neonatal hemorrhage
Introduction
Introduction Neonatal hemorrhagic disease, the neonatal vitamin K deficiency hemorrhagic disease, is a common bleeding disorder in newborns. It is also known as neonatal natural hemorrhage, which is caused by vitamin K deficiency in the body, resulting in a vitamin K-dependent coagulation factor including hemorrhagic diseases caused by low activity of II, VII, IX, and X. Neonates that occur within 1 week are called neonatal hemorrhagic disease. The main feature is that the child suddenly has bleeding, and other conditions are normal, there is no serious underlying disease, platelet count and fibrinogen are normal, there is no fibrin degradation product in the blood, bleeding within a few hours after the injection of vitamin K1 can be very Stop quickly.
Cause
Cause
(1) Causes of the disease
The disease is due to vitamin K deficiency. The reasons for vitamin K deficiency are:
1. Low vitamin K storage
Due to the poor permeability of vitamin K through the placenta, the pregnant mother vitamin K rarely enters the fetus. Only 10% of the pregnant mother's vitamin K can reach the fetus through the placenta. The fetal vitamin K is stored in a small amount, so the blood vitamin K is born at the time of birth. The level is generally low and the vitamin K storage in the liver is also low. Low-born birth weight infants such as premature infants and small for gestational age have lower levels of vitamin K in their blood.
Insufficient intake
The content of vitamin K in breast milk (15g/L) is only 1/4 of that of milk (60g/L). At the same time, the intestinal flora of breast-fed infants produces less vitamin K, and the amount of newborn breast milk is insufficient. Therefore, breast milk The incidence of feeders is 15 to 20 times higher than that of milk-fed. Mother's diet lacks vitamin K, such as green vegetables, beans, liver and eggs, and even vitamin K deficiency.
3. insufficient synthesis
Vitamin K is mainly synthesized by normal intestinal flora, and the intestinal flora of newborn newborns has not yet been established, affecting the synthesis of vitamin K. Intestinal inflammation or oral antibiotics can inhibit the normal intestinal flora, resulting in insufficient vitamin K synthesis.
4. Other
Children with hepatobiliary disorders, congenital biliary atresia, etc., due to reduced bile secretion, can affect the absorption of vitamin K, aggravation of vitamin K deficiency. Certain factors can cause bleeding in neonates with vitamin K deficiency, such as prenatal use of certain drugs, such as anticonvulsants, anticoagulants (dual coumarin), rifampicin, isoniazid, etc., pregnancy or childbirth. The process of comorbidities, etc., can aggravate vitamin K deficiency.
(two) pathogenesis
Vitamin K deficiency causes bleeding because the coagulation biological activity of certain coagulation factors is directly dependent on the presence of vitamin K. The glutamic acid residues of coagulation factors II, XII, IX, and X need to undergo carboxylation, and their glutamic acid residues need to be carboxylated into -carboxyglutamic acid, which has more Ca2 binding sites and increases calcium. The binding site has the biological activity of coagulation. This carboxylation process requires the involvement of a vitamin K-dependent carboxylase, so these four coagulation factors are also known as vitamin K-dependent factors. If vitamin K deficiency occurs, the four coagulation factors are inactive. The above four coagulation factors are only non-functional proteins, which cannot participate in the coagulation process, and cause coagulation dysfunction, leading to bleeding.
Examine
an examination
Related inspection
Bleeding time hemoglobin vitamin K
The main tests to be performed include coagulation function tests, including prothrombin time (PT), activated partial thromboplastin time (APTT), kaolin partial thromboplastin time (KPTT), thrombin time (TT), etc. Fibrinogen and platelets were measured. If vitamin K deficiency is present, the activity of vitamin K-dependent factors (II, VII, IX, and X factors) decreases, and PT, APTT, and KPTT are prolonged, but TT, fibrinogen, and platelet counts are normal. In addition, hospitals with conditions can also confirm the diagnosis by measuring vitamin K deficiency-inducing protein and vitamin K levels.
Diagnosis
Differential diagnosis
It should be differentiated from the bleeding caused by other causes within 1 week after birth.
1. Gastrointestinal bleeding: It should be differentiated from gastrointestinal bleeding caused by swallowing syndrome, stress ulcer, gastrointestinal malformation and infection. These children have no coagulopathy. The swallowing syndrome is the blood of the mother's birth canal when the newborn is born or the amniotic fluid with blood. The vomiting occurs soon after birth. The vomit is brown or bloody, but the blood volume is small. Stop vomiting. In addition, the alkali denaturing test (Apt test) helps to identify maternal blood and blood.
2. Painful bleeding: It occurs mostly in the exposed part of childbirth and appears after birth. However, it should be noted that the birth injury can coexist with the disease at the same time, making the bleeding worse.
3. Others: If the umbilical hemorrhage should be associated with the umbilical cord is not tight, umbilical infection or granuloma caused by bleeding. Vaginal bleeding should be differentiated from "false menstruation." Hereditary telangiectasia can cause gastrointestinal bleeding in the early stages of neonatal development.
