Management of celiac disease in daily clinical practice

Past, Present, and Future of Noninvasive Tests to Assess Gluten Exposure, Celiac Disease Activity, and End-Organ Damage

Although many biomarkers have been proposed, and several are in widespread clinical use, there is no single readout or combination of readouts that correlates tightly with gluten exposure, disease activity, or end-organ damage in treated patients with celiac disease. Challenges to developing and evaluating better biomarkers include significant interindividual variability-related to immune amplification of gluten exposure and how effects of immune activation are manifest. Furthermore, the current "gold standard" for assessment of end-organ damage, small intestinal biopsy, is itself highly imperfect, such that a marker that is a better reflection of the "ground truth" may indeed appear to perform poorly. The goal of this review was to analyze past and present efforts to establish robust noninvasive tools for monitoring treated patients with celiac disease and to highlight emerging tools that may prove to be useful in clinical practice.

Epidemiology of Celiac Disease in Western Iran during 2019-2021

Celiac disease is a growing global public health concern. This epidemiological study is aimed at determining the prevalence of celiac disease in Kermanshah, Western Iran, from 2019 to 2021, as well as the frequency of gastrointestinal and nongastrointestinal manifestations associated with the disease. In this cross-sectional study, the medical records of all patients with a confirmed diagnosis of celiac disease between 2019 and 2021 were reviewed. The average population during the study period was 2,058,545. A researcher-developed checklist was used as the data collection tool, and descriptive statistics were employed for data analysis. During the study period, there were 113 patients diagnosed with celiac disease, with a mean age of 29.1 ± 16.6 years. The three-year prevalence of celiac disease was 5.49 (95% CI: 5.17-5.82) per 100,000 population. Among these patients, 70% (n = 78) was female. The most common gastrointestinal manifestations of the disease were abdominal pain (77.8%), constipation (59.3%), and diarrhea (54.9%). Iron-deficiency anemia (64.6%) and vitamin D3 deficiency (46.1%) were the most common nongastrointestinal manifestations. Growth retardation was observed in 39.0% of patients. This study demonstrated a higher prevalence of celiac disease in Kermanshah compared to global statistics. Given the association of celiac disease with other conditions such as diabetes, irritable bowel syndrome, growth retardation, and iron-deficiency anemia, healthcare providers should consider screening patients for celiac disease. Furthermore, community-based education is crucial in raising awareness about the significance of adhering to a proper diet and reducing wheat consumption.

Guidelines for best practices in monitoring established coeliac disease in adult patients

Coeliac disease (CeD) is an immunological disease triggered by the consumption of gluten contained in food in individuals with a genetic predisposition. Diagnosis is based on the presence of small bowel mucosal atrophy and circulating autoantibodies (anti-type 2 transglutaminase antibodies). After diagnosis, patients follow a strict, life-long gluten-free diet. Although the criteria for diagnosis of this disease are well defined, the monitoring phase has been studied less and there is a lack of specific guidelines for this phase. To develop a set of clinical guidelines for CeD monitoring, we followed the Grading of Recommendations Assessment, Development and Evaluation methodology. Statements and recommendations with the level of evidence were developed and approved by the working group, which comprised gastroenterologists, pathologists, dieticians and biostatisticians. The proposed guidelines, endorsed by the North American and European coeliac disease scientific societies, make recommendations for best practices in monitoring patients with CeD based on the available evidence. The evidence level is low for many topics, suggesting that further research in specific aspects of CeD would be valuable. In conclusion, the present guidelines support clinicians in improving CeD treatment and follow-up and highlight novel issues that should be considered in future studies.

Could Celiac Disease and Overweight/Obesity Coexist in School-Aged Children and Adolescents? A Systematic Review

Background: Celiac disease (CD) is a multifactorial, immune-mediated enteropathic disorder that may occur at any age with heterogeneous clinical presentation. In the last years, unusual manifestations have become very frequent, and currently, it is not so uncommon to diagnose CD in subjects with overweight or obesity, especially in adults; however, little is known in the pediatric population. This systematic review aims to evaluate the literature regarding the association between CD and overweight/obesity in school-age children. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. An electronic database search of articles published in the last 20 years in English was carried out in Web of Sciences, PubMed, and Medline. The quality of the included studies was assessed by using the STrengthening the Reporting of OBservational studies in Epidemiology statement. Results: Of the 1396 articles identified, 9 articles, investigating overweight/obesity in children/adolescents affected by CD or screening CD in children/adolescents with overweight/obesity, met the inclusion criteria. Overall, the results showed that the prevalence of overweight or obesity in school-age children (6-17 years) affected by CD ranged between 3.5% and 20%, highlighting that the coexistence of CD with overweight/obesity in children is not uncommon as previously thought. Conclusion: Although CD has been historically correlated with being underweight due to malabsorption, it should be evaluated also in children with overweight and obesity, especially those who have a familiar predisposition to other autoimmune diseases and/or manifest unusual symptoms of CD.

Adherence to a gluten-free diet in celiac disease patients from Paraguay

INTRODUCTION AND AIM

The treatment for celiac disease is a gluten-free diet that should be strictly and permanently carried out. Our aims were to determine adherence to the gluten-free diet and the risk factors for non-adherence.

MATERIALS AND METHODS

An observational, cross-sectional, comparative study was conducted. It included individuals of both sexes and of any age that presented with celiac disease, lived in Paraguay from January to April 2021, and agreed to participate in the survey. Incomplete questionnaires were excluded. Non-probabilistic convenience sampling was utilized. Adherence was measured using the Leffler questionnaire. The study was approved by the Ethics Committee of the Universidad Privada del Este.

RESULTS

The sample consisted of 371 respondents, 322 (87%) of whom were adults, with a mean age of 38 ± 12 years, and 49 (13%) of whom were children and adolescents, with a mean age of 10 ± 5 years. Female sex was predominant (85%). Adherence to the gluten-free diet was detected in 59% of the adults and 73% of the children and adolescents. The factors significantly associated with adherence included belonging to the child and adolescent age group and having had the diagnosis for a longer time: 9 ± 8 years for the adherence group and 7 ± 8 years for the non-adherence group.

CONCLUSIONS

The present study demonstrated the frequency of adherence to the gluten-free diet in celiac patients in Paraguay. Psychologic and nutritional support is recommended for individuals with celiac disease that do not adhere to their treatment.

Celiac disease and risk of neuropsychiatric disorders: A nationwide cohort study

INTRODUCTION

Previous studies have indicated that patients with celiac disease (CD) may have an increased risk of developing neuropsychiatric disorders. However, large-scale epidemiologic studies on the topic are still scarce. We aimed to examine the association between CD and development of neuropsychiatric disorders during an 18-year follow-up period.

