Diagnostic Delay in Dermatitis Herpetiformis in a High-prevalence Area

Primate liver tissue substrate in indirect immunofluorescence diagnostics for patients with dermatitis herpetiformis and celiac disease

Introduction

Dermatitis herpetiformis (DH) is a rare autoimmune, polymorphous blistering disorder, characterized by severe itch or burning sensation, which represents the cutaneous manifestation of celiac disease (CD). The current estimation of DH versus CD is around 1:8 and the affected individuals have a genetic predisposition. Pathogenetically, IgA autoantibodies against the epidermal transglutaminase, an essential constituent of the epidermis, cause DH and are reported to develop through cross-reaction with the tissue transglutaminase, with IgA auto-antibodies causing CD. Immunofluorescence techniques allow for a rapid diagnostics of the disease using patient sera. Evaluation of IgA endomysial deposition with indirect immunofluorescence on monkey oesophagus is highly specific, but moderately sensitive, with some operator-dependent variability. Recently, indirect immunofluorescence with monkey liver as a substrate has been proposed as an alternative, well-functioning diagnostic approach with higher sensitivity in CD.

Methods

The objective of our study was to evaluate whether monkey oesophagus or liver tissue shows advantage for diagnostics in patients with DH, compared to CD. To that end, sera of 103 patients with DH (n=16), CD (n=67) and 20 controls ere compared by 4 blinded experienced raters.

Results

For DH, we found a sensitivity of 94.2% for monkey liver (ML) compared to 96.2% in monkey oesophagus (ME), while specificity in ML was superior (91.6% versus 75%) to ME. In CD, ML had a sensitivity of 76.9% (ME 89.1%) and specificity of 98.3% (ME 94.1%).

Discussion

Our data show that ML substrate is well suitable for DH diagnostics.

Sex-differences in Gluten-free Dietary Adherence and Clinical Symptoms in Patients with Long-term Treated Dermatitis Herpetiformis

Dermatitis herpetiformis is a blistering autoimmune skin disease, and a cutaneous manifestation of coeliac disease. The burden of coeliac disease is increased especially in females, but studies concerning sex differences in patients with long-term treated dermatitis herpetiformis are scarce. This questionnaire study compared adherence to a gluten-free diet, clinical symptoms and well-being between females and males in a cohort of 237 long-term treated (median 24 years) patients with dermatitis herpetiformis. Females had better adherence to a gluten-free diet (p = 0.022) and they used dapsone significantly less often at the time of the study than did males (4% vs 13%, p = 0.017). The occurrence of skin symptoms was equal in both sexes, but dermatological quality of life was lower in females (p = 0.024), and gastrointestinal symptoms were more severe among females with dermatitis herpetiformis than among males (p = 0.027). In conclusion, long-term treated female patients with dermatitis herpetiformis have better adherence to a gluten-free diet, but they also experience more severe clinical symptoms compared with males.

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.

THE MANAGEMENT OF DERMATITIS HERPETIFORMIS BY THE GASTROENTEROLOGIST. A SERIES OF CASES

BACKGROUND

Dermatitis herpetiformis (DH) is considered a skin celiac disease (CD). The individuals can be seen by primary care professionals or by dermatologists that could refer the patient to a gastroenterologist.

OBJECTIVE

The study aimed to investigate the clinical profile of patients diagnosed with DH and referred to a gastroenterologist and evaluate the treatment response.

METHODS

We retrospectively studied patients with DH referred to the same gastroenterologist at a private office in Curitiba, Brazil, between January 2010 to December 2019. We included adult patients with a confirmed DH diagnosis. Symptoms, clinical signs, laboratory and histological data, as well as treatment response, were collected.

