Prostate-specific antigen test

Prostate specific antigen (PSA) is a polypeptide chain glycoprotein with 237 amino acid residues, which is produced by the intracellular plasma vesicles of the prostate squamous epithelial cells. Its relative molecular mass is about 34kD, and its function belongs to a serine trypsin that is a kinin-releasing enzyme. PSA exists in the endoplasmic reticulum of the prostate, the squamous epithelial cells of the prostate, and their secretions. Both normal and diseased prostate tissues contain PSA, and the PSA component of individual cells is relatively stable. PSA can be fused and degraded by α1-antichymotrypsin and α2-macroglobulin. Generally, there is no or only a very small amount of PSA in the blood.

Abnormal results of prostate-specific antigen test in men:

(1) The values ​​of both scattered PSA (F-PSA) and total PSA (T-PSA) in blood cells of prostate cancer patients increased significantly, with the increase of T-PSA being more significant. Therefore, the ratio of scattered PSA to total PSA (F/T ratio) decreased. The F/T ratio can be used to differentiate between prostate cancer and prostate hyperplasia. In particular, when the PSA level is limited to the range of 4-10μg/L, the use of the F/T ratio is better than PSA.

(2) PSA has key clinical performance in the early diagnosis of prostate cancer, clinical medical installment, postoperative efficacy observation and follow-up.

(3) Prostatic hyperplasia (BPH), male prostate infarction, subacute bacterial infection prostatitis, subacute urinary tract obstruction, etc. can also cause an increase in blood cell PSA levels. Groups that need to be tested: those with symptoms such as frequent urination, urgency, inability to hold urine, urinary retention, urinary pain, inability to produce a urine stream, hematuria, bone pain, etc.

Frequently Asked Questions about Prostate Specific Antigen Test for Men

Before the test: (1) Do not eat greasy or high-protein foods the day before the blood test, and avoid drinking too much alcohol. The alcohol content in the blood will directly affect the test results. (2) After 8 pm the day before the routine physical examination, you should abstain from food for 12 hours to avoid affecting the test results. (3) When the blood test is being drawn, you should release stress to avoid contraction of blood vessels due to fear, which will increase the difficulty of blood collection.

After the examination: (1) After the blood test, you need to press the needle hole for 3-5 minutes to activate the blood circulation. Note: Do not rub it to prevent subcutaneous hematoma. (2) The pressing time should be sufficient. The blood clotting time varies from person to person, and some people need a little longer to clot. Therefore, if the pressure is stopped immediately when the skin surface does not seem to be bleeding, the blood may not be completely activated and may penetrate into the subcutaneous tissue, causing bruises. Therefore, pressing for a longer time can activate the blood circulation thoroughly. If there is a tendency of bleeding, the pressing time should be increased. (3) If symptoms of needle sickness such as dizziness, vertigo, and drowsiness occur after the blood test, you should lie down immediately and drink a small amount of red bean sugar water. After the symptoms are alleviated, you can have a routine physical examination. (4) If local blood accumulation occurs, apply a wet and hot cotton towel to the face after 24 hours to promote digestion and absorption.