In someone with refractory GERD, what is the most appropriate INITIAL diagnostic study?

• A. EGD
• B. Esophageal manometry
• C. 24 hr pH monitoring
• D. Barium swallow study

Answer: (B)

In refractory GERD, the first test you want to obtain is an evaluation of esophageal motility and LES function. Esophageal manometry measures the strength and coordination of esophageal contractions, as well as the resting pressure and relaxation of the lower esophageal sphincter. This information is crucial because it helps determine whether a motility disorder or weak LES—conditions that can mimic GERD symptoms or affect treatment decisions—explains persistent symptoms. It also matters if surgical therapy is being considered, since poor peristalsis or a hypotensive LES can predict a worse outcome with fundoplication.

If manometry shows normal motility and adequate LES function, you can then use pH monitoring to quantify ongoing acid reflux and correlate it with symptoms to confirm GERD as the cause of symptoms despite therapy. Endoscopy can still be helpful to look for mucosal damage or complications, and a barium swallow can assess anatomy, but they don’t inform treatment planning as directly about motility and LES function when GERD is refractory.