Chapter 30 Disorders of Hepatobiliary and Exocrine Pancreas Function

1. Essentials of Pathophysiology Chapter 30Disorders of Hepatobiliary and Exocrine Pancreas Function

2. The liver does not play a role in glucose homeostasis. • Jaundice results from an abnormally high accumulation of bile in the blood. • Hepatitis, inflammation of the liver, is of bacterial origin. • Cholelithiasis, or gallstones, is caused by precipitation of substances contained in bile, mainly cholesterol and bilirubin. • Chronic pancreatitis is a severe, life-threatening disorder associated with the escape of activated pancreatic enzymes into the pancreas and surrounding tissues. Pre lecture quiz true/false F F F T F

3. The __________ cells are capable of removing and phagocytizing old and defective blood cells, bacteria, and other foreign material from the portal blood as it flows through the sinusoid. • One of the metabolic functions of the liver is the conversion of ammonia, which is produced by deamination of amino acids, into __________.  • Pruritus is the most common presenting symptom in persons with cholestasis, probably related to increased bile __________ in the blood. • Hepatitis __________ is the most common cause of chronic hepatitis, cirrhosis, and hepatocellular cancer in the world. • __________ represents the end stage of chronic liver disease in which much of the functional liver tissue has been replaced by fibrous tissue. Pre lecture quiz • C • Cirrhosis • Kupffer • salts • urea

4. System

5. System Interaction

6. Blood from hepatic portal vein and hepatic artery mix in sinusoids The sinusoids empty into central veins, which send the blood to the hepatic vein and inferior vena cava Liver Structure

7. Hepatic cells lie along the sinusoids and pick up chemicals from the blood They modify the blood’s composition Liver Structure(cont.)

8. At the back end of each hepatic cell, bile is released into a canaliculus The bile is carried to the bile duct and then to the gallbladder Liver Structur e(cont.)

9. Many sinusoids come together to empty into one vein The section of the liver emptying into one vein is a lobule Liver Structure (cont.)

10. Tell whether the following statement is true or false. The gallbladder stores bile that has been produced by the liver. Question

11. True Rationale:The liver makes bile and secretes it into the small intestine via the common bile duct. Excess bile is stored in the gallbladder, where it also enters the small intestine through the common bile duct when it is needed. Answer

12. Carbohydrate, protein, and lipid metabolism • Sugars  stored as glycogen, converted to glucose, used to make fats • Proteins  synthesized from amino acids; ammonia made into urea • Fats  oxidized for energy, synthesized, packaged into lipoproteins Metabolic Functions of the Liver

13. Drug and hormone metabolism • Biotransformation into water-soluble forms • Detoxification or inactivation • Bile production Metabolic Functions of the Liver (cont.)

14. Which of the following substances does bile make more susceptible to digestive enzymes? • Carbohydrate • Protein • Fat • All of the above Question

15. Fat Rationale:Bile (produced in the liver) emulsifies fat molecules so that they are easier to digest. An emulsion is a mixture of two immiscible (unblendable) substances, in this case bile and fat. Answer

16. Mr. M had a donut for breakfast. Question: • Explain how the sugar in the donut left his small intestine and ended up as fat in his carotid artery, giving the: • Anatomical structures • Chemical processes • Hormones that controlled them Scenario

17. Ms. B was prescribed an oral medication for her skin problem. She took it twice a day. • The day after she started the medication, Ms. B drank wine with a friend right after taking the prescribed dosage Question: • Ms. B got terribly ill. Why? She said, “I drink that kind of wine all the time.” Scenario

18. Hematologic disorders as the liver fails the spleen takes over some of the function of the liver • Anemia- due to splenomegaly • Thrombocytopenia- due to splenomegaly • coagulation defects- • leukopenia due to splenomegaly • As your spleen grows larger, it begins to filter normal red blood cells as well as abnormal ones, reducing the number of healthy cells in your bloodstream. It also traps too many platelets. Eventually, excess blood cells and platelets can clog your spleen, interfering with its normal functioning. Liver Failure

19. Endocrine disorders • Fluid retention, hypokalemia, Lack of metabolism of aldosterone, too much remains in the system • disordered sexual functions • Which hormones would cause these endocrine disorders? Failure of Cholesterol/Steroid formation Liver Failure

20. Skin disorders • Jaundice, red palms, spider nevi • Hepatorenal syndrome- • Deteriorating liver function is believed to cause changes in the circulation altering blood flow in the kidneys. The renal failure of HRS is a consequence of these changes in blood flow • Azotemia, increased plasma creatinine, oliguria- decreased production of urine • Hepatic encephalopathy- caused by accumulation in the bloodstream of toxic substances that are normally removed by the liver • Asterixis, confusion, coma, convulsions • Asterixis : An uncontrollable flapping of the hands that becomes noticeable when patients stretch out their arms, palms out, as if stopping traffic. Liver Failure (cont.)

