Esophageal Disorders Flashcards
What is the function of the esophagus?
to transport the bolus from pharynx into the gastric reservoir
Which portion of swallowing is voluntary? involuntary?
the inital phase is voluntary but as bolus is pushed backward by the tongue to the hypopharynx the involuntary phase of swallow reflex is triggered
How is the larynx elevated during the initial phase of swallowing?
suprathyroid muscles pull thyroid/cricoid up, epiglottis gloses off glottis
What type of muscle is the UES? LES?
UES-skeletal
LES-smooth
What is the role of the LES?
prevents reflux of acid with it’s tone
reenforced by crural diaphragm
How is the bolus moved from mouth to stomach?
ante-grade peristalsis (coordinated and propulsive sequential contraction)
primary peristalsis occurs in concert with appropriately timed relaxation of the sphincters
What is primary peristalsis?
triggered by swallow
associated with pharyngeal contraction and UES relaxtion
What is secondary peristalsis?
triggered by esophageal peristalsis
contraction start proximal to distention
What are the 2 innervations of the esophagus that generate peristalsis?
intrinsic-enteric neural plexus
extrinsic-vagus nerve
What 2 nuclei are involved in neural control of peristalsis?
nucleus ambiguous-proximal esoph.
dorsal motor nuclei-distal esoph.
What generates the sequence of peristalsis?
central pattern generator of the brainstem
How is peristalsis in smooth muscle regulated physiologically?
as a wave of inhibition followed by a wave of excitation
What is the main excitatory neurotransmitter?
acetylcholine
What is the main inhibitory neurotransmitter?
nitric oxide
What is dysphagia?
difficulty to eat (during swallow)
sticks, caught, hung up
NOT like globus sensation (always a lump in the throat)
3 main questions to ask with dysphagia history
1: what kind of food
2: intermittent or progressive
3: other symptoms (heart burn, regurg, odynophagia, chest pain)
Main features of esophageal dysphasia
sticks/hang ups after swallow
may have chest pain or not
pain can refer to pharynx
Main features of pharyngeal dysphagia
difficulty initiating swallow
coughing, choking, nasal regurgitation
canNOT refer to esophagus
3 main mechanical dysphagias
peptic stricture
esophageal ring
cancer
3 main neuromuscular dysphagias
achalasia
esophageal spasm
dysmotility
What type of dysphagia casues problems with solid food only?
mechanical obstruction
What type of dysphagia causes problem with solid or liquid food?
neurouscular
3 main features of mechanical obstruction
progressive (age >50 cancer) chronic heartbutn (peptic stricture) intermittent (esophageal ring)
2 main features of neuromuscular dysphagia
progressive with hearburn/regurg-scleroderma
intermittent and chest pain-spasm
What are the techniques used to diagnose esophageal disorders?
upper gi endoscopy
esophageal manometry
radiography/esophagram
What is the Z line?
GEJ opening
How does esophageal manometry work?
measures esophageal intra-luminal pressures
What are the steps of primary peristalsis in the esophagus?
UES relaxes .5s
primary peristaltic wave produces a lumen-occluding contraction with amplitude of 30-150mm HG
Peristlatic duration 3-7s, migrates aborally at a speed of 3-5cm/s
LES relaxes 3-8 s to allow bolus emptying into stomach
What is achalasia?
impaired LES relaxation/increased LES tone
loss of peristalsis in the body of the esphagus
due to impared and then loss of inhibitory (NO) activity
Presentation of achalasia?
dysphagia ~90%
chest pain, heartburn, regurg, wt loss ~60%
What accomodative behaviors do people with achalasia
slow, stereotypical eating movements
avoiding social events with meals
What are the characteristic radiographic findings of achalasia?
bird beak sign sigmoid shape (end stage)
What else does the differential diagnosis for achalasia contain?
malignancy other infiltrative disorders chagas disease paraneoplastic syndromes autonomic nerve damage
What are the treatments for achalasia?