METHODS

We conducted a prospective cohort study. All Danish patients with an incident diagnosis of CD (ICD-10 K90.0) from 2000 to 2018 were identified in nationwide registries and compared with birthdate- and sex-matched controls (variable 1:10 ratio) for the development of a neuropsychiatric disease. Individual neuropsychiatric diseases were also examined. The absolute risk was calculated by the cumulative incidence, and the relative risk was estimated in Cox regression models.

RESULTS

We identified a cohort of 6329 patients with CD diagnosed from 2000 to 2018 and 63,287 matches at risk for developing incident neuropsychiatric disorders. The cumulative incidence of development of any neuropsychiatric disorder was 3.9%, 14.9%, 24.8%, 35.9% after 1, 5, 10, and 15 years of follow-up, respectively, in patients with CD compared with 1.8%, 9.3%, 18.3%, and 27.0% in controls. Gray's test for equality p < 0.001. The relative risk was HR = 1.58 (95% confidence interval: 1.49-1.68) in CD patients compared with matches. For the individual outcomes, CD was associated with an increased relative risk of developing anxiety, depression, eating disorders, epilepsy, migraine, and stress. We also found indications of an increased relative risk of ADHD, alcoholism, bipolar disorders, and drug abuse, although the associations were less clear. No associations were found between CD and dementia, Parkinson's disease, and schizophrenia.

CONCLUSIONS

In this nationwide study including more than 6000 patients with CD, we found an increased risk of development of a neuropsychiatric disorder compared with age- and sex-matched controls. The causes and the clinical relevance of these associations remain to be elucidated.

Potentially Health-Promoting Spaghetti-Type Pastas Based on Doubly Modified Corn Starch: Starch Oxidation via Wet Chemistry Followed by Organocatalytic Butyrylation Using Reactive Extrusion

Extruded spaghetti-type pasta systems were obtained separately either from native or oxidized starch prepared via wet chemistry with the aim of evaluating the effect of oxidation modification of starch. In addition to this, the butyrylation reaction (butyrate (Bu) esterification-short-chain fatty acid) using native or oxidized starch was analyzed under reactive extrusion (REx) conditions with and without the addition of a green food-grade organocatalyst (l(+)-tartaric acid) with the purpose of developing potentially health-promoting spaghetti-type pasta systems in terms of increasing its resistant starch (RS) values. These would be due to obtaining organocatalytic butyrylated starch or not, or the manufacture of a doubly modified starch (oxidized-butyrylated-starch oxidation followed by organocatalytic butyrylation) or not. To this end, six pasta systems were developed and characterized by solid-state ¹³C cross-polarization magic angle spinning nuclear magnetic resonance (CP MAS NMR) spectroscopy, degree of substitution (DS), attenuated total reflectance Fourier transform infrared (ATR/FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), pancreatic digestion, free Bu content analysis and in vitro starch digestibility. The results obtained here suggest that starch oxidation hydrolytically degrades starch chains, making them more susceptible to enzymatic degradation by α-amylase. However, the oxidized starch-based pasta systems, once esterified by Bu mainly on the amylose molecules (doubly modified pasta systems) increased their RS values, and this was more pronounced with the addition of the organocatalyst (maximum RS value = ~8%). Interestingly, despite the checked chemical changes that took place on the molecular structure of starch upon butyrylation or oxidation reactions in corn starch-based spaghetti-type pasta systems, and their incidence on starch digestibility, the orthorhombic crystalline structure (A-type starch) of starch remained unchanged.

Evaluation of a Single Determination of Gluten Immunogenic Peptides in Urine from Unaware Celiac Patients to Monitor Gluten-Free Diet Adherence

INTRODUCTION AND AIM

Usually, adherence to the gluten-free diet (GFD) in celiac patients is indirectly assessed through serological analysis, questionnaires, or invasive methods such as intestinal biopsy. The detection of gluten immunogenic peptides in urine (urinary gluten immunogenic peptides-uGIP) is a novel technique that directly evaluates the ingestion of gluten. The aim of this study was to evaluate the clinical efficacy of uGIP in the follow-up of celiac disease (CD).

METHODS

From April 2019 to February 2020, CD patients reporting complete adherence to the GFD were prospectively enrolled but were unaware of the reason for the tests. Urinary GIP, the celiac dietary adherence test (CDAT), symptomatic visual analog scales (VAS), and tissue transglutaminase antibodies (tTGA) titres were evaluated. Duodenal histology and capsule endoscopy (CE) were performed when indicated.

RESULTS

A total of 280 patients were enrolled. Thirty-two (11.4%) had a positive uGIP test (uGIP+). uGIP+ patients did not show significant differences in demographic parameters, CDAT, or VAS scores. The tTGA+ titre was not related to the positivity of uGIP (14.4% vs. 10.9% in patients with tTGA+ and tTGA-). Regarding histology, 66.7% of the GIP+ patients had atrophy compared to 32.7% of the GIP patients (p-value 0.01). However, the presence of atrophy did not correlate with tTGA. Mucosal atrophy was detected in 29 (47.5%) out of 61 patients by CE. With this method, no noticeable dependence on uGIP results (24 GIP- vs. 5 GIP+) was observed.

CONCLUSIONS

The single uGIP test was positive in 11% of CD cases referring a correct GFD adherence. Furthermore, uGIP results significantly correlated with the duodenal biopsy, formerly considered the gold standard for assessing CD activity.

Clinical features of type 1 and 2 refractory celiac disease: Results from a large cohort over a decade

OBJECTIVES

Refractory celiac disease (RCeD) is a rare complication of celiac disease (CeD) with a severe prognosis. We describe a cohort of patients with RCeD, their clinical and histological features at diagnosis, after therapy and at lymphoma onset, and the rate and causes of death over a 17-year follow-up.

METHODS

We retrospectively enrolled RCeD-I and RCeD-II patients attending our center between January 2002 and October 2019. Medical data were collected at diagnosis and during monitoring. Response to therapy, changes in RCeD molecular markers, number of hospitalizations, discharge diagnosis, and cause and date of death were evaluated. The control cohort consisted of 1015 responsive CeD patients.

RESULTS

Compared with RCeD-I, RCeD-II more frequently exhibits diarrhea (83 vs 64%), anemia (61 vs 50%), hypoalbuminemia (70 vs 21%), parenteral nutrition need (48 vs 7%), ulcerative jejuno-ileitis (7 vs 39%), and extended small intestinal atrophy (62 vs 21%). One RCeD-I and six RCeD-II patients developed lymphoma. Ten RCeD-II patients died, four from lymphoma progression. Among RCeD-II patients, atrophy extension was the only parameter correlated with hypoalbuminemia and mortality.

