gastroesophageal reflux in infants
Introduction
Introduction to infantile gastroesophageal reflux Gastroesophageal reflux (incertilegastroesophagealreflux, IGER) refers to the reverse flow of stomach and/or duodenum into the esophagus. GER is very common in children, and most of them are physiological phenomena. Stephen et al. classify pediatric GER into three types: 1 physiological reflux: more common in the retrograde flow of newborns and small babies after feeding. 2 functional reflux (or called vomiting): common in infants and young children, does not cause pathological damage. 3 pathological reflux: According to Carre's early statistics, accounting for about 1 in 500 of the newborn, reflux symptoms persist, often associated with aspiration pneumonia, asphyxia and growth and development disorders. basic knowledge The proportion of illness: 1% Susceptible people: children Mode of infection: non-infectious Complications: esophageal stricture aspiration pneumonia iron deficiency anemia
Cause
Causes of gastroesophageal reflux in infants and young children
(1) Causes of the disease
In the past, the cardiac sphincter was considered to be the only anatomical structure to prevent reflux of gastric contents. However, GER is not considered to be a single function of lower esophageal sphincter function, but is a combination of many factors, of which the lower esophageal sphincter is the primary. The anti-reflux barrier, normal peristalsis of the esophagus, mucosal flap of the esophagus, esophageal ligament, length of the esophagus of the abdomen, muscle clamping of the transverse ankle and His angle, also play a role in preventing reflux, if the above anatomy The structural generator is qualitatively or functionally diseased, and the contents of the stomach can be refluxed to the esophagus and cause esophagitis.
1. The first anti-reflux barrier - the lower esophageal sphincter in the early 1980s, most scholars believe that the lower esophageal sphincter does not actually exist in the anatomical structure, but only represents the name of a function, in recent years, with ultra-anatomical The deepening of the study suggests that this muscle structure does exist. The maturity of the fetal esophageal function occurs from the end of pregnancy to the first week after birth. The lower esophageal sphincter is located at the end of the esophagus and the stomach, and the corresponding esophageal mucosa has a thickening change. The "Z" line also plays a role in anti-reflux, and the lower esophageal sphincter pressure (LESP) can be increased by vagus nerve excitation. After long-term studies, it can be observed that certain hormones can affect the lower esophageal sphincter pressure.
The high pressure zone formed by the lower esophageal sphincter is the most effective anti-reflux barrier. When the intragastric pressure is increased, the lower esophageal sphincter reactive contraction can exceed the increased intragastric pressure.
In children with lower esophageal sphincter pressure, the stomach contents are easily refluxed through the lower esophageal sphincter. The current standard of gastroesophageal reflux is that the stomach contents are reversed into the lower esophagus. Each cycle is more than 15s, and the pH drops below. 4 (normal pH of the lower esophagus is 5-7), but some experiments have shown that some infants with normal lower esophageal sphincter pressure can also have gastroesophageal reflux, which means that the determination of lower esophageal sphincter pressure alone does not reflect the clinical difference very accurately. .
2. Second barrier - normal peristalsis of the esophagus The normal peristalsis of the esophagus exerts an effective esophageal clearance effect, that is, reflexively produces primary peristalsis, transporting food into the stomach, and sometimes food flows from the stomach to the esophagus, such as the esophagus functioning well. Then the upper end of the esophagus can produce secondary peristalsis, and the food that flows back to the esophagus can be quickly sent to the stomach. Under normal circumstances, the esophagus effectively plays a clearing role through peristalsis, and in some pathological gastroesophageal reflux children It is often seen that the amplitude of esophageal peristalsis is low, and the acid resistance of esophageal mucosa is weakened. Secondary peristalsis is weakened or disappeared. The contents of the stomach can be overflowed upwards through the mouth. Esophagitis often affects the peristaltic ability of the esophagus. The acid content is prolonged.
3. Esophageal mucosal resistance After the gastric contents are reversed into the esophagus, the esophageal mucosa epithelium does not necessarily come into contact with it immediately, because the pre-epithelial defense mechanism - the intramucosal mucus layer, the hydrostatic layer and the mucosal surface HCO-3 can exert physical and chemical barriers. Role, esophageal mucosa is susceptible to acid, pepsin or bile acid damage, when exposed to such substances, mucosal potential difference is easy to change, the protective layer is destroyed, animal experiments and clinical observations prove that esophageal mucosal damage is most likely to occur in gastroesophageal When flowing.
