Initial Diagnostic Test for Suspected Gastroesophageal Reflux Disease (GERD)

Upper endoscopy (esophagogastroduodenoscopy or EGD) is the initial test of choice for suspected gastroesophageal reflux disease. 1

Diagnostic Approach to GERD

Initial testing to evaluate for reflux should be tailored to the patient's clinical presentation and typically includes upper endoscopy as the first-line diagnostic test 1
Endoscopy is currently the initial investigation of choice for GERD in clinical practice and clinical research 2
Upper endoscopy allows direct visualization of the esophageal mucosa to determine the presence and severity of injury from reflux of gastric contents 1

Upper endoscopy is indicated at first presentation for patients with alarm symptoms referable to the upper gastrointestinal tract 2
Endoscopy allows evaluation of inflammation in the esophageal mucosa attributable to GERD and excludes other conditions with symptoms that can mimic GERD 1
Endoscopic findings of reflux esophagitis should be classified according to an accepted grading scale (such as the Los Angeles or MUSE classification) 2, 3

40-60% of patients with typical reflux symptoms do not have esophageal erosions and are considered to have "endoscopy negative reflux disease" (ENRD) 2
Endoscopy is not the final arbiter for diagnosing reflux disease and is not a necessary prerequisite to therapy in all cases 2
Currently, there is no single diagnostic tool that can conclusively identify gastroesophageal reflux as the cause of extraesophageal symptoms 1

Ambulatory esophageal reflux monitoring (pH or pH-impedance) should be considered in patients with suspected extraesophageal manifestations of GERD who fail PPI therapy 1
Barium swallow (option A) may identify structural changes such as stricturing or esophageal shortening but is not the first-line test for GERD 2, 4
Esophageal manometry (option D) is primarily used to evaluate esophageal peristalsis and lower esophageal sphincter function, mainly in GERD patients being considered for surgery 4
Gastric pH monitoring (option C) is not typically used as an initial diagnostic test for GERD 1

In patients with suspected extraesophageal manifestation of GERD but without typical GERD symptoms, consideration should be given toward diagnostic testing before initiating PPI therapy 1
For patients with typical GERD symptoms, an initial PPI trial (starting with single-dose and titrating up to twice daily if needed) is reasonable before proceeding to diagnostic testing 1
Repeat endoscopy should be performed in patients with severe erosive esophagitis after at least an 8-week course of PPI therapy to exclude underlying Barrett's esophagus or dysplasia 3

Relying solely on symptom improvement with PPI therapy to confirm GERD diagnosis, as this may result from mechanisms other than acid suppression 1
Failing to obtain tissue samples to confirm endoscopically suspected Barrett's esophagus 3
Obtaining tissue samples from endoscopically normal tissue to diagnose GERD or exclude Barrett's esophagus in adults is not recommended 3