Pathophysiology of the Esophagus Flashcards
Dysphagia
difficulty swallowing
2x2 table:
obstructive & propulsive/motility
x
oropharyngeal & esophageal
oropharynx
entrance to gut
- teeth/lips: biting and grinding
- mastication/saliva: conversion of bite into small, soft, lubricated bolus
- tongue: pushes bolus into pharynx
- pharynx: movement of bolus from mouth to upper esophagus
- protection of airway and nasal passages
Deglutition (swallowing)
- closure of nasopharynx via elevation of the soft palate
- elevation of posterior tongue
- epiglottis and vocal cord closure
- bolus movemnt and nose/airway closure
normal: 600x/d
oral phase: voluntary
Pharyngeal phase: involuntary (begins with bolus on posterior tongue and upper pharynx)
oropharyngeal dysfunction
oropharyngeal dysphagia
inability to initiate a swallow or transfer food bolus to esophagus
-may occur w/ obstruction or neuromuscular disease (leads to dysfunction of oropharyngeal musculature: propulsive/motility disorder)
- Nasal regurgitation may occur
- Aspiration= food or liquids passing into airway or lungs (cough after attempted swallows; airway obstruction– choking, stridor, wheezing, cyanosis; aspiration pneumonitis = lung injury from acidic or lipophillic properties of food– SOB or hypoxia; pneumonia if bacterial colonization occurs– SOB, fever, white count, consolidation on CXR)
Neurologic oropharyngeal diseases
stroke ALS Parkinson's MS Polio
Muscular oropharyngeal diseases
Myasthenia gravis
Muscular dystrophy
Muscular injury (surgery, radiation therapy)
Benign structural oropharyngeal diseases
Zenker’s diverticulum: outpouching of esophagus leading to food regurgitation or bacterial colonization (halitosis)
- Crycopharyngeal bar
- thyromegaly, fibrosis (eg radiation)
Malignant structural oropharyngeal disease
squamous cell carcinoma of tongue, oropharynx, soft palate, or upper larynx (Head and neck cancers)
Oropharyngeal Disease dx
History
PE
(Modified) barium swallow– XR (video) of mouth and throat under direct observation while pt chews and swallows various consistencies of radio-opaque barium
?neurology consultation for tx
Oropharyngeal disease tx
- mod of diet
- radiation or surgical resection for tumor, ring, or diverticulum
- speech/PT– cornerstone of tx for neuromuscular disease
- percutaneous endoscopic gastrostomy (PEG) tube may be needed for feeding and preventing aspiration
Table: Box 1: obstructive x oropharyngeal
Head and neck cancers
Zenker’s diverticulum
radiation therapy
Table: Box 2: propulsive/motility x oropharyngeal
-Neurologic conditions: stroke ALS MS Parkinsons -Myasthenia gravis -muscular dystrophy
Esophagus
transport: conduit for food/water from oropharynx to stomach
barrier: protection of mediastinum and lungs from ingested food/water
1 way system: prevention of reflux of gastric contents into pharynx or airway
Motility Disorders of esophagus: sx, etiology, dx
Sx: dysphagia to BOTH solids and liquids; chest pain
Etiology: achalasia: abnormal peristalsis, failure of LES relaxation spastic disorders of esophagus weak peristalsis scleroderma
Dx:
- exclude structural lesion (upper endoscopy or barium esophagram)
- esophageal manometry
Achalasia
“no relaxation”
- most imp motility disorder of esophagus
- impaired relaxation of lower esophageal sphincter
- absence of normal peristalsis
- idiopathic
- both genders, all races, adults (25-60)
Sx of achalasia
- dysphagia to solids and liquids
- weight loss
- regurgitation
- chest pain
- difficulty belching
- heartburn
- hiccups
Type I Achalasia (manometry)
Type I (Classic) -swallowing--> no significant change in esophageal pressurization
Type II Achalasia manometry findings