RESULTS

Thirty-three patients were studied (60.6% women, mean age at diagnosis 40.8±12.61 years). The median delay for DH diagnosis was four years. Skin involvement was mild in 33.3%, moderate in 18.2%, and severe in 48.5%. The more frequent gastrointestinal complaints were abdominal distension (78.8%), flatulence (75.7%), and gastroesophageal reflux (51.5%). Depression and anxiety were observed in 81.8% and anemia in 51.1%. A higher prevalence of bone disorders was associated with higher age at DH diagnosis (P=0.035). Duodenal biopsy showed changes in all patients. Improvement after treatment only with a gluten-free diet (GFD) plus dapsone was verified in 81.2%.

CONCLUSION

Patients with DH referred to a gastroenterologist showed a high frequency of gluten intolerance and systemic complaints. Duodenal histological alterations were found in all the cases. The treatment based on GFD plus dapsone was effective in most patients.

Evaluation of a Bi-Analyte Immunoblot as a Useful Tool for Diagnosing Dermatitis Herpetiformis

Immune responses to tissue transglutaminase (tTG) and nonapeptides of gliadin (npG) are associated with dermatitis herpetiformis (DH), a gluten-related dermatosis. Recently, a bi-analyte immunoblot (b-aIB) was introduced to detect IgA antibodies in response to tTG and npG. We compared the utility of ELISA and b-aIB with tTG in serological diagnoses of DH and their agreement with direct immunofluorescence (DIF). In total, 55 sera (27 DIF-positive DH patients, 4 DIF-negative DH patients and 24 healthy controls) were examined. ELISA for anti-tTG IgA, b-aIB for anti-npG and anti-tTG IgA, and statistical analysis were performed. The b-aIB with tTG showed 78% sensitivity, 100% specificity, 100% positive predictive value, and 82% negative predictive value in relation to ELISA. A better rate of agreement (Cohen’s kappa values) in IgA detection was observed in the pair tTG ELISA and b-aIB with npG (0.85) than in pairs tTG ELISA and b-aIB with tTG (0.78) or b-aIB with tTG and b-aIB with npG (0.78). No degree of agreement was found between serological tests and DIF. Both serological tests may be used to detect the anti-tTG IgA in DH patients. Still, DH diagnosing requires careful consideration of clinical data as well as results of tissue imaging (crucial DIF) and immunoserological techniques detecting DH-type features.

S2k guidelines (consensus statement) for diagnosis and therapy of dermatitis herpetiformis initiated by the European Academy of Dermatology and Venereology (EADV)

INTRODUCTION

Dermatitis herpetiformis (DH) is a chronic, pruritic, gluten-induced skin disorder characterized by subepidermal granular IgA deposition and a variable degree of enteropathy identical to that seen in coeliac disease. So far, there has been no European consensus about the management of DH.

METHODS

The guidelines were created by small subgroups of a guideline committee consisting of 26 specialists from various medical fields and one patients' representative. The members of the committee then discussed the guidelines and voted for the final version at two consensus meetings. The guidelines were developed under the support of the European Academy of Dermatology and Venereology (EADV) and in collaboration with the European Dermatology Forum (EDF).

RESULTS

The guidelines summarize evidence-based and expert-based recommendations (S2 level) for the management of DH (see Appendix).

CONCLUSION

These guidelines will improve the quality of management of DH and support dermatologists in their diagnostic and therapeutic decisions.

Dermatitis Herpetiformis: An Update on Diagnosis and Management

Dermatitis herpetiformis (DH), presenting with an intense itch and blistering symmetrical rash, typically on the elbows, knees, and buttocks, is a cutaneous manifestation of celiac disease. Though overt gastrointestinal symptoms are rare, three-fourths of patients with DH have villous atrophy in the small bowel, and the rest have celiac-type inflammatory changes. DH affects mostly adults and slightly more males than females. The mean age at onset is about 50 years. DH diagnosis is confirmed by showing granular immunoglobulin A deposits in the papillary dermis. The DH autoantigen, transglutaminase 3, is deposited at the same site in tightly bound immune complexes. At present, the DH-to-celiac disease prevalence is 1:8. The incidence of DH is decreasing, whereas that of celiac disease is increasing, probably because of improved diagnostics. In DH, the treatment of choice for all patients is a gluten-free diet (GFD) in which uncontaminated oats are allowed. At onset, most patients need additional dapsone to rapidly control the rash and itching. Dapsone can be stopped after a mean of 2 years, and a strict lifelong GFD alone is required. Dietary adherence offers an excellent long-term prognosis for patients with DH, with a normal quality of life and all-cause mortality.

