Targeted serum proteome profiling reveals nicotinamide adenine dinucleotide phosphate (NADPH)-related biomarkers to discriminate linear IgA bullous disorder from dermatitis herpetiformis.

Linear IgA bullous dermatosis (LABD) and dermatitis herpetiformis (DH) represent the major subtypes of IgA mediated autoimmune bullous disorders. We sought to understand the disease etiology by using serum proteomics. We assessed 92 organ damage biomarkers in LABD, DH, and healthy controls using the Olink high-throughput proteomics. The positive proteomic serum biomarkers were used to correlate with clinical features and HLA type. Targeted proteomic analysis of IgA deposition bullous disorders vs. controls showed elevated biomarkers. Further clustering and enrichment analyses identified distinct clusters between LABD and DH, highlighting the involvement of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Comparative analysis revealed biomarkers with distinction between LABD and DH and validated in the skin lesion. Finally, qualitative correlation analysis with DEPs suggested six biomarkers (NBN, NCF2, CAPG, FES, BID, and PXN) have better prognosis in DH patients. These findings provide potential biomarkers to differentiate the disease subtype of IgA deposition bullous disease.

Patient-reported burden of skin disorders in coeliac disease.

OBJECTIVES: The current knowledge on the associations between coeliac disease and different skin diseases is contradictory and the patient's perspective on the burden of these is lacking. This study aimed to investigate patient-reported frequency, severity and quality of life effects of skin disorders in coeliac disease patients compared to controls and moreover to study the impacts of gluten-free diet on these skin diseases. MATERIALS AND METHODS: A study questionnaire designed for the purposes of this study and a validated Dermatology Life Quality Index (DLQI) questionnaire were posted to 600 adult members of the Finnish Coeliac Society and 1173 matched controls. Responses from 327 coeliac disease patients and 382 non-coeliac controls were compared. RESULTS: Coeliac disease patients were shown to be at no increased risk of atopic dermatitis, acne, rosacea, psoriasis, alopecia areata, vitiligo or chronic urticaria. The severity of these skin diseases did not differ between study groups, but the risk for at least moderate effects on quality of life caused by dermatological diseases was increased among those with coeliac disease. Positive response from gluten-free diet was most commonly experienced by coeliac disease patients with atopic dermatitis. CONCLUSIONS: Even though the risk for skin diseases was shown not to be increased among coeliac disease patients, there is still an increased burden related to experienced skin symptoms among these patients, which non-dermatologists treating coeliac disease patients should acknowledge.

Role of Human Leukocyte Antigen Class II in Antibody-Mediated Skin Disorders.

HLA class II molecules are key factors determining susceptibility to autoimmune disorders, and their role in immune-mediated skin conditions such as psoriasis has been extensively investigated. However, there is currently little understanding of their role in antibody-mediated skin diseases such as autoimmune blistering disorders. We researched the available literature using PubMed to narratively review the current knowledge on HLA associations in antibody-mediated blistering skin pathologies. Our results summarized the risk alleles that are identified in the literature, together with certain known protective alleles: in the pemphigus group, alleles HLA-DQB1*0503 and HLA-DRB1*0402 are most commonly associated with disease; in the pemphigoid group, the most studied allele is HLA-DQB1*0301; in epidermolysis bullosa acquisita, few genetic studies are available; in dermatitis herpetiformis, the association with haplotypes HLA-DQ2 and HLA-DQ8 is strongly established; finally, in linear IgA bullous disease, specific HLA alleles may be responsible for pediatric presentations. Our current pathogenic understanding of this group of disorders assigns a key role to predisposing HLA class II alleles that are able to bind disease autoantigens and therefore stimulate antigen-specific autoreactive T cells. The latter engage B lymphocytes that will produce pathogenic autoantibodies. The distribution of HLA alleles and their disease associations are variable across demographics, and an in-depth pathogenetic understanding is needed to support associations between HLA alleles and disease phenotypes. Additionally, in a personalized medicine approach, the identification of HLA alleles associated with the risk of disease may become clinically relevant in identifying susceptible subjects that should avoid exposure to known triggers, such as medication, when possible.

The risk of renal comorbidities in celiac disease patients depends on the phenotype of celiac disease.

