The presentation of GER can be varied, subtle, and differ considerably depending upon the child’s age. GER is caused by transient lower esophageal sphincter relaxation, which allows passive flow of acidic and nonacidic gastric contents into the esophagus.

In infancy, reflux is likely to develop at approximately 1 month of age. Preterm infants may develop the condition even earlier. The incompetence of the lower esophageal sphincter allows the increasing volumes of breast milk or formula to wash up the esophagus, resulting in spitting up or frank vomiting. In addition to a motility disorder, there is now good evidence that food hypersensitivity is a cause of some cases of infant reflux. More severe symptoms occur in babies who reflux and swallow stomach contents, rather than spit up or vomit. These infants develop esophagitis from acidic stomach contents washing up and down the esophagus. Their clinical presentation is one primarily of arching and crying. In addition, they often have nasal congestion, frequent hiccups, and, less frequently, a cough. Parents often interpret the discomfort as “gas.” In primary care settings, clinicians should ask about reflux symptoms at the 1 month well-child visit, because parents rarely recognize the fussiness associated with esophagitis as a symptom of reflux.

If the reflux progresses, untreated, feedings can be disrupted. After beginning to feed, babies pop off the nipple (breast or bottle) to arch and cry. Ultimately, feeding aversion and failure to thrive can result. Parents often report that the only time the babies will feed is when they are almost asleep. The more relaxed state seems to have a protective effect on the amount of refluxing. There is no clear association between apnea or apparent life-threatening events (ALTE) and reflux.

In older children, reflux can present with more classic symptoms of “heartburn” with chest pain and discomfort. Pulmonary symptoms, including recurrent pneumonia, exacerbation of asthma, or chronic cough can also develop. The interplay between asthma and reflux can be confusing. Cases of refractory asthma may warrant diagnostic evaluation for reflux or a diagnostic trial of acid-suppressant therapy.