Gastric function test slide includes various laboratory test done to rule in and out various gastric disease

1. Gastric function
test

2. Introduction
qStomach is a major organ for digestion. The
main works:
üReservoir of ingested food stuffs
üGreat churning ability
üHCL & proteases (pepsin)à initiation of
digestion
üProducts obtain in the stomach ( peptides, aa
)à stimulate the release of pancreatic juice and
bile.

3. Normal healthy stomach
qIn 24 hours: gastric juice secretion
•Fasting: 1000 ml
•Normal diet : 2000 to 3000 ml.

4. qThe chief constituents of gastric juice
are:
• HCL
• Pepsinogenà pepsin
• Renninà in infant
• Intrinsic factor
• Mucous

6. Gastrin secreted by G cell
↓
Stimulate secretion of HCL
↓
Neg. feed back by acidic pH
↓
Most potent stimulus is histamine
↓
Acts on H2 receptor on gastric mucosa
Normal HCL secretion

8. Indications
• Gastric ulcer
• ZE- syndrome
• Pernicious anemia
• Peptic ulcer
• Gastritis
• Completeness of vagotomy etc.

9. Chemical examination
of
gastric contents

10. qSeveral test for gastric function
evaluation
1. Fractional meal test
2. Alcohol test meal.
3. Penta gastrin stimulation test
4. Augmented histamine test meal
5. Insulin stimulation test [Hollander
test meal].

11. Resting gastric juice [ after fasting]
• Volume:
• Consistency
• Color
• Bile
• Blood
• Mucous
• Free and total acid
• Organic acid.

12. • Volume:
• normal after fastingà 20-50 ml onlyà if 100-120 ml[
hypersecretion, retention or regurgitation]
• Consistency:
• Normal resting contentà fluid and small mucousà no
food à food residue in gastric carcinoma.
• Color:
• Mostly clear/colorlessà sometime due to bile yellowish
/green AND brownish and dark red due to rbcs
• Bile:
• Small amount due to regurgitation from duodenum but
more seen in intestinal obstruction.

13. • Mucus:
• Only small amount
• Increased in gastritis and gastric carcinoma.
• Free and total acid
• free HCl
• Total: protein hydrochloride and any organic acids
• Free acid: 0 to 30 mEq/L
• Total acid:10 mEq/L higher(10 to 40mEq/L)

14. Fractional meal test[ old test]
Aspirate overnight fasting stomach contents
↓
Test meal is given ( rice gruel, black coffee)
↓
Stimulates gastric secretion
↓
Again aspirate content [ for 2 hr., 15 min interval]
↓
Samples analyzed for acidity
[Free acid ranges 15 to 45 mEq/ liter at the maximum]

15. STIMULATION TEST

16. Alcohol stimulation Test
Same as the Previous process
↓
But test meal is 7% alcohol [ 100ml]
↓
Response is more rapid
↓
Test time is reduced to 1 and half hour
↓
Analyze for the acidity, peptic activity, blood, bile,
mucous.

17. Penta gastrin stimulation test
• Fasting à aspirate the gastric content à
[ residual juice]
• Next one hour, collect gastric juice.This is
called basal secretion [rest]
• Pentagastrin is given [ 5mg/kg body
weight]
• Stimulate gastrin secretion

18. • Collect the gastric juice for one hour[ 15
minute interval]
• It represent maximum secretion
• Each sample is tested for acidity by titrating
with N/10 NaOH to pH 7.4.
• End point is detected by indicator [ phenol
red ] or pH meter.

19. • BASAL ACID OUTPUT [BAO]: refers to the acid
output [ millimole per hour] under basal condition.
i.e., basal secretion
• MAXIMAL ACID OUTPUT [MAO]: refers to the acid
output [millimole per hour] after gastric
stimulation by Penta gastrin. i.e., maximum
secretion
• Normal
• BAO: 4-10 mmol/hr
• MAO: 20-50 mmol/hr

20. AUGMENTED HISTAMINE TEST
• All the process is same as Penta gastrin stimulation
test EXCEPT.
• Histamine [ 0.04 mg/kg body weight] is given
subcutaneously
• Acts on the H2 receptor of parietal cellà increases
cAMP levelà increases HCL secretion

21. Interpretation
qIncreased acid output
•Zollinger Ellison syndrome
•Chronic duodenal ulcer
•Gastric cell hyperplasia
•Excessive histamine production [
systemic mastocytosis and basophilic
leukemia]

22. INCREASED ACID
OUTPUT

27. DECREASED ACID
OUTPUT

28. qDecreased acid output
•Gastritis
•Gastric carcinoma
•Partial gastrectomy
•Pernicious anemiaà achylia gastrica [
both enz. and HCL]
•Chronic iron def anemia.

33. Insulin stimulation test
• Also called as Hollanders test
• Done to access the completeness of vagotomy in
duodenal ulcer patient.
• Insulin 0.1 U/Kg body weight is givenà hypoglycemia.
• Hypoglycemia is a potent stimulus for gastric acid
secretion via vagal stimulation.
• Complete vagotomy à Even insulin givenà NO
increase in acid out put compared to basal level.

35. • Other relevant test:
• Serum gastrin level [ < 10 pmol/L] and ZE: > 100
pmol/L
• H . Pylori test [ microbiology]
Non endoscopic endoscopic
Stool antigen test culture
Urea breathe test histology
Serology/antibody test Rapid urease testing
Polymerase chain
reaction

36. Urea breathe test

38. THANK YOU