infantile tetany
Introduction
Introduction to infant hand, foot and ankle Vitamin D deficiency hand and foot rickets, also known as infantile hand and foot snoring, the vast majority found in infancy, mainly due to vitamin D deficiency, resulting in low serum calcium, increased neuromuscular excitability, convulsions and hand, foot and other symptoms. In recent years, the incidence has been decreasing year by year. The cause of the disease is the same as that of rickets, but the clinical manifestations and blood biochemical changes are different. Although the disease is often accompanied by mild rickets, the bone changes are not serious, the blood calcium is low and the blood phosphorus is normal, and the alkaline phosphatase is increased. Serum calcium ion reduction is the direct cause of this disease. Under normal circumstances, serum calcium is about 60% of total calcium. If serum total calcium is reduced to 1.75~1.88mmol/L (7-7.5mgdl), or When the calcium ion drops below 1mmol/L (4mg/dl), the symptoms of convulsion can occur. In the case of hypocalcemia, the parathyroid glands are stimulated to show secondary hyperfunction and secrete more parathyroid hormone. In order to increase the excretion of phosphorus in the urine, and to decalcify the bones and supplement the deficiency of blood calcium, blood calcium cannot maintain normal levels when the parathyroid gland is not fully compensated. basic knowledge Sickness ratio: 0.0004% Susceptible people: children Mode of infection: non-infectious Complications: muscle spasm
Cause
The cause of infantile hand and foot spasm
The cause of the disease is the same as that of rickets, but the clinical manifestations and blood biochemical changes are different. Although the disease is often accompanied by mild rickets, the bone changes are not serious, the blood calcium is low and the blood phosphorus is normal, and the alkaline phosphatase is increased.
Serum calcium ion reduction is the direct cause of this disease. Under normal circumstances, serum calcium is about 60% of total calcium. If serum total calcium is reduced to 1.75~1.88mmol/L (7-7.5mgdl), or When the calcium ion drops below 1mmol/L (4mg/dl), the symptoms of convulsion can occur. In the case of hypocalcemia, the parathyroid glands are stimulated to show secondary hyperfunction and secrete more parathyroid hormone. In order to increase the excretion of phosphorus in the urine, and to decalcify the bones and supplement the deficiency of blood calcium, blood calcium cannot maintain normal levels when the parathyroid gland is not fully compensated.
Normal serum calcium is divided into diffusible calcium (diffusidblecalcium, which accounts for about 60% of total calcium) and non-dispersed calcium. The latter is part of protein binding (about 40%). Most of the non-dispersed calcium binds to albumin. Partially bound to globulin, when the serum H+ concentration is increased, the calcium bound to the protein is reduced, about 80% of the dispersible calcium is ionized (ie Ca++), and the rest is with phosphate, bicarbonate or phlegm. The main factors affecting serum calcium ion (Ca++) concentration are acid ion concentration, phosphate ion concentration and protein concentration. According to the formula of [Ca++][HCO-3][HPO=4]/[H+] =k, The higher the concentration of hydrogen ions in the blood, the more calcium ions. In the case of alkali poisoning, the opposite is true. The more phosphate, the less calcium ions. The higher the plasma protein, the less calcium can be dispersed and the calcium ions are correspondingly reduced. When the protein is low, the calcium ion is relatively high. Therefore, when the plasma albumin of the child with nephrotic syndrome is significantly decreased, the bound calcium is also reduced, even if the total serum calcium is below the level of general hand, foot and sputum, but the ion Calcium value is not low, In spasticity does not occur, in the clinical work, direct determination of serum calcium concentration is more difficult, but using the graph (FIG. 14-21) is obtained as shown in serum total amount of calcium ions from the plasma calcium and total protein.
The factors that promote the reduction of blood calcium are 1 season: the highest incidence rate in spring, the highest incidence in March-May in Beijing, because infants rarely touch direct sunlight after winter, vitamin D deficiency has reached the peak at this time. In the spring, it began to contact with sunlight. The vitamin D in the body increased sharply, the blood phosphorus increased, the calcium-phosphorus product reached 40, a large amount of calcium was deposited on the bone, and the blood calcium temporarily decreased to promote the onset. 2 age: the age of onset was less than 6 months, Beijing Children Among the 1,297 cases seen in hospitals from 1950 to 1955, 41.3% were under 3 months, 25.0% were 4-6 months, 20.4% were 7-12 months, 10.7% were 1 to 3 years old, 3~ 14 years old 2.6%, within 6 months, the baby grows fastest and needs more calcium. If the supply is insufficient in the diet, vitamin D deficiency is easy to occur. The early age of onset is related to the lack of vitamin D in the mother's pregnancy. Vitamin D stored in infants is sufficient for 3 months, 3 immature and artificial feeding are easy to develop, 4 long-term diarrhea or obstructive jaundice can reduce the absorption of vitamin D and calcium, resulting in lower blood calcium.
