Enzymes and cardiac markers Flashcards
What is Km?
The substrate concentration at which the rate of reaction is 50% of its maximum
high Km = weak affinity
Where is ALP produces?
Liver
Bone - pagets, osteomalacia, vitamin d def, primary hyperparathyroidism
placenta - pregnancy in last trimester
intestine
- What is an increase in bone ALP caused by?
Increased osteoblast activity
- List some causes of very high ALP (> 5 x upper limit of normal).
Bone – Paget’s disease, osteomalacia
Liver – cholestasis, cirrhosis
- List some causes of moderately raised ALP (< 5 x upper limit of normal).
Bone – tumours, fractures, osteomyelitis
Liver – infiltrative disease, hepatitis
- Describe the ALP levels in osteoporosis.
It is NORMAL unless there is a fracture
Which organs produce AST?
Heart
Liver
Muscle
Kidney
What does a raised ALT indicate?
Hepatitis *not used routinely for the following* Kidney Pancreatitis MI
What does an increased GGT indicate?
Hepatitis
Alcohol
Pancreatitis - not diagnostic (use serum amylase instead)
kidney disease (not used routinely)
What causes a raised LDH?
Lymphoma haemolysis germ-cell testicular cancer myosititis hepatic disease
- Which markers are used in acute pancreatitis?
Amylase
Lipase
- Where else is amylase found?
Salivary glands
NOTE: will be raised in parotitis
- What are the three forms of creatine kinase?
CK-MM = skeletal muscle CK-BB = brain CK-MB = cardiac muscle
- List some other causes of high CK.
Muscle damage - rhabdomyolysis/myositis Myopathy (e.g. Duchenne muscular dystrophy) MI Severe exercise Physiological (Afro-Caribbeans)
- Where are troponins found within cells?
Within the contractile apparatus. Therefore when heart cells are damaged, it is released
