Gastroesophageal reflux disease (GERD) is the pathological damage caused by the reflux of stomach and/or duodenal contents into the esophagus.
Etiology and pathology]
GERD is caused by a number of factors, including decreased anti-reflux function of the lower esophagus and increased aggressive factors in the refluxed material. The lower esophageal anti-reflux mechanism consists of the lower esophageal sphincter (LES), the diaphragmatic esophageal ligament, the acute angle between the esophagus and the gastric fundus (His angle) and the defense system of the esophageal mucosal epithelium, among which the anti-reflux function of the LES is the most important.
Pathological reflux occurs on the basis of the decline of the above-mentioned defense mechanisms, and the attack factors in the reflux material cause damage to esophageal tissues, among which gastric acid and pepsin have the strongest damaging effect, causing damage to the esophageal mucosa and the occurrence of reflux esophagitis, esophageal stricture, and even esophageal shortening and Barrett’s esophagus.
Since the maturation of the lower esophageal sphincter is not completed until the end of pregnancy and one week after birth, the majority of gastroesophageal reflux in newborns is physiological and decreases with age after birth. Pathological reflux accounts for only l/500 of gastroesophageal reflux in newborns.
Clinical manifestations
The clinical manifestations of pediatric GERD vary in severity and are related to the intensity, duration, presence of complications and the age of the pediatric patient.
1, the symptoms caused by the reflux itself mainly manifested as vomiting, vomiting after feeding as a typical performance, about 85% of the children after birth the first week that vomiting, 65% of the children without clinical treatment can be in six months to a year on their own remission, belong to the category of physiological reflux. Only a few children show recurrent vomiting, which gradually worsens and leads to malnutrition and growth retardation. Older children may have acid reflux, hiccups and other manifestations.
2. Symptoms caused by reflux stimulating the esophagus Because the stomach contents or duodenal contents, containing a large number of attack factors, cause damage to the esophageal mucosa, older children may show symptoms such as heartburn, retrosternal pain, swallowing chest pain, etc. Heavy esophageal lesions can be manifested as reflux esophagitis and vomiting blood or coffee-like material, such children are often seen anemic. If the symptoms of reflux esophagitis persist, it may lead to complications such as esophageal stricture and Barrett’s esophagus.
In recent years, most attention has been paid to the causal relationship between gastroesophageal reflux and recurrent respiratory infections. About 1/3 of children have recurrent symptoms of respiratory infections such as choking and coughing, asthma, bronchitis and aspiration pneumonia due to inhalation of reflux.
In newborns, reflux can cause sudden asphyxia or even death. In a few cases, it may manifest as Sandifer’s syndrome, with a special “cock’s head-like” posture, acid reflux, pestle finger, low protein and anemia.
4. Complications caused by reflux
(1) Esophageal stricture.
Long-term recurrent gastroesophageal reflux can cause esophagitis, and esophagoscopy can reveal mucosal congestion, edema, erosion, ulceration, fibrous tissue hyperplasia, and then scar formation, leading to esophageal stricture or even shortening. Some reports show that 8% to 20% of reflux esophagitis will develop into esophageal stricture.
(2) Bleeding and perforation.
Reflux esophagitis can occur with small amounts of bleeding due to mucosal congestion and erosion, which can cause varying degrees of iron deficiency anemia in pediatric patients over time. In a few severe cases, larger amounts of bleeding and even perforation can occur due to esophageal ulceration.
(3) Barrett’s esophagus.
A serious complication of chronic gastroesophageal reflux, the squamous epithelial area of the lower esophagus is destroyed and a columnar epithelial area appears, which is then replaced by a more regenerative adjacent area or adenoductal columnar epithelium, forming Barrett’s epithelium. In adults Barrett’s esophagus combined with esophageal adenocarcinoma is 30 to 50 times higher than the general population.
Diagnosis
The clinical manifestations of pediatric GERD vary in severity, and a significant portion of reflux is a physiological phenomenon, so it is important to determine reflux and its nature objectively and accurately.
1.Diagnostic principles of pediatric GERD
(1) There are obvious clinical symptoms of reflux, such as vomiting, acid reflux, heartburn or recurrent respiratory infections associated with reflux, etc;
② There is clear objective evidence of GERD.
2, pediatric GERD examination means GERD objective examination methods, such as barium meal examination, endoscopy, gastroesophageal radionuclide scan, gastroesophageal manometry, gastroesophageal pH monitoring, as well as chest pain test, acid reflux test, etc.. Dynamic gastroesophageal pH monitoring is currently considered the gold standard for the diagnosis of GERD. Esophageal pH <4 is generally used as the criterion for determining GERD, with the following main indicators.
①The percentage of esophageal pH<4 in the total monitoring time (called Reflux index, RI);
②The number of times reflux occurred;
③The number of times reflux lasted >5 minutes;
④The longest duration of reflux;
⑤ area under the curve for pH<4.
The sensitivity of radionuclide gastroesophageal scintigraphy, which examines the diagnosis of pediatric GERD, is 80%.
Esophageal endoscopy is a direct and reliable means of diagnosing reflux esophagitis, and combined with pathological examination can clarify the severity of esophagitis.
In view of some limitations of objective examination methods, it is now advocated to combine two or more of these methods for testing to improve the accuracy of diagnosis. A combination of barium X-ray, esophageal manometry, dynamic pH monitoring and esophageal endoscopy is often used to diagnose pediatric GERD.
【Treatment
1.The principles of medical treatment for pediatric GERD
(1) General treatment: including postural therapy and adjustment of diet and feeding. The literature reports that the best position for treatment is prone with the head raised 30°. This position has the lowest frequency of reflux because the esophagogastric junction is higher than the bottom of the stomach. Older children should sleep in the right lateral position with the upper body elevated, a position that facilitates gastric emptying. Dietary adjustments include feeding with sticky, pasty foods, reducing the amount of food eaten at a time, and reducing the amount of fat, chocolate or coffee in the food.
(2) Pharmacological treatment: including two categories of pro-gastrointestinal dynamics and acid suppressants, as well as mucosal protective agents, etc. The combined application is more effective. GERD is a dynamic disease of the upper gastrointestinal tract, theoretically should first improve gastrointestinal dynamics. The main role of acid suppressants is to reduce the irritation of H+ in the reflux to the esophageal mucosa, reduce the symptoms and treat reflux esophagitis. Mucosal protective agents can be used to protect the damaged esophageal mucosa, reduce reflux symptoms and treat reflux esophagitis.
Although drug therapy can more obviously control the symptoms of GERD and treat reflux esophagitis, it is easy to relapse after stopping the drug because the cause of the disease is not removed. Surgery should be considered for those who have organic lesions of GERD, such as congenital diaphragmatic hernia or those who have repeatedly failed in medication treatment.