Reflux Esophagitis

Slide 1 · Reflux Esophagitis

Mechanisms • Morphology • Clinicopathologic interpretation

Gastroesophageal reflux disease and esophageal injury

Dr Abu Suraih Sakhri

MBBS, MD (Pathology)

www.abusuraihsakhri.com

Slide 2 · Learning outcomes

Explain the lower esophageal sphincter mechanisms underlying reflux.

Identify the gross and microscopic features of reflux esophagitis.

Relate symptoms and investigation choices to mucosal pathology.

Differentiate reflux injury from eosinophilic and infectious esophagitis.

Slide 3 · GERD is not synonymous with erosive esophagitis

GERD is a clinical condition linked to reflux of gastric contents.

Reflux esophagitis denotes mucosal injury in the esophagus.

Symptoms may occur with little or no visible histologic abnormality.

When injury occurs, the distal squamous-lined esophagus is exposed.

Clinical symptoms and structural injury need not track together.

Slide 4 · Three linked—but distinct—observations

Reflux event

Mucosal response

Gastric contents pass proximally.

Often facilitated by transient sphincter relaxation.

Esophageal squamous epithelium contacts gastric acid.

Hyperemia, erosion, or microscopic reactive changes may follow.

Slide 5 · Anatomic orientation: The distal esophagus

Schematic of the distal esophagus and stomach

Esophageal lumen

Gastric contents

Gastroesophageal junction

Retrograde exposure

Simplified anatomy / histology schematic — not an observed specimen

Slide 6 · The squamous lining resists abrasion, not acid

The esophageal epithelium is stratified squamous.

Its mechanical resilience does not ensure resistance to gastric acid.

The dominant disease mechanism is exposure of this lining to gastric refluxate.

Surface injury depends on exposure, not only on a microscopic defect.

Slide 7 · From reflux episode to tissue injury

Gastric refluxate

Esophageal acid exposure

Mucosal stress or injury

Clinical GERD ± esophagitis

This is a causal teaching schematic, not a fixed sequence occurring in every patient.

Original schematic — editable

Slide 8 · GERD is common but geographically variable

Substantial regional differences in GERD prevalence.

The cited prevalence approaches 30% in several Western and Middle Eastern regions.

East Asia and Australia are described as having prevalence at or below 10%.

These are textbook estimates—not a current population survey.

Do not generalize one region’s prevalence to another.

Slide 9 · Main initiating mechanism: Transient LES relaxation

Transient LES relaxation

Reduced antireflux barrier

Reflux into distal esophagus

Acid-sensitive mucosal exposure

Transient lower esophageal sphincter relaxation is considered a major mechanism.

Original schematic — editable

Slide 10 · Vagal control of transient LES relaxation

Transient relaxation of the lower esophageal sphincter involves vagal pathways.

Gastric distention can trigger these relaxation events.

This allows gastric contents to enter the esophagus without requiring a fixed obstruction.

A functional barrier failure can be intermittent.

Slide 11 · Gastric distention: A plausible reflux trigger

Increased gastric distention

Vagal reflex activation

Transient LES relaxation

Retrograde flow becomes possible

Not every distention episode causes symptomatic or erosive disease.

Original schematic — editable

Slide 12 · Gastric reflux crosses the junction

Schematic of the distal esophagus and stomach

Esophageal lumen

Gastric contents

Gastroesophageal junction

Retrograde exposure

Simplified anatomy / histology schematic — not an observed specimen

Slide 13 · Abrupt intra-abdominal pressure increases

Coughing, straining, and bending may abruptly increase abdominal pressure.

These pressure changes can provoke gastroesophageal reflux.

This mechanism differs from vagally mediated transient LES relaxation.

Different initiating mechanisms converge on the same reflux event.

Slide 14 · Reflux during increased abdominal pressure

Schematic of the distal esophagus and stomach

Esophageal lumen

Gastric contents

Gastroesophageal junction

Higher abdominal pressure

Simplified anatomy / histology schematic — not an observed specimen

Slide 15 · Conditions associated with GERD

Physiologic

Structural / motility

Exposures

Pregnancy

Hiatal hernia

Alcohol

Obesity

Delayed gastric emptying

Tobacco

Increased gastric volume

LES incompetence (hernia-related)

CNS depressants

Slide 16 · Obesity is an associated condition

Obesity among conditions associated with GERD.

It is a relevant clinical context when assessing reflux symptoms.