4. The length of the esophageal segment in the abdominal cavity and the His horny esophagus is a soft digestive tract. When the pressure in the abdominal cavity is increased, the esophageal segment of the abdomen is clamped into a flat shape, and the ratio of the esophagus to the effective gastric diameter is 1:5. The esophagus in the abdominal cavity is only needed. When the pressure exceeds 1/5 of the intragastric pressure, it can be closed. The longer the esophageal abdominal segment is, the more perfect the function is. The esophagus of the abdominal cavity of the age <3 months is very short, so it is easy to have gastroesophageal reflux.
The gastroesophageal angle is also called His angle. The normal person has an acute angle and acts as an anti-reflux. It is formed one month after birth. When the esophageal hiatus hernia, this angle becomes obtuse. This angle also depends on the abdominal cavity. Esophageal length.
5. Stomach factors have been reported to confirm that a relatively high proportion of gastroesophageal reflux infants have delayed gastric emptying. This phenomenon also explains why reflux occurs after eating more than other times, gastric emptying, dilatation and gastric contents. Changes can affect the gastroesophageal reflux, and studies have confirmed that normal newborns do not appear normal gastric peristalsis until 12 weeks after birth, maturity takes a period of time, which affects gastric emptying, prone to gastroesophageal Flow, there is a point of peristalsis at the bottom of the stomach. When the esophageal hiatus hernia occurs, the bottom of the stomach is often incorporated into the thoracic cavity, causing the effect of the fundus on the liquid emptying to be affected, and reflux occurs. In addition, the peristaltic wave and the pylorus are open. In the absence of coordination, it can also affect the emptying of the stomach. It is worth mentioning that the stomach may be induced or aggravated by gastroesophageal reflux due to invasive factors. For example, in recent years, children with Zollinger-Ellison syndrome have more gastric acid secretion. Gastroesophageal reflux also increased significantly, reflux alkaline esophagitis, pepsin in the duodenal contents also have damage to the gastric and esophageal mucosa.
Other recent anti-reflux mechanisms, such as the esophageal hiatus and the spring-like clamping action of the esophageal membrane, such as the above various mechanisms, form a normal anti-gastroesophageal reflux effect.
(two) pathogenesis
1. Factors affecting the degree of damage The degree of damage to the esophageal mucosa of reflux esophagitis depends on three factors:
1 the special role of the reflux;
2 the duration of contact with the reflux;
3 The ability of the esophagus to remove the reflux.
2. Pathological morphology Because esophagitis is at different stages of development, the degree of lesions and their corresponding pathomorphological characteristics are also different, usually can be divided into early (slight lesions), medium (inflammation progression and erosion formation), late (chronic ulcer formation and inflammatory hyperplasia).
(1) mild stage of the lesion: histological changes are mainly the basal cell proliferation of the epithelial layer, the thickness is increased, and the thickness ratio of the superficial epithelium is changed; the intrinsic membrane nipple is prolonged and extends to the upper cortex.
(2) Progression of inflammation and formation of erosion: Histological examination showed that the epithelial cells in the lesion area were necrotic and detached, forming a superficial epithelial defect. The epithelial defect was covered by inflammatory cellulose membrane, and neutrophils and lymphocytes were visible under it. Plasma cell infiltration, inflammatory changes are mainly limited to the mucosal muscle layer, but also visible superficial capillary and fibroblast proliferation, the formation of chronic inflammatory or more complex granulation tissue.
3. Ulcer formation and inflammatory proliferative esophageal ulcer are isolated or confluent, and the circulation appears. The histological changes are ulcers extending through the mucosa to the submucosa, rarely invading the muscular layer, and the lesions in the ulcer are layered. The surface is exudative fibrous material, underneath necrotic tissue, neonatal capillaries under the necrotic tissue, proliferating fibroblasts, chronic inflammatory cells or granulation tissue composed of varying amounts of neutrophils. The bottom is the scar tissue formed by the granulation tissue.