Long-term diarrhea or obstructive jaundice.
Prevention
Baby hand, foot and ring disease prevention
The method of preventing hand and foot snoring is the same as the prevention of rickets. It should be treated promptly for infantile diarrhea to prevent electrolyte imbalance. When the baby suffers from various viral hepatitis, the liver cells are damaged, resulting in the formation of 25 hydroxy D. Concurrent with hypocalcemia, vitamin D2 or D3 should be added as soon as possible.
1 Popular precautions
(1) Strengthen the publicity work, including the prevention of rickets in pregnant women, perinatal period and breast-feeding period, and implement them in the work of maternal and child health management system.
(2) Promotion of legal VitD fortified foods In recent years, the Nutrition Research Laboratory of Beijing Pediatric Research Institute has developed vitamin AD fortified milk (AD milk), including VitA2000IU/L, VitD600IU/L. It has been proved by experiments that this kind of fortified milk no longer increases VitD preparation, which is solved. The lack of VitA VitD in milk feeding and the safest, most effective and convenient way to prevent it from overdose has been promoted in Beijing. It is worthy of introduction to local applications. (3) Strengthening the rational management of breast milk and feeding kidney breastfeeding for 8 months, and adding food supplements on time.
(4) Strengthen children's outdoor activities, group children to strengthen three-bath exercise (air bath, sunbathing, water bath).
(5) Prevention and early treatment of common diseases in infants and young children.
(6) The urban construction department should take into account the sun exposure angle in the design of the living room. The green activity area of children (including the elderly) should be considered in the building group, or the children's activity area should be established on the flat roof of the building, especially in the north.
(7) Artificial ultraviolet devices should be introduced into conditional support institutions.
2 drug prevention law
(1) Emphasis on outdoor activities during pregnancy is not only to prevent the sun's ultraviolet rays from preventing rickets, but also to the body more beneficial, especially in the third trimester of pregnancy, in addition to sunshine, daily supplementation of VitD400IU.
(2) Daily oral administration of VitD400IU after 1~2 weeks, or oral administration of VitD3~50,000 IU per day, or oral administration of VitD10~150,000 IU of breast milk and milk-fed infants 400-500ml per day. Generally, calcium is inferior to calcium in milk. It can be easily absorbed and utilized in summer and autumn. It can be used in summer and autumn. After entering the winter, it will take 10 to 150,000 IU of VitD orally. It will be re-injected once every two to three months (ie, the end of winter). It is especially suitable for rural use in this way. (3) Children with premature infants and children with digestive tract diseases may take a little bit of VitD prevention, but avoid excessive poisoning to avoid poisoning. China has a vast north and south area, different urban and rural conditions, and different conditions for children. In high-rise buildings, the degree of crowding of bungalows should be different according to local conditions.
Complication
Complications of infantile foot and ankle Complications
Can cause throat sputum, throat snoring, difficulty breathing and purpura.
Symptom
Infant hand, foot and ankle symptoms Common symptoms Difficulty breathing Asphyxia, convulsions, sudden convulsions during sleep, difficulty in inhalation, slanting fingers
Diagnosis of hand, foot and sputum, in addition to attention to medical records related to age, season, premature birth and other factors, should be based on the following three aspects, 1 active symptoms: convulsions in infants is the most important, there are several consecutive convulsions without infectious diseases For the symptoms or signs, the first consideration is the disease. The larger children are the most common with hand, foot and sputum. The hand, foot and sputum are the special symptoms of the disease, that is, the diagnosis can be confirmed without other symptoms. 2 Signs: As mentioned in the above section, 3 Qualitative examination of urinary calcium, mostly negative, this method is simple and easy to use, it is worthwhile to use, 4 if necessary, serum calcium can be tested, mostly down to 1.88mmol / L (7.5mg / dl), or even down to 1 ~ 1.25mmol / L ( 4 ~ 5mg / dl), while serum alkaline phosphatase increased, as serum inorganic phosphorus, or low or normal, or even higher than 2.26mmol / L (7mg / dl) (more common in premature infants), this is Different from rickets, blood phosphorus is generally reduced in patients with rickets. At present, serum free calcium can be quickly and accurately measured with new instruments, and should be applied clinically.
