Gastrointestinal Tract Diseases: Diagnostic Tests
16 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary role of biochemical tests in the investigation of GI tract disease?

  • Uncertain role
  • Minor role (correct)
  • Major role
  • No role
  • Gastrinoma is caused by a neoplasia of pancreatic gastrin-producing cells.

    True

    What is the primary cause of chronic pancreatitis?

    Advanced stages of pancreatic disease

    Elastase is a ______ enzyme that is not degraded in the intestine.

    <p>pancreas-specific</p> Signup and view all the answers

    Match the following investigative techniques with their corresponding uses:

    <p>Urea breath test = Diagnosis of Helicobacter pylori infection Serological tests = Diagnosis of Helicobacter pylori infection Faecal antigen testing = Diagnosis of Helicobacter pylori infection Endoscopy and biopsy procedures = Investigation of GI tract disease in general</p> Signup and view all the answers

    What is the main cause of acute pancreatitis?

    <p>Both a and b</p> Signup and view all the answers

    What is the significance of a 2-fold increase in plasma gastrin levels after secretin injection?

    <p>It is indicative of gastrinoma</p> Signup and view all the answers

    Elevated fasting plasma gastrin levels are indicative of Zollinger-Ellison syndrome.

    <p>True</p> Signup and view all the answers

    Calprotectin is a protein derived from activated neutrophils as a result of inflammation.

    <p>True</p> Signup and view all the answers

    What is a consequence of bacterial colonization in the small intestine?

    <p>Vitamin B12 deficiency</p> Signup and view all the answers

    Match the following investigations with their respective conditions:

    <p>Culture of small bowel aspirate = Celiac disease Small intestine biopsy = Bacterial colonization in the small intestine Faecal occult blood testing = Bowel cancer screening</p> Signup and view all the answers

    The glucose hydrogen breath test measures the production of _______________ in the intestine.

    <p>hydrogen</p> Signup and view all the answers

    What is the name of the autoimmune disorder triggered by a sensitivity to gliadin (gluten protein)?

    <p>Celiac disease</p> Signup and view all the answers

    What is the result of testing for faecal occult blood (FOB) in asymptomatic populations?

    <p>16% reduction in the relative risk of colorectal cancer mortality</p> Signup and view all the answers

    What is the name of the protein that resists degradation in the gut and can be detected in faeces, which is used as a marker of inflammation?

    <p>Calprotectin</p> Signup and view all the answers

    Low immunity leads to aerobic bacterial colonization.

    <p>False</p> Signup and view all the answers

    Study Notes

    Gastrointestinal Tract Disease

    Stomach – Peptic Ulcer

    • Helicobacter pylori (H.pylori) causes peptic ulcer disease and can be diagnosed using:
    • Urea breath test
    • Serological tests
    • Faecal antigen testing
    • Urea breath test:
    • H.pylori produces urease enzyme, which converts urea into ammonia and carbon dioxide
    • Expired isotopically labelled CO2 is collected and quantified

    Stomach – Zollinger-Ellison Syndrome

    • Caused by gastrinoma: a neoplasia of either gastric gastrin-producing cells or pancreatic gastrin-producing cells (more common)
    • ↑ Gastrin secretion leads to:
    • Chronic hypersecretion of gastric acid → peptic ulceration
    • Acidity (↑ [H+]) → ↓ pancreatic lipase → fat malabsorption → steatorrhoea
    • Diagnosis of gastrinoma: based on elevated fasting plasma [gastrin] in the presence of gastric acid hypersecretion
    • Procedure:
    • Stop proton pump inhibitors (PPIs) and H2-receptor blockers
    • Give IV injection of secretin:
      • If 2-fold increase in plasma [gastrin] → gastrinoma
      • If no change → G-cell hyperplasia

    Pancreas – Acute Pancreatitis

    • Mainly due to:
    • Gallstones
    • Alcoholism
    • Infection
    • Amylase arises mainly from:
    • The pancreas (P-isoamylase)
    • The salivary glands (S-isoamylase)
    • Serum P-isoamylase activity is more specific to acute pancreatitis
    • Serum total amylase > 10 times normal value → acute pancreatitis

    Pancreas – Chronic Pancreatitis

    • Chronic pancreatitis (advanced stages) → impaired secretion of pancreatic enzymes → malabsorption and steatorrhoea
    • Diagnosed by pancreatic imaging techniques
    • Elastase:
    • A pancreas-specific enzyme that is not degraded in the intestine
    • High concentration in faeces
    • Low faecal elastase → severe pancreatic insufficiency

    Small Intestine – Bacterial Colonisation

    • Mainly due to:
    • Intestinal stasis (e.g. blind loop, stricture)
    • A colonic fistula
    • Low immunity → anaerobic bacterial colonisation
    • Consequences:
    • Bile salt deficiency
    • Decreased micelle formation
    • Vitamin B12 deficiency
    • Investigation:
    • Culture of small bowel aspirate
    • Glucose hydrogen breath test:
      • Bacteria ferment carbohydrates, producing hydrogen
      • Hydrogen is not produced by mammalian cells
      • Test is not sensitive, but helpful

    Small Intestine and Colon – Celiac Disease

    • Celiac disease: an autoimmune disorder, triggered by a sensitivity to gliadin (gluten protein)
    • First-degree relatives of an affected patient have ↑ risk
    • Also, other autoimmune diseases like DM type-1 and autoimmune thyroiditis
    • Diagnosis:
    • Small intestine biopsy
    • Serological tests: circulating antibodies to tissue transglutaminase (tTG) → test for anti-tTG IgA

    Small Intestine and Colon – GI Inflammation

    • Calprotectin:
    • A calcium-binding protein, derived from activated neutrophils as a result of inflammation
    • Resists degradation in the gut, and can be detected in faeces
    • Highest levels: in inflammatory bowel disease and bacterial infection
    • Increased levels: colon and stomach cancer, colonic polyps and diverticular disease
    • Presence: irritable bowel syndrome (IBS)

    Small Intestine and Colon – Faecal Occult Blood

    • Testing for faecal occult blood (FOB) is a tool for screening asymptomatic populations of bowel cancer
    • This screening results in a 16% reduction in the relative risk of colorectal cancer mortality

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    This quiz covers the diagnostic tests used to investigate gastrointestinal tract diseases, including biochemical tests, microbiological investigations, and more. Learn about the different tests used to diagnose stomach diseases, including peptic ulcer and Helicobacter pylori.

    More Like This

    Use Quizgecko on...
    Browser
    Browser