NO donors/anticholinergic agents
endoscoptic therapy: botulinum toxin injection (inhibits Ach release), pneumatic dilation
operative therapy
Define esophageal spasm
dyscoordinated contraction, usually in body, LES usually fine
intermittant, problems with liquids
Describe complete aperistalsis/scleroderma esophagus
smooth muscle contraction lost, skeletal muscle still works
also seen w/polio, severe COPD & severe diabetes
What is stratified squamous non-keratinized stratified epithelium resistant to? sensitive to?
reistant to: abrasion
Sensitive to: acid
What makes up the pre-epithelial defense?
mucus-unstirred water layer-bicarbonate barrier
mucus blocks pepsin but not hydrogen ions
What makes up the epithelial defense?
apical cell membrane, intercellular junctional complex
intracellular buffering and H+ extrusion processes
What is the pathophysiology of GERD?
decreased in normally constant LES tone
reflux of gastric juices leading to mucosal injury
IL-6 production–>more H2O2 in muscle–>increase in PAF and PGE2–>decreased ACh release and LES tone
What can lead to an incompetent LES? (3)
transient LES strain
strain
hypotonic LES
What causes a hiatal hernia?
separation of diaphragmatic crura and LES
What are the two types of hiatal hernia?
sliding/type I-common, asymptomatic usually
paraesophageal/type II
What is characteristic histologically of reflux?
> 20% of total epithelium basal zone epithelium (normal 10%)
eosinophils are recruited into the squamous mucosa, followed by neutrophils (more severe)
What may be seen on endoscopy in a person with GERD?
redness, erosions
What is the most common cause of esophagitis?
reflux of gastricc contents (reflux esophagitis)
What are classic symptoms of reflux esophagitis?
heartburn
regurgitation
(atypical chest pain, chronic cough, hoarseness also possible)
What diagnostic modalities are used for GERD?
endoscopy-more specific
ambulatory reflux monitoring-more sensitive
radiography
What are the “alarm” symptoms of GERD?
dysphagia anemia weight loss abdominal mass vomiting
How is GERD managed?
lifestyle modifications (wt loss, elevation of bed, avoiding late meals & trigger foods) pharm (PPIs, anti-secretory drugs) Operative (fundoplication, substitute devices to enforce LES)
What are the major complications of GERD?
**Barrett’s esophagus
esophageal ulcer, stricture, bleeding
What are the most common causes of esophageal stricture?
chronic GERD
radiation
caustic injury
(inflammation and scarring)
Features of esophageal stricture
difficult eating solids first, then liquids
fibrous thickening of submucosa
atrophy of muscularis propria
secondary epithelial damage
What is eosinophilic esophagitis?
epithelial infiltration by large numbers of eosinophils, particularly superficially
if far from GEJ can differentiate from GERD
Clinical presentation of eosinophilic esophagitis?
Adults: dysphagia, most common cause of food impaction, heartburn, nausea
Kids: nausea, burning, food intolerance
failure of acid suppressive treatment & absence of acid reflux
What family history information may be pertinent to eosinophilic esophagitis?
personal/family history of atopia (atopic dermatitis, rhinitis, asthma)
What causes eosinophilic esophagitis?
allergic immune reactions to ingested/inhaled allergens that invovles Tcell mediated HSR
eosinophil activation/infiltration
major basic protein, increased IL5 & IL13
tissue remodeling/fibrosis, change in mechanical properties of the esophagus
What confirms a diagnosis of eosinophilic esophagitis?
> 15 eosinophils/HPF in esophageal mucosa
history of food impaction also extremely important
What is the treatment for eosinophilic esophagitis?
elimination diet
topical steroids
systemic steroids
endoscopic dilation
Features of chemical esophagitis
irritants
medicinal pills may lodge and dissolve in esophagus
self-limited pain, odynophagia
Who usually gets infectious esophagitis?
immunosuppressed/debilitated
overall very rare
What are the most common causes of viral esophagitis?
