Fibrinogen is one of the blood proteins involved in its coagulation process. You can see the value of this indicator in a coagulogram - the result of a blood coagulation test. The rate of fibrinogen for a healthy adult varies 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, together with other proteins, enters the bloodstream. It is colorless, easily soluble in liquids and has a large mass. In addition to the fact that fibrinogen is much heavier than other proteins, it is able to create blood clots, so its increased amount affects another analysis, namely ESR (erythrocyte sedimentation rate). If fibrinogen is higher than normal, ESR will increase.
At the same time, this protein easily penetrates into the extravascular space, located in the lymph and connective tissues. In severe pathologies, its amount outside the blood can reach 80% of the total volume in the body.
We already talked a little bit about fibrinogen levels. The content of this protein in the blood of healthy people is highly stable, its amount does not change depending on the time of day, gender and age of people. The exception is newborns and pregnant women, slightly increased indicators 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 formed daily. And in a day, the body is able to update up to a third of the total volume present.
Fibrinogen function
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, combining into a fine network, in which red blood cells get tangled. As a result of these transformations, a blood clot appears - a blood clot that closes the damaged vessel. Thus, fibrinogen is involved in stopping bleeding and restoring damaged tissues.
Fibrinogen also has 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 maximally able to deliver oxygen and nutrients to the internal organs of the body.
Features of a blood test for fibrinogen
Fibrinogen is most often part of a comprehensive blood coagulation analysis - a coagulogram. Now it is often called also a hemostasiogram. This is one and the same study.
The determination of fibrinogen concentration is most often carried out according to the Clauss method with an excess of thrombin. In such a system, the time of clot formation depends only on the concentration of active fibrinogen in the sample.
The concentration is determined in plasma obtained from venous blood. Before the test, 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 the 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 reverse the tube several times after blood sampling to mix the blood with the reagent. For blood to hemostasis, shaking is prohibited, it can lead to severe distortion of the analysis result.
You can also ask how the study will be performed. It is possible to conduct a study manually by a laboratory specialist, semi-automatic (when a person prepares a sample and examines the device) and research on an automatic analyzer without human intervention. The most accurate is the third option. And if you doubt the results of your analysis, it is best to contact an institution that has an automatic coagulometer.
Analysis preparation
An analysis of hemostasis is given from a vein, in the morning, on an empty stomach.
- After eating, it should take from 8 to 14 hours.
- Before donating blood, you must not smoke at least 40 minutes.
- It is forbidden to drink alcohol the day before.
- An hour before the analysis, physical activity and stress should be avoided.
The analysis result is also affected by some medications. Their reception either stops, 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 fat.
Fibrinogen assay: norms
As already noted, the stability of the amount of protein in the blood does not give a large run in the range of its norm. Slight 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 3-6 g / l.
Normally, a blood test for fibrinogen is prescribed: before surgical interventions, for cardiovascular diseases, for liver diseases, for suspected inflammation of the internal organs, and for monitoring the course of pregnancy.
Norm 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 with it.
The amount of fibrinogen in the blood greatly affects the course of pregnancy, so in every trimester its level is carefully monitored. Standards are indicated in the table.
| Obstetric gestation in weeks | The minimum permissible concentration of fibrinogen, g / l | The maximum permissible 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 |
Increased Fibrinogen in Pregnancy
Usually, in the first trimester, the level of fibrinogen in women (see the norms above) decreases due to the consequences of the tested toxicosis. In the second, it begins to grow again and by the end of the third it reaches 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 normal placenta and gestosis. Any treatment in this situation is prescribed only by a gynecologist and a hemologist conducting pregnancy.
Reduced Fibrinogen in Pregnancy
The reverse situation is no less dangerous. Since fibrinogen is responsible for blood coagulation, its lack can lead to heavy bleeding during childbirth and even death. A level below the normal fibrinogen level 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 timely examinations.
Increased fibrinogen in the human body
If fibrinogen levels are higher than normal, what does that mean? Fibrinogen is often called an acute phase protein in medicine. The following are implied: in acute conditions, dangerous lesions of internal organs, the human body directs all its forces to cure them. 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 fibrinogen norm in the blood, the presence of the acute phase of the disease is assumed. Then it is determined by the accompanying symptoms and analyzes.
A deviation in the direction of an increase from the accepted norm of fibrinogen may not be a consequence 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 thrombi.
Decreased fibrinogen in the human body
The rate of fibrinogen in the blood can be underestimated due to both a congenital disease and an acquired one. The cause may be not only blood diseases, but also the body responsible for the production of fibrinogen, liver.
A consequence of its lack in blood is its increased liquefaction and tendency to bleeding. Blood with insufficient fibrinogen cannot fully perform its function. Less oxygen comes to internal organs, bacterial and viral attacks are worse experienced. Even minor injuries can lead to heavy bleeding, and the result of serious damage is fatal due to the loss of a critical volume of blood.
The causes of decreased fibrinogen can be various blood diseases, such as hemophilia, DIC, myelogenous leukemia, polycythemia, and blood cancer. Of the acquired diseases, liver diseases lead to a decrease in its level. Also, hypofibrinogenemia can be a consequence of postoperative and postpartum complications, a significant lack of B and C vitamins, and extensive burn injuries.
Recommendations
In complex diseases, drug therapy is prescribed by the attending physician. By 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 the consumption of fatty varieties of fish or fish oil, foods rich in vitamins B12 and C is reduced by fibrinogen, and the use of acidic berries such as raspberries and lingonberries is recommended. In addition to a large number of vitamins, raspberries contain natural acetylsalicylic acid, which dilutes the blood.
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 reduced fibrinogen. Depending on the reason, the doctor prescribes drug therapy, after consulting with him, you can adjust your diet and help the body.
Products that increase fibrinogen levels include buckwheat and other cereals, soybeans, potatoes, cabbage, bananas, spinach, walnuts and eggs.
Remember that all health problems can be solved using an integrated approach. When receiving information, do not self-medicate, it is better, being already aware of the nuances, together with the doctor, develop the right treatment strategy. Take care of yourself and stay healthy.