Liver and pancreas study guide

Bilirubin becomes soluble/excreted

Bilirubin is produced from the breakdown of hemoglobin in red blood cells. It is initially insoluble in water; therefore, it is transported to the liver, where it undergoes conjugation, becoming soluble. This conjugated bilirubin is then excreted into bile and eventually eliminated from the body through feces.

urobilinogen, stercobilin, urobilin are formed

• Urobilinogen is formed in the intestines when bilirubin is converted by gut bacteria.

• Some urobilinogen is reabsorbed into the bloodstream and transported to the kidneys, where it is converted into urobilin, which gives urine its yellow color.

• The rest is converted into stercobilin, which gives feces its brown color, thus aiding in the excretion of waste.

What nm is the diazo rxn and bilirubin measured at?

Bilirubin is always measured at 450nm but
Azobilirubin is measured around 575nm

What goes into Dbil testing and Tbil testing

Total (TBil) = Direct (Conjugated) + Indirect (Unconjugated)

DBil is directly measured

Malloy-evelyn method

50% methanol to measure tBil

Jendrassik-Grof method

Caffiene-benzoate-acetate

what are the four interferences for bilirubin?

• Light - breaks down bilirubin

• Room temp- increased degredation

• Hemolysis- decreases the reaction of
  bilirubin with diazo, giving falsely low results

• Lipemia- causes error in spectrophotometric
  readings

Kernicterus

Deposition of unconjugated bilirubin in nuclei of brain and nerve cells causing cell destruction and encephalopathy

Pre-hepatic jaundice causes

Due to a hemolytic process or ineffective erythropoiesis or neonatal jaundice

Pre-hepatic jaundice testing

Hepatic jaundice

actual damage to the hepatocytes

Hepatic jaundice test results

Post hepatic jaundice

blockage of bile flow, cant excrete bilirubin

Post-hepatic jaundice tests

Ammonia testing what does it mean and what does it identify?

Helps with diagnosing Reye Syndrome and evaluates urea metabolism

Contamination of ammonia test is

cigarette smoke, prolonged touniquet use, incorrect sample handling

Budd-Chiari

auto immune disease against many liver antigens,

causes hepatic vein occlusions, leading to fulminant disease

Which enzymes indicate hepatitis?

Elevated ALT and AST levels indicate hepatitis due to liver cell damage.

Which enzymes indicate cholestasis?
Elevated ALP and GGT levels suggest cholestasis from bile flow obstruction

Elevated ALP and GGT levels suggest cholestasis from bile flow obstruction

Wilsons disease

autosomal recessive inherited disorder involving not enough ceruloplasmin

what lab results are seen with wilsons disease

AAT deficiency is caused by

inborn error of protein metabolism resulting in emphysema and liver cirrohsis

What are the lab results for hemochromatosis?

• slightly increased bilirubin, AST, and ALT

• elevated serum iron, ferritin, and transferrin saturation

• hyperglycemia due to pancreatic damage.

What labs would you see with alcoholic cirrhosis

Primary biliary cirrhosis

chronic condition the causes progressive destruction of the intrahepatic bile ducts

What lab results are seen in Primary Biliary Cirrhosis

What symptoms must be present to diagnose Fulminant liver failure

neurological

Crigler-Najjar syndrome type I

• No UDPGT

• billi: 18-40mg/dl

• Kernicterus

Crigler-Najjar syndrome type II

• decreased UDPGT

• Bili: 8-18mg/dl

• kernicterus rare

Gilberts syndrome

• decreased UDPGT and hepatic uptake

• billi: normal 5mg/dl

• increases during fasting, excercise, tylenol

Dubin-Johnson syndrome

Impaired biliary excretion, leading to conjugated bilirubin build up

Rotors syndrome

decreased hepatic uptake and storage, increased levels of unconjugated bilirubin

Obstruction enzymes

ALP, GGT

Hepatoellular enzymes

ALT, AST

Biliary injury- cholestatis leads to

increase of GGT and ALP

Hepatocellular damage (liver disease) leads to

primary increase in ALT and AST

chronic hepatocellular and cholestatic have decrease in

albumin

mild vs. severe is determined by

clotting factors

alpha cells produce

glucagon

Beta cells produce

insulin

delta cells produce

somatostatin

F cells produce

pancreatic polypeptide

What enzymes break down protein

protease

What enzyme breaks down lipids

Lipase

What enzyme breaks down complex carbs

amylase

Zollinger-ellison Syndrome

caused by gastrin-secreting tumors (gastrinomas) leading to excessive gastric acid production, resulting in recurrent peptic ulcers.

Leading causes of acute pancreatitis

• alcohol abuse

• biliary tract disease

What is the best indicator of pancreatitis

Lipase increasing within 4 hrs, peaks at 24, back to normal w/in 8-14 days

What is the second best indicator for diagnosing acute pancreatitis

Amylase

Chronic pancreatitis is caused by

chronic alcohol abuse

subnormal levels of enzymes