21. Jaundice in a Person with Hepatitis A

22. What causes jaundice? • Increased bilirubin levels • Anemia • Thrombocytopenia • Leukopenia Question

23. Increased bilirubin levels Rationale:Erythrocytes are normally broken down in the spleen at the end of their life span. The end product of RBC metabolism is bilirubin. Bilirubin is sent to the liver to be metabolized; if the liver is not functioning properly, the bilirubin accumulates and causes jaundice (an abnormal yellowing of the skin and mucous membranes). Answer

24. Viral hepatitis Hepatitis A virus (HAV) Hepatitis B virus (HBV) Hepatitis B–associated delta virus (HDV) Hepatitis C virus (HCV) Hepatitis E virus (HEV) Hepatitis

25. Which hepatitis viruses are most likely to be the problem in: • An asymptomatic drug abuser? • A nursing student who has spent the last two months volunteering in an orphanage in Mali? • An infant whose mother has hepatitis? Discussion C E B

26. Caused by HBV, HCV, and HDV Principal worldwide cause of chronic liver disease, cirrhosis, and hepatocellular cancer Chief reason for liver transplantation in adults Chronic Viral Hepatitis

27. Fatty liver (steatosis) • Liver cells contain fat deposits; liver is enlarged • Alcoholic hepatitis • Liver inflammation and liver cell failure • Cirrhosis • Scar tissue partially blocks sinusoids and bile canaliculi Alcoholic Liver Disease

28. Alcoholic Liver

29. Alcoholic Liver

30. Liver Cancer

31. Which of the following is the least virulent strain of hepatitis? • HAV • HBV • HCV • HDV Question

32. HAV Rationale:HBV, HCV, and HDV are all virulent strains that may lead to chronic viral hepatitis. HAV is most commonly transmitted by the fecal-oral route (e.g., contaminated food or poor hygiene) and does not typically have a chronic stage (it does not cause permanent liver damage). Answer

33. Portal hypertension causes pressure in these veins to increase Varicosities and shunts develop Organs engorge with blood Veins Draining into the Hepatic Portal System

34. Portal Hypertension

35. Portal Hypertension

36. Effects of Portal Hypertension Hemorrhoids Ascites & Caput medusae

37. Bile flow in the liver slows down • Bile accumulates and forms plugs in the ducts • Ducts rupture and damage liver cells • Alkaline phosphatase released into blood • Liver is unable to continue processing bilirubin • Increased bile acids in blood and skin • Pruritus (itching) Cholestasis and IntrahepaticBiliary Disorders

38. Hemoglobin from old red blood cells becomes bilirubin The liver converts bilirubin into bile Why would a man with liver failure develop jaundice? The Fate of Bilirubin unconjugated bilirubin in blood liver links it bilirubinemia to gluconuride jaundice conjugated bilirubin bile

39. Biliary Tract Gallbladder Hepatic duct Cystic duct Common bile duct Ampulla of Vater Sphincter of Oddi Pancreatic duct

40. Cholelithiasis (gallstones) • Cholesterol, calcium salts, or mixed • Acute and chronic cholecystitis • Inflammation caused by irritation due to concentrated bile • Choledocholithiasis • Stones in the common bile duct • Cholangitis • Inflammation of the common bile duct Disorders of the Gallbladder

41. Emulsifies fats so they can be digested • Passes on to the large intestine • Bacteria convert it to urobilinogen • Some is lost in feces • Most is reabsorbed into the blood • Returned to the liver to be reused • Filtered out by the kidneys  urine Bile in the Intestines

42. The Pancreas Pancreas Exocrine Endocrine pancreas pancreas releases digestive releases hormones juices through a into the blood duct to the duodenum

43. Acini produce: • Inactive digestive enzymes • Trypsininactivator • Bicarbonate (antacid) • These are sent to the duodenum when it releases secretin and cholecystokinin • In the duodenum, the digestive enzymes are activated Exocrine Pancreas

44. Tell whether the following statement is true or false. The exocrine pancreas produces insulin. Question

45. False Rationale:Beta cells of the endocrine pancreas produce insulin; the exocrine pancreas produces digestive enzymes that are secreted into the small intestine through the common bile duct. Answer

46. Biliary Reflux 5. Bile in pancreas disrupts tissues; digestive enzymes activated 1. Gallbladder contracts 2. Bile is sent down common bile duct 3. Blockage forms in ampulla of Vater: bile cannot enter duodenum 4. Bile goes up pancreatic duct

47. Activated enzymes begin to digest the pancreas cells • Severe pain results • Inflammation produces large volumes of serous exudate hypovolemia • Enzymes (amylase, lipase) appear in the blood • Areas of dead cells undergo fat necrosis • Calcium from the blood deposits in them • Hypocalcemia Autodigestion of the Pancreas

48. Have signs and symptoms similar to acute pancreatitis • Often have: • Digestive problems because of inability to deliver enzymes to the duodenum • Glucose control problems because of damage to islets of Langerhans • Signs of biliary obstruction because of underlying bile tract disorders or duct compression by tumors Chronic Pancreatitis and Pancreatic Cancer