Dermatitis herpetiformis

The emerging role of biotechnological advances and artificial intelligence in tackling gluten sensitivity

Gluten comprises an intricate network of hundreds of related but distinct proteins, mainly "gliadins" and "glutenins," which play a vital role in determining the rheological properties of wheat dough. However, ingesting gluten can trigger severe conditions in susceptible individuals, including celiac disease, wheat allergy, or non-celiac gluten sensitivity, collectively known as gluten-related disorders. This review provides a panoramic view, delving into the various aspects of gluten-triggered disorders, including symptoms, diagnosis, mechanism, and management. Though a gluten-free diet remains the primary option to manage gluten-related disorders, the emerging microbial and plant biotechnology tools are playing a transformative role in reducing the immunotoxicity of gluten. The enzymatic hydrolysis of gluten and the development of gluten-reduced/free wheat lines using RNAi and CRISPR/Cas technology are laying the foundation for creating safer wheat products. In addition to biotechnological interventions, the emerging artificial intelligence technologies are also bringing about a paradigm shift in the diagnosis and management of gluten-related disorders. Here, we provide a comprehensive overview of the latest developments and the potential these technologies hold for tackling gluten sensitivity.

A Rare Case of COVID-19-Induced Acute Exacerbation of Oral Dermatitis Herpetiformis in a Geriatric Patient

Introduction

Dermatitis herpetiformis (DH) is an autoimmune vesiculobullous disease associated with celiac enteropathy. The clinical manifestation of DH is the occurrence of a papulovesicular rash on the skin. Oral mucosal involvement in DH is very rare. This study aimed to describe the impact of COVID-19 on the acute exacerbation of oral dermatitis herpetiformis.

Case Report

A 74-year-old woman was referred to the Oral Medicine Department with a chief complaint of the blisters on the skin for a week and ulcers in the oral cavity appeared two days ago. Extraoral examination revealed crusts on the neck and extremities. The lips appeared dry and desquamative. Intraoral examination revealed erosive lesions covered with a white-yellowish plaques on the right and left sides of the buccal mucosa, an ulcer with a diameter of 0.5 cm, and purpura hemorrhagic on left buccal mucosa and right lateral border of the tongue. Histopathological examination of the skin lesion revealed a subepithelial blister with eosinophils and neutrophil cells. The definitive diagnosis of dermatitis herpetiformis was made. She was given 5 mg intravenous dexamethasone, cetirizine 10 mg, and clindamycin 300 mg by the dermatologist. We gave hyaluronic acid 0.025% mouthwash for oral ulcers and petroleum jelly for the lips. The oral lesions had significant improvement after 4 weeks of treatment. Two months later, the patient experienced acute exacerbation after being infected with COVID-19 (anti-SARS-CoV-2 IgG S-RBD >40,000 AU/mL). The oral lesions healed after a month of treatment.

Conclusion

COVID-19 can trigger the acute exacerbation of dermatitis herpetiformis. SARS-CoV-2 causes an immune dysregulation and hypersensitivity reaction.

A comprehensive insight into the anti-inflammatory properties of dapsone

The 4,4'-diaminodiphenyl sulfone (DDS), also known as dapsone, is traditionally used as a potent anti-bacterial agent in clinical management of leprosy. For decades, dapsone has been among the first-line medications used in multidrug treatment of leprosy recommended by the World Health Organization (WHO). Shortly after dapsone's discovery as an antibiotic in 1937, the dual function of dapsone (anti-microbial and anti-inflammatory) was elucidated. Dapsone exerts its anti-bacterial effects by inhibiting dihydrofolic acid synthesis, leading to inhibition of bacterial growth, while its anti-inflammatory properties are triggered by inhibiting reactive oxygen species (ROS) production, reducing the effect of eosinophil peroxidase on mast cells and downregulating neutrophil-mediated inflammatory responses. Among the leading mechanisms associated with its anti-microbial/anti-protozoal effects, dapsone clearly has multiple antioxidant, anti-inflammatory, and anti-apoptotic functions. In this regard, it has been described in treating a wide variety of inflammatory and infectious skin conditions. Previous reports have explored different molecular targets for dapsone and provided insight into the anti-inflammatory mechanism of dapsone. This article reviews several basic, experimental, and clinical approaches on anti-inflammatory effect of dapsone.

Pediatric Autoimmune Bullous Disease: A Literature Review and Update on Management

Pediatric autoimmune bullous disease is a rare group of blistering skin disorders in children that result from autoimmunity against intercellular and basement membrane antigens in the skin and mucous membranes. Most pediatric cases are treated with oral corticosteroids or longer-term immunosuppressants such as azathioprine or mycophenolate mofetil. Immunomodulating drugs such as rituximab are increasingly being considered as options for refractory disease.