The textbook excerpt does not quantify its individual attributable risk.

An association is not an individual-level diagnostic criterion.

Slide 17 · Pregnancy may coexist with reflux symptoms

Pregnancy appears in the source list of GERD-associated conditions.

Clinical history should recognize this context.

The excerpt does not assign a pregnancy-specific injury pattern on biopsy.

Slide 18 · Potential modifiers of reflux

Patient exposures

Drug-related context

Alcohol use is associated with GERD.

Tobacco use is associated with GERD.

Central nervous system depressants are associated with GERD.

The source does not specify agent-by-agent risk estimates.

Slide 19 · Delayed gastric emptying and gastric volume

Delayed gastric emptying is among the associated conditions.

Increased gastric volume is another listed factor.

These are particularly relevant when considering a distended stomach as a reflux trigger.

Stomach-related factors can affect an esophageal disorder.

Slide 20 · Why risk factors are not diagnostic tests

Associated condition

Raises clinical suspicion

Symptoms require interpretation

GERD remains a clinical assessment

Presence of obesity, pregnancy, or hernia alone does not establish reflux esophagitis.

Original schematic — editable

Slide 21 · Hiatal hernia and sphincter competence

Schematic of the distal esophagus and stomach

Esophageal lumen

Gastric contents

Gastroesophageal junction

Sliding displacement of the junction

Simplified anatomy / histology schematic — not an observed specimen

Slide 22 · Sliding and paraesophageal hiatal hernias

Sliding type

Paraesophageal type

More common type.

Gastroesophageal junction rises into the thorax.

Can impair lower sphincter competence.

Less common; Penetrates phrenoesophageal membrane defect.

May involve stomach or other organs.

Generally requires surgical repair.

Slide 23 · A hiatal hernia is not equivalent to GERD

Fewer than 10% of adults with hiatal hernia are symptomatic.

Incompetence of the antireflux barrier can produce GERD-like symptoms.

The structural finding alone does not explain every symptom.

Interpret anatomy and symptoms together.

Slide 24 · Two complementary routes to reflux

LES relaxes transiently

Reduced junctional barrier

Gastric contents reflux

Distal squamous exposure

Pressure-provoked reflux is an additional route, not a step in this diagram.

Original schematic — editable

Slide 25 · Reflux injury forms a morphologic spectrum

No specific visible change

Hyperemia / erythema

Erosions

Reactive squamous alterations

Erosions and microscopic reactive changes are not mandatory in every clinical GERD case.

Original schematic — editable

Slide 26 · Mild reflux: The mucosa may look normal

The source describes simple hyperemia as a possible sole endoscopic alteration.

Histology is often unremarkable in mild GERD.

A normal or nonspecific biopsy therefore cannot exclude clinical reflux symptoms.

Mild disease can evade morphology-based confirmation.

Slide 27 · Erythema is a nonspecific endoscopic observation

Hyperemia is seen endoscopically as redness.

Redness alone offers limited etiologic specificity.

Clinical context remains important in interpreting an erythematous esophagus.

Slide 28 · Erosions indicate more substantial injury

More significant reflux may produce esophageal erosions.

An erosion reflects loss of superficial mucosal integrity.

Endoscopic demonstration establishes visible mucosal injury, unlike uncomplicated symptomatic reflux.

Compare visible erosion with histologic reaction.

Slide 29 · Microscopic pattern: The reactive triad

Three findings are emphasized in the Robbins description

Basal zone hyperplasia

Papillary elongation

Scattered intraepithelial eosinophils

Slide 30 · Reactive squamous mucosa: Architectural clues

Squamous epithelium

Basal zone

Papillae of lamina propria

Simplified anatomy / histology schematic — not an observed specimen

Slide 31 · Basal zone hyperplasia

The basal compartment of squamous epithelium becomes expanded.

This is a tissue response associated with reflux-related injury.

Interpret basal thickening with other changes rather than as a stand-alone GERD test.

Reactive architecture is a pattern, not a clinical diagnosis.

Slide 32 · Elongation of lamina propria papillae

Lamina propria papillae extend farther into the squamous mucosa.

This architectural alteration commonly accompanies basal zone hyperplasia.

It can be recognized in well-oriented mucosal sections.

Slide 33 · Inflammatory cells in reflux-related mucosa

Squamous epithelium

Basal zone

Papillae of lamina propria

Simplified anatomy / histology schematic — not an observed specimen

Slide 34 · Eosinophils may be intraepithelial

Increased reflux can be associated with eosinophils in squamous epithelium.

