How Is GERD Diagnosed? Endoscopy, pH Tests and What to Expect

If you have heartburn that keeps coming back, you may wonder whether you will need an endoscopy or other scans. For many people, the answer is no. This article explains how doctors usually reach a diagnosis and when extra tests are used, based on information from the US National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).

Starting with symptoms and history

According to NIDDK, doctors usually diagnose gastroesophageal reflux (GER) and gastroesophageal reflux disease (GERD) from your symptoms and medical history. In many cases the doctor may suggest medicine and lifestyle changes first, without any testing. Being able to describe your symptoms clearly helps, for example when they happen, what seems to set them off and what you have already tried.

When are tests recommended?

NIDDK says tests may be advised when:

• A complication of GERD is suspected
• Another condition could be causing similar symptoms
• Symptoms do not improve with treatment

Your doctor may also refer you to a gastroenterologist, a doctor who specialises in the digestive system.

Upper GI endoscopy

In an upper GI endoscopy, a doctor passes a flexible tube with a camera on the end through the mouth to look at the food pipe, stomach and the first part of the small intestine (the duodenum). NIDDK explains that this test can check for complications or for other causes of your symptoms. The doctor may also take small tissue samples (biopsies), which a pathologist later examines under a microscope.

Some practical points from NIDDK's page on the test:

• You will usually be asked not to eat or drink for up to 8 hours beforehand, or to follow the specific instructions you are given.
• Tell the doctor about all your medicines, vitamins and supplements, including aspirin, NSAIDs and blood thinners. Some may need to be adjusted or paused, but only on your doctor's advice.
• You may get a sedative through a vein, and a throat spray or gargle may be used to reduce gagging.
• The test usually takes 10 to 20 minutes, and you will normally stay about an hour while the sedative wears off.
• Arrange for someone to take you home, because you cannot drive after sedation.

Esophageal pH monitoring

NIDDK describes pH monitoring as the most accurate way to detect stomach acid in the food pipe. There are two main kinds:

• Catheter monitoring: a thin tube is passed through the nose into the food pipe to measure acid and non-acid reflux.
• Capsule monitoring: during an endoscopy, a small wireless capsule is attached to the lining of the food pipe to measure acid reflux.

The person wears a monitor that records their diet, sleep and symptoms alongside the readings. Doctors use this test to confirm GERD or to check whether treatment is working.

Possible risks of endoscopy

NIDDK says the overall risk of upper GI endoscopy is low. Possible problems include a reaction to the sedative, bleeding, and, rarely, a hole (perforation) in the lining of the digestive tract. Bleeding is usually minor and stops by itself.

When to see a doctor

See a doctor if you suspect GERD or your symptoms continue despite over-the-counter medicines or lifestyle changes. NIDDK also lists warning signs that need prompt attention: chest pain, loss of appetite, repeated vomiting, trouble or pain with swallowing, vomit that contains blood or looks like coffee grounds, black or bloody stools, and unexplained weight loss.

After an endoscopy, NIDDK advises seeking care right away for trouble breathing, worsening swallowing problems or throat pain, vomiting blood, worsening chest or belly pain, black or bloody stools, or fever.

In an emergency, call your local emergency number (112 in India, 911 in the United States).