Vitamin B2 deficiency in children
Introduction
Brief introduction of vitamin B2 deficiency in children Due to insufficient supply of riboflavin in the diet, or due to some secondary causes, such as increased urgency, absorption, and utilization of riboflavin deficiency, skin mucosal lesions such as tongue, lip, mouth and external genitalia are known as nuclear yellow. Sustained disease. Riboflavin, vitamin B2, is named because it is yellow in color and contains ribitol in its molecule. basic knowledge The proportion of illness: 0.006% Susceptible people: children Mode of infection: non-infectious Complications: anemia, iritis
Cause
Pediatric vitamin B2 deficiency disease etiology
Insufficient intake, malabsorption (35%):
Riboflavin deficiency is more common in long-term consumption of a large number of starchy meals, but also eat less animal protein and fresh vegetables. Absorption disorders: malnutrition, chronic gastrointestinal disorders, biliary stricture, hepatitis, etc. can affect riboflavin absorption.
Iatrogenic riboflavin deficiency (23%):
Found in neonatal hyperbilirubinemia when phototherapy, because bilirubin and riboflavin can be simultaneously degraded, riboflavin in plasma decreased significantly. After long-term phototherapy of neonates, especially those who are breast-fed, it is easy to cause riboflavin deficiency, because the riboflavin content in breast milk is only 1/5 of that of milk. Renal failure can lose water-soluble vitamins during hemodialysis. Long-term intravenous nutrition therapy and the loss of riboflavin are likely to lead to riboflavin deficiency.
Increase in demand (17%):
Such as burns, trauma, tuberculosis or long-term fever. Increased protein consumption in the body increases the amount of riboflavin required, and is also prone to riboflavin deficiency.
Pathogenesis
Riboflavin is a constituent of two kinds of coenzymes, flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN), which are widely distributed in all tissues and participate in various redox reactions. The reaction includes direct oxidative phosphorylation in the tricarboxylic acid cycle and metabolism of fatty acids and oxidation. Riboflavin deficiency not only affects glucose metabolism, but also affects fat metabolism, alters the concentration of phospholipids in plasma and tissues, and blocks the ingestion of vitamin B2 and folic acid into their coenzyme derivatives. If the body's core flavin is insufficient, it will lead to disturbance of substance metabolism. Recent studies have shown that riboflavin is closely related to the antioxidant defense system in the body, and it is also beneficial for reducing swelling, preventing and treating tumors, and reducing cardiovascular and cerebrovascular diseases. When riboflavin is deficient, the pigment layer in the epidermis of the body and the pigment in the body of the body are reduced or disappeared. In severe cases, the keratinized metamorphosis and the capillaries of the surface layer are dilated. The slices of the lips and tongue also showed significant keratinization. The follicular keratinization at the junction of the nose and lips is significant. The gingival margin is inflamed, the conjunctiva can be slightly hyperemia, and riboflavin coenzyme is also necessary for the reduction of methemoglobin into hemoglobin. Therefore, erythropoietin may be increased in red blood cells when riboflavin is deficient.
Prevention
Prevention of vitamin B2 deficiency in children
No special precautions, pay attention to the diet structure of children, and encourage the intake of riboflavin-rich foods such as liver, eggs, pork and milk.
Complication
Pediatric vitamin B2 deficiency complications Complications anemia iritis
1. Eye: corneal ulcer or corneal opacity, iritis. Iris, eye disease, that is, inflammation of the iris. Sometimes the ciliary body behind the iris will also be inflamed together. When the iris is inflamed, the tiny white cells in the inflamed area and the excessive protein leaking from the small blood vessels in the eye float in the aqueous humor between the iris and the cornea.
2. Anemia: bone marrow dysplasia anemia. .
Symptom
Symptoms of vitamin B2 deficiency in children, common symptoms, tears, mouth, sores, photophobia, loss of vascular hyperplasia, keratitis, blood stasis, tongue inflammation, corneal opacity
Riboflavin deficiency is mainly manifested in changes in the lips, tongue, eyes and skin.
1. Lip and tongue symptoms are more common in older children.
(1) angular cheilitis (also known as angular cheilitis): also known as mouth sore, the beginning of the mouth is wet, white, erosive, and gradually cracks. The crack extends from the mouth to the outside by a length of 1 to 2 cm, which is found on one side or on both sides, but is heavier on one side. The fissure of the fissure is exfoliated, forming an ulcer, often with yellow or yellowish black crusting, and bleeding easily when opening the mouth. Older children with angular sore are prone to chronicity, and dark brown pigmentation is common at the junction with the skin.
