To make a diagnosis, the doctor usually prescribes a variety of tests to help find out the course of the disease. Blood, urine, mucus or other human waste products are subjected to research.
Blood chemistry
Blood testing is performed for almost every disease, because any changes in the composition of the blood can make it easier to diagnose. It is carried out even if the patient does not present any complaints about his he alth. That is why, if you really care about yourself, ask your doctor to periodically refer you to this study. This is especially true for those who have some problems with the heart, liver and kidneys.
What is CPK?
KFK - what is it? The analysis for CPK is one of the components of the general biochemical blood test and is designed to determine the amount of creatine phosphokinase. This substance is usually found in some muscles, in particular, in the skeletal muscles and the heart.
Creatine kinase is a substance that creates from creatine and ATP another substance called creatine phosphate. This compound is consumed during increased physical exertion of the body. Beyond the skeletalmuscle and heart, it is found in the cells of the brain, lungs and thyroid gland.
When CPK readings go up and down?
When muscle fibers are damaged, CPK leaves the cells, and its content in the blood increases significantly. That is why laboratory tests for determining the level of CPK in the blood are reliable with an accuracy of about 100%. They allow the diagnosis of myocardial infarction. After 2-4 hours after the attack, the analysis will show that CPK is elevated, but this indicator quickly returns to normal.
In addition, an increase in CPK can also be observed with physical muscle injuries, crushing and disease, as well as after drinking a significant amount of alcoholic beverages and sleeping pills abuse.
Reduction in this indicator is not observed in the laboratory study.
Features of the analysis
CPK analysis - what is it and how is the procedure carried out? For blood testing for this parameter, the traditional method is used. It consists in the following: from the vein of the forearm (namely, from the upper third of the forearm), the specialist takes a certain amount of blood. After that, the collected blood is sent to the laboratory, where the study is carried out.
Before taking this test, it is advisable for the patient not to eat. So, the result will be more informative and accurate.
To determine the level of CPK, a blood test is carried out by photometry. It is in molecularabsorption spectral study. The techniques included in this examination are based on the absorption of electromagnetic radiation, which occurs in a selective manner. Absorption is produced by the molecules of the component, the level of which is checked in the visible, infrared, and ultraviolet parts of the spectrum. CPK compounds with the reagent may also be absorbed.
A special apparatus is used for the study - a KFK photocolorimeter.
Indications and results
Indications for analysis are:
- early diagnosis of myocardial infarction (analysis is required in the next 2-4 hours);
- differential diagnosis of the state of myocardial infarction, when this attack is combined with a mild or uncomplicated angina attack.
In addition, this test is prescribed for all patients who are being treated for any heart disease in order to exclude the fact of a heart attack. It is the knowledge of the level of CPK (what it is described above) that will help specialists determine the condition of the heart. An increase in this substance in the blood can signal possible heart problems. If this phenomenon is permanent, then the doctor in most cases decides on preventive treatment, which will stop the development of the disease in the future.
blood CPK (what it is, you can find out at the beginning of the article) is elevated in the following cases:
- myocardial infarction (increased values are diagnosed in the first 2-4hours, the maximum is reached in a day; after 3-6 days the value decreases, but normalization does not occur);
- muscle dystrophy;
- Reye's syndrome (acute hepatic encephalopathy);
- shock condition;
- various poisonings, in particular, alcohol and sleeping pills;
- infectious lesions of the myocardium.
Reduced blood CPK level (which is described above) is observed with a decrease in muscle mass, a sedentary lifestyle, and also acts as an indirect sign of the development of thyrotoxicosis (intoxication with thyroid hormones produced by the thyroid gland).
CPK level. Norma
In order to adequately assess the ratio of concentration and total activity of CK, use the calculated relative index. Its formula is as follows:
RI (calculated index)=CK-MB (µg/L) / total CPK (U/l)100
The indicator is calculated as a percentage.
KFK-norm is expressed by the following values:
- < 24 U/l –KFK-MB;
- < 6% of total CPK activity;
- laboratory norm - 10–110 IU;
- in SI units - 0, 60 - 66 mmol/l.
Information related to the reference values (normal) of these indicators, and included in the analysis of indicators in different laboratories may vary. However, the difference between the norms is insignificant, and the disease is diagnosed anyway.
How to prepare for blood donation for CPK analysis?
In order for the results not to be false positive, it is recommended to donate blood on an empty stomach. Drinking allowedpure water without impurities. After eating before donating blood to determine the level of CPK (what it is, described in detail above), at least 8 hours should pass, and the more, the better. If you use any medicines, the analysis is not recommended. This should be done before the start of taking the drugs or two weeks after the end. If it is impossible to stop taking medications in any way, then the laboratory assistant needs to indicate all the drugs that are currently systematically taken by the patient, as well as their dosage.
Another important point to consider before donating blood is playing sports. Before the test itself, it is highly recommended not only to perform active physical exercises, but also to experience stressful situations and drink alcohol even in small doses. In addition, do not rush to donate blood to determine the level of CPK immediately after a fluorography, x-ray examination (even if you took a picture of a tooth or finger), an ultrasound procedure, various physiotherapy procedures, or a rectal examination.
What can affect CPK levels?
There are a number of factors that can affect the results of a blood CPK study, and lead to their distortion:
- high physical activity;
- injection of medications;
- Hilez samples;
- taking a number of medications;
- hemolysis.
Elevated levels of CPK, which is determined by laboratory testing,may indicate changes in the body that are associated with myocardial infarction, rhabdomyliosis, muscle dystrophy, myotosis, excessive physical exertion, as well as surgeries of varying complexity.
If there is a decrease in the level of this indicator, then this has no diagnostic value.