The reflux-associated pattern is described as scattered intraepithelial cells.

Marked clusters or sheets shift concern toward eosinophilic esophagitis.

Cell distribution and density matter in the differential.

Slide 35 · Neutrophils: Interpret cautiously

Neutrophilic infiltration is less frequent in typical reflux esophagitis.

Neutrophils more often with infection or chemical damage.

Consider alternative or additional causes if prominent neutrophils are seen.

Inflammatory-cell type refines, but rarely settles, etiology.

Slide 36 · The endoscope and biopsy answer different questions

Endoscopy

Biopsy

Shows redness, erosions, and other structural findings.

May be normal in mild symptomatic disease.

Samples reactive epithelium and inflammatory cells.

May be histologically unremarkable in mild reflux.

Slide 37 · Morphologic findings are suggestive, not universal

Clinical symptoms

Variable endoscopic change

Variable biopsy change

Integrated interpretation

No single depicted finding is represented here as necessary for all GERD.

Original schematic — editable

Slide 38 · Typical clinical manifestations

Heartburn is a characteristic symptom.

Regurgitation of sour-tasting gastric contents is common.

Dysphagia is another described presenting symptom.

Symptoms often occur after meals.

The symptom pattern frames the clinical diagnosis.

Slide 39 · Heartburn arises in the clinical reflux syndrome

Heartburn is central to the GERD symptom complex.

It is commonly linked temporally to meals.

Its presence does not predict the extent of epithelial injury.

Slide 40 · Regurgitation provides a mechanistic clue

Patients may describe sour gastric contents returning to the esophagus or mouth.

This history is compatible with retrograde gastric flow.

Distinguish regurgitation from painful swallowing and mechanical obstruction.

Slide 41 · Dysphagia requires careful interpretation

Dysphagia may occur with GERD.

Persistent or prominent dysphagia raises concern for structural complications or an alternative cause.

Endoscopic evaluation becomes relevant when stricture or other disease is suspected.

Not every dysphagia complaint is explained by acid reflux.

Slide 42 · Chest discomfort can mimic cardiac pain

Typical reflux symptoms can be mistaken for ischemic heart disease.

Chest discomfort should not be attributed automatically to GERD.

Pathology teaching must preserve the cardiovascular differential.

A presumed reflux explanation must not obscure cardiac evaluation.

Slide 43 · Clinical symptoms and mucosal damage can diverge

Heartburn / regurgitation

Variable symptom severity

Variable histologic change

Poor symptom–histology correlation

The source explicitly says that the correlation is weak.

Original schematic — editable

Slide 44 · GERD diagnosis is usually clinical

Endoscopy and biopsy are generally unnecessary for diagnosis.

Symptom evaluation often establishes a working clinical diagnosis.

Investigation becomes appropriate when the presentation is refractory or complications are suspected.

Routine biopsy is not a prerequisite for ordinary GERD.

Slide 45 · Proton pump inhibitors address acidity

Proton pump inhibitors suppress gastric acid production.

Symptomatic relief in up to 90% of patients.

Treatment response concerns symptoms; It does not provide direct histologic grading.

The textbook response estimate is not a guaranteed individual outcome.

Slide 46 · When the source supports endoscopy

Persistent symptoms despite PPI

Or suspected alternative diagnosis

Or suspected reflux complication

Endoscopic evaluation

The diagram summarizes indications named by Robbins; It is not a comprehensive guideline.

Original schematic — editable

Slide 47 · Suspected findings prompting endoscopy

Alternative diagnosis

Complication

Other concern

Eosinophilic esophagitis

Stricture

PPI-refractory symptoms

—

Ulceration

Persistent unexplained symptoms

—

Barrett esophagus

Assessment of mucosal injury

Slide 48 · Chronic reflux and Barrett esophagus

Long-standing GERD

Metaplastic epithelial replacement

Intestinal-type mucosa in esophagus

Increased adenocarcinoma risk

Barrett is a complication of chronic GERD; Progression is not inevitable.

Original schematic — editable

Slide 49 · Barrett esophagus represents metaplasia

Chronic GERD can be complicated by intestinal metaplasia of esophageal squamous mucosa.

The process differs from acute superficial erosion.

Barrett esophagus carries an increased risk of esophageal adenocarcinoma.

