Liver, Gallbladder, and Pancreatic Function and Disease

Choleithiasis

Gall Stones

Cholecystitis

Inflammation of the gall bladder

What are the three steps of Gall Stone formation?

1. saturation of bile with cholesterol

2. crystal formation

3. hypomotility allowing for growth of crystals

List some causes of stone formation

• genetics

• decreased secretion of bile acids to emulsify fats

• decreased reabsorption of bile acids from the ileum

The pancreas is responsible for endocrine functions (insulin/glucagon) but it is also responsible for exocrine function which control hormones by…

secretion and CCK

What does cholecystokinin (CCK) does what?

regulates secretion of pancreatic enzymes (amylase, lipase, and trypsin) into pancreatic fluid

Pancreatitis

Caused by injury or damage to pancreatic cells and ducts, causing leaking of pancreatic enzymes into pancreatic tissue

When does acute pancreatitis occur?

Alcohol abuse

What characterizes acute pancreatitis?

Short duration. Elevated amylase and lipase - return to normal within 5 days

When does chronic pancreatitis occur?

Alcoholism —→ elevated lipase and amylase

Pancreatic carcinoma is the 5th most frequent form of cancer in the US. What percent of patients die within 1 year of diagnosis?

90%

Describe Zollinger Ellison Syndrome

Pancreatic tumor causes over production of gastrin causing gastric hypersecretion

What is cystic fibrosis?

Dysfunction of mucous and exocrine glands throughout the body (lungs and pancreas). The production of thick sticky mucous clogs lungs and obstructs pancreatic secretion

How is Cystic Fibrosis diagnosed?

Sweat Chloride Test

What sweat chloride level is diagnosis for cystic fibrosis?

>60 mmol/L

What method is used to stimulate sweat production during the sweat chloride test?

Pilocarpine iontophoresis (mild electrical current delivers pilocarpine to stimulate sweat glands)

How is sweat collected and for how long during the test?

Collected on gauze after the electrodes is removed

The functions of the liver include…

1. excretion and secretion of bile

2. Biosynthesis and metabolism

3. Detoxification and drug metabolism

Loss of liver results in death within how many hours?

24 hours

What is Bile?

Complex substance containing water, electrolytes, bile acids, cholesterol, phospholipids, and bilirubin

Once bile is secreted by the liver, it is stored where?

In the gall bladder

What does Bile do?

facilitates digestion by emulsifying fats so that they can be absorbed by the digestive tract

Where is bile excreted?

Feces

Check out the last set of flashcards for Bilirubin metabolism, ok

Ok

What is the defect in Gilbert Syndrome?

Mild decreased conjugations of bilirubin because of dec enzymatic activity

What is the defect in Crigler-Najjar Syndrome?

Severe or absent bilirubin conjugation (MOST SEVERE)

What is the defect in Dubin-Johnson Syndrome?

Impaired excretion of conjugated bilirubin into bile. It builds up and binds to albumin in blood (this is Delta bilirubin)

Why do Neonates commonly have elevated unconjugated bilirubin?

1. More bilirubin produced from the breakdown of HgbF

2. Low capacity of albumin to transport unconjugated bilirubin

3. reduced capability of hepatocytes

4. lack of intestinal flora to convert bilirubin to urobilinogen

What is Reye’s syndrome?

Acute encephalopathy with fatty liver degeneration, usually in children

What is major risk for Reye’s syndrome?

Aspirin use during a viral illness (Flu)

What happens to ammonia levels in Reye’s syndrome?

Increased

What liver finding is characteristic of Reye’s syndrome?

Microvesicular fatty change (fatty liver)

What happens to blood glucose levels in Reye’s syndrome?

Decreased

What are common neurologic symptoms of Reye’s syndrome?

Vomiting, confusion, seizures, coma

What happens to AST and ALT in Reye’s syndrome?

Elevated

An overdose of Acetaminophen leads to fatal hepatic necrosis. What is another name for the drug?

Tylenol

What toxic metabolite is responsible for liver damage in acetaminophen overdose?

NAPQI (N-acetyl-p-benzoquinone imine)

What normally detoxifies NAPQI?

Glutathione

Why does liver damage occur in acetaminophen overdose?

Glutathione stores are depleted so NAPQI accumulates and damages hepaocytes

What is the antidote for acetaminophen toxicity? What does it do?

NAC (N-acetylcysteine) - replenishes glutathione

What is the progression from Alcoholic Liver Disease?

Injury progresses to fatty liver to alcoholic hepatitis then to cirrhosis

What is alcohol hepatitis?

Inflammation of the liver due to chronic alcohol use

What is the classic AST:ALT ratio in alcoholic hepatitis?

>2:1 (AST higher)

Why is AST higher than ALT in alcoholic hepatitis?

Alcohol damages mitochondria (AST is mitochondrial) which causes vitamin B6 deficiency (affects ALT more)

What is Cirrhosis?

Irreversible inflammatory disease that disrupts liver function and even structure

How does inflammation cause Cirrhosis?

Biliary channels become obstructed and cause hypertension, the blood becomes shunted away from the liver and necrosis develops