BACKGROUND: An increased risk of kidney disease in patients with celiac disease has been reported, but the association has remained obscure. Only few studies have investigated the association between renal comorbidities and dermatitis herpetiformis, a cutaneous manifestation of celiac disease. OBJECTIVES: We investigated whether patients with different phenotypes of celiac disease are at higher risk of kidney diseases than age- and sex-matched references. METHODS: The diagnoses of glomerulonephritis, diabetic nephropathy, interstitial nephritis, and end-stage renal disease obtained from the National Hospital Discharge Register between 1970 and 2015 were identified in celiac disease (Marsh III, n = 1072) and dermatitis herpetiformis (n = 368) patients diagnosed at Tampere University Hospital catchment region and in 4296 reference subjects. Using the Cox proportional hazards model, we compared the risk of kidney diseases between patients and references. The study protocol was approved by the Regional Ethics Committee of Tampere University Hospital (R16090). As the study was register based, no consent from patients was required. RESULTS: Even after adjusting for type 1 diabetes, celiac disease was associated with an elevated risk of kidney disease (hazard ratio [HR] 1.85, 95% confidence interval [CI] 1.12-3.03), glomerulonephritis (HR 3.37, 95% CI 1.64-6.95), and IgA nephropathy (IgAN) (HR 18.98, 95% CI 2.29-157.63). No similarly elevated risk was found among dermatitis herpetiformis patients (HR 1.50, 95% CI 0.63-3.55; HR 2.21, 95% CI 0.77-6.38; and HR 5.87, 95% CI 0.53-64.79, respectively). CONCLUSION: Celiac disease patients were at increased risk of kidney diseases, notably IgAN. The risk was dependent on the celiac disease phenotype and was not seen in patients with dermatitis herpetiformis. Awareness of possible renal manifestations is recommended when treating celiac disease patients.

Antibody Responses to Transglutaminase 3 in Dermatitis Herpetiformis: Lessons from Celiac Disease.

Dermatitis herpetiformis (DH) is the skin manifestation of celiac disease, presenting with a blistering rash typically on the knees, elbows, buttocks and scalp. In both DH and celiac disease, exposure to dietary gluten triggers a cascade of events resulting in the production of autoantibodies against the transglutaminase (TG) enzyme, mainly TG2 but often also TG3. The latter is considered to be the primary autoantigen in DH. The dynamics of the development of the TG2-targeted autoimmune response have been studied in depth in celiac disease, but the immunological process underlying DH pathophysiology is incompletely understood. Part of this process is the occurrence of granular deposits of IgA and TG3 in the perilesional skin. While this serves as the primary diagnostic finding in DH, the role of these immunocomplexes in the pathogenesis is unknown. Intriguingly, even though gluten-intolerance likely develops initially in a similar manner in both DH and celiac disease, after the onset of the disease, its manifestations differ widely.

Etiopathogenesis of dermatitis herpetiformis.

Dermatitis herpetiformis is a rare chronic, autoimmune bullous disease linked to gluten sensitivity with intense pruritus and characteristic skin eruptions. Etiopathogenesis is complex and not fully understood. It is currently considered to be a specific cutaneous manifestation of celiac disease. Genetic, environmental and immunological factors influence both conditions. Exposure to gluten is the starting point of an inflammatory cascade leading to the formation of circulating IgA antibodies against tissue transglutaminase and skin immune IgA deposition followed by skin lesions. Binding of the immune complex deposits of IgA transglutaminases and epidermal antibodies with enzymes in the papillary dermis stimulates complement activation, neutrophil influx, proinflammatory cytokine release and overproduction of matrix metalloproteinases. We have collected current knowledge of the pathogenesis of dermatitis herpetiformis.

In vitro diagnostics for the medical dermatologist. Part I: Autoimmune tests.

Despite the expansion of available in vitro laboratory tests at a rate far exceeding that of dermatologic pharmaceuticals, the existing literature is dominated by discussion of the latter. With the advent of numerous new tests, it can be difficult for practicing dermatologists to stay up-to-date on the available options, methodologies, and recommendations for when to order one test over another. Understanding the inherent strengths and weaknesses of these options is necessary to inform appropriate ordering and proper interpretation of the results. The first article in this continuing medical education series summarizes information on methodology, test characteristics, and limitations of several in vitro laboratory tests used for the work up of undifferentiated patients suspected of having dermatologic autoimmune diseases and it provides a general guide to ordering these tests.

