Disorders of the Gallbladder and Appendix

Learning Objectives

  • Identify normal anatomical location and function of gallbladder and appendix.

  • List common pathologies: gallbladder (cholelithiasis, cholecystitis) and appendix (acute appendicitis).

  • Describe bile storage and release processes; appendix role in immune function.

  • Explain obstruction leading to inflammation in cholecystitis and appendicitis.

  • Connect clinical signs/symptoms (e.g., Murphy’s sign) to pathophysiology.

  • Apply pathophysiology to explain typical lab findings in appendicitis and cholecystitis.

  • Compare acute vs chronic gallbladder disease presentations.

  • Analyze structural changes contributing to clinical manifestations in inflammation.

  • Connect assessment findings (e.g., RUQ pain) to micro/macro structural changes.

Gallbladder Anatomy & Function

  • Pear-shaped organ under the liver; stores/concentrates bile.

  • Releases bile into duodenum via common bile duct.

  • Important for fat digestion; regulated by cholecystokinin (CCK).

  • Not essential for life; dysfunction leads to issues.

Cholelithiasis (Gallstone Formation)

  • Multifactorial causes: bile composition, motility, and mucin dynamics.

  • Types of stones:

    • Cholesterol stones: supersaturation, risk factors include estrogen, obesity.

    • Black pigment stones: composed of calcium bilirubinate; linked to hemolytic anemias.

    • Brown pigment stones: arise from biliary infection (e.g., cholangitis).

  • Symptoms include biliary colic; 80% asymptomatic.

Cholecystitis (Gallbladder Inflammation)

  • Common complication of gallstones; caused by cystic duct obstruction.

  • Leads to bile flow obstruction and potential secondary bacterial infection (e.g., E. coli).

Choledocholithiasis (Stones in Common Bile Duct)

  • Obstruction occurs when gallstones migrate into the common bile duct.

  • Causes bile flow impairment, leading to intrahepatic dilation and cholestasis.

  • Symptoms: obstructive jaundice, RUQ pain, fever.

Acute Ascending Cholangitis

  • Life-threatening biliary tract infection; usually from choledocholithiasis.

  • Characterized by bile stasis and ascending infection from the duodenum.

  • Classic presentation: Charcot's triad (RUQ pain, fever, jaundice).

Appendix: Structure and Function

  • Tubular structure at cecum; involved in mucosal immunity.

  • May serve as a reservoir for gut microbiota.

  • Inflammation can lead to acute appendicitis.

Appendicitis (Appendix Inflammation)

  • Often caused by luminal obstruction (fecalith, hyperplasia).

  • Pathophysiology: obstruction leads to increased pressure and potential necrosis.

  • Symptoms: classic migration of pain to RLQ (McBurney’s point), fever, leukocytosis.

Comparing Appendicitis and Cholecystitis

  • Appendicitis: luminal obstruction, mucosal ischemia, pain in RLQ.

  • Cholecystitis: cystic duct obstruction, bile stasis, pain in RUQ.

  • Common organisms: E. coli predominant in both conditions, with differing additional pathogens.