1, dominant symptoms
(1) Convulsion: It is the most common dominant symptom in infants. It is characterized by no fever in children, no other causes, and sudden seizures. Most patients have multiple seizures, repeated repeated episodes, daily episodes. The number of times ranges from 1 to 20 times, each time is from a few seconds to half an hour. When the time does not occur, the child's expression is almost normal. When the convulsions are mostly sensational loss, the rhythm of the hand and foot twitches, the facial muscles also squat, the eyeball Upturned, incontinence, all morbidity and other diseases of convulsions, young babies sometimes only see facial muscles twitching is the initial symptoms of the disease, as the sputum part, more common in the left and right sides, even or biased on one side.
(2) Hand and foot sputum: The special symptoms of the disease of the hand and foot sputum, the wrist is bent, the fingers are straight, the thumb is close to the palm, the toes are straight and the ankle is slightly curved, arched, often seen in larger infants and In children, infants within 6 months rarely develop this symptom.
(3) Throat: mainly seen in infants and young children before the age of 2, the throat makes breathing difficult, the inhalation is prolonged and croup, which can cause sudden death due to asphyxia. It should be mentioned that intramuscular injection for severe children with hand, foot and ankle Occasionally, the throat can be induced.
(4) Other symptoms: There are often nervous disturbances such as sleep uneasiness, easy to cry, sweating, etc., fever is not the symptoms of the disease itself, due to other first-coming or concurrent diseases.
2, hidden symptoms
Common signs such as the following, only signs and without the above symptoms, can be called recessive hand and foot sputum.
(1) Face-faced nerve test (Foster's sign, Chvostek's sign): use the fingertip or a small hammer to strike the seventh brain nerve through the ear, which can make the facial muscle contract, mainly the contraction of the upper lip or eyelid. 2 Pre-year-old children can get positive results, except for newborns, because normal newborns are common in the first few days or even one month, when there is no calcium deficiency. Children after 2 years old are occasionally seen in other For neurological diseases, various symptoms and signs disappear gradually after appropriate treatment, and only the facial muscle reaction remains for a long time.
(2) reflex: use a small hammer to slam the phrenic nerve on the outside of the knee (above the humeral head), and the foot contracts to the outside when positive.
(3) Artificial hand sign (Trouss-eau'ssign): Wrap the upper arm with the cuff of the sphygmomanometer, and pump up to pause the pulse on the temporal side. If it is positive, see the handcuff within 5 minutes. .
3, the course of disease
If early diagnosis and treatment can be performed, most cases can stop convulsions within 1-2 days, but severe throat can cause sudden death due to difficulty in inhalation. Severe convulsions are also dangerous. If there is serious infection or diarrhea in infants, Can make this disease worse or prolonged.
Examine
Baby hand, foot and ankle examination
Laboratory inspection
Blood calcium is often lower than 1.7 ~ 1.9mmo1/L, if necessary, check free calcium, experimental treatment of calcium is also helpful for diagnosis.
Physical examination
(1) Face-faced nerve test (Foster's sign, Chvostek's sign): use the fingertip or a small hammer to strike the seventh brain nerve through the ear, which can make the facial muscle contract, mainly the contraction of the upper lip or eyelid. 2 Pre-year-old children can get positive results, except for newborns, because normal newborns are common in the first few days or even one month, when there is no calcium deficiency. Children after 2 years old are occasionally seen in other For neurological diseases, various symptoms and signs disappear gradually after appropriate treatment, and only the facial muscle reaction remains for a long time.
(2) reflex: use a small hammer to slam the phrenic nerve on the outside of the knee (above the humeral head), and the foot contracts to the outside when positive.
(3) Artificial hand sign (Trouss-eau'ssign): Wrap the upper arm with the cuff of the sphygmomanometer, and pump up to pause the pulse on the temporal side. If it is positive, see the handcuff within 5 minutes. .
Diagnosis
Diagnosis and diagnosis of infantile hand and foot sputum
diagnosis
Diagnosis can be performed based on clinical manifestations and examinations.
Differential diagnosis
Most of them belong to two situations.
The first category is the differential diagnosis of convulsions. For details, please refer to the convulsion chapter. In the neonatal period, special attention should be paid to productive injury, congenital brain hypoplasia and sepsis. If it is a larger baby, special attention must be paid to each Brain diseases in the onset of acute diseases (such as pneumonia, upper respiratory tract infection), encephalitis, meningitis with low fever (such as tuberculous meningitis, occasional lack of hyperthermia in meningococcal meningitis), infantile spasms, Hypoglycemia and lead poisoning have to be differentiated from epilepsy and hypoparathyroidism in childhood.
