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Question 1

What are the main components of bile?

Answer 1

-bile acids-phopholipids-cholesterol-immunoglobulin A and M-Mucus-Glutathione

Question 2

What are the main roles of bile acids and phospholipids?

Answer 2

-solubilization of cholesterol

Question 3

Describe bile

Answer 3

The volume of hepatic bile secretion is estimated to be between 500 and 600 ml per day.It is a complex lipid–rich micellar solution that is isoosmotic with plasma and composed primarily of water, inorganic electrolytes, and organic solutes such as bile acids, phospholipids (mostly phosphatidylcholine), cholesterol, and bile pigments.Bile acids are travel down the biliary tree and are stored in the gallbladder. Following a meal, the gallbladder contracts and empties its content into the duodenum

Question 4

What are the main types of gallstones?

Answer 4

-pureand mixed cholesterol stones-pigmented black and brown stones

Question 5

Describe cholesterol stones

Answer 5

these are the most frequent type of stone, yellowish-white in color - Monohydrate cholesterol crystals - Matrix of mucin glycoprotein - Calcium salts of unconjugated bilirubin - Only occasionally seen by x-ray

Question 6

Describe pigmented brown stones

Answer 6

• Calcium salts and deconjugated bilirubin , cytoeskeleton of bacteria - Frequent in patient with previous surgery, infection, and patients with duodenal diverticula

Question 7

Describe pigmented black stones

Answer 7

seen more in patients with liver disease, hemolysis, older age,total parenteral nutrition andare small and very hard - Pure calcium bilirubinate, calcium copper, mucin glycoprotein

Question 8

What things are likely to cause a supersaturated cholesterol bile?

Answer 8

-estrogens and progesterone (aka women) by Increased cholesterol uptake (Increased lipoprotein receptors B and E) (estrogen) and preventing conversion of ACAT to cholesterol ester for storage(Progesterone)-(Inhibitor of AcoA CAT Decreased conversion of cholesterol to cholesteryl ester stores)-Age by preventing/decreasing the production of bile acids (Age related decreased in 7 alfahydroxylase)-Obesity by promoting formation of free cholesterol from acetate via HMG CoA reductase-marked weight reduction/starvation

Question 9

What are the three main parts of thePathophysiology of Cholesterol Stone Formation?

Answer 9

•Cholesterol Supersaturation•Accelerated Nucleation•Gallbladder Hypomotility

Question 10

What is this showing?

Answer 10

Abetalipoproteinemia-The small bowel mucosa shows the characteristic clearenterocytes(due to lipid accumulation).

Question 11

What is abetalioproteinemia?

Answer 11

Abetalipoproteinemia, orBassen-Kornzweig syndrome, is a rareautosomal recessivedisorder that interferes with the normal absorption of fat and fat-soluble vitamins from food. It is caused by a mutation inmicrosomal triglyceride transfer proteinresulting in deficiencies in the apolipoproteins B-48 and B-100, which are used in the synthesis and exportation ofchylomicronsandVLDLrespectively. It is not to be confused withfamilial dysbetalipoproteinemia.

Question 12

How does abetalipoproteinemia present?

Answer 12

The signs and symptoms of abetalipoproteinemia appear in the first few months of life (because pancreatic lipase is not active in this period). They can include failure to gain weight and grow at the expected rate (failure to thrive); diarrhea; abnormal star-shaped red blood cells (acanthocytosis); and fatty, foul-smelling stools (steatorrhea). The stool may contain large chunks of fat and/or blood. Other features of this disorder may develop later in childhood and often impair the function of the nervous system. They can include poor muscle coordination, difficulty with balance and movement (ataxia), and progressive degeneration of theretina(the light-sensitive layer in the posterior eye) that can progress to near-blindness (due to deficiency of vitamin A, retinol).[3]Adults in their thirties or forties may have increasing difficulty with balance and walking. Many of the signs and symptoms of abetalipoproteinemia result from a severe vitamin deficiency, especially vitamin E deficiency, which typically results in eye problems with degeneration of the spinocerebellar and dorsal column tracts.

Question 13

NOTE:Cholesterol molecules are virtually insoluble in water. Bile acids, because of their unique amphiphatic properties, are able to solubilize cholesterol and phospholipid

Question 14

What is theCholesterol Saturation Index (CSI)?

Answer 14

the ratio of theamount of cholesterol in a given bile sample to the maximal cholesterol micellar-holding capacity of that sample.in vitro,Bile that has a CSI greater than 1 is considered supersaturated

Question 15

Even two people with the same CSI may or may not form cholesterol stones. What are some factors that promote stone formation?

