Enzymes

Diagnostic value of the Various Enzymes in Diseases

What Sample will you take for enzyme estimation?

• Most of the enzymes are estimated in the patient’s serum.

What precautions will you take to estimate enzyme levels?

1. Avoid hemolysed samples.
2. In the case of lipemic serum, you may get the wrong result.

How will you define enzyme?

1. Enzymes are protein molecules that catalyze chemical reactions without themselves being altered chemically.
2. Each enzyme is specific for a substrate that converts to a defined product.
3. Enzymes are diagnostic for various diseases and give information for the recovery or prognosis.

A summary of various enzymes in diseases.

Disease	Enzyme	Initial rise	Peak level	Back to normal
Acute Pancreatitis	Lipase	4 to 8 hours	24 hours	8 to 14 days
	Amylase	2 to 12 hours	12 to 72 hours	3 to 4 days
Acute Viral hepatitis	SGOT (AST)	before the onset of jaundice	7 to 12 days	3 to 4 weeks after the onset of jaundice
	SGPT (ALT)	before the onset of jaundice	7 to 12 days after the onset of jaundice	3 to 4 weeks after the onset of jaundice
Acute Hepatobiliary Obstruction	ALK.Phosphatase	immediately		When an obstruction is relieved
	Gamma GT (GGT)	Immediately		When an obstruction is relieved
Acute Myocardial Infarction	SGOT (AST)	6 to 8 hours	18 to 24 hours	4 to 5 days
	LDH	8 to 12 hours	24 to 48 hours	7 to 12 days
	CK-MB	4 to 6 hours	12 to 24 hours	after 48 hours
	Creatine Kinase CK	6 to 8 hours	24 to 36 hours	3 to 4 days
	Myoglobin	2 to 3 hours	6 to 9 hours	24 to 36 hours
	Troponin I	4 to 8 hours	14 to 18 hours	5 to 9 days (after 10 days)
	Troponin T	4 to 8 hours	14 to 18 hours	After 14 days (2 to 3 weeks)
Prostate	Prostatic acid phosphatase	Raised in prostatic carcinoma	A significant increase was seen in metastasis

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