Investigations of GIT

Investigations of GIT diseases

Tests of structures
Tests of infection
Tests of function
Imaging
Histology
US, CT MRI
Endoscopy
Contrast studies
Plain Radiograph
Bacterial culture
Serology
Breath Tests
Pancreatic Exocrine function
Mucosal Inflammation/ permeability
Absorption
GIT Motility
Radioisotope Tests



It is useful in diagnosis of intestinal obstruction or paralytic ileus The outlines of soft tissues e.g. liver, spleen kidneys may be visible Calcification in the abdominal structures as well as calculi can be detected Abdominal radiographs are not useful in GIT bleeding CXR shows the diaphragm and erect films may detect sub-diaphragmatic free air in cases of perforation

Normal Plain Abdominal Radiograph

Normal Plain Abdominal Radiograph showing the identification of transverse colon

Air under the diaphragm (perforated DU)

Small Intestinal obstruction (multiple fluid levels)

Hiatus hernia (fluid levels behind the heart)

Calcification of the pancreas (chronic pancreatitis)



Toxic megacolon


Indications: Dysphagia Heart burn Chest pain Possible motility disorders Major uses: Strictures Hiatus hernia GERD Motility disorders e.g. achalasia Limitations: Risk of aspiration Poor mucosal detail Unable to biopsy

Esophageal varices as seen by barium swallow

Esophageal carcinoma

Epiphrenic diverticulum as shown by barium swallow

Indications: Dyspepsia Epigastric pain Anemia Vomiting Possible perforation Major uses: GU, DU. Gastric cancer Outlet obstruction Gastric emptying disorders Limitations: Low sensitivity for early cancer Unable to biopsy or assess H pylori

Duodenal bulb

Descending duodenum
Ascending duodenum



Gastric ulcer

Gastric ulcer

Duodenal ulcer


Indications:Diarrhea & abdominal pain of small bowel origin Possible obstruction by strictures etc. Major uses:Malabsorption Crohn’s diseaseLimitations:Time consuming Radiation exposure.

Chronic intestinal psuedoobstruction

Intestinal Tuberculosis At diagnosis
Intestinal Tuberculosis (after 5 months of therapy)

Early stenosing Crohn’s disease

Crohn’s disease


Indications: Altered bowel habit Rectal bleeding Anemia Major uses: Neoplasia Diverticulosis Strictures Megacolon Limitations: Difficult in frail elderly or incontinent patients Sigmoidoscopy is also necessary Possibly misses polyps < 1 cm Less useful in Infl B.D.

Scattered diverticulosis of the left colon

Double contrast barium enema (normal)


Barium enema showing familial adenomatosis coli Arrow point to cancer arise in this setting

Pancolonic diverticulosis

Chronic Ulcerative Colitis

Major uses: Abdominal masses Organomegaly Ascites Biliary tract dilatation Gallstones Guided needle aspiration & biopsy of lesions Limitations: Low sensitivity for small lesions Little functional information Operator dependant Gas & obesity may obscure view

Major uses: Assessment of pancreatic disease Hepatic tumor deposits Tumor staging Assessment of vascularity of lesions. Limitations: Expensive High radiation dose May understage some tumors like esophago-gastric

Major uses:Hepatic tumor staging MRCPPelvic/perianal Crohn’s fistulaeLimitations:Role in GIT disease not fully established Limited availability Time consuming “Claustrophobic” for some. Contraindicated in presence of metallic prosthesis, cardiac pacemaker.


Investigations of GIT diseases
Tests of structures
Tests of infection
Tests of function
Imaging
Histology
US, CT MRI
Endoscopy
Contrast studies
Plain Radiograph
Bacterial culture
Serology
Breath Tests
Pancreatic Exocrine function
Mucosal Inflammation/ permeability
Absorption
GIT Motility
Radioisotope Tests

Video endoscopy unit

Normal esophagus

Esophageal Diverticulum

Malignant esophageal lesion

Esophageal varices

Barrett’s Esophagus

Achalasia

Esophageal Ulcer HIV patient

Normal Stomach Body

Erosive Gastritis

Normal Colonscopy

Stool cultures are essential in the investigation of diarrhea, espicially when it is acute or bloody, to identify pathogenic organism.
Detection of antibodies plays a limited role in the diagnosis of GIT infection caused by organism like H Pylori, Salmonella species, and E. histolytica.