Fibrinogen is one of the blood proteins involved in the process of its coagulation. You can see the value of this indicator in a coagulogram - the result of an analysis for blood clotting. The norm of fibrinogen for a he althy adult ranges from 1.5 to 5 grams per liter of blood. What kind of protein is it, what are its functions and how the norms vary, you will learn from our article.
Fibrinogen in the human body
Fibrinogen is synthesized by liver cells and enters the bloodstream along with other proteins. It is colorless, easily soluble in liquids and has a large mass. In addition to being much heavier than other proteins, fibrinogen is capable of creating blood clots, so an increased amount of it affects another analysis, namely ESR (erythrocyte sedimentation rate). If fibrinogen is above normal, ESR will increase.
At the same time, this protein easily penetrates into the extravascular space, is located in the lymph and connective tissues. With severepathologies, its amount outside the blood can reach 80% of the total volume in the body.
We have already talked a little about the norms of fibrinogen. The content of this protein in the blood of he althy people is highly stable, its amount does not change depending on the time of day, sex and age of people. The exceptions are newborns and pregnant women, the rates are slightly increased in the elderly.
Fibrinogen is characterized by a high rate of renewal in the body, the half-life is three days. From 1.5 to 5 grams of protein is produced daily. And in a day, the body is able to renew up to a third of the total volume present.
Fibrinogen functions
Fibrinogen performs its physiological function after interacting with another protein, thrombin, which destroys it and turns it into fibrin. Fibrin molecules are a kind of protein strings that combine into a fine mesh in which erythrocytes become entangled. As a result of these transformations, a blood clot appears - a thrombus that closes the damaged vessel. Thus, fibrinogen is involved in the processes of stopping bleeding and restoring damaged tissues.
Fibrinogen also performs a protective function, preventing the penetration of infections through wounds. Thus, it becomes clear that a sharp decrease in fibrinogen contributes to the development of bleeding.
In addition, the amount of protein affects the work of red blood cells, subject to the norm of fibrinogen in the blood, they are most capable of delivering oxygenand nutrients to the internal organs of the body.
Features of a blood test for fibrinogen
Fibrinogen is most often a part of a comprehensive analysis of blood coagulability - a coagulogram. Now it is often also called a hemostasiogram. It's the same study.
Determination of fibrinogen concentration is carried out most often by the Clauss method with an excess of thrombin. In such a system, the clot formation time depends only on the concentration of active fibrinogen in the sample.
Concentration is determined in plasma obtained from venous blood. Before the study, the sample can be stored for 4 hours at room temperature, 8 hours in the refrigerator, so the analysis is carried out on the day of blood sampling. If a quick result is important to you, you can contact a private laboratory.
Blood for hemostasis is taken from a vein into a vacuum tube with sodium citrate. The standard color designation is a blue cap. It will be useful to observe the sampling process on your part. The fact is that for most samples it is important to invert the tube several times after blood sampling in order to mix the blood with the reagent. For blood for hemostasis, shaking is prohibited, it can lead to a strong distortion of the result of the analysis.
You can also ask how the research will be done. It is possible to conduct a manual study by a laboratory specialist, semi-automatic (when a person prepares the sample, and examines the device) and a study on an automatic analyzer without human intervention. The third one is the most accurate.option. And if you doubt the results of your analysis, then it is best to contact an institution that has an automatic coagulometer.
Preparing for analysis
An analysis for hemostasis is taken from a vein, in the morning, on an empty stomach.
- After eating, 8 to 14 hours should pass.
- Don't smoke for at least 40 minutes before donating blood.
- It is forbidden to drink alcohol the day before.
- Exercise and stress should be avoided an hour before the analysis.
Some medications also affect the result of the analysis. Their reception is either stopped, or it is reported to the doctor who gave the referral for the study:
- heparin;
- estrogen, androgen, oral contraceptives;
- steroid drugs;
- asparaginase;
- valproic acid;
- fish oil.
Fibrinogen test: norms
As already noted, the stability of the amount of protein in the blood does not give a big run-up in the range of its norm. Minor deviations are allowed depending on the age of the patient and during gestation during pregnancy.
- Newborns - 1.3-3 g/l.
- Children under 7 years old - 1.5-4 g/l.
- Men and women 2-4 g/l.
- Elderly 3-6g/l.
Normally, a blood test for fibrinogen is prescribed: before surgery, for cardiovascular diseases, for liver diseases, for suspected inflammation of the internal organs and for monitoring the course of pregnancy.
