Diagnostic tests for GI disorders

Diagnostic tests for GI disorders- include physical evaluation, blood tests, imaging techniques. Learn the methods of diagnosis in detail, for gastrointestinal disorders.

1. DIAGNOSTIC TESTS FOR
GASTROINTESTINAL
DISORDERS

2. CONTENTS
⮚PhysicalEvaluation
⮚LabTests
⮚Endoscopicprocedures
⮚ImagingTests

3. PhysicalEvaluation
•Observation:-Fever,Dehydration,Skinrashes.
•ExaminationofNutritionalStatus–SignsofWeightLoss.
•ExaminationofHands–Clubbingoffingers(signofheartorlungdisease),
Koilonychia(spoonnails,asignofanaemia),etc.
•ExaminationofMouth,HeadandNeck–Mouthulcers,Dentition,
Lymphadenopathy,Angularstomatitis,Glossitis,etc.
•AbdominalExamination–Distention,Respiratorymovements,Scars,Lesions,
Colour,Bowelsounds,Ascites,etc.
•ExaminationofGroin–Hernias,Lymphnodes.
•RectalExamination–Fistulae,Haemorrhoids,Masses,etc.

4. LabTests
-Labtestsmayincludeanumberoftestslike–Bloodtests,Breathtests,Faecaloccultblood
test,Stoolculture,etc.dependingonthesuspicionofthephysician.
A.BloodTests
-Inlaboratoryanalysisofblood,specificbloodfactorsarelookedat.
-Thetimefortheresultstocomevaryfromtesttotest.
Examples:
-Celiacdisease–bloodtestresultswillshowhigherthannormallevelsofcertainantibodies
againstaproteincalledgluten,whicharefoundinwheat,barley,andothergrains.
-Inflammatoryboweldisease–bloodtestwillshowanincreasedwhitebloodcellcount,which
mayindicateinflammation.
-Allergies–presenceofIgEantibodies,whicharemadewhenafoodismisidentifiedasathreat
bytheimmunesystem.
-Ulcers(H.pyloriinfection)–bloodtestcanrevealifapersonhasaHelicobacterPyloriinfection,
whichisanindicatorofstomachulcersandcouldputapersonatgreaterriskofstomachcancer
–whichisdeterminedbylookingforanemia—alowamountofwhitebloodcells—whichcan
befoundbyacompletebloodcount(CBC)test.

5. -Incertaincases,antigensmaybedetectedinblooduponinfectionbyavirusor
bacteria.
-ExampleofsuchacaseisHepatitis:
Hepatitis Marker detected in blood test
Hepatitis A Blood test determines IgM antibody to the
hepatitis A virus.
Hepatitis B Blood test determines HBsAg, HBcAb,
HBeAg, IgM anti-HBc, Hepatitis B DNA.
Hepatitis C Blood test determines antibodies to HCV,
Hepatitis C RNA.
Hepatitis D Blood test determines antibodies to HDV.
Hepatitis E Blood test determines antibodies to HEV.

6. B.BreathTests
-Hydrogenbreathtest–Hydrogenbreathtestsarewidely
usedtoexplorepathophysiologyoffunctional
gastrointestinal(GI)disorders.
-Smallintestinalbacterialovergrowth(SIBO)and
carbohydratemalabsorptionaredisordersdetectedby
theseteststhathavebeenproposedtobeofgreat
importanceforsymptomsofGIdiseases.
-Glucosehydrogenbreathtestismoreacceptablefor
diagnosisofSIBO.
-Lactoseandfructosehydrogenbreathtestsareusedfor
detectionoflactoseandfructosemaldigestionrespectively.

7. C.Faecaloccultbloodtest
-Afecaloccultbloodtestchecksforhidden(occult)bloodin
thestool.
-Itinvolvesplacingaverysmallamountofstoolonaspecial
card.
-Thestoolsampleiscollectedandsenttoalabfortesting.
-Bloodinthestoolmaybeasignofcolorectalcancerorother
problems,suchasulcersorpolyps.