Subepithelial autoimmune blistering dermatoses: Clinical features and diagnosis.

Subepithelial autoimmune blistering dermatoses are a group of rare skin disorders that are characterized by the disruption of the dermal-epidermal junction through the action of autoantibodies. The third article in this continuing medical education series explores the background, epidemiology, clinical features, and diagnostic criteria of each of the major subepithelial autoimmune blistering dermatoses, including bullous pemphigoid, pemphigoid gestationis, lichen planus pemphigoides, mucous membrane pemphigoid, linear IgA bullous dermatosis, and dermatitis herpetiformis.

Subepithelial autoimmune bullous dermatoses disease activity assessment and therapy.

Subepidermal (subepithelial) autoimmune blistering dermatoses are a group of rare skin disorders characterized by the disruption of the dermal-epidermal junction through the action of autoantibodies. The fourth article in this continuing medical education series presents the current validated disease activity scoring systems, serologic parameters, treatments, and clinical trials for bullous pemphigoid, mucous membrane pemphigoid, epidermolysis bullosa acquisita, bullous systemic lupus erythematosus, anti-p200 pemphigoid, linear IgA bullous dermatosis, and dermatitis herpetiformis.

Persistent Skin Symptoms after Diagnosis and on a Long-term Gluten-free Diet in Dermatitis Herpetiformis.

Dermatitis herpetiformis is a cutaneous manifestation of coeliac disease treated with a gluten-free diet. However, the itching and blistering rash alleviates slowly after gluten withdrawal and occasionally persists despite a long-term gluten-free diet. This study investigated the prevalence and factors associated with prolonged (i.e. >2 years) and ongoing skin symptoms in 237 patients with dermatitis herpetiformis. Data were gathered from medical records and via questionnaires. Among patients with dermatitis herpetiformis, 38% had prolonged symptoms after diagnosis, and 14% had ongoing skin symptoms at follow-up (median duration of gluten-free diet 24 years). A severe rash at diagnosis was associated with both prolonged and ongoing cutaneous symptoms. In addition, patients with dermatitis herpetiformis with ongoing skin symptoms at follow-up had been on the dietary treatment for a shorter time (median duration 16 vs 25 years) and were less often on a strict diet (53% vs 78%) compared with patients with dermatitis herpetiformis without ongoing skin symptoms.

Granular Deposits of IgA in the Skin of Coeliac Patients Without Dermatitis Herpetiformis: A Prospective Multicentric Analysis.

Granular deposits of IgA represent the specific cutaneous marker of dermatitis herpetiformis. The prevalence of IgA deposits in the skin of patients with coeliac disease without dermatitis herpetiformis remains unknown. In this prospective case-control study, skin biopsies from newly diagnosed coeliac patients without dermatitis herpetiformis were analysed by direct immunofluorescence. Controls included healthy volunteers and patients with both bowel symptoms and skin eruptions unrelated to coeliac disease. Clinical data and serum level of anti-tissue transglutaminase and anti-epidermal transglutaminase IgA antibodies were collected from patients and controls. Granular deposits of IgA or IgA1 in the skin were found in 29 out of 45 patients with coeliac disease (64.4%), and in none of the included controls (specificity 100%; sensitivity 64.4%). Positive direct immunofluorescence correlated significantly with an increased serum level of anti-epidermal transglutaminase IgA antibodies (p < 0.005). This study shows that granular deposits of IgA represent a low sensitive, but highly specific, cutaneous marker of coeliac disease independent of dermatitis herpetiformis.

Dermatitis Herpetiformis: An Update on Diagnosis, Disease Monitoring, and Management.

Dermatitis herpetiformis (DH), Duhring disease, is caused by gluten sensitivity and affects 11.2 to 75.3 per 100,000 people in the United States and Europe with an incidence of 0.4 to 3.5 per 100,000 people per year. DH is characterized by a symmetrical blistering rash on the extensor surfaces with severe pruritus. The diagnosis continues to be made primarily by pathognomonic findings on histopathology, especially direct immunofluorescence (DIF). Recently, anti-epidermal transglutaminase (TG3) antibodies have shown to be a primary diagnostic serology, while anti-tissue transglutaminase (TG2) and other autoantibodies may be used to support the diagnosis and for disease monitoring. Newly diagnosed patients with DH should be screened and assessed for associated diseases and complications. A gluten-free diet (GFD) and dapsone are still mainstays of treatment, but other medications may be necessary for recalcitrant cases. Well-controlled DH patients, managed by a dermatologist, a gastroenterologist, and a dietician, have an excellent prognosis. Our review comprehensively details the current diagnostic methods, as well as methods used to monitor its disease course. We also describe both the traditional and novel management options reported in the literature.