Pruritus in Autoimmune and Inflammatory Dermatoses

Pruritus in autoimmune and inflammatory dermatoses is a common symptom that can be severe and affect the quality of life of patients. In some diseases, pruritus is related to disorders activity and severity or may occur independent of the disease. Despite the high prevalence, the symptom is still underrated and there are only a few trials investigating the efficacy of drugs for disease-specific pruritus. In this review, the characteristics and possible pathomechanisms of pruritus in various dermatoses like autoimmune bullous diseases, connective tissue diseases as well as autoimmune-associated dermatoses (atopic dermatitis, psoriasis vulgaris) is illustrated. Additionally, studies analyzing the antipruritic treatment are discussed. Summarizing, the prevalence of pruritus in these diseases demonstrates the importance for symptom recognition and the need for an efficient antipruritic therapy.

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.

The Role of Intereukin-31 in Pathogenesis of Itch and Its Intensity in a Course of Bullous Pemphigoid and Dermatitis Herpetiformis

Itch which is one of the major, subjective symptoms in a course of bullous pemphigoid and dermatitis herpetiformis makes those two diseases totally different than other autoimmune blistering diseases. Its pathogenesis is still not fully known. The aim of this research was to assess the role of IL-31 in development of itch as well as to measure its intensity. Obtained results, as well as literature data, show that lower concentration of IL-31 in patients' serum may be correlated with its role in JAK/STAT signaling pathway which is involved in development of autoimmune blistering disease. Intensity of itch is surprisingly huge problem for the patients and the obtained results are comparable with results presented by atopic patients.

Correlation between IL36α and IL17 and Activity of the Disease in Selected Autoimmune Blistering Diseases

Dermatitis herpetiformis (DH), bullous pemphigoid (BP), and pemphigus vulgaris (PV) are autoimmune bullous skin conditions with eosinophilic and neutrophilic infiltrations. While cytokines are crucial for the affinity and activation of different leukocyte cells in the inflammation and blister formation, there are no studies concerning a role of IL-36. The goal of the study was to analyze whether interleukin 36 is involved in pathogenesis of DH, BP, and PV. And the second aim of the study was the estimation of correlation between Il-36 and IL-17 and titers of specific antibodies in these diseases. Expression of IL-36 and IL-17 was detected in serum in all DH, BP, and PV samples. Serum levels of IL-36 and IL-17α were statistically higher in DH, BP, and PV groups as compared to the control group. IL-36α levels were statistically higher in DH patients, as compared to patients with PV and BP. Our results showed that IL-36 may be helpful in the diagnostic and monitoring of the activity of the disease. IL 36 may play a relevant role of enrolling eosinophils and neutrophils in DH, BP, and PV and finally provoke tissue injury.

Secoisolariciresinol Diglucoside and Cyanogenic Glycosides in Gluten-free Bread Fortified with Flaxseed Meal

Flaxseed (Linum usitatissimum L.) meal contains cyanogenic glycosides (CGs) and the lignan secoisolariciresinol diglucoside (1). Gluten-free (GF) doughs and baked goods were produced with added flaxseed meal (20%, w/w) then 1, and CGs were determined in fortified flour, dough, and bread with storage (0, 1, 2, and 4 weeks) at different temperatures (-18, 4, and 22-23 °C). 1 was present in flour, dough, and GF bread after baking. 1 was stable with extensive storage (up to 4 weeks) and was not affected by storage temperature. CGs in flaxseed meal and fortified GF samples were analyzed by ¹H NMR of the cyanohydrins. Linamarin and/or linustatin were the primary CGs in both flaxseed meal and fortified flour. CGs decreased with storage in dough fortified with flaxseed meal or GF bread after baking. GF bakery food products fortified with flaxseed meal had reduced CGs but remained a good source of dietary 1.

Utility of direct immunofluorescence testing for IgA in patients with high and low clinical suspicion for dermatitis herpetiformis

OBJECTIVES

The purpose of this study was to examine the utility of direct immunofluorescence (DIF) testing for the characteristic immunoglobulin A deposits of dermatitis herpetiformis (DH) in patients stratified into high and low clinical suspicion subgroups.

METHODS

We retrospectively analyzed the results of H&E and DIF testing in 77 cases of suspected DH and separated them into high and low clinical suspicion subgroups based on clinical impression at the time of biopsy.

RESULTS

The overall sensitivity and specificity of routine (H&E) histologic evaluation were 0.75 and 0.951, respectively. Although there were 13 cases of DH (of 36 total cases) in the high clinical suspicion subgroup, there were only three (of 41 total cases) in the low clinical suspicion subgroup. In the high clinical suspicion subgroup, the positive predictive value (PPV) was 0.9, and the negative predictive value (NPV) was 0.846. Alternatively, the PPV was 0.6 and the NPV was 1.0 for the low clinical suspicion subgroup. Histologic false negatives did occur, but all were in patients within the high clinical suspicion subgroup.

CONCLUSIONS

It is anticipated that the NPV and PPV will vary due to differing clinical practice characteristics; however, in patients with a low clinical suspicion for DH, these data argue that it may be reasonable to first perform a biopsy for routine histologic evaluation before requesting DIF analysis.

