Term
| What are the tasks of the liver? |
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Definition
- The main task of the liver is to maintain metabolic homeostasis, it doe this by:
- PROCESSING dietary amino acids, lipids, carbohydrates, and vitamins.
- SYNTHESIZING serum proteins.
- DETOXIFICATION and excretion of waste products. |
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Term
| Explain the consequences of damage to the liver. |
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Definition
| - Damage to the liver can cause far reaching consequences in other parts of the body due to the body requiring the stable metabolic function of the liver. |
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Term
| List the normal liver anatomy |
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Definition
- Dual blood supply
- Lobule: functional units of the liver
- Portal Triad:
> Branch of the hepatic artery
> branch of the portal vein
> branch of the bile duct
- Blood flow: periphery through the sinusoids towards the central vein.
- Kupffer's cells |
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Term
| What are the major functions of the liver? |
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Definition
- METABOLIC: The liver metabolizes carbohydrates, fats, and proteins.
- EXCRETORY: The liver excretes bile, a mixture of bilirubin, bile salts, lipids, and other minor components.
- STORAGE: The liver storages carbohydrates and lipids.
- SYNTHETIC: The liver synthesizes major plasma proteins including albumin, coagulation proteins, and many transport proteins. |
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Term
| What is hepatic encephalopathy? |
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Definition
- Cephalic = head, pathy = disease
- If certain materials, such as ammonia are not filtered out by the liver, it can cause neurological problems. |
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Term
T or F
Certain viruses prefer to affect the liver. |
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Definition
True
An example of a disease would be hepatotropism. |
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Term
| Liver cells can/cannot regenerate? |
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Definition
- Liver cells CAN REGENERATE.
- New hepatocytes will rise from the remaining healthy tissue.
- CIRRHOSIS: regeneration takes place, but because of FIBROSIS, NODULES form instead of normal tissue. |
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Term
| What is the livers relationship with getting cancer? |
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Definition
| - The liver CAN give rise to primary tumors, but it is much more involved through METASTASIS. |
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Term
T or F
Bile can form gallstones. |
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Definition
True
Can form gallstones, that may cause obstruction or inflammation. |
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Term
Explain Normal Bilirubin Metabolism
(BIG explanation) |
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Definition
1) Old RBC's are broken down by phagocytic cells of the SPLEEN or KUPFFER cells of the LIVER.
2) Hemoglobin --> Heme + Globin
3) Heme loses iron --> Biliverdin (green pigment) --> Bilirubin (yellow pigment)
4) Bilirubin is released to the blood where it binds to ALBUMIN (UNCONJUGATED - NOT WATER SOLUBLE)
5) Becomes taken up by the liver and becomes CONJUGATED (WATER-SOLUBLE)
6) Conjugated bilirubin is excreted in BILE and sent to the INTESTINES to help break down FATS (EMULSIFIER)
7) Unused bilirubin is converted into UROBILINOGEN by the intestinal bacteria.
> 20% is reabsorbed and sent back to the liver
> 80% is excreted in feces
8) ENTEROHEPATIC CIRCULATION: most of the bile salts are reabsorbed and sent back to the liver (in the Ileum via the hepatic portal v.) |
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Term
| What is another name for Jaundice? |
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Definition
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Term
| Jaundice is a ______, NOT a ________. |
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Definition
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Term
| What characterizes Jaundice? |
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Definition
| - Yellow discoloration of the skin and mucosa. |
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Term
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Definition
| - Caused by elevated BILIRUBIN levels in the BLOOD. (HYPERBILIRUBINEMIA) |
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Term
What is the normal amount of bilirubin in the blood?