8. D.Stoolculture
-Astoolculturechecksforthepresenceofabnormalbacteriainthe
digestivetractthatmaycausediarrheaandotherproblems.
-Thetesthelpsindiagnosingmedicalconditions,suchas
inflammatoryboweldisease,gastricorcoloncancer,analfissures,
H.pyloriinfection,haemorrhoids,aswellastodetectthepresence
ofbloodinyourstoolsample.
-Asmallsampleofstooliscollectedandsenttothelab.
-Resultscomein2-3daysandthetestwillshowwhetherabnormal
bacteriaarepresentornot.
Fig: Stool Culture

9. Endoscopicprocedures
-Endoscopyisaprocedurethatallowsadoctortoviewtheinsideofaperson'sbody.
-Doctorsuseittodiagnosediseasesinthefollowingpartsofthebody:Esophagus,
Stomach,Colon,Ears,Nose,Throat,Heart,Urinarytract,Joints,Abdomen.
-Duringanendoscopy,thedoctorinsertsatoolcalledanendoscopeintoaperson’sbody.
Mostendoscopesarethintubeswithapowerfullightandtinycameraattheend.
-Theendoscope'slengthandflexibilitydependonthepartofthebodythedoctorneedsto
see.
-Forexample,astraightendoscopehelpsadoctorlookatjoints,whereasaflexibleone
helpsadoctorviewtheinsideofthecolon.

10. TypesofEndoscopicprocedures:
1.Colonoscopy
-Usedtoviewthewholelengthofthelargeintestine(colon).
-Itcanhelptofindabnormalgrowths,inflamedtissue,ulcers,and
bleeding.
-Acolonoscopeisputintotherectumandmovedupintothecolon.
-Acolonoscopeisalong,flexibletubewithalightonitthatallowsthe
healthcareprovidertoseetheliningofthecolonandremovetissue
forfurtherstudy(biopsy),ifneeded.
-AvirtualcolonoscopyisavailablethatusesCTimagingtolookatthe
colon.
Fig: Colonoscopy

11. 2.Endoscopic retrograde cholangiopancreatography
(ERCP)
-Allowstodiagnoseandtreatproblemsintheliver,
gallbladder,bileducts,andpancreas.
-ItcombinesX-rayandtheuseofanendoscope.
-Thescopeisguidedthroughyourmouthandthroatand
thenthroughtheesophagus,stomach,andduodenum.
-Thephysiciancanlookattheinsideoftheseorgansand
diagnoseproblems,ifany.
-Atubeisthenpassedthroughthescopeandadye
substanceisinjectedthatallowstheinternalorgansto
appearonanX-ray.
Fig: Endoscopic retrograde cholangiopancreatography

12. 3.Esophagogastroduodenoscopy (EGD or upper
endoscopy)
-AnEGDallowsthephysiciantolookinsidetheesophagus,
stomach,andduodenumwithanendoscope.
-Thisscopeisguidedintothemouthandthroatandthen
intotheesophagus,stomach,andduodenum.
-Heorshecanalsoinsertinstrumentsthroughthescopeto
removeasampleoftissueforbiopsyorforsurgicalremoval
ofatissuemass.
-Whenanultrasoundprobeisattachedtoascope,an
internalultrasoundcanbedone–processknownas
Endoscopicultrasound(EUS).
Fig: Esophagogastroduodenoscopy

13. 4.Sigmoidoscopy
-Asigmoidoscopyisadiagnosticprocedurethatallows
thephysiciantoexaminetheinsideofaportionofthe
largeintestine,andishelpfulinidentifyingthecauses
ofdiarrhea,abdominalpain,constipation,abnormal
growths,andbleeding.
-Ashort,flexible,lightedtube,calledasigmoidoscope,
isinsertedintotheintestinethroughtherectum.
-Thescopeblowsairintotheintestinetoinflateitand
makeviewingtheinsideeasier.
-Asigmoidoscopyisonetypeoftestusedtoscreenfor
colonandrectalcancers.
Fig: Sigmoidoscopy

14. ImagingTests
1.Bariumbeefsteakmeal
-Duringthistest,thepatienteatsamealcontainingbarium(a
metallic,chalkyliquidusedtocoattheinsideoforganssothatthey
willshowuponanX-ray).
-Thisallowstheradiologisttowatchthestomachasitdigeststhe
meal.
-Theamountoftimeittakesforthebariummealtobedigestedand
leavethestomachgivesthephysiciananideaofhowwellthe
stomachisworkingandhelpstofindemptyingproblemsthatmay
notshowupontheliquidbariumX-ray.
-Bariummealexaminationisusuallyperformedtohelpdiseasesof
GITlikeconstrictions,hernias,obstructionsormassesinthe
esophagusorstomach,andinflammatoryorotherdiseasesofthe
intestines.
-Abariumswallowtestmaybedonetodiagnoseproblemsinthe
pharynxandesophagus,canceroftheheadandneck,pharynx,or
esophagus,hiatalhernia,etc.
Fig: Barium beefsteak meal