Celiac Disease: Background and Historical Context

Medical descriptions of celiac disease date to the first century BC, and the first modern description was published in 1888. Further insights were gained throughout the 1900s, culminating in the identification of the dietary component, the major genetic determinant, and the autoantigen by the turn of the century. Understanding of the age of onset, population prevalence, and the extent of subclinical celiac disease developed in tandem. Thanks to advances in genomics, currently established loci account for over 50 % of the genetic risk. Nonetheless, much remains to be discovered. Advances in high-throughput genomic, biochemical, and cell analyses, as well as the bioinformatics needed to process the data, promise to deepen our understanding further. Here we present a primer of celiac disease, viewing the condition in turn from the historical, epidemiological, immunological, molecular, and genetic points of view. Research into any ailment has specific requirements: study subjects must be identified and relevant tissue samples collected and stored with the appropriate timing and conditions. These requirements are summarized. To conclude, a short discussion of future prospects is presented.

Dermatitis herpetiformis: pathophysiology, clinical presentation, diagnosis and treatment

Researches on DH have shown that it is not just a bullous skin disease, but a cutaneous-intestinal disorder caused by hypersensitivity to gluten. Exposure to gluten is the starting point of an inflammatory cascade capable of forming autoantibodies that are brought to the skin, where they are deposited, culminating in the formation of skin lesions. These lesions are vesico-bullous, pruritic, and localized especially on elbows, knees and buttocks, although atypical presentations can occur. Immunofluorescence of perilesional area is considered the gold standard for diagnosis, but serological tests help in cases where it is negative. Patients who follow glutenfree diets have better control of symptoms on the skin and intestine, as well as lower risks of progression to lymphoma. Dapsone remains the main drug for treatment, but it requires monitoring of possible side effects, some potentially lethal.

Specific nongluten proteins of wheat are novel target antigens in celiac disease humoral response

While the antigenic specificity and pathogenic relevance of immunologic reactivity to gluten in celiac disease have been extensively researched, the immune response to nongluten proteins of wheat has not been characterized. We aimed to investigate the level and molecular specificity of antibody response to wheat nongluten proteins in celiac disease. Serum samples from patients and controls were screened for IgG and IgA antibody reactivity to a nongluten protein extract from the wheat cultivar Triticum aestivum Butte 86. Antibodies were further analyzed for reactivity to specific nongluten proteins by two-dimensional gel electrophoresis and immunoblotting. Immunoreactive molecules were identified by tandem mass spectrometry. Compared with healthy controls, patients exhibited significantly higher levels of antibody reactivity to nongluten proteins. The main immunoreactive nongluten antibody target proteins were identified as serpins, purinins, α-amylase/protease inhibitors, globulins, and farinins. Assessment of reactivity toward purified recombinant proteins further confirmed the presence of antibody response to specific antigens. The results demonstrate that, in addition to the well-recognized immune reaction to gluten, celiac disease is associated with a robust humoral response directed at a specific subset of the nongluten proteins of wheat.

Issues associated with the emergence of coeliac disease in the Asia–Pacific region: a working party report of the World Gastroenterology Organization and the Asian Pacific Association of Gastroenterology

BACKGROUND AND AIM

Once thought to be uncommon in Asia, coeliac disease (CD) is now being increasingly recognized in Asia–Pacific region. In many Asian nations, CD is still considered to be either nonexistent or very rare. In recognition of such heterogeneity of knowledge and awareness, the World Gastroenterology Organization and the Asian Pacific Association of Gastroenterology commissioned a working party to address the key issues in emergence of CD in Asia.

METHODS

A working group consisting of members from Asia–Pacific region, Europe, North America, and South America reviewed relevant existing literature with focus on those issues specific to Asia–Pacific region both in terms of what exists and what needs to be done.

RESULTS

The working group identified the gaps in epidemiology, diagnosis, and management of CD in Asian–Pacific region and recommended the following: to establish prevalence of CD across region, increase in awareness about CD among physicians and patients, and recognition of atypical manifestations of CD. The challenges such as variability in performance of serological tests, lack of population-specific cut-offs values for a positive test, need for expert dietitians for proper counseling and supervision of patients, need for gluten-free infrastructure in food supply and creation of patient advocacy organizations were also emphasized.

CONCLUSIONS

Although absolute number of patients with CD at present is not very large, this number is expected to increase over the next few years or decades. It is thus appropriate that medical community across the Asia–Pacific region define extent of problem and get prepared to handle impending epidemic of CD.