Prevention
Infant gastroesophageal reflux prevention
There is no effective preventive measure for this disease. Early detection and early diagnosis are the key to the prevention and treatment of this disease.
Complication
Gastroesophageal reflux complications in infants Complications esophageal stricture aspiration pneumonia an iron deficiency anemia
1. Esophageal stricture: long-term repeated gastroesophageal reflux can cause esophagitis, esophagoscopy can be seen mucosal congestion, edema, erosion, ulceration, fibrous tissue hyperplasia, and then scar formation, leading to esophageal stenosis or even shortening, reported 8% ~ 20% of reflux esophagitis will develop into esophageal stricture, clinical manifestations of dysphagia, dietary changes, such as into solid food cyanosis, like soft food or liquid food, severe eating speed is slightly faster, you can vomit.
2. Bleeding and perforation: Reflux esophagitis due to mucosal congestion and sputum, a small amount of bleeding can occur, long-term can cause different degrees of iron deficiency anemia in children, a small number of serious cases due to esophageal ulcer can occur a large amount of bleeding, and even perforation.
3. Barrett's esophagus: a serious complication of chronic gastroesophageal reflux. Normally, the squamous epithelium at the lower end of the esophagus and the columnar epithelium of the cardia are alternately interlaced to form a dentate line (Z-line) as a chronic reflux esophagitis. Consequences, the columnar epithelial area appears in the lower esophagus, and the normal squamous epithelial area is destroyed, replaced by a more regenerative adjacent area or glandular columnar epithelium, which forms the Barrett epithelium, the metaplastic epithelium has the stomach, the small intestine and the colon The epithelium is histologically similar to mucous cells, goblet cells and villus structures, with clinical manifestations of typical reflux symptoms. Adult Barrett's esophagus with esophageal adenocarcinoma is 30 to 50 times higher than the general population.
Symptom
Infants with gastroesophageal reflux symptoms common symptoms cough, oral ulcers, chest pain, heartburn, snoring
The clinical manifestations of gastroesophageal reflux in children are different, mainly related to the intensity, duration, complications and age of children. Gastroesophageal reflux in children usually has the following four manifestations:
1. The symptoms caused by reflux itself are mainly vomiting, and vomiting after milk is typical. About 85% of children have vomiting in the first week after birth, and 65% of children can be self-administered within six months to one year without clinical treatment. Relieve, in fact, this part of the child is a category of physiological reflux, no special treatment is needed in the clinic, only a few children show repeated vomiting, and gradually increase, which can lead to malnutrition and growth retardation, elderly children can Have acid reflux, snoring and other performances.
2. Symptoms caused by reflux to stimulate the esophagus Because the stomach content or duodenum contains a large number of attack factors, causing damage to the esophageal mucosa, older children may present symptoms such as heartburn, sternal pain, and swallowing chest pain. Patients with severe esophageal lesions may present with hemorrhagic esophagitis and vomiting or vomiting coffee. Most of these children have anemia. The persistent presence of reflux esophageal inflammatory disease can further lead to esophageal stricture and Barrett's esophagus.
3. Stimulating symptoms outside the esophagus In recent years, the most important concern is the causal relationship between gastroesophageal reflux and repeated respiratory infections. About 1/3 of children have recurrent cough due to inhalation of reflux, asthma, bronchitis Symptoms of respiratory infections such as aspiration pneumonia, asthma caused by reflux are not seasonal, often have nocturnal attacks, repeated aspiration pneumonia can lead to pulmonary fibrosis, in neonates, reflux can cause sudden asphyxia or even death, A small number of cases can be expressed as Sandifer syndrome, with a special "cock-like" posture at the time of attack, accompanied by acid reflux, clubbing, low protein and anemia, and individual cases may even be treated in the stomatology department due to oral ulcers and dental diseases. However, the symptoms of reflux are not obvious or neglected. Esophagoscopy may lack the manifestation of esophagitis. After anti-reflux therapy, oral ulcers may be relieved or healed.