The second type is the differential diagnosis of laryngeal obstruction (see the section on laryngeal obstruction in respiratory diseases). The throat of hand, foot and ankle is mainly characterized by inspiratory croup. If there is no convulsion at the same time, Foster can be used. The levy is used to help diagnose.
In terms of etiology, infantile hand, foot and sputum is mainly due to the deficiency of vitamin D, resulting in low blood calcium, as well as other causes of hand and foot snoring, such as low magnesium and alkali toxic hand, foot and sputum, etc., in clinical manifestations It is the same as infantile hand, foot and ankle. Therefore, it is necessary to identify the different causes of hand, foot and ankle. For each case of hand, foot and ankle, clinically relevant problems should be carefully studied. The most important point is: There is a characteristic of vitamin D deficiency in hand, foot and ankle. Now, various types of hand, foot and ankle syndrome other than vitamin D deficiency hand, foot and ankle are outlined as follows. It should be noted that sometimes there may be several causes in one case. presence.
1. Hand, foot and ankle caused by parathyroid insufficiency. If the parathyroid gland is mistakenly cut during thyroid surgery, the parathyroid hormone may be deficient and the blood calcium may be lowered. The newborn may have temporary hypoparathyroidism. Phenomenon, because the mother's parathyroid function is strengthened during the fetal period, and the fetal parathyroid gland does not need to be active. This passive low-function phenomenon can last for several days after delivery. Some people think that the neonatal parathyroid function is Normal, but the human body's response to the regulation of the parathyroid gland is poor, so that blood calcium can not maintain normal levels. If the newborn is fed with milk, the calcium content in the milk is high, so calcium is not easily absorbed, and blood calcium is reduced. Hand, foot and ankle, in addition, there are primary or unexplained parathyroid dysfunction, the above three cases, have a common blood biochemical characteristics, that is, increased blood phosphorus, blood calcium, alkaline phosphatase, Should be treated with dihydrotachysterol or parathyroid hormone.
2, alkali-toxic hand, foot and sputum due to long-term vomiting or repeated gastric lavage caused by low-chlorine alkalosis, due to salicylic acid poisoning and other deep breathing, respiratory alkalosis, or due to improper infusion, intravenous drip of large amounts of carbonic acid Sodium hydrogen or the like can cause symptoms of calcium ion (Ca++) concentration to decrease.
3, low-magnesium hand and foot rickets with muscle twitching or convulsions as a symptom, relatively rare, easy to see in premature babies and small samples, mothers often have pregnancy poisoning, diabetes, hyperthyroidism, occasionally with citrate anticoagulation The blood transfusion of neonatal children with hemolytic disease, at this time the blood magnesium and calcium are reduced and there is a hand and foot sputum (normal serum magnesium value of 0.74 ~ 1.25mmol / L (1.48 ~ 2.5mEq / L)), also due to The diarrhea is prolonged for a long time, or the intestinal absorption is poor due to lack of enzymes, which affects the absorption of magnesium. There are also convulsions due to hyperaldosteronism or primary hypomagnesemia. The serum magnesium of the patient is reduced to 0.74mmol/L (1.48). Below mEq/L), facial muscle twitching, hand and foot movements, high blood pressure, tachycardia, etc., are not effective after calcium supplementation, but can be controlled after injection or oral administration of magnesium.
4, chronic kidney disease process relay of hand and foot sputum due to renal insufficiency, renal tubular phosphorus function reduction, increased blood phosphorus, resulting in lower blood calcium, such diseases are mostly albumin reduction or chronic acidosis, it is very Hand and foot spasm rarely occurs, but when serum calcium is extremely reduced, or the pH of the serum is increased by the input of an alkaline solution, symptoms of convulsions or hand and foot spasms may occur.
5, hyponatremia and hypernatremia treatment when dehydration such as insufficient sodium, or due to excessive intake of water, and hyponatremia, then occur, such as sleepiness, vomiting, convulsions and other neurological symptoms, such as infantile diarrhea In the process of dehydration and acidosis correction, although there is no alkalosis, blood calcium is not significantly reduced, but when blood sodium rises, blood potassium drops, hypernatremia occurs, symptoms of hand and foot spasm can occur, neonatal asphyxia Or respiratory distress syndrome, such as the input of a large amount of sodium bicarbonate solution, hypernatremia can occur and convulsions occur.
6, vitamin B6 deficiency and dependence in infants such as lack of vitamin B6 or vitamin B6 dependence, can also occur convulsions.
