DIAGNOSTIC EVALUATION
Many tests are available for evaluating patients with suspected GERD. These tests are often unnecessary because the classical symptoms of heartburn and acid regurgitation are sufficiently specific to identify reflux disease and to begin medical treatment. However, this may not always be the case, and the clinician must decide which test to choose to arrive at a diagnosis in a reliable, timely, and cost-effective manner, depending on the information desired.
The simplest and most definitive method for diagnosing GERD and assessing its relation to symptoms (either classical or atypical) is the empiric trial of acid suppression. Unlike other tests that only suggest an association (e.g., esophagitis at endoscopy or positive symptom index on pH testing), the response to antireflux therapy ensures a cause-and-effect relationship between GERD and symptoms. Therefore, it has become the “first” test used in patients with classical or atypical reflux symptoms without “alarm” complaints. The popularity of this approach was aided by the introduction of the PPIs, which, unlike the histamine 2 receptor antagonists (H 2RAs), could drastically reduce the amount of acid reflux into the esophagus. Symptoms usually respond to a PPI trial in 7 to 14 days. If symptoms disappear with therapy and then return when the medication is stopped, GERD may be assumed.
In the reported empiric trials with heartburn, the initial dose of PPI was high (e.g., omeprazole 40 to 80 mg/d) and was given for not less than 14 days. A positive response is defined as at least 50% improvement in heartburn. Using this approach, the PPI empiric trial had a sensitivity of 68% to 83% for determining the presence of GERD. Empiric trials using a 2- to 4-month regimen of PPIs taken twice a day also are commonly used in patients with suspected GERD-associated asthma and GERD complaints related to the ear, nose and throat.
An empiric trial of PPIs for diagnosing GERD has many advantages. The test is office based, is easily performed, is relatively inexpensive, is available to all physicians, and avoids many needless procedures. Disadvantages are few, including a placebo response and uncertain symptomatic end point if symptoms do not resolve totally with extended treatment.
Labels: GERD diagnosis