(2) cheilitis: all mucous membranes of the upper and lower lips can be brightly reddish, and the longitudinal cracks of the lips increase. Sometimes, when the mouth is big or crying, the cracks and bleeding. Sporadic blood stasis can be seen along the junction of the mucous membrane and the skin. This lesion is heavier in the lower lip and has a narrow scar every time after recovery.
(3) glossitis: the tongue is smooth, bright magenta, peeping under intense sunlight, and can be microscopic blue in red. In the case of glossitis, the nipple nipple and the posterior nipple of the tongue are thick in the early stage, and then shrink, disappear, and the nipple is flattened. The middle part of the tongue is red with atrophy and fissure. Pain and loss of taste.
2. Eye symptoms are not as common as lip and tongue symptoms. Generally, vascular proliferative conjunctivitis, which is characterized by inflammation and hyperplasia of capillaries, invades the cornea by the conjunctiva. Therefore, in 1 to 2 days, many capillaries are formed at the edge of the conjunctiva to form ring keratitis. One or two small white blisters may also appear on the edge of the cornea. There is photophobia, tearing, burning or itching. The disease progresses further, and the proliferating capillaries can invade all of the cornea, causing ulceration of the corneal opacity and causing iritis. The gingival margin is also inflamed, and the following sputum and eyelids are heavy. Common redness and sticky secretions.
3. The skin symptoms are mainly seborrheic dermatitis, which occurs mostly at the junction of the nose and the lips, and there are many sebaceous glands such as the nose, the back of the ear and the frontal eyebrow. At the beginning, the sebum overflows, which is filiform sebum, which is stuffed in the sebaceous gland. It is high in the skin surface, and more often forms a dry sputum. Yellow-white desquamation can be seen. After the wiping, red spots can be seen in the skin pleats. Some skin symptoms show scrotal dermatitis or labia inflammation.
4. Anemia can be seen in positive cells and anemia of the pigment with bone marrow dysplasia.
Examine
Pediatric vitamin B2 deficiency check
1. Determination of blood and urine riboflavin concentration Determination of blood nuclear yellow content and 24h urinary excretion of riboflavin, normal human blood contains riboflavin 50g, urinary excretion within 0.5h is 0.5 ~ 1.0mg, blood level in riboflavin deficiency And the amount of urinary excretion is reduced. However, direct blood test and urinary riboflavin concentration or discharge can not truly reflect the lack of flavin in the body.
2. Determination of vitamin B2 in cells The content of vitamin B2 in cells is a good indicator for assessing the nutritional level of vitamin B2. The content is less than 140g/L, and >200g/L is good.
3. Load test After oral administration of 5 mg of vitamin B2, the amount of vitamin B2 discharged in 4 hours of urine was less than 350 g.
4. Urinary creatinine nucleoside flavonoids can be associated with clinical signs of riboflavin deficiency when gram of creatinine core flavin <30 g is removed.
5. Vitamin B2 creatinine ratio Vitamin B2 creatinine ratio <27 g / g is insufficient, 27 ~ 79 g / g is low, 80 ~ 269 g / g is appropriate, > 270 g / g is sufficient.
6. Red blood cell glutathione reductase (EGR) erythrocyte glutathione reductase (EGR) activity (Activation coefficient, AC) determination, AC is currently recognized as a specific method for the detection of flavin flavin. This coefficient represents the degree of saturation of red blood cells to FAD. The normal AC value is 0.2-1.2. The AC value increases after the addition of FAD during the test. The erythrocyte glutathione reductase activity caused by riboflavin is enhanced, which is an early sign of riboflavin deficiency. AC>1.2 indicates the vitamin B2 in the tissue. insufficient. This method does not apply to patients with G-6PD because the amount of red blood cells required for FAD is significantly increased.
Bone marrow examination can detect red blood marrow hypoplasia and thus cause aplastic anemia.
Diagnosis
Diagnosis and identification of vitamin B2 deficiency in children
diagnosis
1. History and clinical features Clinical diagnosis depends on the special symptoms of the disease, detailed dietary history and rapid response to riboflavin treatment.
2. Laboratory tests can help early diagnosis, early detection of subclinical biochemical changes, early prevention.
Differential diagnosis
1. Niacin deficiency is distinguished from dermatitis caused by niacin deficiency. The skin symptoms of riboflavin deficiency are different from those of niacin deficiency. The lack of riboflavin is a filiform sebum overflowing from the junction of the nose and the lip. And niacin deficiency dermatitis, more common in exposed or easily rubbed parts.
2. Vitamin B6 deficiency lip dry cracking attention and vitamin B6 deficiency identification, laboratory tests to exclude other causes and therapeutic tests are necessary.
