The more precise the total amylase
Total blood amylase consists of two fractions: pancreatic and salivary. Therefore, its increase is possible not only with pancreatitis, but also with mumps, diseases of the salivary glands, and sometimes with tumors of the lungs and ovaries. Determining the pancreatic fraction specifically removes this uncertainty and significantly increases the specificity of diagnosis. The indicator increases in the first hours of acute pancreatitis, reaching a maximum after 12–24 hours, and normalizes within 3–5 days. In chronic pancreatitis with severe atrophy of the gland, amylase, on the contrary, may be reduced - this is a sign of loss of functioning tissue.
Why preparation is so important
The laboratory result is a number, but the correct number can only be obtained if the rules are followed. Eating changes the levels of glucose, lipids and a number of enzymes significantly; physical activity the day before increases CK and AST; smoking affects hormones; time of day is critical for cortisol and testosterone.
Therefore, a “bad analysis” often turns out to be a consequence of impaired preparation, and not an illness, and leads to unnecessary examinations and prescriptions.
General rules for donating blood
- on an empty stomach 8–12 hours, you can drink water
- Eliminate alcohol and intense exercise per day
- no smoking in an hour
- donate blood before physiotherapy, x-rays and massage
- Take medications in advance by agreeing with your doctor
- for hormones in women, take into account the day of the cycle
How to read the result
Reference values depend on the method and equipment of the laboratory, so it is correct to compare results only within the same laboratory. A deviation of a few percent from the normal limit in itself rarely matters - the overall picture and dynamics are important. It is up to the physician to interpret the analysis: an isolated indicator without a clinical context is often misleading.