Molecular diagnosis in autoimmune skin blistering conditions

Blister formation in skin and mucous membranes results from a loss of cell-cell or cell-matrix adhesion and is a common outcome of pathological events in a variety of conditions, including autoimmune and genetic diseases, viral and bacterial infections, or injury by physical and chemical factors. Autoantibodies against structural components maintaining cell-cell and cell-matrix adhesion induce tissue damage in autoimmune blistering diseases. Detection of these autoantibodies either tissue-bound or circulating in serum is essential to diagnose the autoimmune nature of disease. Various immunofluorescence methods as well as molecular immunoassays, including enzyme-linked immunosorbent assay and immunoblotting, belong to the modern diagnostic algorithms for these disorders. There is still a considerable need to increase awareness of the rare autoimmune blistering diseases, which often show a severe, chronic-relapsing course, among physicians and the public. This review article describes the immunopathological features of autoimmune bullous diseases and the molecular immunoassays currently available for their diagnosis and monitoring.

Genetic polymorphisms of CYP2D6 oxidation in patients with autoimmune bullous diseases

INTRODUCTION

Bullous skin diseases, which include, among others pemphigoid, pemphigus, and dermatitis herpetiformis are classified as severe autoimmune dermatoses. It has been shown that a pattern of xenobiotic metabolism may play a role in the pathogenesis of autoimmune diseases.

AIM

To estimate whether the CYP2D6 genotype may be considered a predisposing factor in autoimmune bullous diseases induction.

MATERIAL AND METHODS

The study included 72 patients with autoimmune bullous diseases: 37 with pemphigoid, 21 with pemphigus, and 14 with dermatitis herpetiformis (DH). The CYP2D6 genotypes were analyzed by the polymerase chain reaction fragment length polymorphism (PCR-RFLP) method.

RESULTS

Relative risk of DH development for particular genotype carriers expressed by odds ratio (OR) was statistically significantly higher for subjects with CYP2D6*1/CYP2D6*4 (OR = 4.2; p = 0.0104) and 2-fold higher for subjects with CYP2D6*4 (OR = 2.3; p = 0.0351).

CONCLUSIONS

The results of the present study show that the CYP2D6 oxidation polymorphism cannot be considered a risk factor for development of pemphigoid and pemphigus, however it might have an impact on dermatitis herpetiformis.

Gene expression profiling in dermatitis herpetiformis skin lesions

Dermatitis herpetiformis (DH) is an autoimmune blistering skin disease associated with gluten-sensitive enteropathy (CD). In order to investigate the pathogenesis of skin lesions at molecular level, we analysed the gene expression profiles in skin biopsies from 6 CD patients with DH and 6 healthy controls using Affymetrix HG-U133A 2.0 arrays. 486 genes were differentially expressed in DH skin compared to normal skin: 225 were upregulated and 261 were downregulated. Consistently with the autoimmune origin of DH, functional classification of the differentially expressed genes (DEGs) indicates a B- and T-cell immune response (LAG3, TRAF5, DPP4, and NT5E). In addition, gene modulation provides evidence for a local inflammatory response (IL8, PTGFR, FSTL1, IFI16, BDKRD2, and NAMPT) with concomitant leukocyte recruitment (CCL5, ENPP2), endothelial cell activation, and neutrophil extravasation (SELL, SELE). DEGs also indicate overproduction of matrix proteases (MMP9, ADAM9, and ADAM19) and proteolytic enzymes (CTSG, ELA2, CPA3, TPSB2, and CMA1) that may contribute to epidermal splitting and blister formation. Finally, we observed modulation of genes involved in cell growth inhibition (CGREF1, PA2G4, and PPP2R1B), increased apoptosis (FAS, TNFSF10, and BASP1), and reduced adhesion at the dermal epidermal junction (PLEC1, ITGB4, and LAMA5). In conclusion, our results identify genes that are involved in the pathogenesis of DH skin lesions.

The expression of selected proapoptotic molecules in dermatitis herpetiformis

The role of the process of apoptosis is investigated in the pathogenesis of many autoimmune diseases; however at present, there is not much information about its role in dermatitis herpetiformis. Skin biopsies were taken from 18 DH patients and from 10 healthy subjects. The localization and expression of Bax, Fas, FasL, TRAIL, TRAIL-R in skin lesions, and perilesional skin were studied by immunohistochemistry. Expression of Bax, Fas, and Fas ligand was detected in the keratinocytes in skin biopsies from DH patients. Expression of TRAIL and TRAIL receptor was confirmed in epidermis, infiltration cells, and some fibroblasts. The expression of examined molecules in biopsies from healthy people was observed only in single cells. There were statistically significant differences between lesional, perilesional, and healthy skin of control group in Bax expression analysis and between lesional skin and control group in Fas, FasL, and TRAIL expression. There were statistically significant differences between control group and perilesional skin in Bax and FasL expression. Our results show that selected proapoptotic molecules may take part in pathogenesis of dermatitis herpetiformis, but the role of apoptosis in this process is not clear.

