Nonceliac gluten sensitivity

An overview of progress in establishing a diagnostic tool for non-celiac gluten sensitivity

INTRODUCTION

Non-Celiac Gluten Sensitivity (NCGS) is a common disorder characterized by symptoms resembling those of irritable bowel syndrome. In recent years there has been progress in the understanding of the pathogenic pathways and data suggest that NCGS has a distinct immunological profile that differs from celiac disease (CeD). This has fostered the search for a specific biomarker of NCGS.

AREAS COVERED

In this review we will firstly update on pioneer NCGS diagnostic tools, particularly the gluten challenge, serum IgG class antigliadin antibodies, and certain histological characteristics seen at the small intestinal biopsy. Then we will examine the most recent research on potential biomarkers of NCGS, specifically focusing on markers of damage to enterocytes, of translocation of bacteria from the gut into the bloodstream, intestinal permeability, and inflammation.

EXPERT OPINION

So far, no specific biomarker of NCGS has been detected. The diagnosis of NCGS still relies on clinical criteria. A gluten challenge may be useful for diagnostic purposes, however a strong nocebo effect limits the efficacy of this procedure. Additional investigation is necessary to identify biomarkers for NCGS, that may be useful to investigate the epidemiology, clinical spectrum, and natural history of this common disorder.

Efficacy and Safety of a Low-FODMAP Diet in Combination with a Gluten-Free Diet for Adult Irritable Bowel Syndrome: A Systematic Review and Meta-Analysis

BACKGROUND

Common gastrointestinal disease irritable bowel syndrome (IBS) is marked by symptoms like changed bowel habits, bloating, and stomach ache. A low-FODMAP combined gluten-free diet (LF-GFD) has been suggested as a possible therapy for IBS symptoms management.

OBJECTIVE

This study sought to investigate whether a LF-GFD would help patients with IBS.

METHODS

Strict inclusion and exclusion criteria from internet databases helped to identify clinical studies evaluating the intervention of LF-GFD in the treatment of IBS patients. Using measurements including the visual analog scale (VAS) for bloating and pain, the IBS symptom severity scale (IBS-SSS), and IBS quality of life (IBS-QoL), the main results evaluated were the efficacy of LF-GFD in reducing IBS symptoms. Furthermore assessed were the psychological impacts of LF-GFD utilizing the self- rating depression scale (SDS) and self- rating anxiety scale (SAS).

RESULTS

A total of 437 patients (221 on LF-GFD diet and 216 on GFD) were involved in 4 randomized controlled trials and 4 cohort studies. The combined results indicated that LF-GFD reduced the VAS bloating ratings (RR = - 0.58, 95%CI - 0.92-0.23, P = 0.0010, I2 = 83%) and the VAS pain scores (RR = - 0.42, 95%CI - 0.66-0.19, P = 0.005, I2 = 58%). In addition, LF-GFD indicated a substantial enhancement in IBS-SSS scores (MD = - 1.42, 95%CI - 2.74-0.10, P = 0.03, I2 = 24%) and IBS-QoL ratings (MD = 3.75, 95%CI 0.98-6.53, P = 0.008, I2 = 33%). Moreover, the LF-GFD group showed a substantial drop in SDS (MD = - 2.56, 95%CI - 3.38-1.74, P < 0.00001, I2 = 65%) and SAS (MD = - 4.30, 95%CI - 6.53-2.24, P < 0.0001, I2 = 0%) scores compared to the GFD group.

CONCLUSION

LF-GFD therapy significantly enhances clinical symptoms and reduces anxiety and depression in individuals diagnosed with irritable bowel syndrome.

Celiac Disease, Gluten Sensitivity, and Diet Management

PURPOSE OF REVIEW

Celiac disease is a common chronic inflammatory condition of the small bowel triggered by gluten in wheat, rye and barley in the diet. Non-celiac gluten sensitivity presents with symptoms similar to celiac disease with the ingestion of gluten or other components of wheat. In this article, we review challenges presented by a gluten free diet for the treatment of both disorders.

RECENT FINDINGS

Wheat is ubiquitous in the diet and medications/products. A registered dietitian is mandatory for patient education on the gluten free diet. Naturally gluten free foods provide a healthy diet for those with celiac disease. Whole grains labelled gluten free, including oats, are encouraged in the diet as refined grains may be deficient in fiber, protein, and micronutrients, particularly folate. Gluten contamination is the most common cause of persistent symptoms in celiac disease though shared equipment of food preparation may not be as large a problem as suspected. Most with celiac disease on a gluten free diet will fully recover and gain weight that poses a problem for those overweight to start. The gluten free diet may have a negative impact on quality of life for both celiac patients and their families. Those with hypervigilance of the gluten free diet and avoidance of dining out have the lowest quality of life. The gluten free diet is currently the only effective treatment for celiac disease. A registered dietitian is needed to educate patients on the complexity of the gluten free diet with a goal of healthy eating, maintaining a healthy weight, and avoiding disordered eating or diet hypervigilance; key to a good quality of life.

