Lecture 2: Esophagus

Lower Esophageal Sphincter (LES)

Internal LES (thickened muscularis propria) + External LES (diaphragm muscle attached by ligaments) anchored together by phrenoesophageal ligament

LES is normally closed (is an antireflux barrier protecting the esophagus from the caustic gastric content)

During swallowing or belching, the LES muscle must relax briefly to allow passage of food or intra-gastric air

Dysphagia

difficulty, discomfort, or sensation of food getting stuck in the throat or chest when swallowing

Odynophagia

pain while swallowing

Esophageal Webs

Intraluminal semi-circumferential protrusion of a thin fold of mucosa (mucosa + submucosa)

Women > 40

Usually in upper esophagus

Plummer-Vinson syndrome: Dysphagia due to Esophageal Web & Iron deficiency anemia

PVS considered a risk factor for development of Squamous Carcinoma of Pharynx & Esophagus

Schatzki Ring

Circumferential & thicker (includes submucosa or muscularis propria)

Usually occur in distal esophagus (immediately above or below the Squamocolumnar junction)

asymptomatic or cause sporadic dysphagia

Obstruction of esophagus by a bolus of food → crushing chest pain

Schatzki Ring

Achalasia

Failure of LES to relax (open) after swallowing + lack of coordinated esophageal peristalsis

Due to selective degeneration or damage to the parasympathetic post-ganglionic neurons that relax the lower sphincter & are responsible for peristalsis

Primary: Idiopathic (most common); incidence ↑ with age

Secondary: Acquired: Chagas Disease (T. Cruzi), Diabetic Autonomic Neuropathy, Amyloidosis, Cancer

Triple-A (Achalasia-Addisonianism-Alacrima)/Allgrove syndrome: Achalasia, Adrenal insufficiency & lack of tear production

Dysphagia to solids & liquids, regurgitation of undigested food, chest pain, aspiration pneumonia

Cancer risk for both esophageal Squamous & Adenocarcinoma

Beak sign on Barium swallow with mega-esophagus

Achalasia

Diffuse/Distal Esophageal Spasm (DES)

Strong, repetitive, simultaneous contractions (non-sequential pressure peaks) of distal esophagus → intermittent dysphagia & atypical chest pain

Nutcracker Esophagus

Increased pressures during peristalsis

Manometry when pressures exceed 180 mmHg

May cause chest pain, dysphagia or be asymptomatic

Hypertensive LES

like Achalasia, but with normal peristalsis (incomplete relaxation confined to sphincter)

Hypotensive LES

GERD

Resting LES pressure <10 mmHg

Esophageal Diverticula

Most are acquired Pseudodiverticula (herniations of mucosa only) associated with dysmotility

Increased intraluminal pressures & wall stress from the dysmotility syndromes may cause pulsion type Diverticula

Right above the LES (Epinephric Diverticulum)

Impaired relaxation & spasm of Cricopharyngeal muscle after swallowing → Pharyngoesophageal Diverticulum (Zenker)

Zenker → Dysphagia & sense of a lump in the throat; food trapping leads to regurgitation of food, chronic cough; Halitosis; Infection

Zenker Diverticulum

Epinephric Diverticulum

Mallory-Weiss Syndrome

Superficial esophageal tears

Longitudinal mucosal tears, usually near or across GE junction, most often due to retching (dry heaves) or vomiting from acute alcohol intoxication

Painful hematemesis

Boerhaave syndrome

Transmural perforation/Effort rupture

Perforation due to vomiting, but majority of esophageal perforations are Iatrogenic

Rupture of distal esophagus → Mediastinitis

Leakage of esophageal & gastric contents into the mediastinum, produces a chemical burn with superinfection

Untreated, leads to a severe inflammatory response, sepsis & death

Follows repeated episodes of retching & vomiting

Usually no hematemesis; excruciating retrosternal chest & upper abdominal pain

Odynophagia, tachypnea, dyspnea, cyanosis, fever, & shock develop rapidly

May see air in mediastinum and/or subcutaneous emphysema

Esophagitis

erosion, ulceration, bleeding, or scar/fibrosis (stricture) formation with stenosis