Distinct characteristics in Japanese dermatitis herpetiformis: a review of all 91 Japanese patients over the last 35 years

We reviewed all 91 Japanese dermatitis herpetiformis (DH) patients reported over the last 35 years. The male-to-female ratio was 2 : 1. The mean age at onset was 43.8, and 13 years earlier for female patients. More than half of these Japanese DH patients showed granular IgA deposition in the papillary dermis, and another one-third showed fibrillar IgA deposition. The male patients with granular IgA deposition were 10 years older than those with fibrillar deposition. Whereas patients with granular IgA deposition showed typical distribution of the skin lesions, the predilection sites of DH tended to be spared in patients with fibrillar IgA deposition. Only 3 patients had definite gluten-sensitive enteropathy. There was a statistical difference in the frequency of human leukocyte antigen (HLA)-DR9 between the granular group and controls among Japanese. No patients had HLA-DQ2 or -DQ8, which is frequently found in Caucasian DH patients. The absence of HLA-DQ2/DQ8, the inability to identify celiac disease in most cases, the predominance of fibrillar IgA, and the unusual distribution of clinical lesions in Japanese patients suggest that Japanese DH may be a subset of DH patients and have a pathogenesis which is different from that currently proposed in Caucasian DH patients.

Association between levels of IgA antibodies to tissue transglutaminase and gliadin-related nonapeptides in dermatitis herpetiformis

Dermatitis herpetiformis (DH) is an autoimmunity-driven inflammatory blistering dermatosis associated with a gluten-dependent enteropathy. Tissue transglutaminase (tTG) and nonapeptides of gliadin (npG) are considered in its pathomechanism/diagnostics. Here, the diagnostic accuracy of anti-tTG/anti-npG IgA ELISAs in Slavic DH patients with active skin rash was assessed through creating receiver operating characteristic (ROC) curves, determining cutoff values, and calculating correlations between levels of anti-tTG/anti-npG IgA in DH, IgA/neutrophil-mediated non-DH patients and healthy persons. Altogether, sera from 80 Slavic individuals were examined. There were negligible differences between cutoff points obtained by the ELISAs manufacturer and those in this study. There were statistically significant correlations between levels of anti-tTG/anti-npG IgA in both DH group and the group of IgA/neutrophil-mediated non-DH dermatoses. There was no such correlation in healthy controls. It seems that IgA autoantibodies to tTG and npG in the IgA/neutrophil-mediated DH are produced in the coordinated way implying their causal relationship.

Experiences with animal models of dermatitis herpetiformis: a review

Dermatitis herpetiformis (DH) is caused by the consumption of gluten, which is also the trigger for celiac disease. DH is currently considered to be the skin manifestation of celiac disease, as both diseases have some degree of gluten-sensitive enteropathy. The human leukocyte antigens class II genes, DQ2 and DQ8, are tightly associated with both diseases, and there is an increased level of anti-gliadin antibodies in both diseases. Animal models of gluten sensitivity have been used to better understand the pathogenesis of both diseases. This paper describes these different models and discusses how certain elements of these models contribute to the development of DH.

Autoimmunity-driven enzymatic remodeling of the dermal-epidermal junction in bullous pemphigoid and dermatitis herpetiformis

Pathogenesis of blister formation in bullous pemphigoid (BP) and dermatitis herpetiformis (DH) is associated with destruction of numerous components of the dermal--epidermal junction. Proteolytic enzymes (PE) are involved in a multitude of physiological reactions and may have impact on the epidermal--dermal integrity. Involvement of various PE in inflammation and blister formation in BP and DH is intensively investigated using both morphologic and functional approaches, particularly in BP. The development into the full-blown stage in BP and DH may be caused by an impairment of the human Fc receptor regulatory system that may cause the inefficiently controlled activation of inflammatory cells and subsequent secretion of various proteases.

Dermatitis herpetiformis. Part I. Epidemiology, pathogenesis, and clinical presentation

Dermatitis herpetiformis (DH) is an autoimmune disease that is linked to gluten sensitivity and has a clear relationship to celiac disease. Both conditions are mediated by the IgA class of autoantibodies and the diagnosis of DH is dependent on detection of granular deposits of IgA in the skin. There is an underlying genetic predisposition to the development of DH but environmental factors are also important. Typically, young adults present with excoriations only, as the severe pruritus effectively destroys any primary lesions. Based upon our experience with DH and a comprehensive literature review, we provide an update of DH epidemiology, pathophysiology, and clinical presentation.

[Dermatitis herpetiformis: a review]

BACKGROUND

Dermatitis herpetiformis (DH) is a rare auto-immune bullous disease characterized by its almost constant association to gluten sensitivity.

OBJECTIVE

Review of literature about epidemiology, physiopathology, clinical data and treatment of DH.

METHODS

Research on Medline and Embase database without any time limit until April 2010. Because of the lack of randomized therapeutic trials in DH, retrospective series and case reports have been analyzed.

