To Test for Reflux

Barium swallow or Upper GI series

This is a special x-ray that allows doctors to follow food down the baby's esophagus, through the stomach and into the first part of the small intestine. The baby is fed a chalky-white liquid called barium. A video x-ray machine follows the barium through the upper intestinal tract and lets doctors see if there are any abnormal twists, kinks or narrowing of the upper intestinal tract. This x-ray test does not, however, give doctors much information on how the intestine works when food is in it and therefore it is not a very reliable way of diagnosing gastroesophageal reflux.

Many children with severe symptoms of gastroesophageal reflux will not demonstrate reflux on a barium swallow (poor sensitivity) and conversely, children who demonstrate reflux on a barium swallow have no symptoms of gastroesophageal reflux (poor specificity). Perhaps more important, the severity of reflux observed on a barium swallow does not help to predict the severity of symptoms of reflux nor does it help to predict the ultimate outcome. Less than 30% of adults with symptoms of chronic gastroesophageal reflux demonstrate reflux on a barium swallow and less than 30% of adults with esophagitis as a result of chronic gastroesophageal reflux will demonstrate reflux on a barium swallow.

pH Probe Study

With this test, a small wire with an acid sensor is placed through the infants nose down to the bottom of the esophagus. The sensor can detect when acid from the stomach is "refluxed" into the esophagus. This information is generally recorded on a computer. Usually, the sensor is left in place between 12 and 24 hours. At the conclusion of the test, you are able to determine how often the infant "refluxes" acid into his or her esophagus and whether he or she has any symptoms when that occurs.

The biggest problem with this test is that the severity of the reflux as measured by pH probe often doesn't correlate with the severity of symptoms . . . that is, some of infants with very frequent vomiting will have normal pH probe studies. Perhaps more important, the severity of reflux measured by a pH probe does not help to predict the ultimate outcome. While pH probe analysis is abnormal in nearly 80% of infants with mild symptoms of reflux (i.e. occasional spitting and vomiting), one third of the infants with severe symptoms have a normal pH probe study!  Moreover, less than 40% of infants with severe esophagitis due to chronic gastrophageal reflux will demonstrate abnormal pH probe studies.

Perhaps the greatest potential value of pH probe analysis is in trying to correlate gastroesophageal reflux with unusual or persistent symptoms such as apnea, stridor, coughing or wheezing, choking, gagging, or unexplained irritability. If these symptoms occur frequently enough, a pH probe analysis can be performed to determine if these symptoms occur at the same time as episodes of acid reflux into the esophagus.