Enzymes - clinical chemistry
Present in liver, bone, intestine, kidney, neutrophils and placenta.
80% originates from bone.
If GGT up, ALP from liver.
If GGT normal, ALP from bones.
ALP rises with obstruction to the biliary tract.
Most present in the liver, but also found in other tissues.
Very high levels suggest, viral hepatitis, diabetes, congestive heart failure, liver damage, bile duct problems, infectious mononucleosis or myopathy.
Present in liver, heart, skeletal muscle, kidneys, pancreas, lungs, leukocytes and erythrocytes.
Increased levels may indicate haemolytic anaemia, rhabdomyolysis, increased leucocyte count etc
Distinction in source can be made via CK and Troponin.
AST>ALT = hepatocyte necrosis - poor prognosis (AST is found in the mitochondria, not spilled out until severe destruction) - CONSIDER MUSCLE SOURCE
Greater than 2 = Hepatitis.
Less than 2= cholestatic disorder.
Found in both hepatocytes and biliary epithelial cells.
Sensitive for hepatobiliary disease.
5 times increase = good marker of alcohol abuse.
GST (Gluthathione S-transferase):
Isoenzymes of GST are involved in the detoxification and conjugation of several electrophilic compounds with glutathione.
Found to be a very good marker of acute hepatocellular damage with a half life of 90min. Not widely used.
Found in heart, brain, skeletal muscle and other tissue.
Released when muscle damage.
Causes range from exercise injury to hormonal disorders.
Found in muscles, liver, heart, pancreas, kidneys, brain and blood cells.
Used to used to diagnose and monitor heart attacks.
Five types of isoenzymes can help determine location of damage.
LDH-1 - heart, red cells, kidney, germ cells.
LDH-2 - heart, red blood cells, kidney (lesser amounts than LDH-1).
LDH-3 - lungs and other tissues.
LDH-4 - white blood cells, lymph nodes; muscle, liver (smaller amounts than LDH-5).
Highly specific marker for myocardial infarction or muscle cell death.
Also used to diagnose other conditions which relate to cardiac muscle injury.
Found in blood, gastric juices, pancreatic secretions, intestinal juices and adipose tissues.
Acute pancreatitis, pancreatic neoplasia, pancreatic abscesses, and pancreatic duct obstruction can result in high levels of lipase and usually are 2 to 3 times the upper limit of normal.
Is made by the pancreas and by the glands in and around the mouth/throat.
Catalyses hydrolysis of starch
High amylase may indicate the presence of a condition affecting the pancreas.
In acute pancreatitis the levels are 4-6 times normal and remains high until treated.
Chronic pancreatitis, levels will be high but will decrease until problem is solved.
Prostate cancer - raised in 80% of cases presenting with metastases.
