At present，many studies showed that food intolerance (FI) is one of the important factors for the occurrence and aggravation of irritable bowel syndrome (IBS). The FI in IBS patients is related to low grade inflammation of intestine. Fermentable oligo‑，di‑，monosaccharides and polyols (FODMAPs) diet can improve the symptoms of IBS and provide a new idea for exploring the pathogenesis and treatment of IBS. This article reviewed the advances in study on role of FI in pathogenesis of IBS.

Objective:To explore the efficacy and influencing factors of linaclotide in patients with functional defecation disorder (FDD).Methods:From June 1, 2021 to February 28, 2023, at the First Affiliated Hospital of Nanjing Medical University, 160 patients with FDD were enrolled and randomly divided into linaclotide group and polyethylene glycol group by using a random number table method, with 80 cases in each group, and the treatment course both was 4 weeks. The efficacy, weekly complete spontaneous bowel movement (CSBM), patient assessment of constipation symptom (PAC-SYM), numerical rating scale (NRS), Zung′s self-rating anxiety scale (SAS) and Zung′s self-rating depression scale (SDS) before and after treatment of linaclotide group and polyethyetylene glycol group were recorded and compared. Multivariate logistic regression analysis was performed to analyze the factors affected linaclotide in the treatment of FDD (including anorectal manometry). Receiver operating characteristic curve (ROC) was used to analyze the predictive value of risk factors on the efficacy of linaclotide in FDD. Independent sample t-test, paired t-test and chi-square test were used for statistical analysis. Results:After treatment, the weekly CSBM frequencies of linaclotide group and polyethylene glycol group were both higher than those before treatment in the same group (3.20±2.03 vs. 2.44±2.09, 3.10±2.26 vs. 2.58±2.06), and the differences were statistically significant ( t=-4.85 and -5.91, both P<0.001). After treatment, PAC-SYM score of stool shape, rectal symptom, abdominal symptom and total score, NRS score, SAS score and SDS score of linaclotide group and polyethylene glycol group were all lower than those before treatment in the same group (1.41±0.96 vs. 1.89±1.13, 0.95±0.49 vs. 1.14±0.46, 0.69±0.57 vs. 1.00±0.58, 0.96±0.43 vs. 1.23±0.40, 1.54±1.11 vs. 2.48±1.24, 43.54±6.26 vs. 45.13±7.30, 42.10±7.95 vs. 43.78±9.15 and 1.36±1.09 vs. 1.88±1.17, 0.83±0.40 vs. 1.10±0.45, 0.81±0.60 vs. 1.01±0.69, 0.91±0.42 vs. 1.21±0.41, 1.90±1.17 vs. 2.23±1.27, 43.55±7.72 vs. 44.61±8.51, 40.00±6.71 vs. 41.18±7.50), and the differences were statistically significant ( t=7.08, 7.73, 7.15, 9.26, 7.66, 7.96, 8.46, 7.26, 7.16, 5.78, 8.37, 6.17, 4.67 and 7.13, all P< 0.001). After treatment, the NRS score of linaclotide group was lower than that of polyethylene glycol group, and the difference was statistically significant ( t=-2.01, P=0.046). The total effective rate of linaclotide group was higher than that of polyethylene glycol group (77.5%, 62/80 vs. 62.5%, 50/80), and the difference was statistically significant ( χ2=4.29, P=0.038). The results of multivariate logistic regression analysis showed that the threshold of initial sensory volume and maximum tolerable volume were independent risk factors for linaclotide treatment of FDD ( OR=0.965, 95% confidence interval 0.936 to 0.995, P=0.022; OR=0.980, 95% confidence interval 0.962 to 0.999, P=0.041). The results of ROC analysis showed that the efficacy of linaclotide was poor in FDD patients with the threshold of initial sensory volume >67.5 mL or maximum tolerable volume > 117.5 mL. The combined predictive value of initial sensory volume and maximum tolerable volume threshold was higher than that of individual prediction, with an area under the curve of 0.722, sensitivity of 79.0% and specificity of 55.6%. Conclusions:Linaclotide can improve CSBM, constipation symptoms, abdominal pain and psychological status of FDD patients. The initial sensory volume threshold and maximum tolerable volume threshold are independent risk factors of the efficacy of linaclotide in FDD treatment and have certain predictive value in efficacy.

