Gastro-oesophageal reflux
How the barrier at the gastro-oesophageal junction fails, why acid and pepsin injure the squamous lining of the oesophagus, and how healing can leave a stricture or a columnar (Barrett’s) lining.
By the end, you can
- Describe the parts of the anti-reflux barrier: the lower oesophageal sphincter, the crural diaphragm and the angle of His.
- Explain how transient sphincter relaxations, low sphincter pressure and a hiatus hernia allow reflux.
- Explain how acid and pepsin injure the oesophageal epithelium and cause heartburn and oesophagitis.
- Relate repeated injury and healing to stricture and to Barrett’s metaplasia.
- Recognise the classic endoscopic and biopsy appearances, gradings and tests of reflux disease and Barrett’s oesophagus, and explain how each main treatment acts on the mechanism.
What it is
Gastro-oesophageal reflux is the passage of stomach contents into the oesophagus. It happens briefly in everyone; gastro-oesophageal reflux disease (GORD) is reflux that causes troublesome symptoms or injury to the oesophagus. It may leave the lining looking normal (non-erosive reflux disease) or inflamed and broken (erosive oesophagitis).
3 types to tell apart
- Physiological reflux
- Short episodes, mostly after meals, cleared within seconds to minutes by peristalsis and saliva. No symptoms and no injury.
- Non-erosive reflux disease
- Troublesome symptoms, often heartburn, with a lining that looks normal at endoscopy. Acid reaches nerve endings through leaky junctions between cells.
- Erosive oesophagitis
- Reflux has broken the surface into erosions or ulcers. It can bleed, scar into a stricture or heal with a columnar (Barrett’s) lining.
US spelling: oesophageal → esophageal, oesophagus → esophagus, oesophagitis → esophagitis.
Normal function
The barrier at the gastro-oesophageal junction
The carries food to the stomach by peristalsis. Its last few centimetres pass through the diaphragm and join the stomach at the . Here a zone of thickened circular muscle, the lower oesophageal sphincter (LES), stays contracted at rest and relaxes only when a swallow arrives.
The sphincter is one part of an anti-reflux barrier. The crura of the diaphragm wrap round the junction and squeeze it, most strongly on breathing in. The short segment of oesophagus inside the abdomen is pressed shut by abdominal pressure, and the oesophagus enters the stomach at an acute angle (the angle of His, at the ), so a full pushes the junction closed like a flap valve.
Brief reflux happens in everyone, especially after meals. It does little harm because the oesophagus clears itself: a wave of peristalsis returns most of the fluid to the stomach, and swallowed saliva, which contains bicarbonate, neutralises the acid left on the lining.
Underlying change · Step 1 of 4
How the barrier fails
The full lesson is part of Student Pro
It takes you through all 4 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Disrupted function · Step 2 of 4
Acid and pepsin injure the lining
The full lesson is part of Student Pro
It takes you through all 4 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Consequences · Step 3 of 4
Bleeding, scarring and effects beyond the oesophagus
The full lesson is part of Student Pro
It takes you through all 4 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Consequences · Step 4 of 4
Barrett’s oesophagus: a change of lining
The full lesson is part of Student Pro
It takes you through all 4 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Symptoms and signs
Symptoms, signs and findings
The full lesson is part of Student Pro
It takes you through all 4 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Exam detail
Exam detail
The full lesson is part of Student Pro
It takes you through all 4 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Treatment
How treatment works
The full lesson is part of Student Pro
It takes you through all 4 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Recap
Recap
The full lesson is part of Student Pro
It takes you through all 4 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Self-check
Check your understanding
The full lesson is part of Student Pro
It takes you through all 4 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .