What’s measured
What is PSA?
PSA is the prostate-specific antigen, a proteolytic enzyme produced by the epithelial cells that line the prostatic ducts. Its role is to loosen up semen. A small portion of PSA is excreted into the bloodstream, where it circulates in its free form (10%) or in the A1AT-bound (86% of the total PSA) and the A2MG-bound forms. It is only released into the bloodstream to an elevated extent when the prostate microstructure is disturbed, i.e. in various inflammations and tumours.
Over 1–3 days, only half of the released antigen remains in the bloodstream. Even though the screening of asymptomatic men is disputable since as much as 80% of men with a total PSA over 4 mg/l do not present with prostate cancer, degrees of an elevated PSA concentration correlate with the tumour size and condition.
If your PSA level is elevated, it may signalise the risk of prostate cancer or other prostate-related conditions, such as enlargement or inflammation. It is important to realise that the PSA level usually increases with aging.
A PSA test does not necessarily have to reveal prostate cancer. According to the CaPSURE study, approximately 15% of men with a low PSA level had a prostate carcinoma. It is therefore advisable to discuss your concerns with an expert, while you may also take a comprehensive test – the Prostate Health Index (PHI).
PSA is a protein produced by the cells of the prostate – the largest accessory gland of the male reproductive system. This antigen may be measured in blood and is used as a marker for the detection of potential prostate conditions, including cancer. Elevated PSA levels should be consulted with a doctor and it is necessary to take a check-up examination at a urology clinic.
When is the PSA test recommended:
- during a preventive medical examination;
- when problematic urination is present;
- in case of a positive family history for prostate cancer;
- when prostate cancer is suspected;
- in the therapy monitoring for early detection of a recurrence.
Instructions before collection
We do not recommend entry of patients/clients with clinical signs of disease (temperature, cough, signs of respiratory tract infection, etc.) to undergo this test.
We recommend hand disinfection prior to entry to the clinics/collection points.
It is advised to fast for a minimum of 8 hours by refraining from eating or drinking anything expect water. Faiing to fast before the test may affect result quality. If you are currently on medications, consult your healtcare provider to determine whether you should continue taking them prior to the test.
PREPARATION FOR BLOOD COLLECTION
The recommended time to collect blood is between 7 a.m. and 9 a.m., to obtain comparable results from different blood draws. To assess the numerical test result, so-called reference intervals are used, which are based on morning fasting collections and are used for population comparison. This time interval is also recommended in light of the biological cycles that naturally take place in the body.
GENERAL PRE-SAMPLING INSTRUCTIONS
It is necessary to come to the testing site earlier, so that you can rest in the waiting room for approximately 20 minutes to have a relatively relaxed body and mind.
It is necessary to arrive on an empty stomach for the collection itself, in the case of collections at a later time in the day, at least three hours on an empty stomach. At home, it is desirable to drink a sufficient amount of pure water (at least up to half a liter) - this is important for a successful blood collection. Mineral water, juice, coffee and tea are not recommended.
Herbs included in tea may contain substances affecting the blood count. Coffee and black tea increase gastric acid production and release insulin from the pancreas, thereby affecting glucose metabolism. Since everything in the body is interrelated, they can impact other tests. Another extreme is when your body is running out of fluids. In this case, the number of red blood cells, the level of protein and lipids bound to the protein increase and the level of urea in the blood can also increase. It is therefore advisable to drink pure water when you wake up.
Generally, it is recommended to:
• around 6 p.m. eat only light meals, do not eat fatty food (cheese, butter, cream, meat, smoked meat, bacon) and sweet meals,
• fast for 10-12 hours (Attention: it is not advisable to starve for more than 16 hours!), in the case of later collection (after 9:30 a.m.), a lighter breakfast is allowed, no later than 3 hours before collection,
• drink non-alcoholic beverages and drinks without sugar in the usual quantity, in the case of adult clients 24 hours before blood collection (Alcohol in the blood changes lipid levels, the level of glucose is reduced, uric acid levels increase and liver enzymes are released into the blood),
• take only prescribed medicines in the evening,
• avoid increased physical activity, and strength and endurance exercise the day before blood collection (Lipid, glucose, some enzyme levels in the blood and other parameters may change during physical activity. The recovery of normal values to maintain the accuracy of laboratory results may take a longer time, depending on the duration of the exercise, your physical fitness in general and other factors. We recommend maintaining normal daily physical activity such as light stretching, short cycling to work, gardening, etc.),
• avoid psychological stress, which raises blood glucose levels and causes the release of stress hormones in particular,
• avoid smoking for at least 6 hours prior to blood collection because it increases the level of carbonylhemoglobin produced by the reaction of the blood dye with carbon monoxide and alters the permeability and elasticity of the vessels, affecting the ratios of blood analytes,
• do not chew gum for at least 6 hours before blood collection, as this may affect glucose and enzyme levels,
• do not undergo stressful diagnostic or therapeutic interventions for at least 24 hours prior to blood collection.
If any of the tests you have selected require special preparation, you will be informed of the fact by email with the order and blood collection instructions attached. These specific instructions have priority over the general recommendations for preparation.
MEDICINES
It is recommended to have blood collected before the planned doses of medicines. If it is not possible to take the medicine later, you should inform the nurse during blood collection and specify what medication you have taken.
Take the medicines prescribed by your doctor in the morning or bring them with you to take them after blood collection (thyroid medicines, antihypertensive medicines, blood thinners, contraceptives, etc.) In the case of later collection (after 9:30 a.m.), you can take the prescribed medication in the morning.
Do not take iron, vitamin, nutritional supplements or other supplements, including homeopathics, for at least three (3) days prior to blood collection.
SPECIFIC SITUATIONS
In order to obtain the appropriate answers to your questions with regard to the laboratory tests, it is important to accurately notify the nurse at the healthcare provider about the following facts prior to your blood test:
• regularly used medicines and supplements (ideally come with a written list to the blood collection site),
infectious diseases you suffer from (e.g., HIV, hepatitis, mononucleosis...),
• contact with an infected person or presence in an infectious environment,
• if you have received an infusion within the last 5 days, specify into which limb,
• intramuscular injections within 3 days prior to the blood collection date,
• long-term immobilisation, lost ability to move,
• activities at higher altitudes,
• allergy to common band-aids,
• if you feel unwell when looking at blood or needles, please also notify our blood collection staff of the fact.
OTHER FACTORS
Please note that prolonged use of medication or other important factors may affect the values measured by the tests you have selected. For more information, please see the description of the specific test. To obtain objective test results, take the time to properly prepare for your blood collection.
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