RESULTS

DH is related to auto-antibodies against epidermal transglutaminase, which belongs to the same family as tissue transglutaminase, the auto-antigen of celiac disease. Physiopathology is complex, occurring in HLA DQ2 or DQ8 predisposed patients, and implies gluten, immunological reaction in the intestinal wall then in the skin. DH and celiac disease may be encountered in the same family. DH is characterized by a very pruritic microvesicular eruption typically located on elbows, knees and buttocks. Digestive manifestations of celiac disease occur in 15% of cases. Direct immunofluorescence is necessary to confirm the diagnosis, showing granular IgA±C3 deposits in the papillary dermis. Circulating IgA and IgG antiendomysium and antitransglutaminase antibodies are detected in almost all patients at the acute phase and follow the clinical course of the disease. Gastro-intestinal endoscopy with multiple duodenal biopsies shows partial or complete villous atrophy in two thirds of cases, intraepithelial lymphocyte infiltrate in the other cases. Other auto-immune diseases may be associated in 10-20% of cases. The main long-term risk is the occurrence of T or B nodal or intestinal tract lymphoma in 2% of cases (relative risk close to 6 in several studies, but not admitted by all authors), especially if adherence to gluten-free diet is not strict. Treatment is based on dapsone, which is quickly efficient on cutaneous manifestations, but not on the digestive involvement and on strict and definitive gluten-free diet, which cures villous atrophy and reduces the risk of lymphoma.

CONCLUSION

DH is associated to a gluten enteropathy and its physiopathology is better known. Even if the risk of secondary lymphoma seems little, most of the authors recommend a definitive gluten-free diet.

Celiac disease of the joint

A 42-year-old woman presented with a 3-week history of left knee pain and swelling. She had suffered dermatitis herpetiformis for 12 years, proved by skin biopsy. She had never been on gluten-free diet. Knee pain increased with motion and her gait was antalgic. On admission, she was mainly dependent on wheelchair due to pain and limitation. Treatment plan consisted of gluten-free diet, stretching and strengthening exercises, analgesic or nonsteroidal anti-inflammatory drugs when needed. She responded well to gluten-free diet. Association of joint involvement and dermatitis herpetiformis is more than just coincidental. Possible immunopathogenesis and role of gluten-free diet on arthritis treatment are discussed.

Autoimmune blistering diseases in children

Autoimmune blistering disorders comprise a series of conditions in which autoantibodies target components of the skin and mucous membranes, leading to blister and bullae formation. Most conditions in the spectrum of autoimmune blistering disorders are uncommonly seen in the pediatric population, even the most common ones, such as chronic bullous disease of childhood and dermatitis herpetiformis; however, they often come into the differential diagnosis of other more common pediatric entities. In addition, prompt recognition and treatment avoids unnecessary morbidity and improves ultimate outcome.

A long‐term gluten‐free diet as an alternative treatment in severe forms of dermatitis herpetiformis

BACKGROUND

A long-term gluten-free diet (GFD) as a first-choice treatment for dermatitis herpetiformis (DH) has been used successfully. The aim of the present study is to evaluate the possibility of treating all severe skin manifestations of DH by a GFD only.

METHODS

Seventy-two patients with DH were subdivided in two groups: group A (18 patients) underwent a GFD and received dapsone; group B (54 patients) underwent a GFD. Patients were subdivided into slight, moderate and severe forms.

RESULTS

A total of 88.9% of patients treated with dapsone and a GFD (group A) had remission of skin manifestations and the remaining 11.1% were improved. In group B, 87% of patients showed complete remission of skin manifestations after 18 months of a GFD; 13% showed improvement. With regard to severe forms, after an 18-month treatment, 70.4% of patients in group B; 66.6% in group A.

CONCLUSION

Our study shows that a GFD, if administered steadily and for a long period, can be a valid treatment for severe forms of DH. Dapsone can be useful to control the inflammatory phase of the disease.

A case of stiff-person syndrome, type 1 diabetes, celiac disease and dermatitis herpetiformis

Antibodies against glutamic acid decarboxylase (GAD) are involved in the pathophysiology of stiff-person syndrome (SPS) and type 1 diabetes. GAD catalyses the conversion of glutamate to gamma-aminobutyric acid (GABA). GABA acts as a neurotransmitter between neurones, while in pancreatic beta cells it plays an integral role in normal insulin secretion, hence the clinical presentation of muscular spasms in SPS and insulin deficiency in diabetes. Despite this apparent major overlap in pathophysiology, SPS only rarely occurs in individuals with type 1 diabetes. We report the case of a 41-year-old man presenting with a simultaneous diagnosis of both these conditions. His case is unusual in that it is the first reported case in the literature of these conditions occurring in someone with celiac disease (CD) and dermatitis herpetiformis. We discuss why SPS and type 1 diabetes co-exist in only a minority of cases and speculate on the underlying mechanism of the association with CD and dermatitis herpetiformis in our patient.

