2. CLINICAL ENZYMOLOGY
Plasma contains many functional enzymes which are actively secreted into
plasma
Eg:enzymes of blood coagulation
Non functional enzymes coming out from cells of various tissues-normal
wear and tear-normal values in blood are very low but drastically
increased during necrosis/ diseases
Assays of these-helpful to diagnose disease
3. LACTATE DEHYDROGENASE
Enzymes involved in energy production
Found in almost all of the body’s cells > in heart,liver,muscle,kidneys,lungs
and in blood cells. Bacteria also produce-LDH
Convert pyruvate lactate
Reference range 100-200 U/L
Blood
Small amnt seen in serum/plasma
Released into serum –cells are damaged or destroyed
Non specific marker –tissue damage,liver,blood disease or cancer
Fluid
High in CSF-bacterial manenigitis
High-children,strenuous excersice.high in RBC-hemolysis
4. Clinical significance
Blood- indicator of existence and severity of acute or chronic tissue damage
- to detect anemia
Body fluid-distinguish b/w bacterial and viral meningitis
Increased LDH seen in hemolytic anemia,hepatocellular damage,muscular
dystrophy,carcinomas,leukemias and necrosis
Isoenzymes
is a tetramer with 4 subunits –H (HEART) & M (MUSCLE)
Myocardial infarction H4>H1M1
Isoenzymes Subunit orginated from percentage
LDH1 H4 heart muscle 30%
LDH 2 H3M1 RBC 35%
LDH 3 H2M2 Brain 20%
LDH 4 H1M3 Liver 10%
LDH 5 M4 sleletal muscle 5%
5. CREATINE KINASE
Found in heart, brain,skeletal muscle & other tissues
Increased amnt in blood- in muscle damage
Strenous exercise & inflammation of muscle (myositis) –incrase CK
Myopatheis,rhabdomyolysis (breakdown of skeletal muuscle)
Creatine creatine phosphate
Referene range : male 15-1000 U/L ;female 10-80 U/L
Clinical significance
Increased-myocardial infarction,rise within 3-6 hrs of infarction
Muscular dysdrophies -500-1500 U/L
Highly elevated in crush injury,fracture,acute cerebrovascular accidents
6. Isoenzymes
MB isoenzyme estimated in myocardial infarction
isoenzymes subunits Tissue of origin percentage
CK1 BB Brain 1%
CK2 MB Heart 5%
CK3 MM Skeletal muscle 5%
7. ASPARTATE AMINO TRANSFERASE (AST /SGOT)
Also called as serum glutamate oxaloacetate transaminase
Found throughout body mostly,in heart,liver & lesser extend in muscle
Detect liver damage-hepatitis,drugs toxic to liver,cirrhosis or alcoholism
Reference range :8-20 U/L
Clinical significance
Elevated in myocardial infarction
Moderately elevated-liver disease
Marked increase-primary hepatoma
8. Symptoms of elevated AST
Swelling-legs & angles
Tendency-bruice easily (discolouration of skin)
Weakness,fatigue,loss of apetite
Nausea,vomiting
Abdominal swelling/pain
Jaundice
dark urine,light coloured stool
itching
9. ALANINE AMINO TRANSFERASE (ALT/SGPT)
Called as serum glutamate pyruvate transaminase
Found mostly-cells(liver & kidney)
Alanine (amino acid) pyruvate
Reference range :males 13-35 U/L
females 10-30 U/L
Clinical significance
Detect liver injury
Released into blood-liver damage (jaundice)
Very high values (300-1000U/L)-acute hepatitis,either toxic or viral
Moderate increase (50-100U/L)-chronic liver disease –cirrhosis,hepatitis c,non
alcoholic steatohepatitis
10. Symptoms of elevated AST
Swelling-legs & angles
Tendency-bruice easily (discolouration of skin)
Weakness,fatigue,loss of apetite
Nausea,vomiting
Abdominal swelling/pain
Jaundice
dark urine,light coloured stool
itching
11. ALKALINE PHOSPHATASE
Found in several tissue throughout body
Highest con. Seen in bone & liver cells
Elevated alp in blood – liver & bone disorders
Reference range : 40-125 U/L
In Liver
Found in edges of cells that join to form bile ducts,tiny tubes that drain bile
from liver to bowels where it is needed to digest fat in the diet
Increased- one or more bile ducts blocked,inflammation of gall bladder
(cholecystis) or gallstones
Smaller increase-liver cancer & cirrhosis (drugs toxic to liver), hepatitis
12. In Bone
Produced by special cells- osteoblasts
Children and adolscents –higher blood alp bcoz their bones are still growing
Clinical significance
Increased alp-liver damage or a condition increasedbone cell activity
Moderate increase (2-3 times)-hepatic disease (infective hepatitis,alcoholic
hepatitis or hepatocellular carcinoma)
High level (10-12 times)- obstructive jaundice
Drastically high level (10-25)- bone diseases (Paget’s
disease,rickets,osteomalacia,metastatic carcinoma of bone &
hyperparathyroidism)
Decrease level- blood transfusion,heart bypass
surgery,hypophosphatasia,Wilson disease (accumulation of Cu)
13. Isoenzymes
Alpha 1 alp-syn by epithelial cells of biliary canaliculi,increased-obstructive
jaundice
Alpha 2 heat labile alp – syn – hepatic cells
Alpha 2 heat stable alp – placental origin;found in normal pregnancy in
blood;found in circulation abt 15% in case of carcinoma of lung, liver & gut
Pre beta alp-syn –bone;elevated in bone disease
Gamma alp-syn-intestinal cells;increased in ulcerative colitis
Leucocyte alp-decrease in chronic myeloid luekemia;increased in lymphomas
14. GAMMA GLUTAMYL TRANSFERASE (GGT)
Found throughout body-increased con in liver
Elevated in blood-damage to liver or bile ducts
Seen in kidney,pancreas,intestinal cells & prostate gland
Used in syn of glutathione
Reference range : 10-30 U/L
Clinical significance
Moderately increased-infective hepatitis & prostate cancer
First liver enzyme to rise-bile ducts become obstructed (tumors or stones)
Increased –small amnts of alcohol consumption (binge drinkers)
Increase in congestive heart failure, diabetes or pancreatitis