Amt. with Jaundice? |
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Definition
- Normal Bilirubin levels: < 1.2 mg/dl
- With Jaundice: > 2-3 mg/dl |
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Term
| What are the different classifications of Jaundice? |
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Definition
- Prehepatic
- Hepatic
- Postheptatic |
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Term
| Describe the classification of Jaundice: Prehepatic |
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Definition
- UNCONJUGATED Hyperbilirubinemia
- SECONDARY to HEMOLYSIS |
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Term
| Describe the classification of Jaundice: Hepatic |
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Definition
- MIXED conjugation types
- Viral Hepatitis, Alcohol liver, Cirrhosis, Tumors, Drugs |
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Term
| Describe the classification of Jaundice: Posthepatic |
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Definition
- CONJUGATED Hyperbilirubinemia
- Obstructive (gallstones, tumors) |
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Term
| Explain the Physiologic and Pathology behind Jaundice in newborns |
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Definition
- Physiologic:
> transient, benign, the first week of life
> mild unconjugated hyperbilirubinemia
- Pathologic ( > 15 mg/dl)
> premature infants
> ABO incompatibility
> phototherapy (helps cure)
> exchange transfusion
>> when levels are 18-20 mg/dl
>> can cross neonatal BBB and cause Cerebral palsy |
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Term
| Histologically, damage to the liver is seen as...? |
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Definition
- Necrosis of liver cells
- Fat accumulation |
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Term
| Explain the extent of liver injuries. |
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Definition
- Mild: Liver cells may completely RECOVER
- Severe: Could lead to severe scarring |
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Term
| Multiple episodes of mild liver injury could have an _______ effect. |
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Definition
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Term
| What is considered LIVER FAILURE? |
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Definition
| - When 80-90% of the liver function is gone. |
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Term
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Definition
- DIFFUSE INFLAMMATION throughout the lobules.
- Associated with liver cell SWELLING, and liver cell NECROSIS
- Variable clinical symptoms:
- ill and jaundiced
- ill and not jaundiced
- subclinical hepatitis (having viral hepatitis but being asymptomatic) |
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Term
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Definition
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Term
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Definition
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Term
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Definition
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Term
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Definition
Delta hepatitis
- only found in people who have Hepatitis B
- less common |
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Term
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Definition
- Often found in THIRD WORLD COUNTRIES
- Fecal-oral route: contaminated water |
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Term
| Explain Hepatitis A (HAV) |
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Definition
- It is an RNA virus, with a 2-6 week INCUBATION PERIOD (takes that long before it'll displayed symptoms in the host.)
- Transmission:
> Direct contact (fecal-oral route)
> Fecal contamination of FOOD or WATER
> often occurs in EPIDEMICS
- The virus is SELF-LIMITING (the immune system will kill off on its own)
- Has NO CHRONIC CARRIERS
- VACCINE available |
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Term
| Explain Hepatitis B (HBV) |
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Definition
- DNA VIRUS with a 6 wk - 4 mo. incubation period.
- Transmission:
> Blood
> Body fluids
- Most infected individuals will eliminate the virus, but about 10% become CHRONIC CARRIERS
- Some chronic carriers develop CHRONIC HEPATITIS
- Vaccine available |
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Term
| Explain Hepatitis C (HCV) |
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Definition
- C as in it's Crappy if you get it.
- RNA virus with a 35-65 day INCUBATION PERIOD.
- Transmission:
> blood
> body fluids
- Most individuals who get it CANNOT eliminate it and become chronic carriers.
- Most chronic carriers develop chronic hepatitis & cirrhosis
- NO VACCINE AVAILABLE |
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Term
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Definition
- A disease in which FAT accumulates in the liver cells, IMPAIRING normal liver function.
- Most common Etiologies:
> Excessive alcohol
> volatile solvents
> drugs and chemicals
> some poisons
- Can be REVERSIBLE if the injurious agent is removed. |
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Term
| Explain ALCOHOLIC LIVER DISEASE |
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Definition
- Think of as "3 phases"
- Phase 1: ALCOHOLIC FATTY LIVER
> Mildest form
> REVERSIBLE if you stop drinking
- Phase 2: ALCOHOLIC HEPATITIS
> Liver cell degeneration
> Leukocyte infiltration
> MALLORY BODIES: irregular pink deposits in the cytoplasm
- Phase 3: ALCOHOLIC CIRRHOSIS
- Diffuse SCARRING throughout the liver that disturbs liver FUNCTION and BLOOD FLOW. |
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Term
| Explain the pathophysiology behind ALCOHOLIC CIRRHOSIS |
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Definition
- Ethanol metabolism results in toxic oxygen radical, acetaldehyde, and DNA damage.