Pitfalls in the Diagnosis of Coeliac Disease and Gluten-Related Disorders

The spectrum of gluten-related disorders (GRD) has emerged as a relevant phenomenon possibly impacting on health care procedures and costs worldwide. Current classification of GRD is mainly based on their pathophysiology, and the following categories can be distinguished: immune-mediated disorders that include coeliac disease (CD), dermatitis herpetiformis (DH), and gluten ataxia (GA); allergic reactions such as wheat allergy (WA); and non-coeliac gluten sensitivity (NCGS), a condition characterized by both gastrointestinal and extra-intestinal symptoms subjectively believed to be induced by the ingestion of gluten/wheat that has recently gained popularity. Although CD, DH, and WA are well-defined clinical entities, whose diagnosis is based on specific diagnostic criteria, a diagnosis of NCGS may on the contrary be considered only after the exclusion of other organic disorders. Neither allergic nor autoimmune mechanisms have been found to be involved in NCGS. Mistakes in the diagnosis of GRD are still a relevant clinical problem that may result in overtreatment of patients being unnecessary started on a gluten-free diet and waste of health-care resources. On the basis of our clinical experience and literature, we aim to identify the main pitfalls in the diagnosis of CD and its complications, DH, and WA. We provide a practical methodological approach to guide clinicians on how to recognize and avoid them.

The Long-Term Safety and Quality of Life Effects of Oats in Dermatitis Herpetiformis

The treatment of choice for dermatitis herpetiformis (DH), a cutaneous manifestation of coeliac disease, is a life-long gluten-free diet (GFD). In a GFD, wheat, rye and barley should be strictly avoided, but the role of oats is more controversial. This study aimed to investigate the safety and long-term quality of life and health effects of oat consumption in 312 long-term treated DH patients. Baseline data were gathered from patient records and follow-up data from questionnaires or interviews, and validated questionnaires were used to assess quality of life. We found that altogether 256 patients (82%) were consuming oats as part of their GFD at the follow-up. Long-term follow-up data showed that there were no differences in the presence of long-term illnesses, coeliac disease complications or the usage of medication between those consuming and not consuming oats. However, oat consumers had a better quality of life and reported ongoing gastrointestinal symptoms less frequently (4% vs 19%, p = 0.004) at the follow-up than those not consuming oats. The study established that oats are safe for DH patients and in the long-term seem to improve the quality of life of DH patients.

Female Patients with Dermatitis Herpetiformis Show a Reduced Diagnostic Delay and Have Higher Sensitivity Rates at Autoantibody Testing for Celiac Disease

Objective

Our objective was to characterize the demographic information, clinical features, and laboratory data of patients with dermatitis herpetiformis (DH).

Methods

In this multicentre cross-sectional study, consecutive patients with a new diagnosis of DH that referred to nine different Italian centers between 2011 and 2016 were characterized assessing demographic, clinical and laboratory findings, and evaluating gender and age differences across selected variables.

Results

A total of 151 patients were included. Among them, 81 (53.6%) were males and 70 (46.4%) were females, with a male to female ratio of 1.2 : 1. The median age at the time of diagnosis was 41 years (range 0-85). Males had a significant longer diagnostic delay if compared to females (9 vs. 3 months, respectively; p = 0.01). Direct immunofluorescence was positive in 94.7% of the patients, while duodenal biopsy showed partial to total villous atrophy in 70.1% of patients. All the females resulted positive to at least one of the antibodies tested, while a total of 12 male patients (10.5%) tested negative to celiac-specific antibodies. Female patients had a high rate (14.1%) of autoimmune thyroiditis.