Answer 15

The gallbladder mucosa concentrates bile and secretes mucin glycoprotein, both of which increasecholesterol crystal formation. Changes in the composition of bile, including high cholesterol saturation, increased biliary calcium salts, and an increased deoxycholate content all enhance cholesterol crystallization.Delayed gallbladder emptying also promote stone formation

Question 16

Patient with gall-stones have a delay in gallbladder emptyingNot eating or getting nutrition via an IV is assoicated with cholesterol stones b/c normally food in the duodenum increases the pH enough to cause CCK release which cause gallbladder contraction and spincter of Oddi relaxation to allow bile to enter the blood

Question 17

The following factors have been described as possible riskfactors for gall-stones formation:

Answer 17

1) Defective acidification of gallbladder bile:> pH causes increased risk of precipitation of calcium salts2) Gallbladder stasis: Can produce increase of mucin and interfere with mechanical emptying3) allbaladder hypomotility and mucin hypersecretion4) Decreased response to CCK5) Increased intestinal conversion to deoxycholate

Question 18

What things promote black pigment stone formation?

Answer 18

• Hemolysis - Advancing age - Long term TPN - Cirrhosis

Question 19

Cholesterol gallstones develop when bile contains too much cholesterol and not enough bile salts. Besides a high concentration of cholesterol, two other factors are important in causing gallstones. The first is how often and how well the gallbladder contracts; incomplete and infrequent emptying of the gallbladder may cause the bile to become overconcentrated and contribute to gallstone formation. This can be caused by high resistance to the flow of bile out of the gallbladder due to the complicated internal geometry of the cystic duct. The second factor is the presence of proteins in the liver and bile that either promote or inhibit cholesterol crystallization into gallstones. In addition, increased levels of the hormoneestrogen, as a result ofpregnancyorhormone therapy, or the use of combined (estrogen-containing) forms ofhormonal contraception, may increase cholesterol levels in bile and also decrease gallbladder movement, resulting in gallstone formation.

Answer 19

Cholesterolstones vary from light yellow to dark green or brown or chalk white and are oval, usually solitary, between 2 and 3cm long, each often having a tiny, dark, central spot. To be classified as such, they must be at least 80% cholesterol by weight (or 70%, according to the Japanese- classification system). Between 35% and 90% of stones are cholesterol stones

Question 20

Bilirubin(“pigment”, “black pigment”) stones are small, dark (often appearing black), and usually numerous. They are composed primarily of bilirubin (insoluble bilirubin pigment polymer) andcalcium(calcium phosphate)saltsthat are found in bile. They contain less than 20% of cholesterol (or 30%, according to the Japanese-classification system). Between 2% and 30% of stones are bilirubin stones

Question 21

What are the clinical risk factors for black pigment gallstone disease?

Answer 21

-decreases in bilirubin solubilizers (chronic liver disease, age)-increases in bilirubin secretion (chronic hemolysis, TPN, chronic liver disease, Crohn’s disease, age)Gallbladder stasis

Question 22

Mixed (“Brown Pigment”) stones typically contain 20–80% cholesterol (or 30–70%, according to the Japanese- classification system). Other common constituents arecalcium carbonate,palmitatephosphate, bilirubin and otherbile pigments(calcium bilirubinate, calcium palmitate and calcium stearate). Because of their calcium content, they are oftenradiographicallyvisible.They typically arise secondary to infection of the biliary tract which results in the release ofβ-glucuronidase(by injured hepatocytes and bacteria) which hydrolyzes bilirubin glucuronides and increases the amount of unconjugated bilirubin in bile. Between 4% and 20% of stones are mixed

Question 23

What are the risk factors for formation of brown stones?

Answer 23

–Infection, primary biliary, prior surgery–Decreasing biliary secretory IgA–High activity of B-glucuronidase

Question 24

What is biliary colic?

Answer 24

Biliary colic, also known as agallbladder attack, is whenpain occurs due to agallstonetemporarily blocking thebile duct. Typically the pain is in the right upper part of theabdomenand it canradiateto the shoulder. Pain usually lasts from one to a few hours. Often it occurs after eating a heavy meal or during the night.Repeated attacks are common

Question 25

What is acute chlecystitis?

Answer 25

Cholecystitisisinflammationof thegallbladder due to stone blockage. Symptoms includeright upperabdominal pain, nausea, vomiting, and occasionally fever. Oftengallbladder attacks(biliary colic) precede acute cholecystitis. The pain, however, lasts longer than a typical gallbladder attack. Without appropriate treatment, recurrent episodes of cholecystitis are common.Complications of acute cholecystitis includegallstone pancreatitis,common bile duct stones, orinflammation of the common bile duct

Question 26

What is choledocholithiasis?

