Esophagus Flashcards
Atresia and fistulae
structral developmental anomalies that disrupt normal gastrointestinal transit and typically present early in life
imperforate anus
the most common form of congenital intestinal atresia, while the esophagus is the most common site of fistulization
Stenosis
may be developmental or acquired. Both forms are characterized by a thickened wall and partial or complete luminal obstruction. Acquired forms are often due to inflammatory scarring
Diaphragmatic hernia
is characterized by incomplete diaphragm development and herniation of abdominal organs into the thorax. This often results in pulmonary hypoplasia.
omphalocele and gastroschisis
refer to ventral herniation of abdominal organs
ectopia
refers to the presence of normally formed tissues in an abnormal site.
ectopic gastic mucosa
common in the upper third of the esophagus
meckel diverticulum
presence of all three layers of the bowel wall reflecting failed involution of the vitelline duct. It is common and is a frequent site of gastric ectopia, which may result in occult bleeding
congenital hypertrophic pyloric stenosis
a form of obstruction that presents between the third and sixth weeks of life. There is an ill-defined genetic component to this disease, which is most common in males.
Hirschsprung disease
caused by the absence of neural crest derived ganglion cells within the colon. It causes functional obstruction of the affected bowel and proximal dilation. Theh defect always begins at the rectum, but extends proximally for variable lengths.
Most common type of tracheoesophageal fistula
blind upper segment with fistula between the lower segment and trachea
Nutcracker esophagus
describes patients with high-amplitude contractions of the distal esophagus that are, in part, due to loss of the normal coordination of inner circular layer and outer longitudinal layer smooth muscle contractions.
Diffuse esophageal spasm
is characterized by repetitive, simultaneous contractions of the distal esophageal smooth muscle.
hypertensive lower esophageal sphincter.
Lower esophageal sphincter dysfunction, such as high resting pressure or incomplete relaxation, are present in many patients with nutcracker esophagus or diffuse esophageal spasm. In the absence altered patterns of esophageal contraction, these sphincter abnormalities are termed * hypertensive LES
Esophageal Obstruction
Because wall stress is increased, esophageal dysmotility may result in development of small diverticulae, primarily the epiphrenic diverticulum located immediately above the lower esophageal sphincter.
Zenker diverticulum
impaired relaxation and spasm of the cricopharyngeus muscle after swallowing can result in increased pressure within the distal pharynx and development of a Zenker diverticulum (pharyngoesophageal diverticulum), which is located immediately above the upper esophageal sphincter.
Zenker diverticulae are uncommon, but typically develop after age 50 and may reach several centimeters in size. When small they may be asymptomatic, but larger Zenker diverticulae may accumulate significant amounts of food, producing a mass and symptoms that include regurgitation and halitosis
Esophageal mucosal webs
Paterson-Brown-Kelly or Plummer-Vinson syndrome
Schatzki rings: A rings and are covered by squamous mucosa; in contrast, those located at the squamocolumnar junction of the lower esophagus are designated B rings and may have gastric cardia-type mucosa on their undersurface
Achalasia
Achalasia is characterized by the triad of incomplete LES relaxation, increased LES tone, and aperistalsis of the esophagus
Symptoms include dysphagia for solids and liquids, difficulty in belching, and chest pain
Primary achalasia
is the result of distal esophageal inhibitory neuronal, that is, ganglion cell, degeneration
Secondary achalasia
may arise in Chagas disease, in which Trypanosoma cruzi infection causes destruction of the myenteric plexus, failure of peristalsis, and esophageal dilatation
Mallory-Weiss tears
Longitudinal mucosal tears near the gastroesophageal junction are termed Mallory-Weiss tears, and are most often associated with severe retching or vomiting secondary to acute alcohol intoxication
Boerhaave syndrome
esophageal rupture
can come from trauma or cancer, e.g.
Chemical and Infectious Esophagitis
The stratified squamous mucosa of the esophagus may be damaged by a variety of irritants including alcohol, corrosive acids or alkalis, excessively hot fluids, and heavy smoking
GERD
LES is not working properly
inflammation from the reflux
GERD is most common in individuals older than age 40 but also occurs in infants and children.
The most frequent clinical symptoms are heartburn, dysphagia, and regurgitation of sour-tasting gastric contents. Rarely, chronic GERD is punctuated by attacks of severe chest pain that may be mistaken for heart disease.
