Exocrine Pancreas, Gallbladder, and Liver Pathology Flashcards
ANNULAR PANCREAS
Developmental malformation in which the pancreas forms a ring around the duodenum
risk of duodenal obstruction
ACUTE PANCREATITIS
- Pathogenesis? $ Which enzyme is most responsible for this disease?*
- Type of damage that occurs?*
- Major causes?*
Inflammation and hemorrhage of the pancreas
- Due to autodigestion of pancreatic parenchyma by pancreatic enzymes: Premature activation of trypsin leads to activation of other pancreatic enzymes.
- liquefactive hemorrhagic necrosis of the pancreas and fat necrosis of the peripancreatic fat
- Most commonly due to alcohol and gallstones; other causes include trauma,hypercalcemia, hyperlipidemia, drugs, scorpion stings, mumps, and rupture of a
posterior duodenal ulcer.
ACUTE PANCREATITIS
Clinical features
- Epigastric abdominal pain that radiates to the back.
- Nausea and vomiting
- Periumbilical and flank hemorrhage (necrosis spreads into the periumbilical soft tissue and retroperitoneum)
- Elevated serum lipase and amylase; lipase is more specific for pancreatic damage.
- Hypocalcemia (calcium is consumed during saponification in fat necrosis)
ACUTE PANCREATITIS
Complications
- Shock -due to peripancreatic hemorrhage and fluid sequestration
- Pancreatic pseudocyst - formed by fibrous tissue surrounding liquefactive necrosis and pancreatic enzymes
- Presents as an abdominal mass with persistently elevated serum amylase
- Rupture is associated with release of enzymes into the abdominal cavity and hemorrhage.
- Presents as an abdominal mass with persistently elevated serum amylase
- Pancreatic abscess - often due toE coli; presents with abdominal pain, high fever, and persistently elevated amylase
- ** DIC** (enzymes get into blood and activate coagulation enzymes) and ARDS - Chew on alveolar-capillary interface.
CHRONIC PANCREATITIS
Clinical features
Fibrosis of pancreatic parenchyma, most often secondary to recurrent acute pancreatitis Most commonly due to alcohol (adults) and cystic fibrosis (children); however, many cases are idiopathic.
- Epigastric abdominal pain that radiates to the back
- Pancreatic insufficiency- results in malabsorption with steatorrhea and fatsoluble vitamin deficiencies. Amylase and lipase are not useful serologic markers of chronic pancreatitis.
- Dystrophic calcification of pancreatic parenchyma on imaging; contrast studies reveal a ‘chain of lakes’ pattern due to dilatation of pancreatic ducts.
- Secondary diabetes mellitus-late complication due to destruction of islets
- Increased risk for pancreatic carcinoma
PANCREATIC CARCINOMA
$ Risk factors
Clinical features
Serum tumor marker
Prognosis
Adenocarcinoma arising from the pancreatic ducts - Most commonly seen in the elderly (average age is 70 years)
- $ Major risk factors are smoking and chronic pancreatitis
- Epigastric abdominal pain and weight loss
- Obstructive jaundice with pale stools and palpable gallbladder; associated with tumors that arise in the head of the pancreas (most common location)
- $ Secondary diabetes mellitus; associated with tumors that arise in the body or tail (Thin elderly female presenting with diabetes)
- Pancreatitis
- Migratory thrombophlebitis (Trousseau sign); presents as swelling, erythema, and tenderness in the extremities (seen in 10% of patients)
- Serum tumor marker is CA 19-9
Very poor prognosis;1-year survival is < 10%.
Whipple procedure
Treatment for Pancreatic Carcinoma: Surgical resection involves en bloc removal of the head and neck of pancreas,proximal duodenum, and gallbladder
Elderly female presents with diabetes mellitus for the first time. What should be on your differential diagnosis?
Pancreatic carcinoma - Tumors that arise in the **body or tail of the pancreas **may be associated with secondary diabetes mellitus.
BILIARY ATRESIA
- Leads to:*
- Presentation*
Failure to form or early destruction of extrahepatic biliary tree
- Leads to biliary obstruction within the first 3 months of life.
- Presents with jaundice and progresses to cirrhosis
CHOLELITHIASIS
Cause
GALLSTONES
Solid, round stones in the gallbladder.
Due to precipitation of cholesterol (cholesterol stones) or bilirubin (bilirubin stones) in bile.
