Transcript Slide 1
STOMACH Cell types:
Mucosal surface & foveolae:
Surface foveolar cells - secrete mucous
Mucous neck cells - progenitor cells
Glands:
Mucous cells - secrete mucous & pepsinogen II
Parietal cells - secrete HCl & IF
Chief cells - secrete pepsinogen I & II
Endocrine cells - secrete peptide & amine
hormones
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Congenital Anomalies
CONGENITAL ANOMALIES
Diaphragmatic Hernia:
Defect in diaphragm, away from
esophageal hiatus
Portions of stomach & SI herniate
pulmonary hypoplasia & respiratory
impairment
CONGENITAL ANOMALIES
Heterotopic rests:
Location: Anywhere in the GIT
MC: Pancreatic & gastric
S/S: Usually asymptomatic but may cause
ulceration
CONGENITAL ANOMALIES
Congenital Hypertrophic Pyloric Stenosis:CHiPs
M > F (3:1), 1 in 200 infant males, multifactorial
inheritance
Cause:
Hypertrophy & hyperplasia of circular muscle of pylorus
regurgitation, projectile non- bilious vomiting
commences at 2 - 6 wks of age
May be due to defective autonomic regulation
Dx: Visible peristalsis & palpable mass in RUQ
Tx: Pyloromyotomy is curative
ACUTE GASTRITIS
Other Causes:
Ingestion of strong acids or alkali
Ca chemotx
Radiation
Ischemia & shock
NGTs
- Reduced mucosal blood flow
- Direct damage to mucosal epithelium
ACUTE GASTRITIS
Clinically:
Asymptomatic to epigastric pain of varying
severity, up to acute abdomen w/
hematemesis & shock
major cause of massive hematemesis
(esp. alcoholics)
Common in those who take daily aspirin
for RA
ACUTE GASTRITIS
Morphology:
Mucosal edema & congestion, PMN
infiltration (milder cases)
Erosions (not deeper than muscularis
mucosa) & hges (acute erosive gastritis)
/ dysplasia
CHRONIC GASTRITIS
Pathogenesis:
Autoimmune: Abs to parietal cells
parietal cell destruction ( HCl & IF)
Environmental:
Chronic infection by H. pylori
Alcohol, tobacco, radiation, bile reflux, Crohn’s
disease, uremia, gastric atony
CHRONIC GASTRITIS
Gross:
Red mucosa (thickened or flattened)
Autoimmune fundus & body
H pylori antrum & body
Bile reflux antrum
CHRONIC GASTRITIS
Histology:
Others:
Lympho & plasma cell
infiltrates in LP
(superficial or
involving entire
mucosal thickness)
Regenerative atypia
Intestinal metaplasia
Atrophy
Dysplasia
CHRONIC GASTRITIS
Clinical:
Mild abdominal discomfort, nausea,
vomiting, hypochlorhydria
Autoimmune gastritis:
Hypo- / a- chlorhydria, hypergastrinemia, ~
10% overt PA, long-term risk of Ca is 24%
Helicobacter pylori
~ 50% of
asymptomatic
American adults > 50
yrs are infected
Dx: CLO test
Diseases Association:
Chronic gastritis
PUD
Gastric ca/ lymphoma
PEPTIC ULCERS
Usually solitary ~ 0.6 - 4 cm
MC: duodenum & antrum
Ratio of duodenal: gastric PU is ~ 4 : 1
~ 4 M Americans have PU
Life-time incidence in USA is 10% for men
& 4% for women
PEPTIC ULCERS
Clinical:
Complications:
Epigastric pain 1-3 hrs
PC & worse at night;
nausea; vomiting;
belching, weight loss
Hemorrhage - 25% of
ulcer deaths
Perforation - ~ 2/3 of
ulcer deaths
Obstruction - causes
severe crampy abdominal
pain
Malignant transformation
extremely rare
HYPERTROPHIC GASTROPATHTY
Zollinger-Ellison Syndrome:
Hypertrophic rugal folds
Parietal cell hyperplasia
Peptic ulcers
Markedly elevated serum gastrin levels
Caused by a gastrin secreting tumor
(gastrinoma)
Pancreas is the usual primary site
HYPERTROPHIC GASTROPATHY
Menetrier’s disease:
Affects men in 4th to 6th decades
Epigastric pain, anorexia, vomitting, wt. loss &
peripheral edema
Diffuse rugal hypertrophy
Marked foveolar hyperplasia, smooth muscle
proliferation in LP, glandular atrophy
Hypochlorhydria
Protein-losing enteropathy
GASTRIC POLYPS
Mucosal masses projecting above level of
surrounding mucosa
> 90% non-neoplastic polyps - no malignant
potential
Hyperplastic polyps:
MC type of gastric polyp
Small sessile polyps
May be multiple
No dysplasia no malignant potential
GASTRIC POLYPS (CONT.)
Adenomatous polyps (Adenomas):
May be sessile or pedunculated
Usually solitary
May reach 3-4 cm in dia
Contain proliferating dysplastic epithelium
Are true neoplasms
Up to 40% contain a focus of ca at time of biopsy
Patients with autoimmune gastritis or colonic polyposis
Syndromes have an increased incidence
Gastric polyps need to be biopsied
GASTRIC CARCINOMA
Worldwide distribution variable
US 2.5% of all Ca deaths
5-6 fold decline in incidence over last 70
yrs (for unknown reasons)
GASTRIC CARCINOMA
Classification:
According to Depth of invasion:
Early Gastric Ca:
Confined to mucosa & submucosa
Very good prognosis - ~ 90% 5-year survival, even
w/ limited LN spread
Advanced Gastric Ca:
Extended beyond submucosa
Spread by local invasion, lymphatics, blood (to liver,
lungs & bone)
Virchow node
Bilateral ovarian metastases - Krukenberg
Poor prognosis (<15% 5-year survival)
GASTRIC CARCINOMA
Classification:
According to Gross Pattern:
Exophytic
Flat/depressed
Excavated (ulcerative)
According to Histologic Pattern:
Intestinal type, glandular, expansile
Diffuse type, “signet ring cell”, infiltrating
(linitis plastica)
GASTRIC CARCINOMA
Classification:
Pathologic stage is the most important
prognostic indicator
Less Common Gastric Tumors:
Lymphomas (~ 5%)
Stromal tumors (~ 2%)
Carcinoid tumors (rare)
GASTRIC CARCINOMA
Risk Factors:
Diet: Nitrites (food preservatives), smoked &
salted foods, deficiency of fresh fruits &
vegetables
Host Factors: chronic gastritis (autoimmune & H.
pylori), adenomatous polyps, partial
gastrectomy
Genetic Factors: only ~ 4% of patient’s w/ gastric
CA have a family Hx