CONCLUSIONS

Clinical severity, response to therapy, and mortality differ between RCeD-I and RCeD-II. Atrophy extension, evaluated at capsule endoscopy, was associated with disease severity and mortality.

Small-bowel capsule endoscopy and device-assisted enteroscopy for diagnosis and treatment of small-bowel disorders: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2022

MR1: ESGE recommends small-bowel capsule endoscopy as the first-line examination, before consideration of other endoscopic and radiological diagnostic tests for suspected small-bowel bleeding, given the excellent safety profile of capsule endoscopy, its patient tolerability, and its potential to visualize the entire small-bowel mucosa.Strong recommendation, moderate quality evidence. MR2: ESGE recommends small-bowel capsule endoscopy in patients with overt suspected small-bowel bleeding as soon as possible after the bleeding episode, ideally within 48 hours, to maximize the diagnostic and subsequent therapeutic yield.Strong recommendation, high quality evidence. MR3: ESGE does not recommend routine second-look endoscopy prior to small-bowel capsule endoscopy in patients with suspected small-bowel bleeding or iron-deficiency anemia.Strong recommendation, low quality evidence. MR4: ESGE recommends conservative management in those patients with suspected small-bowel bleeding and high quality negative small-bowel capsule endoscopy.Strong recommendation, moderate quality evidence. MR5: ESGE recommends device-assisted enteroscopy to confirm and possibly treat lesions identified by small-bowel capsule endoscopy.Strong recommendation, high quality evidence. MR6: ESGE recommends the performance of small-bowel capsule endoscopy as a first-line examination in patients with iron-deficiency anemia when small bowel evaluation is indicated.Strong recommendation, high quality evidence. MR7: ESGE recommends small-bowel capsule endoscopy in patients with suspected Crohn's disease and negative ileocolonoscopy findings as the initial diagnostic modality for investigating the small bowel, in the absence of obstructive symptoms or known bowel stenosis.Strong recommendation, high quality evidence. MR8: ESGE recommends, in patients with unremarkable or nondiagnostic findings from dedicated small-bowel cross-sectional imaging, small-bowel capsule endoscopy as a subsequent investigation if deemed likely to influence patient management.Strong recommendation, low quality evidence. MR9: ESGE recommends, in patients with established Crohn's disease, the use of a patency capsule before small-bowel capsule endoscopy to decrease the capsule retention rate.Strong recommendation, moderate quality evidence. MR10: ESGE recommends device-assisted enteroscopy (DAE) as an alternative to surgery for foreign bodies retained in the small bowel requiring retrieval in patients without acute intestinal obstruction.Strong recommendation, moderate quality evidence. MR11: ESGE recommends DAE-endoscopic retrograde cholangiopancreatography (DAE-ERCP) as a first-line endoscopic approach to treat pancreaticobiliary diseases in patients with surgically altered anatomy (except for Billroth II patients).Strong recommendation, moderate quality evidence.

Diagnostic management of patients reporting symptoms after wheat ingestion

Many patients report symptoms after wheat ingestion experiencing a wide spectrum of clinical manifestations. Three possible diagnoses have been recognized: celiac disease (CD), wheat allergy (WA), and non-celiac (gluten) wheat sensitivity (NCGS/NCWS). CD is a chronic immune-mediated disease of the small bowel caused by exposure to dietary gluten in genetically predisposed individuals, with a prevalence of approximately 1%. It is characterized by mucosal inflammation and atrophy following exposure to gluten and improvement after gluten withdrawal. Food allergies are immunological responses to a food antigen. WA is the expression of an immunologically mediated process that can be immunoglobulin E (IgE) or non-IgE mediated; its many symptoms include urticaria/angioedema, asthma, rhinitis, and anaphylaxis. NCGS/NCWS is characterized by gastrointestinal and/or extra-intestinal symptoms after ingestion of gluten-containing food in subjects not affected by CD or WA. The aim of this review is to help physicians and nutritionists diagnose the cause of symptoms reported after wheat ingestion, thus avoiding patient frustration, inappropriate testing, and incorrect or missed diagnoses. An algorithm for the diagnostic approach in these patients is provided, to help to diagnose CD, WA, NCGS/NCWS or to identify possible functional disorders as the wheat-sensitive irritable bowel syndrome. A personalized approach, regular follow-up, and the help of a skilled healthcare professional are mandatory for patients with symptoms following wheat ingestion is provided. A gluten-free-diet is often recommended for patients with self-reported gluten/wheat-dependent symptoms; for patients with symptoms similar to those of functional diseases while there is evidence that a low-FODMAP diet could be the first option.

Study on the Relationship between Unexplained Recurrent Abortion and HLA-DQ Gene Polymorphism

Objective

The study aimed to investigate the relationship between human leukocyte antigen (HLA-DQB1) gene variants and recurrent miscarriage.

Methods

HLA-DQ gene polymorphisms (PCR-SSP) were detected in 50 couples with recurrent miscarriage (URSA group) and 30 couples with normal births (control group) using sequence-specific primer-guided polymerase chain reaction.

Results

The frequency of the DQB1 ∗ 0303 allele in the URSA group (21.50%) was substantially higher than that of the control group (11.67%) (P=0.0260 0.05, RR = 1.754); however, the frequency of the DQB1 ∗ 0302 allele in the URSA group (4.00%) was substantially lower than that of the control pair (10.00%) (P=0.0318 0.05, RR = 0.400); the frequency of sharing one allele was 46.00% (23/50) in the URSA group and 0.00% (0/30) in the normal control group; the frequency of sharing two alleles was 40.00% (2/50) in the URSA group and 43.33% (13/30) in the normal control group, with no significant difference between the two groups.

Conclusion

For the Zhejiang population, HLA-DQB1 ∗ 0303 may be a susceptibility gene for recurrent miscarriage, while HLA-DQB1 ∗ 0302 may be protective against recurrent miscarriage, especially for women.

Pathophysiology and therapeutic management of anemia in gastrointestinal disorders

INTRODUCTION

Anemia is a common complication of gastrointestinal (GI) disorders, with a prevalence up to 60% in celiac disease (CeD) and inflammatory bowel disease (IBD). Iron deficiency anemia (IDA) is the most prevalent form of anemia in these conditions, but chronic inflammation and vitamin B12 deficiency represent other common contributing mechanisms, especially in IBD.