Conclusions

Our study confirmed some of the most relevant data regarding DH that have been previously reported in the literature. In addition, we found a reduced diagnostic delay in females with respect to males, possibly related to the higher sensitivity of serologic testing in females with DH compared to males. Finally, we demonstrated that intestinal involvement could be severe in patients with DH and that females should be tested for thyroiditis.

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.

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.

Coeliac crisis mimicking nephrotic syndrome in a post-partum patient

BACKGROUND

Coeliac crisis is a life-threatening presentation of coeliac disease. Severe diarrhoea, weight loss, electrolyte imbalances and malnutrition are prominent features. Although mainly a disease of childhood, it can on the rare occasion be diagnosed in adults.

CASE PRESENTATION

A 25-year-old female with severe generalised oedema, lower extremity weakness, hypokalemia and profound hypoalbuminemia was referred with an initial diagnosis of nephrotic syndrome. Three months previously she had given birth to a healthy child following an uneventful pregnancy. She did not have proteinuria. She had a history of diarrhoea with gluten-containing food since childhood but lacked a formal diagnosis of coeliac disease. A duodenal biopsy confirmed the suspected diagnosis. Coeliac crisis was diagnosed with life-threatening multisystem involvement. Introduction of a gluten-free diet abolished all disease symptoms and ameliorated laboratory parameters at six months' follow-up.

CONCLUSION

Coeliac crisis is a rare, yet dangerous presentation of coeliac disease in adults. As this case suggests, it can present with generalised oedema and hypoalbuminemia mimicking nephrotic syndrome. Rapid diagnosis is the key to successful treatment.

Prognosis of Dermatitis Herpetiformis Patients with and without Villous Atrophy at Diagnosis

Dermatitis herpetiformis (DH) is a cutaneous manifestation of coeliac disease. At diagnosis, the majority of patients have villous atrophy in the small bowel mucosa. The objective of this study was to investigate whether the presence or absence of villous atrophy at diagnosis affects the long-term prognosis of DH. Data were gathered from the patient records of 352 DH and 248 coeliac disease patients, and follow-up data via questionnaires from 181 DH and 128 coeliac disease patients on a gluten-free diet (GFD). Of the DH patients, 72% had villous atrophy when DH was diagnosed, and these patients were significantly younger at diagnosis compared to those with normal small bowel mucosa (37 vs. 54 years, p < 0.001). Clinical recovery on a GFD did not differ significantly between the DH groups, nor did current adherence to a GFD, the presence of long-term illnesses, coeliac disease-related complications or gastrointestinal symptoms, or quality of life. By contrast, the coeliac disease controls had more often osteopenia/osteoporosis, thyroid diseases, malignancies and current gastrointestinal symptoms compared to the DH patients. In conclusion, villous atrophy at the time of DH diagnosis does not have an impact on the clinical recovery or long-term general health of DH patients.

Dermatitis Herpetiformis: A Common Extraintestinal Manifestation of Coeliac Disease

Dermatitis herpetiformis (DH) is a common extraintestinal manifestation of coeliac disease presenting with itchy papules and vesicles on the elbows, knees, and buttocks. Overt gastrointestinal symptoms are rare. Diagnosis of DH is easily confirmed by immunofluorescence biopsy showing pathognomonic granular immunoglobulin A (IgA) deposits in the papillary dermis. A valid hypothesis for the immunopathogenesis of DH is that it starts from latent or manifest coeliac disease in the gut and evolves into an immune complex deposition of high avidity IgA epidermal transglutaminase (TG3) antibodies, together with the TG3 enzyme, in the papillary dermis. The mean age at DH diagnosis has increased significantly in recent decades and presently is 40⁻50 years. The DH to coeliac disease prevalence ratio is 1:8 in Finland and the United Kingdom (U.K.). The annual DH incidence rate, currently 2.7 per 100,000 in Finland and 0.8 per 100,000 in the U.K., is decreasing, whereas the reverse is true for coeliac disease. The long-term prognosis of DH patients on a gluten-free diet is excellent, with the mortality rate being even lower than for the general population.