Gastroesophageal reflux in childhood.

Gastroesophageal reflux (GER) is one of the most frequent symptomatic clinical disorders affecting the gastrointestinal tract of infants and children. During the past 2 decades, GER has been recognized more frequently because of an increased awareness of the condition and also because of the more sophisticated diagnostic techniques that have been developed for both identifying and quantifying the disorder. Gastroesophageal fundoplication is currently one of the three most common major operations performed on infants and children by pediatric surgeons in the United States. Normal gastroesophageal function is a complex mechanism that depends on effective esophageal motility, timely relaxation and contractility of the lower esophageal sphincter, the mean intraluminal pressure in the stomach, the effectiveness of contractility in emptying of the stomach, and the ease of gastric outflow. More than one of these factors are often abnormal in the same child with symptomatic GER. In addition, in patients with GER disease, and particularly in those patients with neurologic disorders, there appears to be a high prevalence of autonomic neuropathy in which esophagogastric transit and gastric emptying are frequently delayed, producing a somewhat complex foregut motility disorder. GER has a different course and prognosis depending on the age of onset. The incompetent lower esophageal sphincter mechanism present in most newborn infants combined with the increased intraabdominal pressure from crying or straining commonly becomes much less frequent as a cause of vomiting after the age of 4 months. Chalasia and rumination of infancy are self-limited and should be carefully separated from symptomatic GER, which requires treatment. The most frequent complications of recurrent GER in childhood are failure to thrive as a result of caloric deprivation and recurrent bronchitis or pneumonia caused by repeated pulmonary aspiration of gastric fluid. Children with GER disease commonly have more refluxing episodes when in the supine position, particularly during sleep. The reflux of acid into the mid or upper esophagus may stimulate vagal reflexes and produce reflex laryngospasm, bronchospasm, or both, which may accentuate the symptoms of asthma. Reflux may also be a cause of obstructive apnea in infants and possibly a cause of recurrent stridor, acute hypoxia, and even the sudden infant death syndrome. Premature infants with respiratory distress syndrome have a high incidence of GER. Esophagitis and severe dental carries are common manifestations of GER in childhood. Barrett's columnar mucosal changes in the lower esophagus are not infrequent in adolescent children with chronic GER, particularly when Heliobacter pylori is present in the gastric mucosa. Associated disorders include esophageal dysmotility, which has been recognized in approximately one third of children with severe GER. Symptomatic GER is estimated to occur in 30% to 80% of infants who have undergone repair of esophageal atresia malformations. Neurologically impaired children are at high risk for having symptomatic GER, particularly if nasogastric or gastrostomy feedings are necessary. Delayed gastric emptying (DGE) has been documented with increasing frequency in infants and children who have symptoms of GER, particularly those with neurologic disorders. DGE may also be a cause of gas bloat, gagging, and breakdown or slippage of a well-constructed gastroesophageal fundoplication. The most helpful test for diagnosing and quantifying GER in childhood is the 24-hour esophageal pH monitoring study. Miniaturized probes that are small enough to use easily in the newborn infant are available. This study is 100% accurate in diagnosing reflux when the esophageal pH is less than 4.0 for more than 5% of the total monitored time.