AREAS COVERED

We discuss the pathogenesis of anemia in various medical GI disorders, the sometime problematic distinction between IDA, anemia of inflammation (AI) and the association of the two, and therapeutic and preventive measures that can be useful for the management of anemia in GI disorders. Unfortunately, with the exception of IDA and AI in IBD, large RCT concerning the treatment of anemia in GI disorders are lacking.

EXPERT OPINION

Anemia management strategies in GI disorders are outlined, with a focus on the main prevention, diagnostic, and therapeutic measures. Specific problems and situations such as the role of gluten-free diet for IDA treatment in CeD, the choice between oral and parenteral supplementation of iron or vitamin B12 in carential anemias, the use of endoscopic procedures to stop bleeding in intestinal angiodysplasia and preventive/treatment strategies for NSAID-associated GI bleeding are discussed.

Evaluation of Celiac Disease by Minimally Invasive Biomarkers in a Spanish Pediatric Population

Background: The diagnosis of celiac disease (CD) has been substantially improved with the availability of highly sensitive CD-specific IgA-TG2, Ig-GDP, and IgA-EMA. The European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) published (2012) and updated (2020) diagnostic criteria for CD in order to simplify CD diagnosis and to avoid biopsies in selected patients. Methods: A prospective study including 5641 pediatric patients (0–16 years old) from January 2012 to January 2019 was performed. CD diagnosis was made according to the ESPGHAN algorithm. The objective of this study was to evaluate the utility of biomarkers and the relationship between TGA-IgA and EMA titers. Results: CD diagnoses were confirmed in 113 patients, 110 were IgA-TG2-positive and 3 (2.7%) had IgA deficiency. The diagnosis was made by serologic tests in 95 (84.1%) patients. Only 18 (15.9%) patients underwent intestinal biopsy. We obtained 100% concordance between IgA-EMA and positive results for IgA-TG2 ≥ 10 ULN with IgA-EMA antibody titer ≥ 1:80. Conclusions: This study provides evidence of a positive correlation between IgA-TG2 antibody serum levels and IgA-EMA. The diagnosis could be guaranteed with strict application of IgA-TG2 values ≥ 10 ULN (confirmed by subsequent testing) plus the serological response to the gluten-free diet (GFD).

Effectiveness of Capsule Endoscopy and Double-Balloon Enteroscopy in Suspected Complicated Celiac Disease

BACKGROUND & AIMS

Complicated celiac disease (CCD) is a rare but severe condition with a poor prognosis. Guidelines recommend use of capsule endoscopy (CE) to explore the small bowel (SB), followed by a double-balloon enteroscopy (DBE) in selected cases with suspected CCD. Our study aimed to evaluate the diagnostic yield (DY) of CE and DBE in identifying and monitoring CCD.

METHODS

Consecutive suspected CCD patients were enrolled prospectively to undergo CE and/or DBE in the presence of: persistent symptoms despite a correct gluten-free diet (GFD), increased anti-transglutaminase antibodies titer, lack of adherence to the GFD, and CCD monitoring. The DY of CE and DBE were calculated. The incidence of neoplastic complications and mortality were assessed.

RESULTS

In total, 130 patients (97 women; age, 49 ± 16 y) underwent 151 CEs and 23 DBEs. The DY of CE was 46%. Patients older than age 50 years (at CE examination or at CD diagnosis) with a CD duration shorter than 5 years were at higher risk of positive CE (relative risk, 1.6 and 1.7 in case of enrollement or CD diagnosis after 50 years of age, and 1.5 in case of short CD duration; P < .05) than their counterparts. Up to 40% of SB lesions were unreachable by upper endoscopy. At the end of the diagnostic work-up, 25 patients with premalignant/malignant lesions were identified: 12 type 1 refractory CD (RCD-1), 7 type 2 RCD (RCD-2), and 6 enteropathy-associated T-cell lymphoma (EATL). Six patients died: 2 patients with RCD-2 and 4 patients with EATL.

CONCLUSIONS

In case of suspected CCD, CE should be the first-line approach to detect complications and to identify patients deserving DBE. Older and symptomatic patients with suspected CCD deserve a careful evaluation of the SB, especially during the first years after diagnosis.

Maintaining, Managing, and Tele-Monitoring a Nutritionally Adequate Mediterranean Gluten-Free Diet and Proper Lifestyle in Adult Patients

The gluten-free diet (GFD) is a restrictive diet. In many cases, it must be permanent and strict, and it may be associated with both nutritional deficiencies and excesses, which can be prevented by following a healthy, natural Mediterranean GFD (Med-GFD). In this paper, we describe the importance of the Mediterranean diet, the correct intake of vitamins and minerals, and how they may play an important protective role against chronic or degenerative conditions. Herewith, we analyze different aspects that influence the ability to maintain a correct and balanced Med-GFD, which may contribute to the health status of patients, including a conscious use of gluten-free products to maintain a healthy lifestyle. Monitoring the Med-GFD remains a pivotal issue: to evaluate the presence of gluten peptides in urine, it could be important to introduce point-of-care testing, an efficient method for GFD self-monitoring (immunochromatographic technique), together with online nutritional questionnaires. Indeed, medical care via telemedicine can provide practical indications aimed at supporting patients and doctors. A natural Med-GFD can ensure the correct intake of nutrients and could be important for patients affected by gluten-related disorders, helping them to maintain a correct and healthy lifestyle.

Celiac disease: From genetics to epigenetics

Celiac disease (CeD) is a multifactorial autoimmune disorder spread worldwide. The exposure to gluten, a protein found in cereals like wheat, barley and rye, is the main environmental factor involved in its pathogenesis. Even if the genetic predisposition represented by HLA-DQ2 or HLA-DQ8 haplotypes is widely recognised as mandatory for CeD development, it is not enough to explain the total predisposition for the disease. Furthermore, the onset of CeD comprehend a wide spectrum of symptoms, that often leads to a delay in CeD diagnosis. To overcome this deficiency and help detecting people with increased risk for CeD, also clarifying CeD traits linked to disease familiarity, different studies have tried to make light on other predisposing elements. These were in many cases genetic variants shared with other autoimmune diseases. Since inherited traits can be regulated by epigenetic modifications, also induced by environmental factors, the most recent studies focused on the potential involvement of epigenetics in CeD. Epigenetic factors can in fact modulate gene expression with many mechanisms, generating more or less stable changes in gene expression without affecting the DNA sequence. Here we analyze the different epigenetic modifications in CeD, in particular DNA methylation, histone modifications, non-coding RNAs and RNA methylation. Special attention is dedicated to the additional predispositions to CeD, the involvement of epigenetics in developing CeD complications, the pathogenic pathways modulated by epigenetic factors such as microRNAs and the potential use of epigenetic profiling as biomarker to discriminate different classes of patients.