15. 2.Colorectaltransitstudy
-Thistestshowshowwellfoodmovesthroughthecolon.
-Thepatientswallowscapsulescontainingsmallmarkerswhichare
visibleonX-ray.
-Thepatientfollowsahigh-fiberdietduringthecourseofthetest.
-Themovementofthemarkersthroughthecolonismonitoredwith
abdominalX-raystakenseveraltimes3to7daysafterthecapsuleis
swallowed.
-Thistestismostoftenusedinpatientswhoaresufferingfrom
chronicconstipation.
Fig: Colorectal transit study

16. 3.ComputedTomographyscan(CTscan)
-ItisanimagingtestthatusesX-raysandacomputertomake
detailedimagesofthebody.
-ACTscanshowsdetailsofthebones,muscles,fat,andorgans.
-Acomputerizedtomography(CT)scancombinesaseriesofX-ray
imagestakenfromdifferentanglesaroundyourbodyanduses
computerprocessingtocreatecross-sectionalimages(slices)ofthe
bones,bloodvesselsandsofttissuesinsideyourbody.
-CTscanimagesprovidemore-detailedinformationthanplainX-rays
do.
-ACTscanhasmanyuses,butit'sparticularlywell-suitedtoquickly
examinepeoplewhomayhaveinternalinjuriesfromcaraccidentsor
othertypesoftrauma.
-Itcanbeusedtovisualizenearlyallpartsofthebodyandisusedto
diagnosediseaseorinjuryaswellastoplanmedical,surgicalor
radiationtreatment.
Fig: CT scan

17. 4.Defecography
-DefecographyisanX-rayoftheanorectalareathatevaluates
completenessofstoolelimination,identifiesanorectalabnormalities,
andevaluatesrectalmusclecontractionsandrelaxation.
-Duringtheexam,thepatient'srectumisfilledwithasoftpastethatis
thesameconsistencyasstool.
-ThepatientthensitsonatoiletpositionedinsideanX-raymachine,and
squeezesandrelaxestheanustoexpelthesolution.
-TheradiologiststudiestheX-raystodetermineifanorectalproblems
happenedwhilethepatientwasemptyingthepastefromtherectum.
-Thetechniquetraditionallyinvolvesfluoroscopyandbarium,butan
analogousMRItechniquehasalsobeendevelopedMRIdefecography).
-Thistestisusedtoevaluatedisordersofthelowerbowelthatarenot
diagnosedbytestssuchascolonoscopyorsigmoidoscopy.
Fig: Defecography

18. 5.LowerGIbariumenema
-Itisalsocalledlowergastrointestinalseries.
-AlowerGIseriesisatestthatexaminestherectum,the
largeintestine,andthelowerpartofthesmallintestine.
-BariumintheformofBariumsulfateisgivenintothe
rectumasanenema.
-AnX-rayoftheabdomenshowsstrictures(narrowed
areas),obstructions(blockages),andotherproblems.
-Abariumenemahelpsdoctorsfindhealthconditionsinthe
colonandrectum,suchasinflammation,polyps,and
cancer.
Fig: Lower GI barium enema

19. 6.Magneticresonanceimaging(MRI)
-MRIisadiagnostictestthatusesacombinationoflargemagnets,
radiofrequencies,andacomputertoproducedetailedimagesoforgans
andstructureswithinthebody.
-ThepatientliesonabedthatmovesintothecylindricalMRImachine
whereittakesaseriesofpicturesoftheinsideofthebodyusinga
magneticfieldandradiowavesandthecomputerenhancesthepictures
produced.
-Thetestispainless,anddoesnotinvolveexposuretoradiation.
-BecausetheMRImachineislikeatunnel,somepeopleareclaustrophobic
orunabletoholdstillduringthetesttowhomasedativemaybegivento
helpthemrelax.
-MetalobjectscannotbepresentintheMRIroom,sopeoplewith
pacemakersormetalclipsorrodsinsidethebodycannothavethistest
done.
-Itcanbeusedtodiagnosetumorsoftheabdomenorpelvis.diseasesof
theliver,suchascirrhosis,andabnormalitiesofthebileductsand
pancreas.inflammatoryboweldiseasesuchasCrohn'sdiseaseand
ulcerativecolitis,etc.
Fig: MRI of abdomen
Fig: MRI machine

