Helicobacter pylori infection and its consequences

1. Helicobacter pylori infection and its consequences

2. We pathologists knew squat about gastritis before H pylori was discovered.

3. H pylori infects the whole stomach, but it induces a chronic gastritis that is most intense in the antal mucosa

4. Classic H pylori gastritis: the great blue biopsy

5. Plasmacytosis (superficial) in the lamina propria

6. Induced lymphoid follicles at the base of the mucosa

7. Activity with PMNs in the necks

8. In most cases, the bacteria can be found in the H and E stained section, on the surface epithelium, often over the intecellular junctions and beneath the surface mucus coat. They appear as tiny thin rods often with a bend in the center, like a set of wings.

9. Bugs on the surface of the epithelium

10. Often they hide in the detached mucus

11. Not all H pylori gastritis is the same. • There may be • population differences • individual differences • minimal disease with tons of bugs • intense disease with few bugs • variable eosinophils • variable activity

12. H pyloriidentification when they are difficult to find on H&E; other stains have been used. Silver Diff-quick

13. Immunostain, our current method H pyloriidentification when they are difficult to find on H&E

14. Active H pylori antral gastritis

15. H pylori killer H pylori Gastritis • Untreated • Plasmacytosis • Activity • Bugs • Lymphoid hyperplasia • Treated • Bugs disappear • Activity stops • Plasmacytosis recedes • Lymphoid follicles atrophy

16. H pylori killer

17. Biopsies that look like treated H pylori gastritis are common

18. Superficial Plasmacytosis

19. No activity. No bugs on the surface.

20. Usually, this inactive chronic gastritis has no H pylori

21. In the pits In the glands These days, a few biopsies of inactive chronic gastritis have bugs on immunostain, often deep in the pits and even in the glands and not on the surface.Thid may result from chronic PPI use

22. Otherwise, this common inactive chronic gastritis without H pylori has no name and no literature.But we keep seeing it.

23. Chronic inactive gastritis,with no bugs: WHY? • Biopsy missed bugs • different cause • proton pump inhibitors • antibiotics

24. Approach to patients with heartburn and dyspepsia First, acid suppression, commonly Proton Pump Inhibitors (PPIs) If no response, then upper endoscopy and potential biopsies

25. antral pH Protein pump inhibitor effects Parietal cell acid secretion • Hypergastrinemia • Parietal cell hypertrophy: snouts • ?Parietal cell hyperplasia • ?Polyps containing fundic glands • ECL cell stimulation in humans unclear

26. antral pH Protein pump inhibitor effects Parietal cell acid secretion • Treats antralH pylori: • Bugs migrate proximally or deeply • activity disappears • Plasmacytosis recedes • lymphoid follicles atrophy

27. H pylori • Causes: • peptic ulcers ( mechanism unknown), a clinical disease • chronic active gastritis, mostly antral, not a clinical disease

28. Complications of H pylori infection Peptic ulcers, mainly in the duodenum Adenocarcinoma, secondary to dysplasias that develop in atrophic gastritis (see atrophic gastritis module for definitions and diagnostic criteria) B cell lymphomas, both low and high grade, probably developing in the induced lymphoid follicles at the base of the mucosa

29. There is a second bacterium that causes an active chronic gastritis, similar to, but less intense than, H pylori gastritis.

30. Helicobacter heilmannii

31. Helicobacter heilmannii is really rare around here. • The bugs: • 7-10 microns • Urease + • Dog and cat transmitted • The disease: • 39 cases in 15,180 antralbxs (Heilmann & Borchard, Gut 32:137, 1991 • Antrum 100%; body 20% • Chronic active -it is, less than H pylori

32. H heilmannii comes from household pets, so don’t share eating utensiles with your cats and dogs unless you eat first.