Anti-SARS-CoV-2 immunoglobulin profile in patients with celiac disease living in a high incidence area

BACKGROUND AND AIM

How symptoms and antibodies related to SARS-CoV-2 infection develop in patients with celiac disease (CD) is unclear. We aimed to investigate the impact of SARS-CoV-2 infection in CD patients.

METHODS

CD patients were interviewed about the development of COVID-19 symptoms, compliance with anti-virus measures and adherence to a gluten-free diet (GFD). The presence of anti-SARS-CoV-2 IgG and IgA (anti-RBD and N proteins) was compared to that in non-CD subjects. Expression of the duodenal ACE2 receptor was investigated. When available, data on duodenal histology, anti-tissue transglutaminase IgA (tTGA), comorbidities and GFD adherence were analyzed.

RESULTS

Of 362 CD patients, 42 (12%) reported COVID-19 symptoms and 21% of these symptomatic patients presented anti-SARS-CoV-2 Ig. Overall, 18% of CD patients showed anti-SARS-CoV-2 Ig versus 25% of controls (p = 0.18). CD patients had significantly lower levels of anti-N IgA. tTGA, duodenal atrophy, GFD adherence or other comorbidities did not influence symptoms and/or antibodies. The ACE2 receptor was detected in the non-atrophic duodenal mucosa of patients; atrophy was associated with lower expression of the ACE2 receptor.

CONCLUSION

CD patients have an anti-SARS-CoV-2 Ig profile similar to non-celiac controls, except for anti-N IgA. No risk factors were identified among CD parameters and GFD adherence.

Determination of gluten immunogenic peptides for the management of the treatment adherence of celiac disease: A systematic review

BACKGROUND

Gluten is a complex mixture of proteins with immunogenic peptide sequences triggering the autoimmune activity in patients with celiac disease (CeD). Gluten immunogenic peptides (GIP) are resistant to gastrointestinal digestion and are then excreted via the stool and urine. Most common detection methods applied in the follow-up visits for CeD patients such as serology tests, dietetic interviews, questionnaires, and duodenal biopsy have been proved to be inefficient, invasive, or inaccurate for evaluating gluten-free diet (GFD) compliance. Determination of excreted GIP in stool and urine has been developed as a non-invasive, direct, and specific test for GFD monitoring.

AIM

To summarize published literature about the clinical utility of GIP determination in comparison to the tools employed for GFD monitoring.

METHODS

PubMed and Web of Science searches were performed using the keywords “gluten immunogenic peptides” or “gluten immunogenic peptide” and a combination of the previous terms with “feces”, “stools”, “urine”, “celiac disease”, “gluten-free diet”, and “adherence” to identify relevant clinical studies published in English and Spanish between 2012 to January 2021. Reference lists from the articles were reviewed to identify additional pertinent articles. Published articles and abstracts reporting the clinical use of GIP determination in stool and/or urine for the follow-up of patients with CeD in comparison with other tools in use were included. Case reports, commentaries, reviews, conference papers, letters, and publications that did not focus on the aims of this review were excluded.

RESULTS

Total of 15 publications were found that involved the use of GIP determination in stool and/or urine to monitor the adherence to the GFD in comparison to other tools. Studies included both children and adults diagnosed with CeD and healthy volunteers. Overall, these preliminary studies indicated that this novel technique was highly sensitive for the detection of GFD transgressions and therefore could facilitate the follow-up of patients with CeD. Tools identified in this work included the CeD-specific serology, dietetic questionnaires, symptomatology, and the duodenal biopsy. Review of the literature revealed that the rates of GFD adherence may vary between 30%-93% using either stool or urine GIP determination, 49%-96% by the serology, 59%-94% using the dietetic questionnaires, 56%-95% by the reported symptoms and 44%-76% with the duodenal biopsy. In addition, the association between the different methods and histological abnormalities (Marsh II-III) was found to be 33%-100% for GIP determination (stool and urine), 25%-39% for CeD-specific serology, 3%-50% for dietetic questionnaires, and 22%-28% for the symptomatology.

CONCLUSION

Excreted GIP detection is the precise approach for determining voluntary or involuntary gluten consumption in CeD patients preventing future complications arising from gluten exposure.

Effects of coronavirus disease 2019 on the digestive system and its nutritional implications

PURPOSE OF REVIEW

There has been a deluge of scientific data since coronavirus disease 2019 (COVID-19) was first reported. The effects of COVID-19 on the digestive system are now increasingly well understood. This article aims to review the current data on the effects of COVID-19 on the digestive system with particular emphasis on preexisting digestive diseases and its implications on nutrition practices.

RECENT FINDINGS

Evidence has shown that Severe acute respiratory syndrome coronavirus 2 virus affects the gastrointestinal (GI) tract, pancreas and hepatobiliary system resulting in different GI manifestations. Several preexisting digestive diseases have been investigated. These studies have revealed that these special patient population groups are generally not at an increased risk to contract COVID-19, but are susceptible to develop increasing severity of disease. Aside from medical therapy, optimizing nutritional care has a beneficial role in this group of patients.

SUMMARY

GI manifestations of COVID-19 in addition to preexisting digestive diseases have an impact on patient's nutrition. Digestion, absorption and transport of nutrients may be impaired. To date, there are no existing guidelines on the nutritional management of patients for this particular at-risk group. Most nutrition practices are based only on observations and clinical experience. Basic prepandemic nutrition care principles are primarily followed but often individualized based on clinical judgment.

Clinical Value of Tissue Transglutaminase Antibodies in Celiac Patients over a Long Term Follow-Up

Introduction & Aim: Anti-tissue transglutaminase antibody (tTGA) titer is used during the follow-up of celiac patients to evaluate gluten-free diet (GFD) responsiveness. However, no clear data are available on this issue. The aim of this study was to evaluate tTGA significance during celiac disease (CD) monitoring. Methods: From January 2017 to January 2020, consecutive CD patients on a GFD with persistent positive tTGA were enrolled. Antibody titres were evaluated on a yearly basis from CD diagnosis to the last follow-up. Urinary gluten detection tests, duodenal histology and capsule enteroscopy (CE) were performed. A tTGA-positive cohort was compared with a control group composed of 212 treated CD patients with negative tTGA. Results: 65 patients (12% males, median age at enrollment and CD diagnosis, 37 (14–86) and 31 (1–76), respectively, median follow up 4 (1–26) years) presented with positive tTGA during follow-up. Overall, the tTGA titres were 3 (1–79) fold increased (ULN). Three different tTGA trends were recognized: (I) 36 (55%) patients with a progressive titres decrease; (II) 16 (25%) patients with a fluctuating behavior; (III) 13 (20%) patients with a steady state or increased titres. tTGA+ patients did not present with different clinical and demographic parameters. Duodenal atrophy was present in 10% vs. 36% of the tTGA positive vs. negative group (p < 0.005), respectively. Gluten detection results were positive in 3 (8%) cases, all in the III group. In tTGA+ patients, CE did not identify any CD-related complications. Conclusions: tTGA positivity during CD follow up did not present a relevant clinical significance without association with autoimmune comorbidities and mucosal damage.