Current Concepts of Dermatitis Herpetiformis.

Dermatitis herpetiformis (DH) is an autoimmune skin disease that causes itchy, blistering rash, typically on the elbows, knees and buttocks. DH and coeliac disease share the same genetic background, gluten-dependent enteropathy and antibody response against tissue transglutaminase. DH is currently considered a cutaneous manifestation of coeliac disease, and the prevailing hypothesis is that DH develops as a late manifestation of subclinical coeliac disease. The incidence of DH is decreasing contemporarily with the increasing incidence of coeliac disease. The IgA immune response in DH skin is directed against epidermal transglutaminase, while the autoantigen in the gut is tissue transglutaminase. Granular IgA deposition in the papillary dermis is pathognomonic for DH, and is a finding used to confirm the diagnosis. The treatment of choice for DH is a life-long gluten-free diet, which resolves the rash and enteropathy, increases quality of life, and offers a good long-term prognosis.

Risk of fractures in dermatitis herpetiformis and coeliac disease: a register-based study.

Objectives: Dermatitis herpetiformis (DH) is a cutaneous manifestation of coeliac disease. Bone fracture risk is increased in coeliac disease, but little knowledge exists about bone complications in DH. This study aimed to evaluate the risk of hip and other hospital-treated fractures in DH and coeliac disease in a high prevalence area with good adherence to a gluten-free diet. Materials and methods: Hip, proximal humerus, wrist and ankle fractures in 368 treated DH and 1076 coeliac disease patients between 1970 and 2015 were reviewed from the National Hospital Discharge Register. Hip fracture incidence rates for DH and coeliac disease patients were compared to those for the general population. The overall fracture risk for DH was compared to coeliac disease. Results: The hip fracture incidence rates for DH and coeliac disease patients did not differ from the general population. In females aged 80-89, the hip fracture incidence was higher in DH than in coeliac disease, but the risk for any hospital-treated fracture was lower in DH compared to coeliac disease (adjusted HR 0.620, 95% CI 0.429-0.949). The DH and coeliac disease patients with hospital-treated fractures were diagnosed at an older age, but the degree of small bowel mucosal damage did not significantly differ between patients with and without fractures. Conclusion: The incidence of hip fracture is not increased in treated DH or coeliac disease in an area with high awareness and dietary compliance rates. However, patients with DH seem to have a lower risk for fractures overall compared to coeliac disease.

Sulfasalazine-induced generalized vitiligo in a patient with dermatitis herpetiformis and celiac disease.

Vitiligo is an acquired idiopathic pigmentary skin disorder characterized by the development of white macules and patches due to the loss of functioning melanocytes. In this report, we describe a case of a patient with a longstanding history of dermatitis herpetiformis (DH) and celiac disease that developed rapidly progressing, biopsy-confirmed generalized vitiligo after 11 months of treatment with anti-inflammatory medication sulfasalazine, prescribed for the patient's DH. To the best of our knowledge, this is the first case report which has demonstrated the possible biochemical pathways, triggered by sulfasalazine, in the development of vitiligo.

Facial Involvement in Dermatitis Herpetiformis: A Case Report and Review of the Literature.

Dermatitis herpetiformis is a cutaneous manifestation of celiac disease that classically presents as a symmetric pruritic vesicular eruption on extensor surfaces. Typical locations include elbows, knees, and buttocks. Facial involvement has been reported rarely. Here, we report a case of a 44-year-old woman with dermatitis herpetiformis presenting as pruritic vesicles on the face that had previously been misdiagnosed as allergic contact dermatitis. Diagnosis was confirmed with direct immunofluorescence demonstrating granular IgA in the papillary dermis. This eruption cleared with topical dapsone 5% gel and a gluten-free diet. We report this case to raise awareness of facial involvement in dermatitis herpetiformis as well as the possibility of topical dapsone as a therapeutic option.