Treatment with proton pump inhibitors, which have replaced H2 histamine receptor antagonists, to reduce gastric acidity typically provides symptomatic relief
Hiatal hernia
can give rise to symptoms, such as heartburn and regurgitation of gastric juices, that are similar to those of GERD. It is characterized by separation of the diaphragmatic crura and protrusion of the stomach into the thorax through the resulting gap
Eosinophilic Esophagitis
The majority of individuals with eosinophilic esophagitis are atopic and many have atopic dermatitis, allergic rhinitis, asthma, or modest peripheral eosinophilia.
Treatments include dietary restrictions to prevent exposure to food allergens, such as cow’s milk and soy products, and topical or systemic corticosteroids
Esophageal Varices
Portal hypertension results in the development of collateral channels at sites where the portal and caval systems communicate
–> esophageal varices
and huge hemorrhoids
and caput medusa
clinical features of gastroesophageal varices
are present in nearly half of the patients with cirrhosis, and 25-40% of patients with cirrhosis develop variceal bleeding.
Approximately 12% of previously asymptomatic varices bleed each year. Variceal hemorrhage is an emergency that can be treated medically by inducing splanchnic vasoconstriction or endoscopically by sclerotherapy (injection of thrombotic agents), balloon tamponade, or variceal ligation.
Despite these interventions, 30% or more of patients with variceal hemorrhage die as a direct consequence of hemorrhage such as hypovolemic shock, hepatic coma, or other complications. Furthermore, more than 50% of patients who survive a first variceal bleed have recurrent hemorrhage within 1 year, and this carries a mortality rate similar to that of the first episode
Barrett Esophagus
Barrett esophagus is a complication of chronic GERD that is characterized by intestinal metaplasia within the esophageal squamous mucosa
The greatest concern in Barrett esophagus is that it confers an increased risk of esophageal adenocarcinoma
**
clinical features of barrett esophagus
can only be identified thorough endoscopy and biopsy, which are usually prompted by GERD symptoms
Intramucosal or invasive carcinoma requires therapeutic intervention. Treatment options include surgical resection, or esophagectomy, as well as newer modalities such as photodynamic therapy, laser ablation, and endoscopic mucosectomy
Multifocal high-grade dysplasia, which carries a significant risk of progression to intramucosal or invasive carcinoma, is treated as intramucosal carcinoma. Many physicians follow low-grade dysplasia or a single focus of high-grade dysplasia with endoscopy and biopsy at frequent intervals.
Esophageal Tumors
The vast majority of esophageal cancers fall into one of two types, adenocarcinoma and squamous cell carcinoma
Most esophageal adenocarcinomas arise
from Barrett esophagus
Adenocarcinoma
Molecular studies suggest that the progression of Barrett esophagus to adenocarcinoma occurs over an extended period through the stepwise acquisition of genetic and epigenetic changes
Chromosomal abnormalities, mutation of *TP53, and downregulation of the cyclin-dependent kinase inhibitor *CDKN2A, also known as * p16/INK4a, are detected at early stages.
In the case of CDKN2A, both allelic loss and hypermethylation-induced epigenetic silencing have been described. Later during progression there is amplification of *EGFR, ERBB2, MET, cyclin D1, and cyclin E genes.**
lower esophageal tumor more likely to be an
adenocarcinoma
a mid-to upper- 1/3 lesion on the esophagus is more likely to be a
squamous cell
clincial features of adenocarcinomas
Although esophageal adenocarcinomas are occasionally discovered in evaluation of GERD or surveillance of Barrett esophagus, they more commonly present with pain or difficulty in swallowing, progressive weight loss, hematemesis, chest pain, or vomiting.
By the time symptoms appear, the tumor has usually spread to submucosal lymphatic vessels. As a result of the advanced stage at diagnosis, overall 5-year survival is less than 25%.
In contrast, 5-year survival approximates 80% in the few patients with adenocarcinoma limited to the mucosa or submucosa
Squamous Cell Carcinoma
Risk factors include alcohol and tobacco use, poverty, caustic esophageal injury, achalasia, tylosis, Plummer-Vinson syndrome, diets that are deficient in fruits or vegetables, and frequent consumption of very hot beverages
Clinical Features
of squamous cell carcinomas
The onset of esophageal squamous cell carcinoma is insidious and it most commonly presents with dysphagia, odynophagia (pain on swallowing), or obstruction. Patients subconsciously adjust to the progressively increasing obstruction by altering their diet from solid to liquid foods. Prominent weight loss and debilitation result from both impaired nutrition and effects of the tumor itself
Increased prevalence of endoscopic screening has led to earlier detection of esophageal squamous cell carcinoma. This is critical, because 5-year survival rates are 75% in individuals with superficial esophageal squamous cell carcinoma but much lower in patients with more advanced tumors.
Lymph node metastases, which are common, are associated with poor prognosis. The overall 5-year survival rate in the United States remains less than 20%
