Acid Perfusion Test: A Useful Test for Evaluating Esophageal Acid Sensitivity

Abstract

The acid perfusion test (APT) is a test of esophageal acid sensitivity. In gastroesophageal reflux disease (GERD), the APT has largely been superseded by indexes derived from 24-hr esophageal pH monitoring: symptom index (SI), symptom sensitivity index (SSI), and symptom association probability (SAP). To evaluate the role of APT in patients with GERD we compared values of SI, SSI, and SAP in 126 APT+ and 146 APT- patients. Median values for SI, SSI, and SAP were higher in the APT+ compared with the APT- group (P < 0.001). More patients had a positive SI, SSI, and SAP in the APT+ compared with the APT- group (SI, P < 0.0001; SSI and SAP, P < 0.001). Patients with a negative APT were unlikely to have symptoms caused by acid reflux (negative predictive value, 86%). APT may be useful in detecting acid sensitivity in patients who do not report symptoms on 24-hr esophageal pH monitoring.

In vivo evaluation of acid-induced changes in oesophageal mucosa integrity and sensitivity in non-erosive reflux disease

“…We already know that patients with FH (who by definition do not have reflux-induced symptoms) display a high ‘positive’ rate when the acid sensitivity test is used as a diagnostic tool 25. Within our FH group, patients who perceived acid perfusion had lower baseline impedance than those who did not, suggesting that peripheral factors may still play a role in their acid perception.…”

Non-Erosive Reflux Disease (NERD), Symptomatic and Asymptomatic Erosive Reflux Disease (ERD): From Hypersensitive to Hyposensitive Esophagus

“…More recent studies comparing with prolonged pH monitoring have also shown conflicting results. King et al [12] showed that in GERD patients with a positive acid perfusion test, there was a significantly higher symptom index and symptom association probability compared to those with a negative test. In another study, Jung et al [13] however, could not show an association between a positive Bernstein's test and a positive symptom index on prolonged pH measurement.…”

Signal detection theory approach to gastroesophageal reflux disease: a new method for symptom analysis of impedance-pH data

“…SI and SSI provide percent of reflux related symptom and symptom‐related reflux episodes, respectively. Although formal validation have not been performed, there have been several clinical validation studies that demonstrate SI and SSI identify patients groups that correspond to acid perfusion test and respond to PPI treatment or surgical treatment . However, these indices are not suitable to create causal relationship between reflux and symptom because of symptom report bias, that is, the patient's tendency either to emphasize or to deny the presence of symptoms .…”