Introduction: Who Should Seek Diagnostic Testing

If you experience persistent heartburn, pain when swallowing, or the feeling that food is getting stuck in your chest, it may be time to talk to a doctor about diagnostic testing for erosive oesophagitis. This condition doesn’t always announce itself with dramatic symptoms, but ongoing discomfort—especially burning pain behind the breastbone or acid coming back up into your throat—should not be ignored.^[1]

People who have been living with gastroesophageal reflux disease, or GERD, which means stomach contents regularly flow backward into the swallowing tube, are at higher risk. When this happens over and over again, the acid can wear away the protective lining of the oesophagus, creating erosions or small wounds. About 30% of people with GERD develop erosive oesophagitis.^[3]

You should seek medical attention sooner rather than later if you notice more alarming signs. These include difficulty swallowing that makes eating uncomfortable or frightening, chest pain that doesn’t go away, vomiting that contains blood, or black stools that might indicate bleeding inside your digestive system. Young children or infants who refuse to eat, arch their back during feeding, or fail to gain weight properly also need prompt evaluation.^[2][4]

People undergoing radiation therapy for chest cancers, those taking certain medications like bisphosphonates for bone health or antibiotics like tetracycline, and individuals with weakened immune systems due to HIV, diabetes, or cancer treatments should be aware they face higher risk. In these groups, symptoms may develop more quickly or be more severe. Testing can help catch problems early before they progress to complications like narrowing of the oesophagus or more dangerous conditions.^[1][3]

Classic Diagnostic Methods

The most important and reliable way to diagnose erosive oesophagitis is through a procedure called endoscopy, also known as esophagogastroduodenoscopy or EGD. This test allows a doctor to directly look inside your oesophagus and see exactly what is happening. During an endoscopy, you receive medication to help you relax, and then a thin, flexible tube equipped with a tiny camera is gently guided down your throat and into your oesophagus. The camera sends real-time images to a screen, letting the doctor see whether there is inflammation, erosion, ulcers, or other damage to the lining.^[9][18]

What makes endoscopy so valuable is that it doesn’t just show whether erosive oesophagitis is present—it also reveals how severe it is. Doctors can see the size and location of erosions and determine whether there are complications like narrowing (strictures) or abnormal tissue changes. This visual information is critical because it helps distinguish erosive oesophagitis from other forms of oesophageal disease, including nonerosive reflux disease where symptoms occur but no visible damage is seen, or Barrett’s oesophagus, a condition where the lining changes in a way that increases cancer risk.^[3][11]

During the endoscopy, the doctor can also take small tissue samples, called biopsies. These samples are sent to a laboratory where they are examined under a microscope. Biopsies help confirm the diagnosis and rule out other causes of oesophageal inflammation, such as infections from yeast, viruses, or bacteria, or allergic reactions that cause a different type of inflammation called eosinophilic esophagitis. The microscopic examination can also detect early signs of more serious tissue changes that might need closer monitoring.^[2][9]

Before deciding on endoscopy, your doctor will first take a detailed medical history and perform a physical examination. They will ask you about your symptoms—when they started, how often they occur, what makes them better or worse, and whether you have any known risk factors like long-standing reflux or medication use. This conversation helps your doctor decide whether endoscopy is necessary or whether other tests might be tried first.^[4]

In some cases, especially when classic heartburn and reflux symptoms are present without alarm signs like difficulty swallowing or bleeding, doctors may initially suggest a trial of acid-reducing medication without performing endoscopy right away. If symptoms improve significantly, this supports the diagnosis. However, if symptoms persist despite treatment, or if there are concerning features from the start, endoscopy becomes essential to see what is actually happening inside.^[12]

Another test that may be used is called a barium swallow, also known as an upper gastrointestinal series. For this test, you drink a liquid containing a compound called barium, which shows up clearly on X-rays. As the barium moves down your oesophagus and into your stomach, X-ray images are taken. This test can reveal abnormalities in the shape or movement of the oesophagus, such as narrowing or strictures, and can detect large ulcers or masses. However, it cannot show the fine details of the lining or allow tissue samples to be taken, so it is less commonly used than endoscopy when erosive oesophagitis is suspected.^[9][18]

