Fibrinogen - norm and pathology

In the study of the blood coagulation system, this indicator is determined necessarily. It is important in different situations. Before operations, when preparing for childbirth, with cardiovascular and inflammatory diseases in the blood always determine fibrinogen. Its norm is not the same for adults and newborns. For pregnant women, its upper limit is much higher. But we will dwell on the norms a bit later. First, let's talk about what in general is fibrinogen.

By its chemical structure, it is a protein. It is also called the coagulation factor I. It participates in the final stage of blood clotting, namely, in the formation of a blood clot. In a healthy person fibrinogen in the blood is present in the dissolved state.

In the case of activation of the coagulation system, at its first stage, thrombin is formed under the action of a number of other coagulating factors.

At the second stage of clotting, fibrinogen under the influence of thrombin is split and converted into insoluble fibrin, which serves as the basis of the blood clot, thrombus. Stopping bleeding is associated with it. Hence the meaning that fibrinogen has for the body becomes clear. The norm of this substance for an adult healthy person corresponds to 2-4 g / l. In newborn children, the norm is less - 1,25-3 g / l. But in pregnancy, it rises to 6 g / l. This is understandable. After all, the woman's body is prepared for childbirth, which is always associated with bleeding. Thus, it turns out that the norm of fibrinogen in the blood is not the same for everyone. For pregnant women, it is much higher.

"Yes, but where does it come from?" You ask. It turns out that this coagulating factor is formed in the liver and cells of the reticulo-endothelial system. Therefore, for liver diseases, for example, in severe hepatitis or cirrhosis, fibrinogen, whose norm is not lower than 2 g / l, sometimes decreases to very small digits. This can lead to various bleeding, hemorrhages on the skin and mucous membranes. The intake of certain drugs (androgens, anabolics) can also reduce its level. In some cases, there are congenital disorders of the formation of factor I. This is called afibrinogenemia or hypofibrinogenemia.

A sharp decrease in fibrinogen is observed in the second-third phase of the syndrome of desymminous intravascular coagulation. This severe pathological condition, often resulting in heavy bleeding, is associated with the formation of fibrin clots scattered through small vessels. There are so many of them that the stores of fibrinogen are depleted. Acute fibrinolysis, a process associated with increased dissolution of fibrin, is also accompanied by a decrease in fibrinogen. It decreases with chronic myelogenous leukemia, with a deficiency in the body of vitamins B12 and C.

In some diseases, on the contrary, there is increased fibrinogen. The norm of the largest value of this coagulating factor is 4 g / l. But with rheumatism, infectious diseases, inflammatory processes, oncological diseases, heart attacks and thromboses, the level of factor I can increase by 1.5-2.5 times. Fibrinogen is also called the protein of the acute phase, since its rise accompanies acute inflammatory diseases. Increases the level of this protein in injuries, taking oral contraceptives and estrogens, after surgery.

There is evidence that an elevated level of fibrinogen can precede the onset of strokes and heart attacks. During the research, a clear relationship between these diseases and its previous elevated level was found.

To determine the level of fibrinogen, you need to pass on an empty stomach blood from the vein. Blood is taken in a test tube with an anticoagulant.