Odynophagia

Gastroesophageal Reflux Disease (GERD)

Reflux Esophagitis

reflux of gastric acid/contents back into the esophagus due to ↓ LES tone or LES incompetence or due to ↑ intra-abdominal pressure

Heartburn (burning sensation rising from the stomach into the chest & neck or regurgitation of sour tasting gastric contents), often worse immediately after eating and/or lying down

Risk factors include alcohol, tobacco, obesity, hiatal hernia, large meals, age >50; bending over or coughing exacerbate

Mild: normal or redness of mucosa due to hyperemia

Severe: Squamous Epithelial hyperplasia + intra-epithelial Eosinophils

Complications of severe long-standing GERD: ulceration with hematemesis or melena, stricture, Barrett’s Esophagus

PPI

Infectious Esophagitis

Immunosuppressed

Herpes, CMV & Candida are AIDS indicators

Eosinophilic Esophagitis

eosinophilic microabscesses

Eosinophilic Esophagitis

Adults: Dysphagia, odynophagia

Children: feeding intolerance

due to food allergy

most often in Atopic individuals (atopic dermatitis, allergic rhinitis, asthma, eosinophilia)

Concentric rings (trachealization)

Morphology: large numbers of eosinophils or eosinophilic microabscesses in epithelium

Esophageal Varices

abnormally dilated vein

Portal hypertension is commonly caused by Cirrhosis of the Liver

patients may exsanguinate into their GI tract

Barrett Esophagus

Metaplasia in the lower esophagus from squamous to intestinal type mucosa with goblet cells

Acid backwash into the esophagus (symptons of GERD) predisposes for Barrett’s

Increased RISK for the development of Esophageal Adenocarcinoma

Risk is significant if “pre-cancerous” Dysplasia is present

Barrett Esophagus

Esophageal Adenocarcinoma

Most are felt to arise from the intestinal metaplastic mucosa of Barrett esophagus

Same risk factors: GERD, male, Caucasian race, obesity, smoking, alcohol

involves Distal 1/3 of esophagus and/or Gastric Cardia/Esophagogastric Junction (if upper edge of the tumor extends to the Esophagus)

Progressive dysphagia (solids → liquids), weight loss, hematemesis, chest pain, vomiting

Squamous Carcinoma

Risk factors: older, male, African-American, alcohol & tobacco, caustic esophageal injury, Achalasia, Plummer-Vinson syndrome, very hot beverages, mediastinum radiation, diet low in fruits & vegetables

Tylosis, familial mutation; hyperkeratosis of palms, soles & oral leukoplakia; high lifetime risk; loss of tumor suppressor gene TEC (Tylosis with Esophageal Cancer)

Half occur in the middle third of the esophagus

Progressive dysphagia, odynophagia, weight loss

Arise from squamous dysplasia

Squamous Carcinoma

Adenocarcinoma: Abortive Glands with mucin

Squamous: squamous pearls

Esophageal Atresia & Tracheoesophageal Fistulae

Atresia or fistula with blind upper segment → regurgitation after feeding

Fistulas → aspiration pneumonia or suffocation by aspirated food

Discovered shortly after birth with first feedings → coughing, choking, vomiting, difficulty breathing, or cyanosis during feeding

Esophageal Obstruction

mechanical cause: stenosis due to tumor, stricture (inflammatory scarring), web

functional cause: disruption of the coordinated waves of contraction (Peristalsis) or failure of LES relaxation that follows swallowing (Achalasia)

Dysphagia, odynophagia, Bringing food back up (regurgitation), coughing or gagging when swallowing or having to cut food into smaller pieces

Mechanical obstruction is more likely to present with Progressive Dysphagia (begins with inability to swallow solids, slowly progressing to difficulty ingesting liquids)