The Gastrointestinal Tract Part 1, UTHSC Fall
2022 D2 Pathology
what are some congenital abnormalities of the GI tract?
- Atresia, fistula
- Diaphragmatic hernia, omphalocele
- Ectopia
- Meckel diverticulum
- Pyloric stenosis
where can Atresia, Fistula happen?
- In any part of the GI tract
- In esophagus, with regurgitation during feeding
what are the effects of atresia?
a thin , noncanalized cord replaces a segment of esophagus
Atresia, most commonly at or near what area of the esophagus?
the tracheal bifurcation
what are the effects of a fistula?
aspiration, suffocation, pneumonia, and severe fluid and electrolytes imbalances
intestinal atresia are (more/less) common
less
fistula
abnormal passageway between two organs or between an internal organ and the body
surface
Diaphragmatic hernia
Herniation of the abdominal viscera into the thoracic cavity due to incomplete formation
of the diaphragm → pulmonary hypoplasia
Omphalocele
Herniation of the abdominal viscera into a ventral membranous sac due to incomplete
closure of the abdominal musculature
Ectopia
out of place tissue such as Ectopic Gastric Mucosa in Esophagus
Meckel Diverticulum
- A true diverticulum as a blind outpouching of the alimentary tract communicating with
the lumen and includes all 3 layers
- Meckel diverticulum in the ileum in 2% of the population
- Approximately 5 cm long
- Often symptomatic by age 2
Pyloric Stenosis
- Hyperplasia of the pyloric muscularispropria
- A complex multifactorial pattern of inheritance
- Increased risk with Turner syndrome and trisomy 18
- Erythromycin or azithromycin exposure and increased incidence
- Regurgitation, projectile, nonbilious vomiting after feeding
what are the general histologic layers of the GI system? (outer to inner)
- adventitia (esophagus/duodenum)/serosa (rest of GI tract)
- Muscularis externa
, - submucosa
- mucosa
- lumen
adventitia (esophagus/duodenum)/serosa (rest of GI tract)
connective tissue that supports and binds organs to others
Muscularis externa
smooth muscle, two to three layers
submucosa
connective tissue containing glands, blood vessels, and nerves
mucosa
epithelium, lamina propria, muscularis mucosa
Esophagus
A hollow, highly distensible muscular tube, extending from the epiglottis to the
gastroesophageal junction
what are the functions of the esophagus?
- Conduct food and fluids from the pharynx to the stomach
- Prevent reflux of gastric contents
Esophageal webs (EW)
Idiopathic ledge-like protrusions of mucosa that may cause obstruction
EW in women > 40 is associated with what?
GI reflux, chronic graft-versus-host disease, or blistering skin diseases
what is the main symptom of Esophageal Mucosal webs?
nonprogressive dysphagia
Plummer-Vinson Syndrome (Paterson-Brown-Kelly Syndrome)
- Upper esophagus webs, iron-deficiency anemia, glossitis, and cheilosis
- Increased risk for tongue cancer
Achalasia "Failure to Relax"
- Incomplete lower esophageal sphincter (LES) relaxation
- Increased LES tone
- Aperistalsis
what are the symptoms of Achalasia "Failure to Relax"?
- dysphagia, difficulty in belching, and chest pain
- Some increased risk for esophageal cancer
Primary achalasia is caused by?
distal esophageal inhibitory neuronal (ganglion cell) degeneration
Secondary achalasia
- Chagas disease, a Trypanosoma cruzi infection causing myenteric plexus destruction
- Diabetic autonomic neuropathy
- Infiltrative disorders (malignancy, amyloidosis, or sarcoidosis)
- Lesions of dorsal motor nuclei (e.g., polio)
- Dawn syndrome
- Occasional coexistence of Sjogren syndrome or autoimmune thyroid disease
Mallory-Weiss tears
mucosal tears near the gastroesophageal junction
- Most often associated with severe retching or vomiting secondary to acute alcohol
intoxication
2022 D2 Pathology
what are some congenital abnormalities of the GI tract?