Answer 26

Common bile duct stone, also known ascholedocholithiasis, is the presence of gallstones in thecommon bile duct(thuscholedocho-+lithiasis). This condition causesjaundiceand liver cell damage, and requires treatment by cholecystectomy and/or ERCP

Question 27

How does choledochlolithiasis present?

Answer 27

Murphy’s signis commonly negative onphysical examinationin choledocholithiasis, helping to distinguish it from cholecystitis. Jaundice of the skin or eyes is an important physical finding in biliary obstruction. Jaundice and/or clay-colored stool may raise suspicion of choledocholithiasis or even gallstone pancreatitis.If the above symptoms coincide withfeverand chills, the diagnosis of ascending cholangitis may also be considered.Greater than 70% of people with gallstones are asymptomatic and are found incidentally on ultrasound. Studies have shown that 10% of those people will develop symptoms within five years of diagnosis and 20% within 20 years

Question 28

What is ascending cholangitis?

Answer 28

Ascending cholangitis, also known asacute cholangitisor simplycholangitis, is aninfectionof thebile duct(cholangitis), usually caused bybacteriaascending fromits junctionwith theduodenum. It tends to occur if the bile duct is already partially obstructed bygallstones

Question 29

What is cholestasis?

Answer 29

Cholestasisis a condition wherebilecannot flow from theliverto theduodenum. The two basic distinctions are an obstructive type of cholestasis where there is a mechanical blockage in the duct system that can occur from agallstoneormalignancy, and metabolic types of cholestasis which are disturbances in bile formation that can occur because ofgenetic defectsor acquired as a side effect of many medications.

Question 30

How does biliary pancreatitis occur?

Answer 30

Reflux of bile into the pain panreatic duct in the presence of a gallstone can activate pacnreatic enzymes

Question 31

What are some extrahepatic (mehcanical) causes of cholestasis?

Answer 31

•stones, malignancy, large ducts primary sclerosing cholangitis, post-surgical complications, chronic pancreatitis, other

Question 32

What are some intrahepatic (metabolic) causes of cholestasis?

Answer 32

•primary biliary cirrhosis, medication, malignant infiltration, small ducts primary sclerosing cholangitis, other

Question 33

Impaired bile formation and bile flow (aka cholestasis)can gives rise to what?

Answer 33

accumulation of bile pigment in the hepatic parenchyma

Question 34

What is this?

Answer 34

Primary Sclerosing cholangitis-Chronic cholestatic disease of the intrahepatic and extrahepatic bile ducts

Question 35

80% of patients with Primary Sclerosing Cholangitis have concomitant _______

Answer 35

inflammatory bowel disease

Question 36

Patients with PSC are on risk for developing _______

Answer 36

bile duct malignancy (cholangiocarcinoma)

Question 37

What is this showing?

Answer 37

Likely Cholangiocarcinoma

Question 38

Describe cholangiocarcinomas

Answer 38

Cholangiocarcinomaorbile duct canceris a form ofcancerthat is composed ofmutatedepithelialcells (or cells showing characteristics of epithelialdifferentiation) that originate in thebile ductswhich drainbilefrom theliverinto thesmall intestine.3 % of all GI malignanciesMost frequent in men at 50-70 years old

Question 39

What are the risk factors for developing cholangiocarcinoma?

Answer 39

Primary sclerosing cholangitis,Hepatitis C related cirrhosis,infection with liver flukes (clonorchis)

Question 40

Pts with cholangiocarcinoma ma have high serum levels of _____

Answer 40

CA 19-9

Question 41

What are the two patterns of gallbladder carcinoma?

Answer 41

-infiltrating-exophytic

Question 42

What is this?

Answer 42

Infiltrating Carcinoma of the Gallbladder•More common and usually appears as a poorly defined area of diffuse mural thickening and induration.•Deep ulceration can cause direct penetration into the liver or fistula formation to adjacent viscera into which the neoplasm has grown.

Question 43

What is this?

Answer 43

Exophytic gallbladder carcinomaGrows into the lumen as an irregular, cauliflower mass, but at the same time invades the underlying wall

Question 44

What is this?

Answer 44

Porcelain Gallbladder•Rare, caused by extensive dystrophic calcification within the gallbladder wall notable for a markedly increased incidence of associated cancer

Question 45

20 % of patients with chronic pancreatitis will present with biliary obstructionClinical presentation is with a cholestatic pattern of liver enzymes in the presence of chronic pancreatitisTreatment is biliary stent placement and/or surgery