Pepsin and pH of Gastric Juice in Patients With Gastrointestinal Reflux Disease and Subgroups

GOAL

The aim of this study was to investigate the pepsin values and pH results of gastric juice among the subtypes of gastroesophageal reflux disease (GERD) and functional heartburn.

BACKGROUND

The major destructive agents of GERD on the esophageal epithelium are gastric acid and pepsin. No precise information about pepsin concentration in gastric juice exists.

STUDY

Ninety patients with GERD, 39 erosive reflux disease (ERD) Los Angeles (LA) grade A/B, 13 ERD LA grade C/D, 19 nonerosive reflux disease (NERD), 8 esophageal hypersensitivity, 11 functional heartburn, and 24 healthy controls were included in the study. During endoscopy gastric juices from the patients were aspirated and their pH readings immediately recorded. Gastric juice samples were analyzed using Peptest, a lateral flow device containing 2 unique human monoclonal antibodies to detect any pepsin present in the gastric juice sample.

RESULTS

The highest mean gastric pepsin concentration (0.865 mg/mL) and the lowest median gastric pH (1.4) was observed in the LA grade C/D group compared with the lowest mean gastric pepsin concentration (0.576 mg/mL) and the highest median gastric pH (2.5) seen in the NERD group. Comparing pH, the NERD patient group was significantly higher (P=0.0018 to P=0.0233) when compared with all other GERD patient groups.

CONCLUSIONS

The basal gastric pepsin level in the healthy control group was comparable to literature values. There was good correlation and a significant linear relationship between the gastric pepsin level and gastric pH within the patient groups. The severity of the GERD disease is related to the lowest pH and the highest pepsin concentration in gastric juice.

Validation of Peptest™ in Patients with Gastro-Esophageal Reflux Disease and Laryngopharyngeal Reflux Undergoing Impedance Testing

BACKGROUND AND AIMS

Pepsin in the gastric refluxate is a marker for a prior reflux event and rapid detection might be achieved using the Peptest™, an in vitro diagnostic medical device. The aim of this study was to validate the use of Peptest™ to reliably diagnose reflux in patients with gastro-esophageal reflux disease (GERD) and laryngopharyngeal reflux (LPR) disease diagnosed with multichannel intraluminal impedance/ pHmetry (MII-pH).

METHODS

20 reflux patients were recruited of whom 10 had classical GERD and 10 had LPR. All patients underwent MII-pH and provided expectorated saliva samples when a MII-pH reflux event was observed, or reflux symptoms were experienced, and all were tested for the presence of pepsin using the Peptest™.

RESULTS

Pepsin was detected in 31 out of 45 samples (68.9%). At least 1 positive pepsin result was seen in 16 patients (80%) and this was the same, irrespective of the GERD or LPR diagnosis. Peptest™ had a positive predictive value of 69% to detect MII-pH reflux events.

CONCLUSIONS

Peptest™ is a good first-line diagnostic procedure to use in reflux sufferers to confirm the presence of reflux.

Validation in China of a non-invasive salivary pepsin biomarker containing two unique human pepsin monoclonal antibodies to diagnose gastroesophageal reflux disease

OBJECTIVES

Peptest is a new non-invasive reflux diagnostic test based on lateral flow technology that containing two highly specific human pepsin monoclonal antibodies for detecting pepsin, a biomarker for reflux disease. The primary aim of this multicenter clinical study was to validate the efficacy of Peptest in patients diagnosed with gastroesophageal reflux and healthy controls in China.

METHODS

Patients with suspected gastroesophageal reflux underwent an endoscopy and were classified into non-erosive reflux disease and erosive esophagitis subgroups. A healthy control group was also recruited. All participants were given a reflux disease questionnaire-patients scoring greater than 12 and controls scoring zero. All participants provided a postprandial saliva sample and most patients gave an additional post-symptom sample for pepsin analysis.

RESULTS

Altogether 1032 participants aged between 19 and 78 years were recruited. They consisted of 488 patients with non-erosive reflux disease, 221 with erosive esophagitis and 323 healthy controls. The number of postprandial and post-symptom samples analyzed totaled 1031 and 692, respectively. The results across all centers showed an overall pepsin-positive sensitivity of 85%, a specificity of 60%, a positive predictive value of 82%, a negative predictive value of 65% and a positive likelihood ratio of 2.12.

CONCLUSION

The sensitivity of Peptest was high, but the specificity achieved in some centers was low, resulting overall in only a moderate specificity. Further diagnostic investigative studies are warranted.