Threshold level of Peptest in diagnosing gastroesophageal reflux disease with extraesophageal symptoms: Evidence from Vietnam

Linh T Nguyen; Tung D Le; Long B Hoang; Vung T Vu; Thang D Nguyen; Hue T M Luu; Phuong N Do; Anh Van Nguyen; Long Van Dao; Mattias Larsson; Linus Olson; Hang V Dao

doi:10.1002/jgh3.13002

Threshold level of Peptest in diagnosing gastroesophageal reflux disease with extraesophageal symptoms: Evidence from Vietnam

JGH Open. 2023 Nov 20;7(12):916-922. doi: 10.1002/jgh3.13002. eCollection 2023 Dec.

Authors

Linh T Nguyen^{1

2}, Tung D Le³, Long B Hoang¹, Vung T Vu¹, Thang D Nguyen¹, Hue T M Luu¹, Phuong N Do^{1

4}, Anh Van Nguyen⁴, Long Van Dao^{1

4

5

6}, Mattias Larsson^{7

8}, Linus Olson^{7

8

9}, Hang V Dao^{1

5

6}

Affiliations

¹ Institute of Gastroenterology and Hepatology Hanoi Vietnam.
² Hanoi Medical University Hanoi Vietnam.
³ Department of Physiology Hanoi Medical University Hanoi Vietnam.
⁴ Hoang Long Clinic Hanoi Vietnam.
⁵ Internal Medicine Faculty Hanoi Medical University Hanoi Vietnam.
⁶ Endoscopy Centre Hanoi Medical University Hospital Hanoi Vietnam.
⁷ Department of Global Public Health Karolinska Institutet Stockholm Sweden.
⁸ Training and Research Academic Collaboration (TRAC), Sweden-Vietnam Hanoi Vietnam.
⁹ Department of Women's and Children's Health Karolinska Institutet Stockholm Sweden.

Abstract

Background and aim: We aimed to evaluate the application of Peptest, a novel technique to detect pepsin in the saliva, and identify its threshold level for the diagnosis of gastroesophageal reflux disease (GERD) with extraesophageal symptoms.

Methods: A cross-sectional study was conducted in two groups: patients with extraesophageal GERD symptoms (symptomatic group divided into GERD and non-GERD groups according to 24-h esophageal pH-impedance monitoring [pH-I] results) and healthy controls. For the symptomatic group, endoscopy, pH 24 h, high-resolution manometry (HRM), and salivary Peptest were performed. For the healthy control group, only Peptest was done. The accuracy of Peptest was compared with that of pH-I by the Lyon consensus criteria.

Results: Chronic laryngitis was the most frequent extraesophageal symptom. On saliva testing, the GERD group had a higher prevalence of positive samples and pepsin concentration than the control group. Between GERD and non-GERD groups, the optimal threshold level was 31.2 ng/mL, with a sensitivity of 86.7% and specificity of 27.5%. The optimal threshold level was 31.4 ng/mL to differentiate GERD from healthy controls, with a sensitivity of 86.7% and specificity of 66.0%. Age, number of total refluxes, DeMeester score, post-reflux swallow-induced peristaltic wave (PSPW) index, and mean nocturnal baseline impedence (MNBI) were associated with pepsin concentration. Regarding HRM metrics, there was no significant difference of pepsin concentration between low/normal upper esophageal sphincter (UES) resting pressure, low/normal lower esophageal sphincter (LES) resting pressure, low/normal 4-s integrated relaxation pressure (IRP4s), and hypomotility/normal motility.

Conclusion: Patients with extraesophageal symptoms had a higher prevalence of positive Peptest. The optimum threshold level of 31.4 ng/mL had high sensitivity and moderate specificity to differentiate between patients with GERD and healthy controls.

Keywords: Peptest; extraesophageal symptoms; gastroesophageal reflux disease; pepsin.