- Arises with (1) supersaturation of cholesterol or bilirubin, (2) decreased phospholipids (e.g., lecithin) or bile acids (normally increase solubility), or (3) stasis - allows deconjugation
- Drugs like cholestyramine - binds bile acids and decreased bile acids cause precipitation of cholesterol.
Most common type of gallstone?
Risk factors?
Cholesterol stones (yellow) are the most common type (90%), especially in the West
- Usually radiolucent (10% are radiopaque due to associated calcium)
- Risk factors include age (40s), estrogen (female gender, obesity, multiple pregnancies and oral contraceptives), clofibrate, Native American ethnicity,
Crohn disease, and cirrhosis.
Bilirubin stones
- Risk factors*
- Clinical presentation of all gallstones*
- Complications*
Pigmented, composed of bilirubincomposed of bilirubin
- Risk factors include extravascular hemolysis from splenic macrophages (increased bilirubin in bile) and biliary tract infection (e.g., E coli, Ascaris lumbricoides, and Clonorchis sinensis)
- usually asymptomatic
- Complications include biliary colic, acute and chronic cholecystitis, ascending cholangitis, gallstone ileus, and gallbladder cancer.
Types of gallstones
- Cholesterol stones (yellow) most common type (90%), radiolucent, caused by decreased bile acids, stasis, or supersaturatio of cholesterol.
- Bilirubin stones (pigmented) made of bilirubin, usually radiopaque, casued by supersaturation of bilirubin, risk factors include: extravascular hemolysis or biliary tract infections.
BILIARY COLIC
- Cause*
- Complication*
Waxing and waning right upper quadrant pain - Due to the gallbladder contracting against a stone lodged in the cystic duct. Common bile duct obstruction may result in acute pancreatitis or obstructive jaundice.
ACUTE CHOLECYSTITIS
- Pathogenesis*
- $ Presentation*
- Risks if untreated*
Acute inflammation of the gallbladder wall
- Impacted stone in the cystic duct results in dilatation with pressure ischemia,bacterial overgrowth (E coli), and inflammation.
- Presents with right upper quadrant pain, often radiating to right scapula, fever with increased WBC count, nausea, vomiting, and increased serum alkaline phosphatase (from duct damage)
- Rupture if untreated
CHRONIC CHOLECYSTITIS
Cause
$ Hallmark
- Clinical presentation*
- Late complication*
- Risks if untreated*
Chronic inflammation of the gallbladder
- Due to chemical irritation from longstanding cholelithiasis +/- bouts of cholecystitis.
- $ Characterized by herniation of gallbladder mucosa into the muscular wall (Rokitansky-Aschoff sinus)
- Presents with vague right upper quadrant pain, especially after eating
- Porcelain gallbladder is a late complication - Shrunken, hard gallbladder due to chronic inflammation, fibrosis, and dystrophic calcification
Increased risk for carcinoma. Treatment is cholecystectomy, especially if porcelain gallbladder is present.
ASCENDING CHOLANGITIS
- Cause*
- Presentation*
- When is there increased incidence of this condition?*
Bacterial infection of the bile ducts
- Usually due to ascending infection with enteric gram-negative bacteria
- Presents as sepsis (high fever and chills), jaundice, and abdominal pain
- Increased incidence with choledocholithiasis (stone in biliary ducts)
GALLSTONE ILEUS
Cause?
Gallstone enters and obstructs the small bowel - Due to cholecystitis with fistula formation between the gallbladder and small bowel
GALLBLADDER CARCINOMA
- Major risk factors*
- Classic presentation*
- prognosis*
_Adenocarcinoma arising from the glandular epithelium that lines the gallbladderwall _
- Gallstones are a major risk factor, especially when complicated by porcelain gallbladder.
- Classically presents as cholecystitis in an elderly woman
- Poor prognosis
A 45 year old man presents with right upper quadrant pain especially after eating. No symptoms in the past. Most likely diagnosis?
Chronic cholecystitis - inflammation of the gallbladder most likely due to chemical irritation from longstanding cholelithiasis
An elderly woman presents with right upper quadrant pain, especially after eating. What should be on your differential diagnosis?
Presentation of cholecystitis in an elderly woman should be highly suscpective of gallbladder carcinoma - adenocarcinoma arising from the glandular epithelium that lines the gallbladder.
