Once you have mastered
H pylori gastritis and the
atrophic gastritides,
there are only a few more
gastritides about which
we know anything
Lymphocytic
Gastritis
At low power, there is inflammation,
mainly superficial. Check out the
mess in the surface epithelium!
Surface epithelial
lymphocytosis with
epithelial injury
Same surface as in sprue
Plasmacytosis in LP
H pylori associated lymphocytic gastritis
H pylori immunostain in an adjacent field
Lymphocytic
gastritis can
produce polyps
Some cases of lymphocytic gastritis have the giant
folds and protein losing of Menetrier’s disease
Small patches of lymphocytic gastritis
like this pop up next to all kinds of things
Lymphocytic gastritis
next to a carcinoma
Lymphocytic Gastritis
Clinical Aspects
• Endoscopic:
nothing, polyps, giant folds
• Clinical:
nothing, sprue-associated,
Menetrier’s syndrome,
H pylori elsewhere
FOCAL …ITIS
Very, very common
 More common after search
 More common if there are residents
 The entire gut is at risk
 Almost never diagnostic
 Annoying

The more foci the better!
2 tiny foci of gastric inflammation
Multiple
tiny foci
One
big
focus
Often mainly
lymphocytes
with PMNs,
macrophages and
epithelial damage
Was found often in
patients with Crohn’s
Then it was found in
patients with UC
Given the name “focally
enhanced gastritis”
Every so
often a
granuloma
or 2 may be
part of focal
gastritis
Chemical
(Reactive)
Gastropathy
At low power, the dominant change
is the prominence of the PITS
The high N:C
resembles
dysplasia
PITS, PITS
and more
PITS, often
serrated
contours
This change is an expansion
of the proliferative zone
(actually, the neck region, not
the pits) in compensation for
surface epithelial injury.
This is very common in our
practice. Most of the time, we
do not know the cause.
Stomach
Small
bowel
Originally described on the gastric side of a
gastro-enteric anastomosis, due to bile reflux
Superimposed erosion
(necrotic superficial mucosa
In almost 20 year old studies of
patients with chronic NSAIDs use.
Not much change recently.
Gastric erosions occur in 40-60%
Gastric ulcers occur in 10-30%
Duodenal ulcers occur in 5%
Acute erosion—resembles
acute ischemic injury