Wheat-Related Disorders in Children: A 360-Degree View

Immunological illnesses related to wheat represent an epidemiologically relevant phenomenon at a pediatric age. The term "Wheat-related disorders" involves a spectrum of diseases: celiac disease, IgE-mediated wheat allergy, non-IgE mediated wheat allergy, wheat-related eosinophilic esophagitis, and non-celiac gluten sensitivity. Their pathogenesis is different. At the same time, wheat represents their common point. This article aims to the state-of-the-art and new clinical evidence in pediatric age.

Two randomized crossover multicenter studies investigating gastrointestinal symptoms after bread consumption in individuals with noncoeliac wheat sensitivity: do wheat species and fermentation type matter?

BACKGROUND

Many individuals reduce their bread intake because they believe wheat causes their gastrointestinal (GI) symptoms. Different wheat species and processing methods may affect these responses.

OBJECTIVES

We investigated the effects of 6 different bread types (prepared from 3 wheat species and 2 fermentation conditions) on GI symptoms in individuals with self-reported noncoeliac wheat sensitivity (NCWS).

METHODS

Two parallel, randomized, double-blind, crossover, multicenter studies were conducted. NCWS individuals, in whom coeliac disease and wheat allergy were ruled out, received 5 slices of yeast fermented (YF) (study A, n = 20) or sourdough fermented (SF) (study B, n = 20) bread made of bread wheat, spelt, or emmer in a randomized order on 3 separate test days. Each test day was preceded by a run-in period of 3 d of a symptom-free diet and separated by a wash-out period of ≥7 d. GI symptoms were evaluated by change in symptom score (test day minus average of the 3-d run-in period) on a 0-100 mm visual analogue scale (ΔVAS), comparing medians using the Friedman test. Responders were defined as an increase in ΔVAS of ≥15 mm for overall GI symptoms, abdominal discomfort, abdominal pain, bloating, and/or flatulence.

RESULTS

GI symptoms did not differ significantly between breads of different grains [YF bread wheat median ΔVAS 10.4 mm (IQR 0.0-17.8 mm), spelt 4.9 mm (-7.6 to 9.4 mm), emmer 11.0 mm (0.0-21.3 mm), P = 0.267; SF bread wheat 10.5 mm (-3.1 to 31.5 mm), spelt 11.3 mm (0.0-15.3 mm), emmer 4.0 mm (-2.9 to 9.3 mm), P = 0.144]. The number of responders was also comparable for both YF (6 to wheat, 5 to spelt, and 7 to emmer, P = 0.761) and SF breads (9 to wheat, 7 to spelt, and 8 to emmer, P = 0.761).

CONCLUSIONS

The majority of NCWS individuals experienced some GI symptoms for ≥1 of the breads, but on a group level, no differences were found between different grains for either YF or SF breads.

CLINICAL TRIAL REGISTRY

clinicaltrials.gov, NCT04084470 (https://classic.

CLINICALTRIALS

gov/ct2/show/NCT04084470).

Nonallergic Diseases Associated With Foods

Clinicians are faced with evaluating real and alleged reactions to foods that may be allergic or nonallergic. Pathogenesis, diagnosis, and treatment of various non-IgE-mediated diseases are discussed in this review. These food-related conditions range from mild to severe. Referral for an allergy workup may be pursued despite the lack of IgE-mediated symptoms. Diagnostic testing is available for defined non-IgE-mediated food diseases that are either immunologic or nonimmunologic. These include celiac disease and related disorders, carbohydrate maldigestion, pancreatic insufficiency, and histamine intolerance. In contrast, there is a paucity of definitive studies to prove food intolerance diseases. There are no definitive diagnostic criteria or testing for nonceliac gluten sensitivity. Functional gastrointestinal disorders, such as irritable bowel syndrome, are better stratified diagnostically but still lack reliable testing. Both nonceliac gluten sensitivity and irritable bowel syndrome are linked to dietary triggers including fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. Therefore, dietary alteration alone may be diagnostic and therapeutic when all other conditions are ruled out. These conditions are important considerations when evaluating a patient with history of a food reaction. There is little evidence that foods are causative in other ailments such as acne, migraines, and nasal congestion and hypersecretion.

Food intolerances

ABSTRACT

Food intolerances are prevalent and often confused with food allergies. This article reviews the complex landscape of adverse reactions to food, distinguishing between immune-mediated responses (food allergies) and nonimmune reactions (food intolerances). It also explores specific food intolerances such as lactose intolerance, nonceliac gluten sensitivity, fructose intolerance, and salicylate sensitivity.