Not every patient with GERD develops Barrett esophagus.

Slide 50 · Reflux esophagitis and Barrett esophagus

Reflux esophagitis

Barrett esophagus

Reactive squamous epithelium.

Hyperemia or erosion.

Basal hyperplasia and papillary elongation.

Columnar metaplastic epithelium above the junction.

Goblet cells can establish intestinal metaplasia.

Long-term neoplastic risk is clinically important.

Slide 51 · Barrett esophagus: Endoscopic and biopsy clues

Metaplastic red, velvety mucosa may extend proximally as tongues.

Endoscopic location relative to the gastroesophageal junction is important.

Goblet cells are a key histologic marker of intestinal metaplasia account.

Slide 52 · Reflux may cause structural complications

The Robbins discussion lists strictures and ulcerations among suspected GERD complications.

Dysphagia may motivate evaluation for narrowing.

The clinician should not infer a stricture from symptom severity alone.

Complication suspicion changes the investigation plan.

Slide 53 · Eosinophilic esophagitis versus GERD

Reflux esophagitis

Eosinophilic esophagitis

Acid-exposure clinical context.

Erosions may be visible.

Scattered eosinophils with reactive squamous change.

Frequently associated with atopy.

Food impaction and dysphagia can occur.

Ringed/furrowed esophagus; Prominent superficial eosinophils.

Slide 54 · Eosinophils alone do not establish EoE

GERD can contain intraepithelial eosinophils.

Eosinophilic esophagitis more typically has numerous superficial cells and clusters or sheets.

Clinical and endoscopic context is needed because microscopic findings overlap.

Avoid diagnosing EoE from a nonspecific isolated cell finding.

Slide 55 · Other esophagitis patterns to distinguish

Etiology

Characteristic context

Key clue

Reflux

Postprandial GERD symptoms

Reactive squamous pattern ± erosion

Pill / chemical

Corrosive or lodged medication exposure

Chemical mucosal injury

Candida

Susceptible host

Adherent gray-white pseudomembranes

HSV

Viral esophagitis

Punched-out ulcers; Epithelial inclusions

CMV

Immunosuppression

Ulcers; Stromal/endothelial inclusions

Slide 56 · Case: Reflux symptoms with a normal biopsy

A patient reports recurrent postprandial heartburn and sour regurgitation. Endoscopy reveals no erosion, and the distal esophageal biopsy has no specific abnormalities.

Interpretive questions

Does normal histology exclude GERD?

Is biopsy necessary for all suspected GERD?

Slide 57 · Case: Reactive distal squamous epithelium

A distal esophageal biopsy shows basal zone hyperplasia, elongated lamina propria papillae, and scattered intraepithelial eosinophils.

Interpretive questions

What pattern does the biopsy support?

What clinical information is needed?

Slide 58 · Case: Dysphagia despite acid suppression

A patient has ongoing dysphagia despite treatment with a proton pump inhibitor. The physician suspects a stricture or eosinophilic esophagitis.

Interpretive questions

Why is endoscopy relevant?

Which findings could alter the diagnosis?

Slide 59 · Case: A ringed esophagus

An adult with atopy and recurrent food impaction has an esophagus with ring-like folds and linear furrows. Biopsy shows numerous superficial intraepithelial eosinophils.

Interpretive questions

Which diagnosis is favored over uncomplicated GERD?

Why is merely finding eosinophils insufficient?

Slide 60 · Integrated approach to suspected reflux

Symptom pattern

Assess associated conditions

Investigate refractory / complicated cases

Correlate any endoscopic or histologic injury

Do not expect severity of symptoms and injury to correlate closely.

Original schematic — editable

Slide 61 · Essential morphologic and clinical synthesis

Reflux is commonly driven by transient LES relaxation and can be pressure-provoked.

Early mucosal findings range from no change to hyperemia; Deeper injury may erode.

Basal hyperplasia, papillary elongation, and scattered eosinophils are characteristic but nonspecific.

GERD is often diagnosed clinically; Endoscopy targets refractory symptoms and suspected complications.

Separate the reflux mechanism, the observed tissue response, and the clinical syndrome.

Slide 62 · Key source and further reading

Robbins, Cotran & Kumar

Pathologic Basis of Disease, 11th edition (2026)

The Gastrointestinal Tract — esophageal disorders

Lecture focus: reflux esophagitis, with selected adjacent material on eosinophilic esophagitis and Barrett esophagus.