Celiac disease: from gluten to autoimmunity

Celiac disease, also known as gluten-sensitive enteropathy and nontropical sprue, is a prevalent autoimmune disorder that is triggered by the ingestion of wheat gluten and related proteins of rye and barley in genetically susceptible individuals. The immune response in celiac disease involves the adaptive, as well as the innate, and is characterized by the presence of anti-gluten and anti-transglutaminase 2 antibodies, lymphocytic infiltration in the epithelial membrane and the lamina propria, and expression of multiple cytokines and other signaling proteins. The disease leads to inflammation, villous atrophy, and crypt hyperplasia in the small intestine. In addition to the intestinal symptoms, celiac disease is associated with various extra-intestinal complications, including bone and skin disease, anemia, endocrine disorders, and neurologic deficits. Gluten-free diet is currently the only effective mode of treatment for celiac disease, but better understanding of the mechanism of the disease is likely to add other choices for therapy in the future.

Dermatitis herpetiformis and vitiligo

Dermatitis herpetiformis (DH) is a rare immunobullous disorder of the skin that is associated with gluten hypersensitivity. Subepidermal IgA-type antibody deposition against tissue transglutaminase leads to dense neutrophilic microabscess and eventually into vesicles in dermal papillae, which may occasionally merge into bullae. Being a subepidermal vesiculobullous disorder, DH is frequently associated with postinflammatory pigmentary changes, particularly hypopigmentation. However, the association of DH with true vitiligo is extremely rare. Here, we report a 21-year-old male with vitiligo and comorbid DH, and review the literature. This new case had severely pruritic, papular and papulovesicular lesions that were localized symmetrically and partly confined to the pre-existing vitiliginous areas. The skin biopsy specimen taken from an erythematous papule on the elbow showed characteristic findings of DH and vitiligo. Direct immunofluorescence microscopy of the perilesional skin revealed granular IgA deposition of dermal papillae. There are only 10 reports in the literature of DH and vitiligo comorbidity.

Bullous dermatoses in childhood: part II

Bullous dermatoses are commonly encountered in childhood practice. Much confusion exists among clinicians because of the similarity of clinical lesions, paucity of relevant literature, and varied nomenclature used for these diseases. For a better understanding of the proposed classification, this second part is a review of diseases with nonhereditary characteristics of subepidermal cleavage and hereditary characteristics with intraepidermal and subepidermal cleavage.

Immunopathology and molecular diagnosis of autoimmune bullous diseases

Autoimmune bullous diseases are associated with autoimmunity against structural components maintaining cell-cell and cell matrix adhesion in the skin and mucous membranes. Pemphigus diseases are characterized by autoantibodies against the intercellular junctions and intraepithelial blisters. In pemphigoid diseases and epidermolysis bullosa acquisita, sub-epidermal blistering is associated with autoantibodies targeting proteins of the hemidesmosomal anchoring complex. The autoantigens in autoimmune blistering diseases have been extensively characterized over the past three decades. In general, the pathogenicity of autoantibodies, already suggested by clinical observations, has been conclusively demonstrated experimentally. Detection of tissue-bound and circulating serum autoantibodies and characterization of their molecular specificity is mandatory for the diagnosis of autoimmune blistering diseases. For this purpose, various immunofluorescence methods as well as immunoassays, including immunoblotting, enzyme-linked immunosorbent assay and immunoprecipitation have been developed. This review article describes the immunopathological features of autoimmune bullous diseases and the immunological and molecular tests used for their diagnosis and monitoring.

The imbalance between metalloproteinases and their tissue inhibitors is involved in the pathogenesis of dermatitis herpetiformis

Dermatitis herpetiformis (DH) is a subepidermal autoimmune disease characterized by skin and intestinal lesions consistent with coeliac disease. There are also some data that metalloproteinases (MMPs) are involved in the development of skin lesions in DH, however their exact role in this process is not fully understood. The aim of the study was to investigate whether MMPs and their inhibitors are involved in pathogenesis of DH. Skin biopsies were taken from 13 patients with active DH and from 10 healthy subjects. The localization and expression of MMPs and TIMPs were examined by immunohistochemistry. MMPs expression was detected in basal keratinocytes and in the whole epidermis in all of the DH subjects. Neutrophils in microabscesses and in blister fluid were also positive for MMPs. Expression of TIMPs was moderate or weak in all examined biopsies. Our results allow us to conclude that imbalance between these enzymes takes an important role in the pathogenesis of DH.

Celiac disease

Celiac disease (CD) is a common autoimmune disorder, induced by the intake of gluten proteins present in wheat, barley and rye. Contrary to common belief, this disorder is a protean systemic disease, rather than merely a pure digestive alteration. CD is closely associated with genes that code HLA-II antigens, mainly of DQ2 and DQ8 classes. Previously, it was considered to be a rare childhood disorder, but is actually considered a frequent condition, present at any age, which may have multiple complications. Tissue transglutaminase-2 (tTG), appears to be an important component of this disease, both, in its pathogenesis and diagnosis. Active CD is characterized by intestinal and/or extra-intestinal symptoms, villous atrophy and crypt hyperplasia, and strongly positive tTG auto-antibodies. The duodenal biopsy is considered to be the "gold standard" for diagnosis, but its practice has significant limitations in its interpretation, especially in adults. Occasionally, it results in a false-negative because of patchy mucosal changes and the presence of mucosal villous atrophy is often more severe in the proximal jejunum, usually not reached by endoscopic biopsies. CD is associated with increased rates of several diseases, such as iron deficiency anemia, osteoporosis, dermatitis herpetiformis, several neurologic and endocrine diseases, persistent chronic hypertransami-nasemia of unknown origin, various types of cancer and other autoimmune disorders. Treatment of CD dictates a strict, life-long gluten-free diet, which results in remission for most individuals, although its effect on some associated extraintestinal manifestations remains to be established.