- Ethanol causes fat to be stored in the liver --> ALCOHOLIC FOAMY STEATOSIS (fatty liver)
- Ethanol also causes there to be an INFLAMMATORY response where lots of COLLAGEN is produced.
- Acetaldehyde stimulates hepatic FIBROSIS.
- This all results in impaired function of the liver. |
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Term
| Explain what Cirrhosis of the liver is and what characterizes it. |
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Definition
- Cirrhosis of the liver is an end stage CHRONIC liver disease characterized by:
> bridging septa that causes masses of scar tissue
> degenerating and regeneration of island of hepatocytes
> disruption of the ARCHITECTURE of the entire liver |
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Term
| What are the most common causes of Cirrhosis? |
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Definition
- Alcoholic liver disease
- Chronic Hepatitis (usually HBC or HCV) |
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Term
| What are some of the less common causes of Cirrhosis? |
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Definition
- Severe episode of liver necrosis
- Varous chemicals or drugs
- genetic diseases
- chronic bile duct obstruction |
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Term
CIRRHOSIS;
Progressive fibrosis of the liver results in: |
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Definition
- Severe disruption of the portal blood flow
- Impaired diffusion of solutes between hepatocytes and plasma |
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Term
| What are some major functional disturbances in the liver caused by Cirrhosis? |
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Definition
- Impaired liver function (including from excess ESTROGEN) --> (Normally estrogen is inactivated in the liver for men)
- Portal hypertension |
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Term
| Cirrhosis can also lead to the development of what? |
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Definition
Hepatoceullar Carcinoma
(Cirrhosis has a high risk of developing cancer associated with it) |
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Term
| Define Portal Hypertension |
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Definition
| - An increased pressure in the portal system due to an increased PORTAL BLOOD FLOW OR INCREASED *RESISTANCE* to hepatic perfusion. |
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Term
| What kind of PREHEPATIC problems can cause portal hypertension? |
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Definition
- Thrombi and narrowing of portal vein
- Splenomegaly can shunt excessive blood |
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Term
| What kind of INTRAHEPATIC problems can cause portal hypertension? |
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Definition
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Term
| What kind of POSTHEPATIC problems can cause portal hypertension? |
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Definition
| - Severe RIGHT-sided heart failure |
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Term
| Venous return to the IVC is impaired, causing pressure in the portal veins to ____. |
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Definition
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Term
| What are the major clinical consequences of portal hypertension? |
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Definition
- Ascitis
- Shunting of blood into collaterals
> due to high pressure, blood will find a lower pressure system to get around
> can cause hemorrhoids, or esophageal varices
- Hepatic encephalopathy
- Congestive splenomegaly
> may secondarily cause a variety of hematologic abnormalities |
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Term
| What two main factors causes ASCITES in relation to portal hypertension? |
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Definition
1) Increased PORTAL VEIN PRESSURE causes fluid to leak outside of the capillaries.
2) DECREASED production of ALBUMIN
> Albumin is produced in the liver
> Decreased colloid osmotic pressure in blood |
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Term
| Explain Shunting of blood in relation to portal hypertension |
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Definition
- With high portal vein pressure, collaterals will form to bypass the obstructed liver
- Stomach & Spleen --> SPLENOMEGALY
- esophageal veins --> ESOPHAGEAL VARICES --> frequently rupture --> hemorrhage
- Rectal area --> HEMORRHOIDS |
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Term
| Explain Hepatic Encephalopathy |
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Definition
- A spectrum of disturbances in consciousness: from subtle behavioral changes, to marked confusion, stupor, coma, or even death.
- Hepatic Encephalopathy is due to the shunting of blood around the diseased liver, which exposes the brain to metabolites, such as AMMONIA (able to cross the BBB)
- Liver normally metabolizes ammonia and converts it into urea, which can't cross the BBB). |
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Term
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Definition
- Spleen normally weighs 150 grams
- With Splenomegaly it weighs 500-1000 grams
- Tends to sequester and destroy blood cells resulting in anemia, leukopenia, thrombocytopenia. |
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Term
| What can CAUSE splenomegaly? |
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Definition
- CONGESTIVE causes: Cirrhosis, CHF, obstruction in the splenic vein, portal hypertension.