20. 7.Magnetic resonance
cholangiopancreatography (MRCP)
-ThetechniqueusesMRItovisualizethebiliaryand
pancreaticductsnon-invasively.
-Themachineusesradiowavesandmagnetstoscan
internaltissuesandorgans.
-Thisprocedurecanbeusedtodeterminewhether
gallstonesarelodgedinanyoftheductssurrounding
thegallbladder.
-IndicationsfortheuseofMRCPinclude–unsuccessful
orcontraindicatedERCP,patientpreferencefornon-
invasiveimaging,patientsconsideredtobeatlowrisk
ofhavingpancreaticorbiliarydiseaseandthosewitha
suspectedneoplasticcauseforpancreaticorbiliary
obstruction
Fig: Magnetic resonance cholangiopancreatography

21. 8.Oropharyngealmotility(swallowing)study
-Alsocalledamodifiedbariumswallowtest.
-Thisisastudyinwhichthepatientisgivensmall
amountsofaliquidcontainingbariumtodrinkwitha
bottle,spoon,orcup.
-AseriesofX-raysistakentoevaluatewhathappensas
theliquidisswallowed.
-Itcouldbeusedtodiagnosediseaseslikedysphagia,
sphinctermotilityissues,etc.
Fig: Oropharyngeal motility study

22. 9.Radioisotopegastric-emptyingscan
-Duringthistest,thepatienteatsfoodcontaininga
radioisotope,whichisaslightlyradioactivesubstancethat
willshowuponascan.
-Thedosageofradiationfromtheradioisotopeisverysmall
andnotharmful,butallowstheradiologisttoseethefood
inthestomachandhowquicklyitleavesthestomach,while
thepatientliesunderamachine.
-AGastricEmptyingStudyisatesttodeterminethetimeis
takesamealtomovethroughaperson'sstomach(Gastric
emptyingtime).
-Thetechniqueisusedtodiagnosegastroparesis,acondition
inwhichthestomach'smusclesdon'tworkproperly.
-TypicallyTc-99msulphurcolloidorTc-99mDTPAisthe
radioisotopeused.
Fig: Radioisotope gastric-emptying scan

23. 10.Ultrasound
-Ultrasoundisadiagnosticimagingtechniquethatuseshigh-frequency
soundwavesandacomputertocreateimagesofbloodvessels,tissues,
andorgans.
-Theyareusedtoviewinternalorgansastheyfunction,andtoassess
bloodflowthroughvariousvessels.
-Gelisappliedtotheareaofthebodybeingstudied,suchasthe
abdomen,andawandcalledatransducerisplacedontheskin.
-Thetransducersendssoundwavesintothebodythatbounceoff
organsandreturntotheultrasoundmachine,producinganimageon
themonitor.
-Intestinalultrasoundisasafeandinexpensivemethodthatallows
visualizationofthegastrointestinaltractanddetectionof
abnormalities.
-Thisexaminationinvolvestheuseoftwodifferentultrasound
transducers:alow-frequencyconvexprobeandhigh-frequencylinear
probe.
Fig: Ultrasound

24. 11.UpperGIbariumswallow
-Itisalsocalleduppergastrointestinalseries.
-UpperGIseriesisadiagnostictestthatexaminesthe
organsoftheupperpartofthedigestivesystem:the
esophagus,stomach,andduodenum.
-BariumisswallowedandX-raysarethentakento
evaluatethedigestiveorgans.
-ThetechniqueisusedforthediagnosisofupperGI
tractdiseasesliketumors,ulcers,hernias,diverticula
(pouches),strictures(narrowing),inflammation,and
swallowingdifficulties.
Fig: Upper GI series in infants

25. REFERENCES
1.https://ukhealthcare.uky.edu/digestive-health-
program/diagnosis/blood-tests
2.https://www.hopkinsmedicine.org/health/treatment-
tests-and-therapies/digestive-diagnostic-procedures
3.https://www.urmc.rochester.edu/encyclopedia/conte
nt.aspx?ContentTypeID=85&ContentID=P00364
4.https://teslascans.com/stool-
test/#:~:text=A%20stool%20test%20is%20also,blood
%20in%20your%20stool%20sample.
5.https://www.cancer.net/navigating-cancer-
care/diagnosing-cancer/tests-and-procedures/types-
endoscopy
6.https://www.mayoclinic.org/tests-procedures/ct-
scan/about/pac-20393675
7.https://www.radiologyinfo.org/en/info/mri-abdomen-
pelvis