Clinical use of mean nocturnal baseline impedance and post-reflux swallow-induced peristaltic wave index for the diagnosis of gastro-esophageal reflux disease.

The clinical diagnosis of gastro-esophageal reflux disease (GERD) is based on the presence of typical esophageal troublesome symptoms. In clinical practice, heartburn relief following a proton pump inhibitor (PPI) trial or endoscopy can confirm a diagnosis of GERD. In cases of diagnostic uncertainty or before anti-reflux interventions, combined impedance-pH monitoring (MII-pH) provides a comprehensive assessment of both physical and chemical properties of the refluxate, allowing to achieve a conclusive diagnosis of GERD. Recently, the Lyon Consensus proposed the use of mean nocturnal baseline impedance (MNBI) and post-reflux swallow-induced peristaltic wave index (PSPW-I) as novel MII-pH metrics to support the diagnosis of GERD. The calculation of MNBI and PSPW-I currently needs to be performed manually, but artificial intelligence systems for the automated analysis of MII-pH tracings are being developed. Several studies demonstrated the increased diagnostic yield MNBI and PSPW-I for the categorization of patients with GERD at both on- and off-PPI MII-pH monitoring. Accordingly, we performed a narrative review on the clinical use and diagnostic yield of MNBI and PSPW-I when the diagnosis of GERD is uncertain. Based on currently available evidence, we strongly support the evaluation of PSPW-I and MNBI as part of the standard assessment of MII-pH tracings for the evaluation of GERD, especially in patients with endoscopy-negative heartburn.

Eosinophilic esophagitis: novel concepts regarding pathogenesis and clinical manifestations.

Eosinophilic esophagitis is a chronic disease whose incidence and prevalence are increasing, based on a genetic-driven interaction between environment and immune system. Several gene loci involved in the development of the disease have been identified. A two-step mechanism has been hypothesized: a thymic stromal lymphopoietin-induced allergic sensitization followed by upregulation of CAPN14-related esophageal-specific pathways. Environment seems to have a larger effect than genetic variants. Factors that could play a role are allergens, drugs, colonizing bacteria and possibly Helicobacter Pylori infection. Acting on these modifiable risk factors may be a tool to prevent the disease. EoE is characterized by a typical eosinophilic infiltrate limited to the esophageal epithelium, supported by a Th2-mediated immune response, found in other atopic conditions. The key of the pathogenesis is the disfunction of the epithelial barrier which allow the interaction between allergens and inflammatory cells. Eosinophilic-predominant inflammation leads to the typical wall remodeling, histologically characterized by epithelial and smooth muscle hyperplasia, lamina propria fibrosis and neo-angiogenesis. These alterations find their clinical expression in the pattern of symptoms: dysphagia, food impaction, chest pain, heartburn.

Diagnostic delay and misdiagnosis in eosinophilic oesophagitis.

BACKGROUND: Eosinophilic oesophagitis (EoE) may lead to severe complications if not promptly recognised. AIMS: To assess the diagnostic delay in patients with EoE and to explore its risk factors. METHODS: EoE patients followed-up at eight clinics were included via retrospective chart review. Diagnostic delay was estimated as the time lapse occurring between the appearance of the first likely symptoms indicative of EoE and the final diagnosis. Patient-dependent and physician-dependent diagnostic delays were assessed. Multivariable regression models were computed. RESULTS: 261 patients with EoE (mean age 34±14 years; M:F ratio=3:1) were included. The median overall diagnostic delay was 36 months (IQR 12-88), while patient- and physician-dependent diagnostic delays were 18 months (IQR 5-49) and 6 months (IQR 1-24). Patient-dependent delay was greater compared to physician-dependent delay (95% CI 5.1-19.3, p<0.001). A previous misdiagnosis was formulated in 109 cases (41.8%; gastro-oesophageal reflux disease in 67 patients, 25.7%). The variables significantly associated with greater overall diagnostic delay were being a non-smoker, >1 episode of food impaction, previous endoscopy with no biopsies, regurgitation, and ≥2 assessing physicians. Being single was significantly associated with lower overall and patient-dependent diagnostic delay. CONCLUSION: EoE is burdened by substantial diagnostic delay, depending on both patient-related and physician-related factors.