Swallowing–> simultaneous pressurization spanning entire esophagus length
-botox injections, pneumatic dilation, surgical myotomy work best
Type III (Spastic) Achalasia manometry findings
Swallowing–>abnormal, lumen obliterating contractions/spasms
botox injections, pneumatic dilation, surgical myotomy have POOR outcomes
Pathophysiology of Achalasia
-Normal: LES pressure and relaxation regulated by excitatory and inhibitory neurotransmitters
Selective loss of inhibitory neurons in the myenteric plexus resulting in relatively unopposed excitatory (cholinergic) neurons–> hypertensive nonrelaxed esophageal sphincter
Vast majority of achalasias
Primary (idiopathic)
Secondary (pseudoachalasia)
- T cells, Ab attacking neurons of myenteric plexus)
Chagas disease
Tx for Achalasia
-Medical therapy (if contraindications to dilation or surgery):
Nitrates
Calcium channel blockers
Sildenafil
Endoscopic therapy:
GE Junction botox injections
Pneumatic balloon dilation – tear LES fibers (SE: perforation, heartburn); 40-95% remission 12 mo
POEM– per-oral endoscopic myotomy
Surgical (Heller) myotomy
-usually laparscopic
-70 to 85% remission @ 10 y
Complications: reflux, perforation
Scleroderma/Progressive Systemic Sclerosis (PSS)
Multisystem disorder charac by:
- Obliterative small vessel vasculitis
- Connective tissue proliferation with fibrosis of multiple organs
GI manifestations in 80-90%
The principal pathological abnormalities (GI): smooth muscle atrophy and gut wall fibrosis.
Smooth Muscle atrophy and gut wall fibrosis in scleroderma/PSS
Myopathic (predominantly) process
- Esophageal Manifestations?
- Smooth Muscle Atrophy–> Weak Peristalsis –> Dyspahgia
- Smooth Muscle Atrophy –> Weak LES –> GERD
- Unrepentant GERD –> Esophagitis –>Stricture
- Esophageal manometry
Spastic Disorders of the Esophagus
Conditions of uncertain etiology
Peristalsis preserved
Symptoms usually chest pain and dysphagia
Postulated pathophysiology: overactivity of excitatory nerves or overreactivity of the smooth muscle response
Tx: limited.
meds: CCBs, sildenafil
Botox
?POEM
Table: Box 4: Propulsive/motility x esophageal
Achalasia
- scleroderma
- spastic disorders (Jackhammer pattern)
Structural disorders of esophagus (sx)
-luminal narrowing/obstruction
sx:
dysphagia to solids (liquids much LATER)
-weight loss (ominous)
-heartburn (sometimes)
Benign Structural esophageal disorders
strictures
- GERD related
- Caustic (medication or ingestion)
Schatzki’s ring
Eosinophilic esophagitis (EoE)***
Extrinsic compression
Malignant structural esophageal disorders
-Esophageal cancer (can stricture):
adenocarcinoma
squamous cell cancer
-Metastasis (rare) melanoma breast cancer renal cell carcinoma lung cancer
-direct invasion
esophageal strictures
benign or malignant -cardinal sx: **dysphagia to solids -characterized by: Painless solids sx usally on regular or daily basis may be progressive, esp w/ cancer weight loss (ominous)
Benign esophageal stricture
Causes: GERD, radiation, caustic ingestion (including medications), congenital
Rule out cancer with biopsy during EGD
Treatment = endoscopic dilation using balloons or sequential commercial dilators
Malignant esophageal stricture
SCC
adenocarcinoma
Eosinophilic Esophagitis (EoE)
Chronic immune/antigen-mediated esophageal disease
Clinicopathologic diagnosis:
Symptoms of esophageal dysfunction
Eosinophilic infiltrate in the esophagus
Absence of other potential causes of esophageal eosinophilia
Clinical features: adults/adolescents: dysphagia (25-100%) -~50 of cases of acute food impaction -food avoidance -maybe heartburn
in children: more non-specific (feeding intolerance, failure to thrive, abdominal pain)
Demographics of EoE
most common
EoE Tx
