Hemorrhagic disease of the newborn
Hemorrhagic disease of a newborn is a disease of children in the neonatal period, manifested by increased bleeding due to the inadequacy of blood coagulation factors whose activity depends on the content of vitamin K.
What causes hemorrhagic disease of the newborn?
The biological role of vitamin K is the activation of the process of gamma-carboxylation of glutamic acid residues in blood clotting factors: prothrombin (II factor), proconvertin (VII factor), antihemophilic globulin B (IX factor) and Stewart-Prouer factor (X factor); also in proteins C and S of plasma involved in anti-twisting mechanisms; osteocalcin and some other proteins. With a deficiency of vitamin K, inactive liver cells II, VII, IX and X (Protein induced by vitamin K-absence - PIVKA) are formed in the liver, which are unable to bind calcium and fully participate in blood clotting.
Vitamin K penetrates very weakly through the placenta. Primary hemorrhagic disease is due to the fact that the vitamin K content in the fetus is small (not more than 50% of the adult's level). After the birth of vitamin K with breast milk is little, and its active production of intestinal microflora begins with a 3-5-day life of the child.
Factors contributing to primary K-hypovitaminosis in a newborn: prematurity; the appointment of pregnant anticoagulants of indirect action, anticonvulsant drugs, broad-spectrum antibiotics; gestosis; hepato- and enteropathy, intestinal dysbiosis.
With prematurity, the synthesis of polypeptide precursors of plasma factors (PBPF) of blood coagulation in the liver of a child is reduced.
With secondary hemorrhagic disease, the synthesis of PPPF coagulation of blood occurs with liver diseases (hepatitis, atresia of biliary ducts, etc.). There is also a second variant of the development of secondary hemorrhagic disease - a violation of vitamin K synthesis, caused by prolonged parenteral nutrition, malabsorption syndrome or the appointment of antagonists of vitamin K - coumarin and neodicumarin.
At the same time, children with a very low level of vitamin K in the blood and children with a high PIVKA content are detected.
Pathogenesis
Disturbance in the synthesis of SOPs and / or disruption of the carboxylation of glutamic acid residues of the ULP coagulation results in a disruption in the production of factors II, VII, IX and X. This is manifested by prolongation of prothrombin time (PT) and activated partial thromboplastin time (APTT).
Symptoms of hemorrhagic disease of the newborn
The early form of hemorrhagic disease of a newborn is characterized by the appearance in the first days of life of bloody vomiting (haematomesis), pulmonary hemorrhage, hemorrhage into the abdominal cavity and retroperitoneal space, especially often in the adrenal glands, liver, spleen. Hemorrhagic disease of a newborn can begin even in utero, and the child already at birth has intracranial hemorrhages (with neurosonography), cutaneous hemorrhages.
The classical form of hemorrhagic disease is typical for a child on natural feeding and appears on the 3-5th day of life with bloody vomiting, melena (intestinal bleeding), skin hemorrhages (ecchymoses, petechiae), bleeding when the remainder of the umbilical cord, cephalohematoma. In children with severe hypoxia, birth trauma, vitamin K deficiency can be manifested in the form of intracranial hemorrhages, hemorrhages for aponeurosis, as well as internal hematomas and bleeding.
Children with melena may have hyperbilirubinemia due to increased disintegration of erythrocytes in the intestine. The cause of melena is the formation of small ulcers on the mucous membrane of the stomach and duodenum, in the genesis of which the leading role is taken of the excess in the newborn glucocorticoids (due to the birth stress), ischemia of the stomach and intestine. A certain role in the origin of melena and bloody vomiting is played by gastroesophageal reflux and peptic esophagitis.
Clinical symptoms of late hemorrhagic disease of the newborn can be: intracranial hemorrhage (more than 50%), extensive skin ecchymosis, melena, hematemesis, umbilical cord bleeding, hematuria, cephalohematoma.
Complications of hemorrhagic disease of newborns include hypovolemic shock, which is manifested by weakness, pallor, often a drop in body temperature to subnormal figures, a drop in blood pressure.
Classification
Isolate the primary and secondary forms of the disease. Primary hemorrhagic disease of the newborn is due to the fact that the vitamin K content in the fetus is small and after birth, its intake with breast milk is insignificant, and active production of the intestinal microflora begins with the 3-5th day of the child's life. In secondary hemorrhagic disease, a violation of the synthesis of PPP coagulation occurs due to liver disease, prolonged parenteral nutrition, or malabsorption syndrome in a newborn.