Clinical manifestations of gastroesophageal reflux in children vary in severity, and a considerable part of gastroesophageal reflux is a physiological phenomenon. Gastroesophageal reflux in different ages is not the same, so objectively and accurately determine the reflux and its nature is very important.
Examine
Infant gastroesophageal reflux examination
1. The main X-ray of esophageal barium meal imaging in early and mild reflux esophagitis is functional changes of the esophagus and mild mucosal morphological changes, inflammation-induced esophageal spasm contraction, often seen under the esophagus during barium angiography A mild stenosis with a few centimeters of centimeters, with a small amount of tincture remaining above it, can still pass, the stenosis can be expanded to a normal degree, and the stenosis reappears after the sputum is passed. When the erect position is examined, the sputum can pass through the esophagus. However, the emptying time is delayed compared with normal. After the supine position, the normal esophageal peristaltic wave stops at the plane of the aortic arch. Although the expectorant can enter the lower esophagus, only a small amount of tincture enters the stomach during the second swallowing. Inside.
The degree of gastroesophageal reflux seen on the X-ray is not parallel with the severity of reflux esophagitis. Mild and earlier reflux esophagitis on the double contrast phase of the X-ray examination, showing the esophageal mucosal surface and cavity The wall line is rough, the esophageal mucosal surface is needle-pointed or shadowy, and the granular nodules are visible; sometimes the smeared lesions are seen as small punctate ecchymoses; or the woven interlaced lines are seen, and It can be seen that the wide transverse creases in the esophagus are mostly located on the proximal side of the esophageal stricture or deformation.
When scarring stenosis is formed, the shape is mostly thin tubular or funnel-shaped. The narrow segment is mostly regular, the edge is smooth or rough, and it is serrated. The narrow segment is often tightened, straightened, loses normal curvature, and the degree of dilation decreases. The esophageal lumen is slightly enlarged above the stenosis, and ulcers are often seen at the lower end of the esophagus, which is a small shadow with a clear circular border, which is generally shallow.
Esophageal angiography also has a certain diagnostic value for the degree of esophagitis damage. Mc Cauley has a classification table for gastroesophageal reflux X-ray images, which is helpful for discriminating the degree of gastroesophageal reflux.
X-ray classification of gastroesophageal reflux: 0 grade: no gastric content reversed into the lower end of the esophagus; grade I: a small amount of gastric contents flow back into the lower end of the esophagus; grade II: reflux mainly in the esophagus, equivalent to the aortic arch site; The flow is mainly in the pharynx; grade IV: frequent reflux mainly in the pharynx, accompanied by esophageal dyskinesia; grade V: reflux mainly in the pharynx, and inhalation of expectorant.
The positive rate of X-ray diagnosis of gastroesophageal reflux is only 25% to 75%. Meyers et al reported a false negative of 14% and a false positive of 31%, which is related to the amount of meal intake during the examination, especially for newborn babies.
In the X-ray examination, attention should also be paid to whether there is a hiatus hernia, especially slidability. This type of sputum X-ray shows a widening of the vestibular segment of the gastroesophageal tract, part of the gastric mucosa is located on the iliac crest and the ascending esophagus is seen.
2. Esophageal dynamics examination Colley et al. (1957) performed esophageal pressure measurement for the first time in the study of cardiac achalasia. In 1959, Chappell introduced this technique into Europe, and conducted a manometric study on the movement disorder of the giant esophagus. In 1961, Euler The function of the cardia was studied by manometry. Later, Bettex and Cargill successively reported pressure on the hiatal hernia and gastroesophageal reflux. Esophageal manometry has become a widely used method for monitoring esophageal function, evaluation and diagnosis. Therapeutic techniques.
In the diagnosis of gastroesophageal reflux, the main understanding of esophageal movement and lower esophageal sphincter function, the examination is safe, simple and no damage, the neonatal esophageal sphincter pressure is significantly lower in newborns born within 6 days, but later with age It is gradually closer to the value of the group of older children.
In recent years, a large number of reports have reported that the esophageal sphincter pressure in neonates or infants with gastroesophageal reflux is reduced to varying degrees. The length of the lower esophageal sphincter is shorter than that of the normal age group and the lower esophageal sphincter, but there is also a part of the stomach. In neonates with esophageal reflux, the lower esophageal sphincter pressure in infants is normal, while the normal esophageal sphincter pressure in normal children without gastroesophageal reflux is low. The coincidence rate of lower esophageal sphincter pressure and gastroesophageal reflux is about 87%.