- Atresia, fistula
- Diaphragmatic hernia, omphalocele
- Ectopia
- Meckel diverticulum
- Pyloric stenosis
where can Atresia, Fistula happen?
- In any part of the GI tract
- In esophagus, with regurgitation during feeding
what are the effects of atresia?
a thin , noncanalized cord replaces a segment of esophagus
Atresia, most commonly at or near what area of the esophagus?
the tracheal bifurcation
what are the effects of a fistula?
aspiration, suffocation, pneumonia, and severe fluid and electrolytes imbalances
intestinal atresia are (more/less) common
less
fistula
abnormal passageway between two organs or between an internal organ and the body
surface
Diaphragmatic hernia
Herniation of the abdominal viscera into the thoracic cavity due to incomplete formation
of the diaphragm → pulmonary hypoplasia
Omphalocele
Herniation of the abdominal viscera into a ventral membranous sac due to incomplete
closure of the abdominal musculature
Ectopia
out of place tissue such as Ectopic Gastric Mucosa in Esophagus
Meckel Diverticulum
- A true diverticulum as a blind outpouching of the alimentary tract communicating with
the lumen and includes all 3 layers
- Meckel diverticulum in the ileum in 2% of the population
- Approximately 5 cm long
- Often symptomatic by age 2
Pyloric Stenosis
- Hyperplasia of the pyloric muscularispropria
- A complex multifactorial pattern of inheritance
- Increased risk with Turner syndrome and trisomy 18
- Erythromycin or azithromycin exposure and increased incidence
- Regurgitation, projectile, nonbilious vomiting after feeding
what are the general histologic layers of the GI system? (outer to inner)
- adventitia (esophagus/duodenum)/serosa (rest of GI tract)
- Muscularis externa
, - submucosa
- mucosa
- lumen
adventitia (esophagus/duodenum)/serosa (rest of GI tract)
connective tissue that supports and binds organs to others
Muscularis externa
smooth muscle, two to three layers
submucosa
connective tissue containing glands, blood vessels, and nerves
mucosa
epithelium, lamina propria, muscularis mucosa
Esophagus
A hollow, highly distensible muscular tube, extending from the epiglottis to the
gastroesophageal junction
what are the functions of the esophagus?
- Conduct food and fluids from the pharynx to the stomach
- Prevent reflux of gastric contents
Esophageal webs (EW)
Idiopathic ledge-like protrusions of mucosa that may cause obstruction
EW in women > 40 is associated with what?
GI reflux, chronic graft-versus-host disease, or blistering skin diseases
what is the main symptom of Esophageal Mucosal webs?
nonprogressive dysphagia
Plummer-Vinson Syndrome (Paterson-Brown-Kelly Syndrome)
- Upper esophagus webs, iron-deficiency anemia, glossitis, and cheilosis
- Increased risk for tongue cancer
Achalasia "Failure to Relax"
- Incomplete lower esophageal sphincter (LES) relaxation
- Increased LES tone
- Aperistalsis
what are the symptoms of Achalasia "Failure to Relax"?
- dysphagia, difficulty in belching, and chest pain
- Some increased risk for esophageal cancer
Primary achalasia is caused by?
distal esophageal inhibitory neuronal (ganglion cell) degeneration
Secondary achalasia
- Chagas disease, a Trypanosoma cruzi infection causing myenteric plexus destruction
- Diabetic autonomic neuropathy
- Infiltrative disorders (malignancy, amyloidosis, or sarcoidosis)
- Lesions of dorsal motor nuclei (e.g., polio)
- Dawn syndrome
- Occasional coexistence of Sjogren syndrome or autoimmune thyroid disease
Mallory-Weiss tears
mucosal tears near the gastroesophageal junction
- Most often associated with severe retching or vomiting secondary to acute alcohol
intoxication
