Excessive intake of vitamin A
Introduction
Introduction to excessive intake of vitamin A Excessive intake of vitamin A can cause hypervitaminosis A, divided into acute and chronic. Excessive vitamin A will reduce the stability of cell membrane and lysosomal membrane, leading to damage of cell membrane, release of tissue enzymes, causing lesions of various organs such as skin, bone, brain and liver. Brain damage can increase intracranial pressure; bone tissue degeneration causes bone resorption, deformation, new subperiosteal formation, blood calcium and urinary calcium. Damage to liver tissue causes enlargement of the liver and changes in liver function. basic knowledge The proportion of illness: 0.0025% Susceptible people: children Mode of infection: non-infectious Complications: Asperger Syndrome Pertussis Intestinal Piriformis Disease Asthma-like Bronchitis Kawasaki Disease Hemorrhagic Shock and Encephalopathy Syndrome Large Amniotic Fluid Inhalation Fifth Day Syndrome Multiple Tic Syndrome Thalassemia Aortic Catheter Artery Children with ADHD children with tic disorder children with pancreatic insufficiency and neutropenic syndrome children learning disabilities children stuttering children sleep disorders children with fecal disease children enuresis children abdominal pain children autism children acute benign myositis childhood mood disorders children's spirit Schizophrenia anal atresia anal membrane atresia expired
Cause
Excessive intake of vitamin A
The prepared cod liver oil preparation has two types of concentrated cod liver oil drops and pills, and the components thereof are vitamin D and vitamin A. These two vitamins are important for children in their growth and development. Vitamin D is mainly used to prevent rickets, and vitamin A plays an important role in ensuring the development and function of children's eyes, skin and other organs.
But one problem is often overlooked, that is, in these cod liver oil preparations, the content of vitamin A is much higher than the content of vitamin D. If you use this type of preparation for children for a long time, or use a larger dose to treat rickets, it is easy to cause a large amount of vitamin A to accumulate in the body and produce toxicity.
Children should be cautious of vitamin A poisoning. A large intake of vitamin A pure preparations can cause acute poisoning. It has been reported that 300,000 IU of vitamin A can cause symptoms of poisoning within a few days; if excessive intake of vitamin A is taken for a long time, chronic poisoning can occur, taking 25,000 to 50,000 IU daily for 3 months to cause chronic poisoning. . The polar bear liver contains the largest amount of vitamin A, which can cause vitamin A poisoning after eating. It has been reported that adults who have eaten a complete dog liver within 1--2 days cause acute vitamin A poisoning. Children consume some chicken liver daily for several months causing chronic poisoning of vitamin A. In addition, it has been suggested that poisoning is related to body specificity, that is, vitamin A absorption, utilization, excretion, and intrahepatic storage, and there are individual differences.
Because parents lack the knowledge of rational application of vitamin A, long-term or short-term large doses of excessive cod liver oil for children, and medical staff are also lack of vigilance. Due to individual differences and the amount of vitamin A stored in the liver, the dose of vitamin A poisoning can vary greatly. It has been reported that an adult dose of more than 500,000 to 1 million IU, and a child dose of more than 300,000 IU can cause disease. Some children also take 10,000 to 20,000 IU a day, and symptoms can appear for several months.
Prevention
Excessive intake of vitamin A
Promote universal knowledge of nutrition and hygiene, correct parents' abuse of vitamin A preparations and bad eating habits. For example, animal liver is an organ that stores vitamin A. It is rich in nutrients, but it is not suitable for eating every day. Food should be varied. Prevent the occurrence of iatrogenic vitamin A poisoning.
The daily physiological requirement of vitamin A is 2000 IU. Do not exceed the required amount when applying concentrated cod liver oil or vitamin A preparation; when large doses must be used, the medication time should be strictly limited. Immediately after the occurrence of poisoning, the supply of vitamin A and carotene should be stopped, because carotene can be decomposed into vitamin A in the body. The acute symptoms of vitamin A poisoning after drug withdrawal usually disappear within 72 hours to 1 week, and other performances are also reduced and improved. The X-ray signs of the skull recovered within 6 weeks to 2 months; the long-line X-ray signs recovered slowly, often taking about half a year, and the serum vitamin A level can reach several months. Vitamin K can be used in patients with bleeding.
Giving your child reasonable use of cod liver oil is the only measure to prevent poisoning. These include:
1. Strictly follow the doctor's advice to take the cod liver oil preparation for the child. It should not be abused and should not be used. Generally, infants under 1 year old can give 3-4 drops of concentrated cod liver oil per day, which should not exceed 6 drops.
2, prevention and treatment of infantile rickets, try to give children a pure vitamin mouth preparation without vitamin A.
3. If it is necessary to supplement the child with a large dose of vitamin A due to special circumstances, the doctor should strictly limit the time of administration.
4. When the child takes cod liver oil, once it is found to have suspicious symptoms of vitamin A poisoning, stop taking it immediately and take the child to the hospital for treatment.
Beijing applied vitamin AD to strengthen fresh milk to feed children (including vitamin A 2000IU / L), observed to effectively prevent vitamin A deficiency, and did not see the symptoms of excessive vitamin A.
Medical staff should understand and master the dose of vitamin A preparation, and teach parents to not abuse the vitamin A preparation, change the cod liver oil as a tonic, the dose is larger, and the long-term taking time is harmless. Do not eat large amounts of animal liver in the diet. If vitamin D is needed for the treatment of a building disease, a pure vitamin D preparation should be used.
