Gastritis
How NSAIDs, alcohol and critical illness erode the stomach lining within hours, how Helicobacter pylori and autoimmunity inflame it for decades in different regions, how chemical gastropathy differs, and how the Sydney system describes it.
By the end, you can
- Distinguish acute from chronic gastritis by the cells present, and gastritis from gastropathy.
- Explain how NSAIDs, alcohol, bile and poor mucosal blood flow in critical illness breach the mucosal barrier and cause erosions and bleeding.
- Compare Helicobacter pylori gastritis, autoimmune gastritis and reactive gastropathy by site, histology and effect on acid, gastrin and absorption.
- Explain why the site of chronic gastritis predicts high or low acid and which complications follow.
- Describe a gastritis with the updated Sydney system, recognise its tests and classic biopsy appearances, and explain how acid suppression, mucosal protectants, H. pylori eradication and vitamin B12 act on the mechanism.
What it is
Gastritis is inflammation of the stomach lining (gastric mucosa). Acute gastritis is short-lived, with neutrophils, oedema and often erosions and bleeding; chronic gastritis lasts months to decades, with lymphocytes and plasma cells, and is mainly caused by Helicobacter pylori or autoimmunity. Injury and regeneration with little inflammation, as from bile or long-term NSAIDs, is called gastropathy.
5 types to tell apart
- Acute erosive (haemorrhagic) gastritis
- Chemical injury (NSAIDs, alcohol, corrosives) or poor mucosal blood flow in critical illness (stress gastritis); erosions and bleeding within hours to days.
- Chronic Helicobacter pylori gastritis (type B)
- The commonest gastritis worldwide: a chronic active gastritis that starts in the antrum and can spread through the body.
- Autoimmune gastritis (type A)
- Immune destruction of parietal cells in the body and fundus, sparing the antrum; leads to loss of acid and intrinsic factor and to pernicious anaemia.
- Reactive (chemical) gastropathy (type C)
- Repeated injury from bile reflux, long-term NSAIDs or alcohol; regenerating, hyperplastic pits with few inflammatory cells.
- Uncommon forms
- Lymphocytic and eosinophilic gastritis, granulomatous gastritis (Crohn’s disease, sarcoidosis), infections such as cytomegalovirus in people with weak immunity, and radiation injury.
US spelling: oedema → edema.
Normal function
A barrier over a quiet lamina propria
The surface of the stomach is a sheet of mucus-secreting cells over . Its defences, described in peptic ulcer disease, are a mucus–bicarbonate layer, tight junctions, rapid renewal and a rich blood flow, all sustained by prostaglandins. Together they form the gastric mucosal barrier: they keep hydrogen ions in the lumen, and blood flow carries away any acid that enters the tissue.
In the healthy stomach the between the glands holds only scattered lymphocytes and plasma cells, with no neutrophils and no lymphoid follicles. Pathologists read gastritis against this baseline: neutrophils mark acute or active injury, an excess of lymphocytes and plasma cells marks chronic gastritis, and fewer glands above the mark atrophy.
The regions differ. The body and fundus carry oxyntic glands with acid-secreting parietal cells; the antrum carries mucous glands with gastrin-secreting G cells. Because each cause of gastritis prefers one region, biopsies from both are needed to name the type.
Underlying change · Step 1 of 6
Acute erosive gastritis: chemicals breach the barrier
The full lesson is part of Student Pro
It takes you through all 6 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 .
Underlying change · Step 2 of 6
Stress gastritis: ischaemia in critical illness
The full lesson is part of Student Pro
It takes you through all 6 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 .
Underlying change · Step 3 of 6
Helicobacter pylori: an antral gastritis that lasts decades
The full lesson is part of Student Pro
It takes you through all 6 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 .
Underlying change · Step 4 of 6
Autoimmune gastritis: the body’s parietal cells destroyed
The full lesson is part of Student Pro
It takes you through all 6 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 .
Underlying change · Step 5 of 6
Reactive gastropathy: injury with little inflammation
The full lesson is part of Student Pro
It takes you through all 6 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 6 of 6
Where the gastritis sits decides what follows
The full lesson is part of Student Pro
It takes you through all 6 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 6 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 6 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 6 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 6 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 6 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 .