- INFLAMMATION or INFECTION: viral, or bacterial
- INFILTRATIVE ways: amyloidosis, diabetic lipemia
- TUMORS OR CYSTS: leukemia, Hodgkin's, metastasis |
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Term
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Definition
- When 80-90% of hepatic functional capacity is gone.
DECOMPENSATION: may RESULT from systemic infection, electrolyte disturbances, stress (major surgery, heart failure) and GI bleeding.
- THREE MORPHOLIC CATEGORIES OF DECOMPENSATION:
> MASSIVE HEPATIC NECROSIS: DIRECT damage to the hepatocytes from TOXINS
> CHRONIC LIVER DISEASE: Ending in CIRRHOSIS
> HEPATIC DYSFUNCTION: WITHOUT overt NECROSIS |
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Term
| Explain the CLINICAL signs of liver failure. |
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Definition
Although multiple reasons can cause liver failure, no matter what causes it, the clinical signs will be the same.
- JAUNDICE: Liver doesn't process bilirubin
- HYPOALBUMINEMIA: Decreased OSMOTIC pressure --> Edema/Ascites
- HYPERESTROGENEMIA: local vasodilation of the skin; For MEN: testicular atrophy, gynecomastia (man boobs)
- HYPERAMMONEMIA: Hepatic Encephalopathy
- COAGULOPATHY: Innability to clot since liver normally synthesizes clotting factors
- With liver failure, increased chance of other organ systems failing (ex. splenomegaly) |
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Term
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Definition
- Formation of stones in the gall bladder.
- 20% of the population.
- Stones are entirely or predominantly CHOLESTEROL.
- Due to an insufficient amount of bile salts IN RELATION TO the amount of cholesterol. |
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Term
| Explain the INCIDENCE of Cholelithiasis |
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Definition
- More likely to happen in WOMEN than men: Estrogen increases excretion of cholesterol, and decreases the excretion of bile salts.
- More likely in women who have had CHILDREN, than childless women.
- More likely in OBESE women, than normal weight women
- TWICE as high in women who use oral contraceptive than those who use other forms of birth control. |
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Term
| Explain the COMPLICATIONS of gallstones |
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Definition
- Stones and become lodged in the cystic duct and cause:
> BILIARY COLIC: Severe Abdominal pain with smooth m. spasm
> CHOLECYSTITIS: Inflammation of the gall bladder
> OBSTRUCTIVE JAUNDICE: Stone blocks duct, bile backs up into the liver. |
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Term
| Explain Biliary Cirrhosis |
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Definition
| - Inflammation of the bile DUCTS |
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Term
| Explain the different types of Biliary Cirrhosis |
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Definition
- PRIMARY biliary cirrhosis
> Chronic inflammation and destruction of the INTRAHEPATIC bile ducts.
> AUTOANTIBODIES against the bile duct epithelium.
> Jaundice, Itchy Skin, Xanthoma (fat buildup under skin)
SECONDARY (OBSTRUCTIVE) Biliary Cirrhosis
> Due to longstanding blockage of the EXTRAHEPATIC bile ducts (gallstone, carcinoma)
> Causes stasis of the bile and back up pressure in the bile ducts --> Cholestasis
> followed by portal tract scarring and inflammation |
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Term
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Definition
- Def: RETENTION OF THE BILE due to hepatic dysfunction or biliary obstruction.
- obstruction of the biliary tree causes DISTENSION of bile ducts upstream from it.
- BACK-PRESSURE causes edema and inflammation
- ELEVATED serum alkaline phosphatase
- Location of obstruction:
EXTRAHEPATIC: obstruction of the common bile duct from either a gall stone, or a pancreatic tumor
INTRAHEPATIC: Cirrhosis of the liver, or liver tumor |
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Term
| Explain what's going on inside of CHOLESTASIS |
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Definition
- Hepatocytes enlarge
- dilated canalicular spaces
- bile duct proliferation
- edema and pigment retention with inflammation |
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Term
| Explain TUMORS of the liver and gallbladder |
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Definition
- Primary Carcinoma
> RARE in the united states and canada
> COMMON in african and asian countries: WHY?
>> High incidence of chronic Hep B carriers
LIVER is COMMON site of metastatic carcinoma: WHY?
