The pregnancy was complicated by polyhydramnios. The patient’s vitals are notable for hypotension and tachycardia. Examination of the skull reveals sunken anterior and posterior fontanelles. The patient is also observed to have upslanted palpebral fissure and prominent epicanthal folds. A single transverse palmar crease is noted on the bilateral hands. The patient has a scaphoid abdomen. Digital rectal examination reveals normal rectal tone and no expulsion of gas or stool. Which of the following best describes the pathophysiology of this patient’s condition? 

External References

First Aid







Intestinal atresia p. 368

Necrosis p. 207

intestinal atresia p. 368


intestinal atresia p. 368

External Links


Content Reviewers

Rishi Desai, MD, MPH


Tanner Marshall, MS

With intestinal atresia, atresia refers to a passageway that’s closed or gone completely, so intestinal atresia is when a malformation during fetal development results an absent portion of the small or large intestine.

If instead the passageway was just narrowed, then it’s referred to as intestinal stenosis—oftentimes these are both just lumped together as intestinal atresia and stenosis.

The specific type of intestinal atresia is named depending on what section of the intestines is affected.

Duodenal atresia or stenosis is where the first section—the duodenum—is affected.

The underlying cause of duodenal atresia isn’t known, although it’s commonly associated with trisomy 21, also known as Down syndrome, suggesting that it’s likely due to genetic defects affecting normal development.

Although it isn’t known why intestinal atresia develops isn’t known, it is fairly well known how it develops.

Normally, early on in development, the gut’s a hollow tube.

But by around 6 weeks gestation, the epithelium of the duodenum proliferates and it ends up plugging up the lumen making it a completely solid stick of tissue.

After that, the cells in the middle undergo apoptosis, or programmed cell death, and by 9 weeks gestation, the tube’s hollow again, called recanalization.

This entire process is called vacuolation.

In duodenal atresia, this vacuolation process fails, and the duodenum doesn’t recanalize properly, resulting in atresia or stenosis of the duodenum.

Non-duodenal intestinal atresias or stenoses, like those affecting the jejunum or ileum, or even affected the large intestine like the colon, are generally not a result of recanalization, and instead are more likely to result from ischemic injury, meaning lack of bloodflow, to the developing gut.


  1. "Robbins Basic Pathology" Elsevier (2017)
  2. "Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2)" McGraw-Hill Education / Medical (2018)
  3. "Pathophysiology of Disease: An Introduction to Clinical Medicine 8E" McGraw-Hill Education / Medical (2018)
  4. "CURRENT Medical Diagnosis and Treatment 2020" McGraw-Hill Education / Medical (2019)
  5. "A case of duodenal atresia with apple peel appearance: Challenging the current embryology" Journal of Clinical Neonatology (2014)
  6. "Duodenal atresia and stenosis: long-term follow-up over 30 years" Journal of Pediatric Surgery (2004)

Copyright © 2023 Elsevier, except certain content provided by third parties

Cookies are used by this site.

USMLE® is a joint program of the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME). COMLEX-USA® is a registered trademark of The National Board of Osteopathic Medical Examiners, Inc. NCLEX-RN® is a registered trademark of the National Council of State Boards of Nursing, Inc. Test names and other trademarks are the property of the respective trademark holders. None of the trademark holders are endorsed by nor affiliated with Osmosis or this website.