Objective:To explore the clinical application value of salivary pepsin test (Peptest) in the diagnosis of gastroesophageal reflux disease (GERD).Methods:From April to October 2022, at the Department of Gastroenterology of the First Affiliated Hospital of Nanjing Medical University, a total of 81 patients with typical reflux and (or) heartburn symptoms for more than 1 month, who were diagnosed with GERD and completed 24-hour esophageal pH impedance monitoring (24 h MII-pH) and high-resolution esophageal manometry were enrolled. Salivary samples were collected after lunch, at the onset of symptoms, and at random time point on the day of intubation, and all patients received standard dose of proton pump inhibitor (PPI) for 2 weeks. The 24 h MII-pH results were taken as the gold standard for diagnosing GERD. The optimal time point of Peptest and the diagnostic value of combination of Peptest and PPI test in GERD diagnosis were analyzed. The 24 h MII-pH negative patients were further divided into Peptest-positive group and Peptest-negative group. The heartbrun scores, gastroesophageal reflux disease questionnaire (GERD-Q), reflux characteristics, and esophageal motility between the 2 groups were compared and to investigate the differential diagnostic value of Peptest in 24 h MII-pH negative patients. Chi-square test and non-parametric test were used for statistical analysis.Results:The results of 24 h MII-pH indicated that 21 patients (25.9%, 21/81) were diagnosed GERD and 60 patients were negative for 24 h MII-pH. The onset of symptoms was the optimal time point for Peptest, with a sensitivity of 80.9%, a specificity of 50.0%, and an accuracy of 58.0%. The specificity and accuracy of Peptest at the onset of symptoms combined with PPI test in GERD diagnosis were higher than those of Peptest at the onset of symptoms alone (75.0% vs. 50.0%, 74.1% vs. 58.0%), and the differences were statistically significant ( χ2=8.00 and 4.65, P=0.005 and 0.031). Among 60 cases of 24 h MII-pH negative patients, 30 were positive for Peptest at the onset of symptoms and 30 were negative for Peptest at the onset of symptoms. The heartburn scores and GERD-Q scores of Peptest-positive group were both higher than those of Peptest-negative group (3.0 (2.0, 3.0) vs. 1.0 (0.0, 2.3), 12.0 (9.8, 13.0) vs. 9.0 (6.0, 11.0) ); the clearance time of acid reflux of Peptest-positive group was longer than that of Peptest-negative group (57.0 s (22.3 s, 88.0 s) vs. 18.3 s (9.6 s, 32.1 s) ); the lower esophageal sphincter resting pressure and integrated relaxation pressure were lower than those of Peptest-negative group (10.40 mmHg (5.75 mmHg, 18.95 mmHg) vs. 21.45 mmHg (10.65 mmHg, 31.70 mmHg), 3.90 mmHg (2.05 mmHg, 5.35 mmHg) vs. 4.90 mmHg (3.76 mmHg, 8.25 mmHg); 1 mmHg=0.133 kPa); the distal mean nocturnal baseline impedance, the distal contractile integral and esophagogastric junction contractile integral were all lower than those of Peptest-negative group ( 1 783 Ω (1 660 Ω, 2 157 Ω) vs. 2 300 Ω(1 805 Ω, 2 370 Ω), 1 416 mmHg·s·cm (919 mmHg·s·cm, 2 176 mmHg·s·cm) vs. 1 858 mmHg·s·cm (1 395 mmHg·s·cm, 2 880 mmHg·s·cm), 27.7 mmHg·cm (19.8 mmHg·cm, 39.5 mmHg·cm) vs. 52.6 mmHg·cm (27.7 mmHg·cm, 74.6 mmHg·cm) ), and the differences were statistically significant ( Z=-4.00, -3.53, -3.31, -2.34, -2.13, -2.75, -2.14 and -2.43; P<0.001, <0.001, =0.001, =0.019, =0.033, =0.006, =0.032 and =0.015). Conclusions:Peptest may be better at diagnosing GERD at the onset of symptoms compared to postprandial, random time points, and the accuracy of diagnosing GERD further improves when combined with PPI test. Peptest at the onset of symptoms may have differential diagnostic value for GERD patients in 24 h MII-pH negative patients.

Background: The laryngopharyngeal symptoms of gastroesophageal reflux disease (GERD) include hoarseness, foreign body sensation, chronic cough, dysphagia, etc. Its pathogenic mechanisms and reflux characteristics may be different from those of GERD patients simply with typical esophageal symptoms. Aims: To explore the clinical characteristics of GERD patients complicated with laryngopharyngeal symptoms. Methods: Fifty-nine patients having a gastroesophageal reflux disease questionnaire (GerdQ) score ≥8 and abnormal reflux identified by 24 h esophageal impedance-pH monitoring were selected from the outpatients at the First Affiliated Hospital of Nanjing Medical University from January 2019 to December 2021. Twenty-nine cases simply with typical esophageal symptoms were allocated into typical symptom group, and 30 cases complicated with laryngopharyngeal symptoms were allocated into laryngopharyngeal reflux (LPR) group. The general information, results of gastroscopy, 24 h esophageal impedance - pH monitoring and esophageal manometry, as well as the efficacy of proton pump inhibitor (PPI) were collected and compared between the two groups. Results: The proportion of esophagitis in GERD patients in typical symptom group was significantly increased than that in LPR group (P<0.05), while the values of mean nocturnal baseline impedance at 7-3 cm above lower esophageal sphincter (LES) were significantly lower (all P<0.05). Compared with typical symptom group, increased frequency of weak acid reflux, prolonged mean acid clearance time, higher LES relaxation rate, lower velocity of peristaltic waves at 11-7 cm above LES, and poor efficacy of PPI treatment were observed in LPR group (all P<0.05). The severity of heartburn was positively correlated with the percentage of total acid exposure time and DeMeester score (all P<0.05); while the severity of foreign body sensation was positively correlated with the frequency of weak acid reflux and mean time of acid clearance (all P<0.05). Conclusions: The esophageal mucosal injury was mild in GERD patients complicated with laryngopharyngeal symptoms. Laryngopharyngeal symptoms are more likely to be associated with the decreased acid clearance capacity due to esophageal body dysmotility. Strengthened acid suppression therapy should be recommended.