Dynamics and Considerations in the Determination of the Excretion of Gluten Immunogenic Peptides in Urine: Individual Variability at Low Gluten Intake

BACKGROUND

A lifelong strict gluten-free diet is the only available treatment for celiac disease, but total exclusion of gluten is difficult to achieve. The aim of this study was to determine the range of time and the amount of gluten immunogenic peptides (GIP) excreted in urine after specific gluten ingestions.

METHODS

20 healthy participants followed the same diet for 12 days in which 50 mg and 2 g of gluten were ingested and all the urinations were collected. GIP were analyzed by lateral flow immunoassay (LFIA) tests and quantified using an LFIA reader.

RESULTS

GIP were detected in 15% and 95% of participants after 50 mg and 2 g gluten intakes, respectively. The higher frequency and concentration of GIP was found between 6 and 9 h after both gluten ingestions. The ranges of detection were 3-12 h (50 mg) and 0-15 h (2 g).

CONCLUSIONS

An increase in the frequency of urine tests may be a suitable approach to avoid false negative results. The use of the LFIA test in three urine samples collected at different times may show a sensitivity of 19.6% for a gluten ingestion like 50 mg, increasing to 93% after 2 g consumption.

Guidelines on Standard and Therapeutic Diets for Adults in Hospitals by the French Association of Nutritionist Dieticians (AFDN) and the French Speaking Society of Clinical Nutrition and Metabolism (SFNCM)

AIM

Hospital food provision is subject to multiple constraints (meal production, organization, health safety, environmental respect) which influence the meal tray offered to the patient. Multiple diets can add complexity and contribute to non-consumption of the meal. To avoid undernutrition, it appeared necessary to propose guidelines for foods and diets in hospitals.

METHODS

These guidelines were developed using the Delphi method, as recommended by the HAS (French Health Authority), based on a formal consensus of experts and led by a group of practitioners and dieticians from the AFDN (French Association of Nutritionist Dieticians) and SFNCM (French Society of Clinical Nutrition and Metabolism).

RESULTS

Twenty-three recommendations were deemed appropriate and validated by a panel of 50 national experts, following three rounds of consultations, modifications and final strong agreement. These recommendations aim to define in adults: 1-harmonized vocabulary related to food and diets in hospitals; 2-quantitative and qualitative food propositions; 3-nutritional prescriptions; 4-diet patterns and patient adaptations; 5-streamlining of restrictions to reduce unnecessary diets and without scientific evidence; 6-emphasizing the place of an enriched and adapted diet for at-risk and malnourished patients.

CONCLUSION

These guidelines will enable catering services and health-care teams to rationalize hospital food and therapeutic food prescriptions in order to focus on individual needs and tasty foods. All efforts should be made to create meals that follow these recommendations while promoting the taste quality of the dishes and their presentation such that the patient rediscovers the pleasure of eating in the hospital.

Acquired Refractory Iron Deficiency Anemia

Anemia is a global health problem affecting one-third of the world population, and half of the cases are due to iron deficiency (ID). Iron deficiency anemia (IDA) is the leading cause of disability in several countries. Although multiple mechanisms may coexist, ID and IDA causes can be classified as i) insufficient iron intake for the body requirement, ii) reduced absorption, and iii) blood losses. Oral iron represents the mainstay of IDA treatment. IDA is defined as "refractory" when the hematologic response after 4 to 6 weeks of treatment with oral iron (an increase of >=1 g/dL of Hb) is absent. The cause of iron-refractory anemia is usually acquired and frequently related to gastrointestinal pathologies, although a rare genetic form called iron-refractory iron deficiency anemia (IRIDA) exists. In some pathological circumstances, either genetic or acquired, hepcidin increases, limiting the absorption in the gut, remobilization, and recycling of iron, thereby reducing iron plasma levels. Indeed, conditions with high hepcidin levels are often under-recognized as iron refractory, leading to inappropriate and unsuccessful treatments. This review provides an overview of the iron refractory anemia underlying conditions, from gastrointestinal pathologies to hepcidin dysregulation and iatrogenic or provoked conditions, and the specific diagnostic and treatment approach.

Adherence to dietary treatment and clinical factors associated with anti-transglutaminase antibodies in celiac disease during the follow-up

INTRODUCTION

In clinical practice, celiac disease (CD) is monitored through anti-transglutaminase (TGA-IgA) antibody levels. The normalization of serum levels in successive periodic measurements indicates good response and adherence to dietary treatment.

OBJECTIVES

To evaluate the factors associated with the evolution of TGA-IgA antibodies and their association with dietary non-compliance and diseases related to CD.

METHODS

This prospective observational study was carried out in 254 participants, who were recruited from patients from a hospital in southern Spain. Information about sex, age, serological test results, HLA DQ2/DQ8 haplotypes, mucosal atrophy, gastrointestinal and extra-intestinal symptoms, as well as diagnosis of diseases related to CD, was collected.

RESULTS

Clinical manifestations, such as diarrhoea, abdominal pain and weight loss, showed differences according to sex and age. Children under 18 years of age presented a degree of total or severe atrophy of the intestinal villi. TGA-IgA antibodies concentrations were directly associated with the number of digestive disorders manifested by the patient and the record of dietary non-compliance and inversely related to the number of extra-digestive disorders.

CONCLUSIONS

Adolescents between 12 and 18 years old were the least monitored as well as the group with more extra-intestinal symptoms reported. Therefore, it is necessary to develop strategies in clinical practice aimed at this population group and continuous monitoring should be implemented to improve life quality and reduce complications that may arise in the long term.

Mediterranean Gluten-Free Diet: Is It a Fair Bet for the Treatment of Gluten-Related Disorders?

