Hypofibrinogenemia is a pathological condition characterized by a decrease in the content of fibrinogen in the blood below 2 g / l. Fibrinogen is the main protein of the hemostasis system; a thrombus is formed from it, which stops bleeding when the vascular wall is damaged. Hypofibrinogenemia is clinically manifested by hemorrhagic syndrome and can develop as a result of complications of pregnancy, against the background of the administration of drugs, with severe liver diseases, etc. The level of fibrinogen is examined in the blood plasma as a component of the coagulogram along with INR, APTT, thrombin time. Correction of this condition is carried out by introducing fresh frozen plasma and eliminating the etiological factor.
According to the nature of origin, hypofibrinogenemia can be divided into:
Physiological and pathological hypofibrinogenemias are also distinguished. The only physiological cause is the neonatal period. In the first days of life, the protein-synthetic function of the liver is just beginning to form, so the fibrinogen rate for newborns is lower than in adults, and ranges from 1.25 g / l. All other types of hypofibrinogenemia are pathological.
The most common cause of hypofibrinogenemia is liver disease. The liver is the only organ that synthesizes the main proteins of blood plasma, including fibrinogen. In severe liver damage, already at the stage of liver failure, when massive destruction of hepatocytes (cytolysis) occurs, protein production stops in it. This can be observed in the following pathologies:
Another fairly common cause of hypofibrinogenemia is an extremely severe and life-threatening condition - disseminated intravascular coagulation syndrome (DIC), or rather, its hypocoagulable stage. DIC is a disorder in which generalized thrombus formation occurs in the initial phase.
Excess formation of blood clots leads to a sharp increase in the consumption of clotting factors, including fibrinogen. As a result, the blood loses its ability to clot, bleeding develops, often fatal. Diseases and pathological conditions that cause DIC:
With a normal pregnancy, some changes occur in the hemostasis system, and the level of fibrinogen may rise above normal (physiological hyperfibrinogenemia). However, with various complications associated with the period of pregnancy, the concentration of fibrinogen decreases. Hypofibrinogenemia in pregnant women may indicate the following conditions:
In rare cases, hypofibrinogenemia may be due to mutations in the genes encoding fibrinogen synthesis. Such pathologies include hereditary afibrinogenemia (complete absence of fibrinogen) and hypodysfibrinogenemia (abnormal structures of fibrinogen in combination with a decrease in its production). In most cases, there are either no clinical symptoms at all, or minor hemorrhagic elements on the skin in the form of petechial rashes are observed. However, cases of paradoxical thrombosis in such patients are also known.
Under the influence of certain drugs used in the treatment of acute myocardial infarction, ischemic stroke, and other types of thrombosis, the concentration of fibrinogen in the blood may decrease. This group of medicines is called fibrinolytics. They are divided into 2 main subgroups, causing the dissolution of the formed blood clots. Plasminogen activators convert inactive plasminogen into active plasmin, which stimulates the lysis of fibrin strands (thrombolysis). Profibrinolysin activators act on the endogenous fibrinolytic system of the body. All these drugs can cause hypofibrinogenemia and bleeding.
Since the cause of hypofibrinogenemia can be very serious and life-threatening conditions, its detection requires immediate medical attention. If a liver pathology is suspected, attention is paid to the color of the skin and mucous membranes, and the liver is palpated. Characteristic signs of cirrhosis of the liver are jaundice, ascites, telangiectasia, dilatation of the superficial veins of the abdomen. The skin is examined for the presence of hemorrhagic elements - petechial rashes, ecchymosis, hematomas. Additional research methods are assigned, including:
Blood test for fibrinogen
In the vast majority of cases, the therapy of such patients, due to their serious condition, should be carried out in intensive care and intensive care. Only with asymptomatic forms of dysfibrinogenemia, no treatment is required. Determination of the tactics of managing patients, selection of drugs, their dosage, duration of use is carried out only by the attending physician strictly individually. The leading direction of treatment is the relief of bleeding and the prevention of their occurrence. Methods of conservative therapy for hypofibrinogenemia:
In addition to the direct correction of hypofibrinogenemia and the fight against its hemorrhagic complications, the treatment of the underlying disease plays an important role. Patients with alcoholic hepatitis are strictly forbidden to take alcohol; in case of drug-induced hepatitis, the hepatotoxic medication is urgently stopped. Depending on the etiology, the following drugs are used:
Since hypofibrinogenemia is often a sign of an extremely unfavorable course of pregnancy, emergency delivery by caesarean section is performed for health reasons. If there is uncontrollable uterine bleeding, a complete removal of the uterus (hysterectomy) is performed. When a dead fetus is in the uterus, an operation is performed to extract it.
Some patients with severe forms of dysfibrinogenemia, accompanied by massive bleeding, need constant transfusions of blood components (plasma, cryoprecipitate). Therefore, they have a high risk of infection with hepatitis B, C, HIV. In China, a recombinant human fibrinogen with FIBROAAS dual virus-inactivation has been developed and is undergoing clinical testing. This drug can become an alternative to continuous blood transfusions. However, according to the results of some researchers, the use of human fibrinogen is associated with an increased risk of thrombosis. Therefore, its use is possible only with regular laboratory monitoring of the parameters of the hemostasis system.
The main causes of hypofibrinogenemia are severe diseases, often fatal. Therefore, the prognosis for most patients is poor. A benign course is characteristic only for asymptomatic forms of hereditary dysfibrinogenemia. Despite this, timely diagnosis and competent treatment can lead to a more favorable outcome, and even to recovery.