3.24h esophageal pH monitoring Spencer was first described in 1969, and then developed by De Meester and Johnson. The test can be eaten or sleep at the same time. The sensitivity of 24h esophageal pH monitoring for diagnosis of gastroesophageal reflux is 88%, and the specificity is 95%. At present, it is the preferred diagnostic method, which can objectively reflect the reflux condition, is safe, easy to operate, and can distinguish between physiological and pathological reflux.
Under normal circumstances, there is no reflux during general sleep, total reflux time <4% monitoring time, average reflux duration <5min and average clearance time <15min, experience of 102 children with esophageal pH monitoring in Shanghai Xinhua Hospital, this is a A new technology with high accuracy and safety and no damage inspection.
4. Esophagus endoscopy This is the most appropriate method for clear esophagitis, combined with pathological examination, can reflect the severity of esophagitis, its sensitivity is 95%, specificity is 41%, but this method can not reflect reflux Severity only reflects the severity of esophagitis, and it is difficult to judge mild (Class I) esophagitis. Therefore, most scholars have suggested that endoscopic findings show that I or II esophagitis does not require mucosal biopsy, but only in microscopic examination or When there is a suspicious change, the Rubin tube is used for biopsy, but in principle, the neonatal period is not performed. The mucosal biopsy is also the main basis for the diagnosis of Barrett's esophagus. The classification of endoscopic reflux esophagitis:
(1) Savary-Miller classification (1978): I: isolated erosive foci and erythema lesions and/or exudation; II: scattered erosions and ulcers, not affecting the entire esophagus; III: erosion and ulcers affect the entire esophagus, However, no stenosis is formed; IV: chronic lesions or ulcers, as well as fibrosis of the esophageal wall, stenosis, short esophagus and/or columnar epithelial esophagus.
(2) Jamieson classification:
0: normal mucosa; I: isolated reddening area; II: ulcer formation; III: esophageal stricture formation.
(3) The 9th World Gastroenterology Conference classification: I: sparse, vertical erosion or ulcer; II: fusion ulcer; III: ulcer fusion into a ring; IV: scar, stenosis.
5. Gastroesophageal nucleus scintigraphy scan recorded the injection of radionuclide 99mTc calibration solution from the stomach tube, and then recorded in the quiet down-slurry scan, this test can provide information on whether there is gastroesophageal reflux, and observe the esophageal function, and can be continuously taken Tablets, while understanding the role of gastric emptying, esophageal clearance, etc., when the presence of labeled nuclide in the lungs, can confirm the respiratory symptoms and gastroesophageal reflux, Rudd prompts the diagnosis of 80% of the sensitivity of children with gastroesophageal reflux.
6. Acid reflux test (Tuttle test) Insert a pH microelectrode probe into the lower esophageal sphincter for about 3cm, then calculate the 0.1mol/L hydrochloric acid solution to 300ml per body surface area per 1.73m, and inject it into the stomach with a nasogastric tube. The pH of the esophagus is monitored. When there is reflux of gastric acid to the esophagus, its pH is <4. The sensitivity of this test is high, and it is not too irritating to the sick child. Some people use apple juice instead of hydrochloric acid solution, and the author thinks it is fake. The positive rate is up to 31%, which is not as injurious as the 24hpH monitoring, and the correctness is high.
There are some shortcomings in the above methods. In recent years, Arasu and Bettex have proposed that the combined application of two methods can better inform the correctness of diagnosis. At present, X-ray esophageal swallowing combined with esophageal dynamics and 24h esophageal pH monitoring Inspection is most commonly used.
Diagnosis
Differential diagnosis of infantile gastroesophageal reflux
The diagnosis of gastroesophageal reflux in children should be based on the following principles:
1 clinically have obvious reflux symptoms, such as vomiting, acid reflux, heartburn or repeated respiratory infections associated with reflux;
2 There is clear objective evidence of gastroesophageal reflux.
