Pharmacogenetic Testing in Children With Persistent Gastroesophageal Reflux Disease

Inclusion Criteria: * persistent gastrointestinal symptoms (GI) suggestive of gastro esophageal reflux disease (GERD) despite adequate therapy * persistent evidence of abnormal reflux indices' and acid exposure on esophageal multichannel pH impedance study despite adequate therapy * persistent endoscopic evidence of reflux esophageal disease despite adequate therapy Exclusion Criteria: * children with eosinophilic esophagitis diagnosis * children with any esophageal surgical intervention like fundoplication, tracheoespahgeal fistula repair or esophageal atresia repair * children with other diseases that can affect the esophagus, like Crohn's disease or food protein-induced enterocolitis syndrome (F-PIES) * Children who do not have research authorization in their chart