Gluten-free diet (GFD) is the current treatment of gluten-related disorders. It eliminates wheat, barley, and rye, while the exclusion of oats is still under debate. GFD is based on a combination of naturally gluten-free foods and gluten-free substitutes of cereal-based foods. Although effective as treatment of gluten-related disorders, today there is concern about how to improve GFD's nutritional quality, to make it not only gluten-free, but also healthy. The "Mediterranean diet" (MedD) refers to the dietary pattern and eating habits typical of populations living in the Mediterranean basin, which have been associated with low prevalence of several diet-related pathologies. Here we present a narrative review of the current knowledge about GFD and MedD, their characteristics and central food components. Based on the Mediterranean diet pyramid developed by the Italian pediatric society, we propose a combination between the MedD and the GFD, an attractive alternative to reach a gluten-free state that at the same time is healthy, with a clear benefit to those who practice it.

How to manage celiac disease and gluten-free diet during the COVID-19 era: proposals from a tertiary referral center in a high-incidence scenario

The outbreak of COVID-19 and SARS-CoV-2 infection is spreading worldwide as the first coronavirus pandemic. The clinical picture is variable but flu-like symptoms are common with bilateral interstitial pneumonia being the most frightening presentation. No specific therapies nor vaccine have been developed to date and the only way to limit the virus diffusion is by modifying one's lifestyle limiting social life and following strict hygienic precautions. No data is available on the risk of COVID-19 and its outcomes in celiac disease (CeD). The restrictions applied to counter COVID-19 can impact on CeD treatment and gluten-free dieting, the only available therapy for CeD. With the present manuscript, we aim to support gastroenterologists and nutritionists in the management of CeD patients in the new pandemic scenario, being conscious that availability and local situations are extremely various.

Beneficial Effects of a Low-Nickel Diet on Relapsing IBS-Like and Extraintestinal Symptoms of Celiac Patients during a Proper Gluten-Free Diet: Nickel Allergic Contact Mucositis in Suspected Non-Responsive Celiac Disease

Background and Aim: Nickel (Ni)-rich foods can induce allergic contact mucositis (ACM) with irritable bowel syndrome (IBS)-like symptoms in predisposed subjects. Ni ACM has a high prevalence (>30%) in the general population and can be diagnosed by a Ni oral mucosa patch test (omPT). Many celiac disease (CD) patients on a gluten-free diet (GFD) often show a recrudescence of gastrointestinal and extraintestinal symptoms, although serological and histological remission has been achieved. Since a GFD often results in higher loads of ingested alimentary Ni (e.g., corn), we hypothesized that it would lead to a consequent intestinal sensitization to Ni in predisposed subjects. We wanted to (1) study Ni ACM prevalence in still symptomatic CD patients on a GFD and (2) study the effects of a low-Ni diet (LNiD) on their recurrent symptoms. Material and Methods: We recruited 102 consecutive CD patients (74 female, 28 male; age range 18–65 years, mean age 42.3 ± 7.4) on a GFD since at least 12 months, in current serological and histological remission (Marsh–Oberhuber type 0–I) who complained of relapsing gastrointestinal and/or extraintestinal symptoms. Inclusion criteria: presence of at least three gastrointestinal symptoms with a score ≥5 on the modified Gastrointestinal Symptom Rating Scale (GSRS) questionnaire. Exclusion criteria: IgE-mediated food allergy; history of past or current cancer; inflammatory bowel diseases; infectious diseases including Helicobacter pylori; lactose intolerance. All patients enrolled underwent Ni omPT and followed a LNiD for 3 months. A 24 symptoms questionnaire (GSRS modified according to the Salerno Experts’ Criteria, with 15 gastrointestinal and 9 extraintestinal symptoms) was administered at T0 (free diet), T1 (GFD, CD remission), T2 (recurrence of symptoms despite GFD), and T3 (GFD + LNiD) for comparisons. Comparisons were performed using Wilcoxon signed-rank test. RESULTS: Twenty patients (all female, age range 23–65 years, mean age 39.1 ± 2.9) out of 102 (19.6%) were finally included. All 20 patients enrolled (100%) showed positive Ni omPT, confirming an Ni ACM diagnosis. A correct GFD (T0 vs. T1) induced the improvement of 19 out of the total 24 (79.2%) symptoms, and 14 out of 24 (58.3%) were statistically significant (p-value < 0.0083 according to Bonferroni correction). Prolonged GFD (T1 vs. T2) revealed the worsening of 20 out of the total 24 (83.3%) symptoms, and 10 out of 24 (41.7%) were statistically significant. LNiD (T2 vs. T3) determined an improvement of 20 out of the total 24 (83.4%) symptoms, and in 10 out of 24 (41.7%) symptoms the improvement was statistically significant. Conclusions: Our data suggest that the recrudescence of gastrointestinal and extraintestinal symptoms observed in CD subjects during GFD may be due to the increase in alimentary Ni intake, once gluten contamination and persisting villous atrophy are excluded. Ni overload can induce Ni ACM, which can be diagnosed by a specific Ni omPT. Improvement of symptoms occurs after a proper LNiD. These encouraging data should be confirmed with larger studies.

Small-bowel capsule endoscopy in patients with celiac disease, axial versus lateral/panoramic view: Results from a prospective randomized trial

BACKGROUND AND AIM

Capsule enteroscopy (CE) is recommended in the management of complicated celiac disease (CD). However, published data are derived from axial-view capsule systems. No data are available on the use of lateral/panoramic view capsules. This study aimed at evaluating the diagnostic yield and efficacy of the lateral/panoramic versus the axial view capsule system in CD.

METHODS

Consecutive CD patients were enrolled in a prospective monocentric study. Each patient ingested an axial (PillCam SB3) and a lateral/panoramic (CapsoCam Plus) view capsule with a 3-h interval in a randomized order. Two experts blindly evaluated the CE carried out. A third expert reviewed the videos in cases of discordance.

RESULTS

Twenty-five CD patients were enrolled (four males, age at CE 51.2 ± 16.6 years, age at CD diagnosis 41.7 ± 20.6, years on a gluten-free diet [GFD] 9.6 ± 9.4). Indications at CE were refractory CD in nine cases, non-responsiveness to GFD in 10 and GFD non-compliance in six. A positive finding was evidenced in 15 (60%) and 13 (52%) cases by CapsoCam and PillCam respectively (not significant). Atrophy was detected by both capsules. Considering the percentage of the small-bowel mucosa presenting atrophy signs, mean values were 22% ± 35 and 20% ± 29 for lateral/panoramic and axial systems, respectively (not significant). Compared to duodenal histology, PillCam correctly identified 80% of patients with SB atrophy, whereas CapsoCam identified 73% of cases.

CONCLUSIONS

Lateral/panoramic view CE is effective in the detection of small-bowel atrophy in CD and presents good sensitivity and specificity when compared to histology.

Safety of occasional ingestion of gluten in patients with celiac disease: a real-life study

BACKGROUND

Gluten-free diet (GFD) decreases the quality of life of celiac disease (CD) patients, who frequently ask to occasionally ingest gluten-containing food. We evaluated CD patients reporting voluntary and occasional transgressions to their GFD.

