RESUMEN
BACKGROUND AND AIM: The measurement of esophageal acid exposure time (AET) using combined multichannel intraluminal impedance-pH (MII-pH) tests is the gold standard for diagnosing gastroesophageal reflux disease (GERD). However, this catheter-based 24-h test can cause considerable patient discomfort. Our aim is to identify factors affecting AET and to develop a scoring model for predicting AET abnormalities before conducting the MII-pH test. METHODS: Of the 366 patients who underwent MII-pH test at two facilities in Japan and Vietnam, 255 patients who also had esophagogastroduodenoscopy and high-resolution manometry were included in this study. Logistic regression analysis was conducted using risk factors for AET > 6% identified from a derivation cohort (n = 109). A scoring system predicting AET > 6% was then constructed and externally validated with a separate cohort (n = 146). RESULTS: Three variables were derived from the prediction model: male gender, Hill grades III-IV, and weak mean distal contractile integrals. Based on these scores, patients were classified into low (0 point), intermediate (1-3 points), and high (4 points) risk groups. The probabilities of having an AET > 6% were 6%, 34%, and 100% for these groups, respectively. A score of < 1 excluded patients with abnormal AET, with a negative predictive value of 93.8% in the derivation cohort and 80.0% in the validation cohort. CONCLUSIONS: We derived and externally validated a prediction model for abnormal AET. This system could assist in guiding the appropriate treatment strategies for GERD.
RESUMEN
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.