Most common cause of RUQ
Cholecystitis
Cholelithiasis
Gallstones
Cholecystitis
Inflammation/infection of the gall bladder
Cholangitis
Inflammation/infection of the biliary tree
Choledocholithiasis
Gallstones in the bile ducts
Reynolds Pentad
Charcot’s triad (Jaundice, Fever, RUQ) + Hypotension and altered mental status. for (osbtructive cholangitis)
Gold standard for diagnosing gallstones
RUQ ultrasound
Hallmark of cholecystitis
Positive Murphy’s sign - inspiratory arrest on deep palpation due to pain
Bilirubin
- How removed from blood?*
- Types?*
Yellow bile pigment that is a product of heme metabolism
- Removed from blood by liver, conjugated with glucuronate (to make it water soluble), and excreted in bile
- Direct - conjugated with glucuronic acid, water soluble
- Indirect - unconjugated, water INSOLUBLE
JAUNDICE
Yellow discoloration of the skin, earliest sign is scleral icterus (yellow discoloration of the sclera)
- Due to elevated total serum bilirubin, usually > 2.5 mg/dL
- 3 Causes:
- Direct hepatocelluar injury
- Obstruction to bile flow
- Hemolysis
Normal bilirubin metabolism
- RBCs are consumed by macrophages of the reticuloendothelial system.
- Protoporphyrin (from heme) is converted to unconjugated bilirubin (UCB).
- Albumin carries UCB to the liver.
- Uridine glucuronyl transferase (UGT) in hepatocytes conjugates bilirubin.
- Conjugated bilirubin (CB) is transferred to bile canaliculi to form bile, which is stored in the gallbladder.
- Bile is released into the small bowel to aid in digestion.
- Intestinal flora convert CB to urobilinogen, which makes the stool brown. Urobilinogen is also partially reabsorbed into the blood and filtered by the kidney, making the urine yellow.
Jaundice caused by Extravascular hemolysis or ineffective erythropoiesis
Etiology
Lab findings
Clinical features
- High levels of UCB overwhelm the conjugating ability of the liver
- Increased UCB
- $ Dark urine due to increased urine urobilinogen (NOT due to UCB because UCB is not water soluble and, thus, is absent from urine)
- Urine biliruben is Absent (acholuria)
- Increased risk for pigmented bilirubin gallstones
Physiologic jaundice of the newborn
- Etiology*
- Lab findings*
- Clinical manifestations*
- Treatement*
Newborn liver has transiently low UGT activity.
- Increased UCB
- UCB is fat soluble and can deposit in the basal ganglia (kernicterus) leading to neurological deficits and death.
- Treatment is phototherapy (makes UCB water soluble). Does not conjugate UCB, only makes it water soluble.
Crigler-Najjar syndrome
Labs
Manifestations
- Absence of UGT
- Increased UCB
- Kernicterus; usually fatal
Gilbert syndrome
Labs
Manifestations
- Mildly low UGT activity; autosomal recessive
- Increased UCB
- Jaundice during stress (e.g., severe infection); otherwise, not clinically significant
Dubin-Johnson syndrome
- Labs*
- Clinical manifestation*
Deficiency of bilirubin canalicular transport protein; autosomal recessive
- Increased CB
- Liver is dark; otherwise, not clinically significant
Biliary tract obstruction (obstructive jaundice)
- Etiology*
- Labs*
- Clinical manifestation*
Associated with gallstones, pancreatic carcinoma, cholangiocarcinoma, parasites, and liver fluke (Clonorchis sinensis)
- Increased CB (anything in bile will leak into blood), Decreased Urine urobiliniogen and increased alkaline phosphatase
- Dark urine (due to bilirubinuria) and **pale stool (can’t put bile into bowel) **
- Pruritus due to increased plasma bile acids
- Hypercholesterolemia with xanthomas
- Steatorrhea with malabsorption of fat-soluble vitamins (can’t put bile into bowel)
Jaundice due to Viral hepatitis
Inflammation disrupts hepatocytes and small bile ductules.
Increased CB (small bile ducturles damaged causing increased bilirubin in urinedark urine) and UCB (destoryed hepatocytes decreases conjugating ability)
Urine urobilinogen is normal or decreased.
$ HEV infection in a pregant woman
HEV infection .in pregnant women is associated with fulminant hepatitis (liver failure with massive liver necrosis).
Where is HEV commonly acquired from?
Contaminated water or undercooked seafood
Describe the dependence of HDV on HBV for infection
HDV is dependent on HBV for infection;
$ Superinfection upon existing HBV is more severe than coinfection (infection with HBV aJld HDV at the same time)