METHODS

From October 2017 to September 2018, the patients reporting occasional and voluntary gluten ingestion (GFD-noncompliant) were prospectively enrolled. These patients underwent clinical examination, blood tests, duodenal biopsy, capsule enteroscopy (CE), and a validated food-frequency questionnaire (FFQ) assessing the frequency and quantity of gluten intake. Mortality was calculated and compared to the general population. A group of patients on strict GFD (GFD-adherent) acted as controls.

RESULTS

One thousand three hundred seventy-eight CD patients were evaluated during the study period. One hundred nine (8%) reported occasional (weekly or monthly) voluntary ingestion of gluten. The mean gluten intake was 185.2 ± 336.9 g/year, and the duration of their incorrect GFD was 8.6 ± 6.9 years. Among the noncompliant patients, 57% did not present any histological alteration; furthermore, the Marsh score profile was not different between compliant and noncompliant patients. Seventy percent did not present any alteration at CE. Seventy-five percent of patients reported no gastrointestinal symptoms after gluten ingestion. Twenty-three percent of patients in the GFD-noncompliant group presented positive tTG-IgA. No association was found between gluten intake, clinical symptoms, and biomarkers. Mortality was not different between the groups and the general population.

CONCLUSIONS

Our results are that in a real-life scenario, a group of CD patients on long-term gluten intake showed no significant clinical symptoms or small bowel damage, thus suggesting that a degree of tolerance towards gluten consumption can be reached.

Multifactorial Etiology of Anemia in Celiac Disease and Effect of Gluten-Free Diet: A Comprehensive Review

Celiac disease (CD) is a multisystemic disorder with different clinical expressions, from malabsorption with diarrhea, anemia, and nutritional compromise to extraintestinal manifestations. Anemia might be the only clinical expression of the disease, and iron deficiency anemia is considered one of the most frequent extraintestinal clinical manifestations of CD. Therefore, CD should be suspected in the presence of anemia without a known etiology. Assessment of tissue anti-transglutaminase and anti-endomysial antibodies are indicated in these cases and, if positive, digestive endoscopy and intestinal biopsy should be performed. Anemia in CD has a multifactorial pathogenesis and, although it is frequently a consequence of iron deficiency, it can be caused by deficiencies of folate or vitamin B₁₂, or by blood loss or by its association with inflammatory bowel disease (IBD) or other associated diseases. The association between CD and IBD should be considered during anemia treatment in patients with IBD, because the similarity of symptoms could delay the diagnosis. Vitamin B₁₂ deficiency is common in CD and may be responsible for anemia and peripheral myeloneuropathy. Folate deficiency is a well-known cause of anemia in adults, but there is little information in children with CD; it is still unknown if anemia is a symptom of the most typical CD in adult patients either by predisposition due to the fact of age or because biochemical and clinical manifestations take longer to appear.

Diagnostic accuracy of a fully automated multiplex celiac disease antibody panel for serum and plasma

Background

An automated multiplex platform using capillary blood can promote greater throughput and more comprehensive studies in celiac disease (CD). Diagnostic accuracy should be improved using likelihood ratios for the post-test probability of ruling-in disease.

Methods

The Ig_plex™ Celiac Disease Panel on the sqidlite™ automated platform measured IgA and IgG antibodies to tTG and DGP in n = 224 CD serum or plasma samples. Diagnostic accuracy metrics were applied to the combined multiplex test results for several CD populations and compared to conventional single antibody ELISA tests.

Results

With multiple positive antibody results, the post-test probability for ruling-in untreated and treated CD increased to over 90%. The number of samples positive for more than one antibody also increased in untreated CD to ≥90%. Measurement of all four CD antibodies generate cut-off dependent accuracy profiles that can monitor response to treatment with the gluten-free diet (GFD). Higher positive tTG and DGP antibodies are seen more frequently in confirmed CD without (81%–94%) than with GFD treatment (44%–64%). In CD lacking biopsy confirmation, overall agreement of plasma to serum was ≥98% for all antibodies, and 100% for venous to capillary plasma.

Conclusions

The Ig_plex Celiac Disease Panel increases the likelihood of confirming CD based on the post-test probability of disease results for multi-reactive markers. Specific positivity profiles and cut-off intervals can be used to monitor GFD treatment and likely disease progression. Using serum, venous and capillary plasma yield comparable and accurate results.

Dermatitis Herpetiformis: Novel Perspectives

Dermatitis herpetiformis (DH) is an inflammatory disease of the skin, considered the specific cutaneous manifestation of celiac disease (CD). Both DH and CD occur in gluten-sensitive individuals, share the same Human Leukocyte Antigen (HLA) haplotypes (DQ2 and DQ8), and improve following the administration of a gluten-free diet. Moreover, almost all DH patients show typical CD alterations at the small bowel biopsy, ranging from villous atrophy to augmented presence of intraepithelial lymphocytes, as well as the generation of circulating autoantibodies against tissue transglutaminase (tTG). Clinically, DH presents with polymorphic lesions, including papules, vesicles, and small blisters, symmetrically distributed in typical anatomical sites including the extensor aspects of the limbs, the elbows, the sacral regions, and the buttocks. Intense pruritus is almost the rule. However, many atypical presentations of DH have also been reported. Moreover, recent evidence suggested that DH is changing. Firstly, some studies reported a reduced incidence of DH, probably due to early recognition of CD, so that there is not enough time for DH to develop. Moreover, data from Japanese literature highlighted the absence of intestinal involvement as well as of the typical serological markers of CD (i.e., anti-tTG antibodies) in Japanese patients with DH. Similar cases may also occur in Caucasian patients, complicating DH diagnosis. The latter relies on the combination of clinical, histopathologic, and immunopathologic findings. Detecting granular IgA deposits at the dermal-epidermal junction by direct immunofluorescence (DIF) from perilesional skin represents the most specific diagnostic tool. Further, assessing serum titers of autoantibodies against epidermal transglutaminase (eTG), the supposed autoantigen of DH, may also serve as a clue for the diagnosis. However, a study from our group has recently demonstrated that granular IgA deposits may also occur in celiac patients with non-DH inflammatory skin diseases, raising questions about the effective role of eTG IgA autoantibodies in DH and suggesting the need of revising diagnostic criteria, conceivably emphasizing clinical aspects of the disease along with DIF. DH usually responds to the gluten-free diet. Topical clobetasol ointment or dapsone may be also applied to favor rapid disease control. Our review will focus on novel pathogenic insights, controversies, and management aspects of DH.