Complication
Excessive complications of vitamin A intake Complications Asperger Syndrome Pertussis Intestinal Piriformis Disease Asthmatic Bronchitis Kawasaki Disease Hemorrhagic Shock and Encephalopathy Syndrome Large Amniotic Fluid Inhalation Fifth Day Syndrome Multiple Tic Syndrome Thalassemia Artery Catheter Artery Thrush ADHD children with tic disorder children with pancreatic insufficiency and neutropenic syndrome children learning disabilities children stuttering children sleep disorders children with fecal disease children enuresis children abdominal pain children autism children acute benign myositis childhood disorders children schizophrenia Anal atresia, anal occlusion, expired birth
There are many complications of vitamin A poisoning, especially children are more susceptible to complications. There are mainly the following:
Asperger syndrome, whooping cough, intestinal prairie, asthmatic bronchitis, Kawasaki disease, hemorrhagic shock, encephalopathy syndrome, large amniotic fluid inhalation, fifth day syndrome, multiple tic syndrome, thalassemia , patent ductus arteriosus, thrush, pediatric hyperactivity disorder, child tic disorder, childhood pancreatic insufficiency, neutropenia syndrome, children's learning disabilities, children's stuttering, children's sleep disorders, children's feces, children's enuresis Abdominal pain in children, autism in children, acute benign myositis in children, mood disorders in children, schizophrenia in children, anal atresia, anal insufficiency, expired birth.
Symptom
Excessive symptoms of vitamin A intake Common symptoms headache and vomiting increased intracranial pressure, drowsiness, redness and swelling of the back of the hand
Clinical manifestations appear 6 to 8 hours after ingestion, up to 1 to 2 days. Mainly have symptoms of lethargy or excessive excitement, headache, vomiting and other high intracranial pressure. After 12-20 hours, skin redness and swelling appear. After peeling, the thick parts of the palm and sole are most obvious, and the back is normal after several weeks. Infants and young children with high intracranial pressure as the main clinical features, the frontal bulge can occur in patients with patents of the posterior fornix. The cerebrospinal fluid examination pressure is increased, the number of cells is normal, the protein amount is low, and the sugar is normal. Plasma vitamin A levels have increased dramatically, reaching more than 500ug/L (normal adult 100-300ug/L).
Examine
Excessive intake of vitamin A
1. X-ray examination has special value for the diagnosis of this disease. It is characterized by abnormal shape of tubular bone, bone absorption, fracture; change of tarsal plate and soft tissue swelling; formation of new bone under the periosteum in the backbone; widening of cranial suture, full expansion of anterior .
2, cerebrospinal fluid pressure increased, up to 2.55kPa (260mmH2O), cells and sugar in the normal range, it was found that protein decreased or normal low value.
3, check serum vitamin A, often up to 1,000 ~ 6000g / L or more.
Diagnosis
Diagnosis and identification of excessive intake of vitamin A
Diagnostic criteria for hypervitamin A:
1. A single application of vitamin A over 300,000 international units can cause acute poisoning. Long-term (weeks or months) overdose of vitamin A can cause chronic poisoning.
2. The symptoms of acute poisoning include nausea, vomiting, lethargy, anterior sacral bulging, diplopia and cranial nerve spasm. Symptoms of chronic poisoning include irritability, loss of appetite, itching, weight loss, cleft palate, long bone pain, hepatosplenomegaly, scaling of the hands and feet, softening of the skull and increased intracranial pressure.
3. X-ray long bone plain film: thickening of the middle segment of the cortex.
4. Serum vitamin A content increased (> 3.5 mol / l, 100 g / dl).
Differential diagnosis
The clinical manifestations of vitamin A poisoning can be divided into acute poisoning (disposable injection of more than 300,000 IU) and chronic poisoning (infant infants and young children intake of 50,000 to 100,000 IU, more than 6 months, can appear poisoning). Acute poisoning diagnosis is not difficult, chronic poisoning is easy to be misdiagnosed. Its main performance is:
1, the general symptoms: irritability, irritability, sharp loss of appetite, low fever, weight loss, poor spirit.
2, skin symptoms: itching, scaling, hair sweat, easy to fall off, cleft lip and palate.
3, skeletal symptoms: limb pain, soft tissue swelling, prominent crotch on both sides.
4, X-ray features: tubular bone changes, new bone formation under the periosteum, periosteal hyperplasia, severe osteophyte embedding deformity, so that the epiphysis and backbone closure prematurely, the head changes, cranial suture widening, the former blood stasis expanded.
In order not to be misdiagnosed or misdiagnosed, clinicians should be alert to the above-mentioned symptoms and bone X-ray findings, should closely observe and inquire about the history of vitamin A. In particular, it should be corrected that the cod liver oil is a misunderstanding of nutrition medicine, the more the better, in the treatment of rickets, the use of pure vitamin D preparation should be promoted. Due to the improper proportion of vitamin A and D in many cod liver oils (there are 50 IU of vitamin A, D5000 IU or 10,000 IU of vitamin A, D 5000 IU, etc.), vitamin A is high, vitamin D is not enough to treat rickets, and vitamins are often caused when the dose is increased. A poisoning. Once the diagnosis is confirmed, the drug should be stopped immediately and the intake of carrots and vegetarians should be reduced. Vitamin E 150 mg/d can be used 3 times a day to promote vitamin A excretion. Generally, the clinical symptoms gradually disappear within 1 to 2 weeks, but the plasma vitamin A concentration is restored. It often takes several months.