In addition, the early form of the disease, characterized by the appearance of bleeding for 1-2 days of life, classic - bleeding for 3-5 days of life and a late, more often secondary, form, in which bleeding can develop on any day of the period of the newborn.
Diagnosis of hemorrhagic disease of the newborn
To diagnose a hemorrhagic disease of a newborn, first examine the time of blood coagulation, the time of bleeding, the number of platelets. Late, or simultaneously, PV, APTTV, thrombin time (TB) and the number of erythrocytes, hemoglobin and hematocrit (for the detection of anemia) are determined.
For hemorrhagic disease, lengthening of the clotting time is typical, with normal bleeding time and the number of thrombocytes. Confirms the diagnosis of lengthening PV and APTT under normal TV.
With significant blood loss, anemia is noted, which, however, fully manifests itself in 2-3 days after bleeding.
Differential diagnostics
Hematemesis and melena in children of the first days of life must be differentiated from the "swallowed maternal blood" syndrome, which occurs in one of the three children who have blood in vomit masses or feces on the first day of life. To do this, use the Apt test: bloody vomit or feces are diluted with water and a pink solution with hemoglobin is obtained. After centrifugation, 4 ml of the supernatant are mixed with 1 ml of a 1% sodium hydroxide solution. The change in the color of the liquid (estimated 2 min.) To brown indicates the presence of hemoglobin A (maternal blood) in it, and the preservation of pink color - about fetal (alkaline-resistant) hemoglobin G, i.e. Blood of the child.
Differential diagnosis is also performed with other coagulopathies (hereditary), thrombocytopenic purpura of newborns and disseminated intravascular coagulation syndrome (DIC syndrome). For this purpose, an unfolded coagulogram and, if necessary, a thromboelastogram are performed.
Laboratory data for the most common hemorrhagic syndromes in newborns
|
Indicators |
The norm for full-term children |
Hemorrhagic |
Hemophilia |
Thrombocytopenia |
DIC- |
|
Clotting time (according to Burker) |
Start - 4 min End - 4 min |
Elongated |
Elongated |
Norm |
Elongated |
|
Bleeding time |
2-4 minutes |
Norm |
Norm |
Elongated |
Elongated |
|
Number of |
150-400x10 9 / l |
Norm |
Norm |
Decreased |
Decreased |
|
PV |
13-16 s |
Elongated |
Norm |
Norm |
Elongated |
|
TV |
10-16 s |
Norm |
Norm |
Norm |
Elongated |
|
APTTV |
45-60 s |
Elongated |
Elongated |
Norm |
Elongated |
|
Fibrinogen |
1,5-3,0 g / l |
Norm |
Norm |
Norm |
Decreased |
|
Products |
0-7 mg / ml |
Norm |
Norm |
Norm |
Enhanced |
Treatment of hemorrhagic disease of newborns
To treat hemorrhagic disease of the newborn, vitamin K3 (vikasol) is used. Intramuscular injection of 1% solution was calculated from the calculation of 0.1-0.15 ml / kg once daily for 2-3 days.
With severe bleeding, life-threatening hemorrhages, freshly frozen plasma 10-15 ml / kg or a concentrated preparation of the prothrombin complex (PP5B) 15-30 U / kg intravenously bolus is injected simultaneously.
With the development of hypovolemic shock, infusion therapy is first performed (after a freshly frozen plasma is transfused at a dose of 20 ml / kg) and, if necessary, the erythrocyte mass is transfused from the calculation of 5-10 ml / kg.
How is hemorrhagic disease prevented in newborns?
Prevention is not performed by all newborns, but only from a high-risk group. These include prematurity, especially premature infants; children deprived of breast-feeding, on parenteral nutrition, receiving antibiotics. In addition, children who have suffered severe perinatal hypoxia and asphyxia, birth trauma, children after cesarean section, children from pregnancy with gestosis on the background of low synthesis of estrogens, and children from pregnancy with the phenomena of hepatopathy, enteropathy, dysbiosis and dysbiosis of the intestine in the mother .
Risk factors also include taking the latest medicines for mothers of a number of drugs (anticonvulsants, anticoagulants of indirect action, broad-spectrum antibiotics and anti-tuberculosis drugs).
For the purpose of prophylaxis, 1% solution of vikasol is prescribed at the rate of 0.1 ml / kg intramuscularly once for 1-3 days.
In the United States, on the recommendation of the American Academy of Pediatrics, since 1960, vitamin K (phytomenadione) (1 mg) is administered intramuscularly to all newborn children.