Normal during pregnancy
Fibrinogen levels in pregnant women increase in the third trimester. This is due to the preparation of the body for natural labor and the prevention of large blood loss during it.
The amount of fibrinogen in the blood greatly affects the course of pregnancy, so in each trimester its level is carefully monitored. The norms are indicated in the table.
| Obstetric gestational age in weeks | Minimum allowable fibrinogen concentration, g/l | Maximum allowable concentration of fibrinogen, g/l |
| 1-13 | 2, 12 | 4, 33 |
| 13-21 | 2, 90 | 5, 30 |
| 21-29 | 3, 00 | 5, 70 |
| 29-35 | 3, 20 | 5, 70 |
| 35-42 | 3, 50 | 6, 50 |
Elevated fibrinogen during pregnancy
Usually, in the first trimester, the level of fibrinogen in women (see the norms above) decreases due to the consequences of the toxicosis experienced. In the second, it begins to grow again and by the end of the third reaches its maximum values - from 4 to 6 g / l of blood. Higher rates entail complications in the form of blood clots in the umbilical cord, spontaneous abortion, detachment of the normal placenta and preeclampsia. Any treatment in such a situation is prescribed only by the gynecologist and gemologist leading the pregnancy.
Reduced fibrinogen atpregnancy
The reverse situation is no less dangerous. Since fibrinogen is responsible for blood clotting, its deficiency can lead to heavy bleeding during childbirth and even death. The level of fibrinogen in the blood below the norm in women usually accompanies severe forms of late toxicosis and DIC. With the right medical intervention, this can be corrected. The main thing is to take the necessary measures in time, and for this, to undergo examinations in a timely manner.
Increased fibrinogen in the human body
If the level of fibrinogen in the blood is above normal, what does it mean? Fibrinogen is often referred to as the acute phase protein in medicine. This means the following: in acute conditions, dangerous lesions of internal organs, the human body directs all its forces to their cure. In particular, a large amount of fibrinogen is released into the blood - a protein responsible for tissue repair, for stopping bleeding.
Thus, with a significant excess of the norm of fibrinogen in the blood, the presence of an acute phase of the disease is assumed. It is further determined by accompanying symptoms and tests.
Deviation upward from the accepted norm of fibrinogen may not be the result of any disease, but an autoimmune disease (that is, a violation in the body directed against itself). The consequences of such an increase can be thrombosis and thrombophlebitis, that is, blockage of blood vessels by blood clots.
Reduced fibrinogen in the human body
The norm of fibrinogen in the bloodmay be underestimated due to both congenital and acquired diseases. The cause can be not only blood diseases, but also the organ responsible for the production of fibrinogen, the liver.
The consequence of its lack in the blood is its increased liquefaction and a tendency to bleed. Blood with an insufficient amount of fibrinogen cannot fully perform its function. Less oxygen enters the internal organs, bacterial and viral attacks are worse experienced. Even minor injuries can lead to profuse bleeding, and the result of serious injuries is death due to the loss of a critical volume of blood.
The causes of reduced fibrinogen can be various blood diseases, such as hemophilia, DIC, myeloid leukemia, polycythemia, blood cancer. Of the acquired diseases, liver diseases lead to a decrease in its level. Also, hypofibrinogenemia can be the result of postoperative and postpartum complications, a significant lack of B and C vitamins, and extensive burn injuries.
Recommendations
For complex diseases, drug therapy is prescribed by the attending physician. In agreement with him, a change in diet is allowed to reduce or increase the level of fibrinogen in the blood.
To reduce the level of fibrinogen in the blood, the most affordable way is to adjust the amount of protein in the diet. It is believed that eating fatty fish or fish oil, foods rich in vitamins B12 and C, lowers fibrinogen, recommend eating acidic berries such as raspberries, lingonberries. Apart froma large number of vitamins in raspberries contain natural acetylsalicylic acid, which thins the blood.
Have a good effect on reducing the level of fibrinogen, and on the whole body as a whole, additional physical activity.
The same can be said about low fibrinogen. Depending on the cause, drug therapy is prescribed by a doctor, after consulting with him, you can adjust your diet and help the body.
Foods that increase fibrinogen levels include buckwheat and other grains, soy, potatoes, cabbage, bananas, spinach, walnuts and eggs.
Remember that all he alth problems can be solved using an integrated approach. When receiving information, do not self-medicate, it is better, being already aware of the nuances, to develop the right treatment strategy together with the doctor. Take care of yourself and stay he althy.