HSV
CMV
Key features of HSV esophagitis?
punched out ulcers
nuclear inclusions, multinucleate cells
Key features of CMV esophagitis?
shallow ulcerations
cytoplasmic and nuclear inclusions
Most common cause of fungal esophagitis?
candida (mucormycosis & aspergillosis also possible)
gray/white pseudomembranes
How common is bacterial esophagitis?
10% infectious esophagitis
What are the main causes of Iastrogenic esophagitis?
chemo
GVHD (very rare)
radiation-due to blood vessel thickening/ischemic injury
What skin disorders are commonly associated with esophagitis?
bullous pemphigoid & epidermolysis bullosa (desquamative skin disease)
lichen planus
crohn’s disease
What is Barrett’s esophagus?
squamous epithelium replaced by metaplastic columnar mucosa w/goblet cells (intestinal)
incidence increasing
What can cause barrett’s esophagus?
chronic GERD (10% of GERD pts have)
How often does epithelial dysplasia develop from BE?
.2-1% pts w/BE/yr
Is barrett’s esophagus symptomatic?
NO
What genes likely play a role in BE?
Cdx-expressed in 100% of BE
p53, Cyclin D1 later carcinogenesis
What defines adenocarcinoma?
intramucosal carcinoma is characterized by invasion of neoplastic epithelial cells into the lamina propria
What is the morphology of BE?
tongues/patches of red velvety mucosa extending upward from the GEJ, alternates with normal esophageal mucosa
How does BE present?
endoscopic & histologic evidence of metaplasia
white adult male bwn 40-60 w/long term reflux sx
asymptomatic most often
What do you do about BE?
periodic endoscopy with biopsy
What are the risk factors of esophageal adenocarcinoma?
western countries dysplasia in BE tobacco obesity radiation therapy
Who usually gets esophageal adenocarcinoma?
white middle aged men
How does adenocarcinoma present?
dysphagia odynophagia progressive wt loss vomiting found during BE surviellance
What is the survival rate for adenocarcinoma?
5yr sruvival 80% if only superficial
<25% 5yr survival overall due to advanced age at time of dx
What genes are associated with adenocarcinoma?
chromosomal abnormalities p53 cyclin D1, cyclin E c-ERB-B2 increased expression of TNF and NFKB (suggests chronic inflammation contributes)
What is the morphology of adenocarcinoma?
flat or raised patches in otherwise intact mucosa
usually DISTAL 1/3, may invade gastric cardia
tumors typically produce mucin and form dense glands
What is the common presentation of squamous cell carcinoma of the esophagus?
african american male adults older than 45 yo
What are risk factors for SCC?
alcohol tobacco poverty caustic injury achalasia/plumer-vinson syndrome frequent consumption of hot beverages radiation therapy
What coutnries have the highest incidence of SCC?
iran, turkmenistan, china, hong kong, argentina, brazil, south africa
What SCC risk factors are found in endemic regions?
nutritional deficiencies mutagenic compounds (in fungus contaminated food) HPV infection
What is the morphology of SCC of hte esophagus?
MIDDLE 1/3 of esophagus
small, grey plaque like thickenings
lead to tumor masses that protrude into and obstruct the lumen
may invade respiratory tree or aorta
usually moderately to well differentiated
What are the main symptoms of SCC?
usually large at time of DX dysphagia odynophagia obstruction first sx may be caused by aspiration of food through a TE fistula
What does detection of esophageal tumors occur so late?
patients may adjust by altering their diet from solid to liquid foods
Why does extreme wt loss and debilitation occur during SCC?
impaired nutrition and effects of tumor itself
What is the survival rate for SCC?
75% 5yr survival if superficial
overall 5yr survival <9% due to late detection
lymph node involvement-poorer prognosis
Which lymph nodes are associated with the upper 1/3 of the esophagus?
cervical
Which lymph nodes are associated with the middle 1/3 of the esophagus?
mediastinal, paratracheal, tracheobronchial
Which lymph nodes are assoicated with the lower 1/3 of the esophagus?
gastric and celiac nodes