[Autoimmune blistering dermatoses in children]. / Bullöse Autoimmundermatosen im Kindesalter.

Autoimmune blistering skin disorders represent a rare group of autoantibody-induced dermatoses against desmosomal and hemidesmosomal molecules. The common age of onset for pemphigus and pemphigoid, as well as dermatitis herpetiformis, encompasses the adult age, but all these disorders can be observed neonatally and/or during childhood. If the disease occurs postpartum or neonatally, physicians should consider transplacental transmission of pathogenic maternal immunoglobulin G (IgG)-autoantibodies, and both mother and child should be included in the diagnostic work up. If the disorder is suspected in childhood, early immunoserological testing and skin biopsies for direct immunofluorescence analyses are recommended for the correct diagnosis and subsequently for the right choice of treatment. First-line recommendations are nonhalogenated topical steroids, followed by oral dapsone. All therapies require preliminary examinations, e. g. enzyme-activity testing (as is glucose-6-phophate dehydrogenase in dapsone treatment). In refractory cases, further treatment choices like high-dose intravenous immunoglobins, plasmapheresis/immunoadsorption or targeted therapies like anti-CD20 autoantibody therapies are indicated. An intense dermatological support and good medical care are essential for an age-appropriate development of the child and to lower possible treatment-associated adverse events.

Celiac-Related Autoantibodies and IL-17A in Bulgarian Patients with Dermatitis Herpetiformis: A Cross-Sectional Study.

Background and objectives: Dermatitis herpetiformis (DH) is a blistering dermatosis, which shares common immunologic features with celiac disease (CD). The aim of the present study was to explore the performance of a panel of CD-related antibodies and IL-17A in Bulgarian patients with DH. Materials and Methods: Serum samples from 26 DH patients at mean age 53 ± 15 years and 20 healthy controls were assessed for anti-tissue transglutaminase (anti-tTG), anti-deamidated gliadin peptides (anti-DGP), anti-actin antibodies (AAA), and IL-17A by enzyme linked immuno-sorbent assay (ELISA), as well as anti-tTG, anti-gliadin (AGA), and anti-Saccharomyces cerevisiae antibodies (ASCA) using immunoblot. Results: The average serum levels of anti-tTG, anti-DGP, AGA, AAA, and the cytokine IL-17A were at significantly higher levels in patients with DH compared to the average levels in healthy persons which stayed below the cut-off value (p < 0.05). Anti-DGP and anti-tTG antibodies showed the highest diagnostic sensitivity and specificity, as well as acceptable positive and negative predictive value. None of the healthy individuals was found positive for the tested antibodies, as well as for ASCA within the DH group. All tests showed good to excellent correlations (r = 0.5 ÷ 0.9, p < 0.01). Conclusions: Although the diagnosis of DH relies on skin biopsy for histology and DIF, serologic testing of a panel of celiac-related antibodies could be employed with advantages in the diagnosing process of DH patients. Furthermore, DH patients who are positive for the investigated serologic parameters could have routine monitoring for gastrointestinal complications typical for the gluten-sensitive enteropathy.

An update on direct immunofluorescence for diagnosing dermatitis herpetiformis.

This mini-review presents an update on the direct immunofluorescence (DIF) for diagnosing dermatitis herpetiformis. The DIF of uninvolved, perilesional skin is a crucial laboratory procedure in diagnosing dermatitis herpetiformis (DH). IgA deposits at the dermal-epidermal junction (DEJ) of perilesional skin with DIF can also be found in coeliac patients with inflammatory skin diseases different from DH. In certain patients presenting with the rash resembling DH, the deposition of exclusively C3 at DEJ can be found. The term "granular C3 dermatosis" was proposed to name such a rash. Recent data on DH suggest that perhaps the very concept of DH that we are universally accepting now is misleading and should be revised.

Non-infectious diffuse vesiculobullous rash in a pancreas and renal transplant recipient.

Solid organ transplant patients are well established to be at risk of herpes simplex virus and varicella zoster virus infection and reactivation. We present a case of a 41-year-old woman with a history of pancreas and renal transplant who presented with what appeared to be disseminated herpes simplex virus or varicella zoster virus induced rash, but who was ultimately diagnosed and treated as linear IgA bullous dermatosis. This case alerts physicians to other non-infectious dermatoses as a cause of vesiculobullous rash in solid organ transplant patients.