Unusual manifestations of celiac disease

Celiac disease is multifaced autoimmune disorder with several extraintestinal manifestations and connections to other autoimmune diseases and other conditions. The recognition of the complex clinical picture of the disease helps doctors to search and diagnose celiac disease even if the gastrointestinal symptoms are lacking. Individuals at risk for celiac disease should be thoroughly investigated and individuals with unusual manifestations of the disease should be screened actively.

Avancées moléculaires dans la physiopathologie des maladies bulleuses autoimmunes

Autoimmune blistering skin diseases are characterized by the production of autoantibodies directed against adhesive structures of the skin. These organ specific autoimmune diseases included pemphigus in which autoantibodies target proteins of the desmosomal complex, and subepidermal autoimmune diseases characterized by autoantibodies directed against structural proteins of the dermoepidermal junction. Binding of autoantibodies to their targets induces a loss of adhesion between keratinocytes in pemphigus and alterations of the dermoepidermal junction in subepidermal autoimmune diseases. Progresses during the last twenty years had allowed the identification of target autoantigens and the characterization of their adhesive functions, a better understanding of the pathogenesis of these diseases and the development of new diagnostic tools.

Gluten intolerance: gender- and age-related differences in symptoms

OBJECTIVE

Gluten intolerance is a common, immunologically mediated disorder with a widely variable clinical presentation that affects genetically predisposed subjects. Women seem to be more frequently affected although data on sex differences are poor. In this study the prevalence of different clinical pictures according to sex and age is analysed in a large series of patients.

MATERIAL AND METHODS

A total of 1436 patients with gluten intolerance were retrospectively considered, diagnosed from January 1975 to August 2001 based on compatible small-bowel biopsy and response to a gluten-free diet, plus immunofluorescent detection of granular IgA in papillary derma for dermatitis herpetiformis. The clinical picture at onset (classic, non-classic, silent) and age at diagnosis (< or = 2 years, > 2 and < or = 14 years, > 14 years) was recorded; 362 parents of coeliac probands undergoing a familial screening were also studied. The relations among sex, age class and symptoms were analysed using the chi2 test with Yates's correction.

RESULTS

The overall female/male ratio was 2.3:1 but the inter-sex difference was significant only when the diagnosis was made in adulthood where a significant association between iron-deficiency anaemia as manifestation at onset in adult women (34% versus 7%) was found. Low weight, dyspepsia and hypertransaminasaemia were more common in adult men than women (20%, 14% and 7% versus 13%, 3% and 2%, respectively). Dermatitis herpetiformis was present more frequently in men (16% versus 9%). The prevalence of silent cases was 6% in men and 3% in women. Familial screening showed the same prevalence (9.3%) of current coeliac disease in fathers and mothers.

CONCLUSIONS

Diagnosis of coeliac disease is more frequent in women but physicians' awareness of sex- and age-related differences in clinical presentation could improve diagnostic performances in men.

Dermatitis herpetiformis: close to unravelling a disease

Dermatitis herpetiformis is characterised by granular IgA precipitates in the papillary dermis. In contrast to other autoimmune blistering diseases, where tissue-deposited and circulating autoantibodies recognise the same target within the skin, in dermatitis herpetiformis a serum IgA reacting with a component of the healthy papillary dermis has not been detected. Recently, the antigenic specificity of pathognomic skin-bound IgA has been clarified: the immune precipitates contain epidermal transglutaminase, an enzyme not previously detected in the papillary region of normal skin. Furthermore, serum IgA in dermatitis herpetiformis has been found to bind epidermal transglutaminase. These findings may relate to the fact, that dermatitis herpetiformis is associated with gluten sensitive enteropathy, coeliac disease, which is characterised by IgA type autoantibodies to a closely related enzyme, tissue transglutaminase. The two transglutaminases are highly homologous, and therefore, cross reactivity of the two antibodies might explain why patients with gluten sensitive enteropathy, with or without skin disease, generally have serum autoantibodies to both enzymes. There is growing evidence that dermatitis herpetiformis should be considered as the skin manifestation of gluten sensitivity developing in those patients with mild coeliac disease, who produce epidermal transglutaminase autoantibodies of high avidity and affinity. Both the skin and the small bowel diseases are gluten dependent and are strongly associated with HLA DQ with no genetic differences to explain the two phenotypes. The question should be asked whether the rash in dermatitis herpetiformis is a classic autoimmune blistering disease or whether it has an immune complex basis, which is the most likely alternative.