Gastric function test

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 organfor digestion. The main works:
üReservoirofingestedfoodstuffs
üGreatchurningability
üHCL&proteases(pepsin)àinitiationofdigestion
üProductsobtaininthestomach(peptides,aa)àstimulatethereleaseofpancreaticjuiceandbile.

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
•Pepsinogenàpepsin
•Renninàin 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 H2receptor 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:
•normalafterfastingà20-50mlonlyàif100-120ml[
hypersecretion,retentionorregurgitation]
•Consistency:
•Normalrestingcontentàfluidandsmallmucousàno
foodàfoodresidueingastriccarcinoma.
•Color:
•Mostlyclear/colorlessàsometimeduetobileyellowish
/greenANDbrownishanddarkredduetorbcs
•Bile:
•Smallamountduetoregurgitationfromduodenumbut
moreseeninintestinalobstruction.

13. •Mucus:
•Only small amount
•Increased in gastritis and gastric carcinoma.
•Free and total acid
•freeHCl
•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
•Fastingàaspiratethegastriccontentà
[residualjuice]
•Nextonehour,collectgastricjuice.Thisiscalledbasalsecretion[rest]
•Pentagastrinisgiven[5mg/kgbodyweight]
•Stimulategastrinsecretion

18. •Collectthegastricjuiceforonehour[15minuteinterval]
•Itrepresentmaximumsecretion
•EachsampleistestedforaciditybytitratingwithN/10NaOHtopH7.4.
•Endpointisdetectedbyindicator[phenolred]orpHmeter.

19. •BASALACIDOUTPUT[BAO]:referstotheacid
output[millimoleperhour]underbasalcondition.
i.e.,basalsecretion
•MAXIMALACIDOUTPUT[MAO]:referstotheacid
output[millimoleperhour]aftergastric
stimulationbyPentagastrin.i.e.,maximum
secretion
•Normal
•BAO:4-10mmol/hr
•MAO:20-50mmol/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 H2receptor of parietal cellàincreases
cAMP levelàincreases 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 anemiaàachylia 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 givenàhypoglycemia.
•Hypoglycemia is a potent stimulus for gastric acid
secretion via vagal stimulation.
•Complete vagotomy àEven insulin givenàNO
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 endoscopicendoscopic
Stool antigen testculture
Urea breathe testhistology
Serology/antibody testRapid urease testing
Polymerase chain
reaction

36. Urea breathe test

38. THANK YOU