3 Ds
drugs (steroids– topical»_space;> systemic; asthma preparations that are swallowed)
diet (elemental diet– allergen free effective in kids; most practical: 6 food elimination diet SFED– milk, eggs, wheat, soy, seafood, nuts)
dilation
Table: Box 3: obstructive x esophageal
esophageal strictures
esophageal rings
EoE*
extrinsic compression
GERD
- pathologic reflux of gastric juice (acid) into esophagus
- common
- causes symptoms, esophageal injury, or increased cancer risk
GERD classic sx
Heartburn: often post-prandial, may be positional (lying down/nocturnal)
regurgitation with acidic taste (Also positional)
less classic sx:
water brash, throat clearing, cough
Rare: wheezing, stridor, hoarseness
Relieved by antacids or anti-secretory medications
GERD Pathophysiology
Acid in the esophagus or airway –> symptoms and/or esophageal damage
Esophagus lacks defenses (mucous secretion, alkalinity) against acid
Inappropriate LES relaxation
Hiatal hernia
Gastric or esophageal surgery, dysmotility, or obstruction
Rare: Zollinger-Ellison, Sjogren’s, Scleroderma
GERD RFs
Males = females Obesity Caffeine? Not really Alcohol? Minimally if at all Tobacco Medications Pregnancy Other medical illnesses (scleroderma, ZE, gastroparesis)
GERD complications
normal >80%
erosive esophagitis 5-10%
Barrett’s 5%
GERD Dx
Usually by symptoms (Heartburn +/- Regurgitation)
Response to acid suppressive therapy (proton pump inhibitors)
Endoscopy usually for refractory symptoms but vast majority normal
Can use ambulatory pH testing; transnasal catheter or wireless capsule
rates of healing erosive esophagitis w/ PPIs 80-95%
Barrett’s Esophagus
consequence of GERD
RFs:
- male
- white
- central adiposity
- advancing age (plateau in 60s)
- Chronic GERD
- *Increased risk of developing esophageal adenocarcinoma (0.1-0.5% per year)
- endoscopy w/ biopsies every 3-5 years to assess for dysplasia
Look for dysplasia
- if present: higher cancer risk
- low grade: close surveillance
- high grade: treatment
Treatment of Barrett’s
Esophagectomy: previously for HGD or any cancer
***Endoscopic Treatment (ablation of Barrett’s tissue, endoscopic resection of visible lesions): Now for HGD and early esophageal adenocarcinomas
Esophageal cancer
- progressive dysphagia (solids to liquids)
- weight loss
- rare: hemoptysis, chest pain, anemia
- Causes symptoms when ADVANCED
- Tx:
- surg resection if caught early
- most: chemo/rad in advanced cases
- Metal stent or feeding tube for palliation
Squamous cell carcinoma
(esophageal cancer)
- RF: older age, alcohol/tobacco use, caustic injuries
- can arise anywhere in esophagus
- declining incidence in US/Eur
Adenocarcinoma
RFs: older age, smoking, obesity, GERD, and ***Barrett’s esophagus
- rising incidence in US and Eur
- nearly always in distal esophagus or gastric cardia
Dysphagia Obstructive oropharyngeal
Choking
Cough
Nasal regurgitation
Aspiration
Head and Neck Cancers
Zenker’s Diverticulum
Radiation Therapy
Eval:
barium swallow
dysphagia, causes, eval: propulsive/motility oropharyngeal
Transfer Dysphagia
Cough
Nasal regurgitation
Aspiration
Neurologic Conditions Stroke ALS MS Parkinson’s Myasthenis Gravis Muscular Dystrophy
eval:
barium swallow
dysphagia, causes, eval: obstructive esophageal
Dysphagia to solids Food impaction (EoE) Weight loss Vomiting Regurgitation
Esophageal Strictures Esophageal Rings EoE Extrinsic Compression Esophageal Cancer
eval:
EGD
esophagram
Dysphagia causes, eval: propulsive/motility and esophageal
Solid and liquid dysphagia
Chest pain
Achalasia
Esophageal spasm
Scleroderma
Eval:
esophagram
EGD (to exclude)
esophageal manometry
Cases and pics** in ppt
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