- Dual blood supply, highly VASCULARIZED |
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Term
| NORMAL PANCREAS physiology |
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Definition
- Has both EXOCRINE and ENDOCRINE functions
When you think EXOCRINE think DUCTS
- "Pancreatic Juice" --> ducts
- Alkaline buffers
- Digestive enzymes
When you think ENDOCRINE think into the BLOOD
- Hormones --> blood
> ALPHA: GLUCAGON (releases glucagon when glucose is all gone)
> BETA: INSULIN
> DELTA: SOMATOSTATIN (inhibits gastric activity) |
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Term
| Explain ACUTE PANCREATITIS |
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Definition
- Due to the escape of pancreatic juices from its pancreatic ducts
- Clinical signs:
- Severe abdominal pain
- Vomiting
- High mortality
Risk Factors:
> Gallbladder disease: blockage of pancreatic and common ducts
> Excessive alcohol consumption:
>> 1) stimulates pancreatic solutions
>> 2) causes a spasm of the hepatopancreatic sphincter |
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Term
| Explain CYSTIC FIBROSIS of the PANCREAS |
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Definition
CF: Abnormal chloride transport across cell membranes
- Causes lots of thick mucus secretions that block the pancreatic ducts, bronchi, bronchioles, and bile ducts
- Blocked pancreatic ducts --> build up of juice --> cystically dilated ducts beome surrounded with dense fibrous tissue. |
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Term
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Definition
| - Failure of the CHEMICAL process of digestion |
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Term
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Definition
| - Failure of the intestinal mucosa to ABSORB and TRANSPORT digested nutrients. |
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Term
| What is: Pancreatic Insufficiency |
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Definition
| - Inadequate production of digestion enzymes leading to poor digestion of food, especially fats --> gas formation, diarrhea |
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Term
| What is: Lactase deficiency |
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Definition
Undigested lactose -> gas formation, OSMOTIC diarrhea
= lactose intolerance |
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Term
| What is: Bile Salt Deficiency |
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Definition
| Leads to poor absorption of fats, and fat-soluble vitamins. |
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Term
| What does Vitamin A deficiency cause? |
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Definition
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Term
| What does Vitamin D deficiency cause? |
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Definition
| Decreased calcium absorption leading to bone (D)emineralization. |
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Term
| What does Vitamin K deficiency cause? |
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Definition
| Blood Klotting (clotting) deficiency |
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Term
| What does Vitamin E deficiency cause? |
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Definition
| Testicular Atrophy, and neurologic defects in children |
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Term
| What causes malabsorption syndromes? |
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Definition
| - Advanced liver disease, obstruction of the common bile duct, diseases of the ileum (Krohn's disease) |
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Term
| Explain PANCREATIC ADENOCARCINOMA |
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Definition
- Increased rate in smokers (30%) and there's a hereditary factor (10%)
- One of the highest mortality rates (15% over 5 years)
- Often occurs at the HEAD of the pancreas
- Often block the COMMON BILE DUCT resulting in: OBSTRUCTIVE JAUNDICE |
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Term
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Definition
- Benign tumor of the ISLET CELLS.
- Often cause episodes of severe HYPOGLYCEMIA --> Leads to SEIZURING |
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Term
| Explain what CAUSES HYPERGLYCEMIA, and what RESULTS from it. |
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Definition
~ Causes of Hyperglycemia: ~
- Diabetes Mellitus
> decrease in insulin
- Chronic Pancreatic disease
> damage of the pancreatic islets
- Various diseases that cause overproduction of Adrenal and Pituitary hormones
> ACTH and glucocorticoids raise blood glucose levels
- Various drugs
- A few rare hereditary disorders
- Hyperglycemia results in: KETOACIDOSIS |
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Term
| Explain the CAUSES of HYPOGLYCEMIA as well as what RESULTS from it. |
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Definition
~ Causes of HYPOGLYCEMIA in diabetics ~
- Reduced intake of food
- Increased physical exercise
- Insulin overdose
- Iatrogenic (medically induced)
- Benign tumor of the beta cells (insulinoma)
- Results of Hypoglycemia
- confusion --> loss of consciousness --> convulsions --> coma --> death |
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