There is also a newer, less invasive option called an esophageal capsule test. This involves swallowing a capsule attached to a string. The capsule dissolves in your stomach and releases a small sponge, which the doctor then pulls back out through your mouth using the string. As it comes up, the sponge collects cells from the oesophagus lining, which are then examined in a lab. This test can provide information about inflammation without requiring full endoscopy, though it is not as widely available and may not give as complete a picture as looking directly with a camera.^[9][18]

If infection is suspected, especially in people with weakened immune systems, additional testing may be done. This could include special stains or cultures of biopsy samples to look for yeast like Candida, viruses like herpes simplex or cytomegalovirus, or bacteria. Identifying an infectious cause is important because it requires different treatment than acid-related erosive oesophagitis.^[1][2]

Diagnostics for Clinical Trial Qualification

When patients are being considered for enrolment in clinical trials testing new treatments for erosive oesophagitis, they must meet specific diagnostic criteria. These criteria ensure that everyone in the trial has a confirmed diagnosis and that the disease is at a similar stage, which makes it easier to measure whether a treatment is working. The diagnostic process for clinical trial qualification is more standardized and detailed than what might be needed for routine clinical care.^[12]

The cornerstone of trial qualification is almost always an upper endoscopy with biopsy. This test must confirm the presence of erosions in the oesophagus lining and document their severity according to a recognized grading system. The most commonly used system is called the Los Angeles Classification, which divides erosive oesophagitis into grades from A to D based on the size and extent of the erosions. Grade A represents the mildest form with small, isolated breaks in the lining, while Grade D represents the most severe, with erosions that go all the way around the inside of the oesophagus. Many clinical trials specify which grades they will accept—for example, some trials may only include patients with more advanced grades C or D because these are the patients who have the most difficulty getting their condition under control with standard treatments.^[7][11]

In addition to confirming erosions, the endoscopy must rule out other conditions that could mimic erosive oesophagitis or that would make a patient ineligible for the trial. This includes checking for Barrett’s oesophagus, oesophageal cancer, eosinophilic esophagitis, or infectious causes of inflammation. Biopsy samples are carefully examined under a microscope to exclude these other diagnoses.^[8][14]

Clinical trials often require that patients have symptoms as well as visible erosions. This is because the goal of many trials is not just to heal the oesophagus but also to relieve symptoms like heartburn and regurgitation. Patients may be asked to complete symptom questionnaires or diaries before they can be enrolled, documenting how often and how severely they experience symptoms. This helps researchers understand whether the treatment improves quality of life, not just what is seen on endoscopy.^[19]

Some trials also require evidence that a patient has not responded well to standard treatment before they can participate. For example, a trial might only accept patients who still have erosions or symptoms despite taking proton pump inhibitors (PPIs), which are the most commonly used medications for erosive oesophagitis, for at least eight weeks. This is known as having refractory disease. To prove this, patients may need to provide documentation of their previous medication use and may undergo a repeat endoscopy after a period of treatment to show that erosions have not fully healed.^[7][8]

Blood tests and other laboratory work are also commonly required as part of trial screening. These tests check for general health problems that might make it unsafe for someone to participate, such as liver or kidney disease, or that might interfere with the study. For example, if a trial is testing a medication that is processed by the liver, doctors need to know whether your liver is functioning normally before you start taking it.^[24]

Patients in clinical trials are often monitored more closely than those receiving routine care. This means they may need to undergo repeat endoscopies at specific intervals during the trial to measure whether erosions are healing, along with repeated symptom assessments and laboratory tests. While this level of monitoring can be more demanding, it also means that patients in trials receive very thorough medical attention and contribute valuable information that may help future patients.^[12][14]