SEARCH RESULTS FOR: Intestinal-Atresia

Intestinal Atresia

Intestinal Atresia: Pathogenesis and clinical findings
Developmental error
(e.g., Down Syndrome)
Intussusception Thromboembolism Intestinal hernia
Volvulus
Genetic defect impacts foregut
development during the 8th to
10th week of gestation
One part of the
intestine folds
into another in
utero which
blocks blood flow
Gestational blood
clot blocks intestinal
blood vessels
(e.g., superior
mesenteric artery)
Protrusion of the
intestines through
an abdominal
opening in utero
limits blood flow
The intestine twists
around itself in
utero, obstructing
blood flow
Inadequate or absent signaling
to initiate vacuolation (creation
of holes/vacuoles) of the
solid duodenum
↓ Perfusion of the jejunum, ileum or colon, leading to gut
ischemia à Gut tissue does not develop fully
The duodenal channel fails to open
Poorly developed ischemic tissue becomes necrotic & the body
reabsorbs it, creating blind ends (intestinal discontinuation)
Intestinal atresia
Complete occlusion of the intestinal (duodenal, jejunal, ileal or colonic) lumen, usually in the neonate
Authors:
Diana Changirwa
Skanda Kaushik
Reviewers:
Sergio Sharif
Nicholas Samuelson
Christopher N. Andrews*
Yan Yu*
* MD at time of publication
**See corresponding Calgary
Guide slide(s)
Occlusion in proximal small
Occlusion in proximal small bowel but after ampulla of Vater
bowel but after ampulla of Vater
(where the common bile duct releases bile into the small bowel)
Occlusion in distal small bowel
Secreted bile
cannot move
past occlusion
Gas & fluid
accumulate in
the stomach &
proximal
duodenum
Proximal obstruction
limits passage of
nutrients & intestinal
fluids through the
bowel
Intestinal secretions
& gas accumulate
proximal to
obstruction
Luminal distension
causes ↑ intestinal
pressure & ↓ intestinal
mucosal integrity
↑ Proliferation
of bacteria in
stagnant bowel
Bile refluxes
into the
stomach
Bilious
vomiting
Double-bubble sign
(dilated stomach &
proximal duodenum
on imaging)
Gut bacteria move
through mucosa &
enter bloodstream
Electrolyte
imbalances (e.g.,
hypokalemia)
Malnutrition
In neonate:
no
meconium
Complete
Abdominal
bowel
distention
obstruction
(first stool) Sepsis**
Legend: Published May 19, 2026 on www.thecalgaryguide.com
Pathophysiology Mechanism
Sign/Symptom/Lab Finding Complications