Coeliac syndrome in dermatitis herpetiformis

Morphea as Part of the Dermatological Manifestation of Celiac Disease: Case Presentation and Review of the Literature

Celiac disease is an immune-mediated disease, affecting multiple systems and organs including several dermatological conditions. Morphea, or localized scleroderma, is also an immune-mediated condition, in which an association with celiac disease has not thus far been recognized. We present an interesting case report of a 10-year-old child with a recent diagnosis of celiac disease presenting with morphea. Following treatment and adherence to a gluten-free diet, the morphea rapidly resolved. We suggest a possible relationship between the two entities and give a brief review of the relevant literature. We suggest that morphea might be one of the many dermatological manifestations of celiac disease, with possible implications for the need to screen patients with morphea for celiac disease.

Declining trend in the incidence of biopsy-verified coeliac disease in the adult population of Finland, 2005-2014

BACKGROUND

The frequency of coeliac disease (CD) has been on the rise over the past decades, especially in Western Europe, but current trends are unclear.

AIM

To research the recent temporal changes in the incidence of adult, biopsy-verified coeliac disease and dermatitis herpetiformis (DH) in Finland, a country with a high frequency of coeliac disease.

METHODS

All coeliac disease and DH cases diagnosed at age 20-79 years during 2005-2014 were retrieved from a nationwide database documenting all applicants for monthly compensation to cover the extra cost of maintaining a gluten-free diet. This benefit is granted on the basis of histology, not socioeconomic status. Temporal trends in the annual incidences were estimated using Poisson regression analyses.

RESULTS

The total incidence of coeliac disease decreased from 33/100 000 during the years 2005-2006 to 29/100 000 during 2013-2014. The mean annual incidence of coeliac disease was nearly twice as high among women as among men, 42 vs 22 per 100 000, respectively. For middle- and old-aged women, the average rate of decrease in incidence was 4.8% (95% CI 3.9-5.7) per year and for men 3.0% (1.8-4.1) (P for linear trend <.001, for both). Similarly, the annual incidence of DH declined. For young adults, the rate of change remained low and nonsignificant throughout the period 2005-2014.

CONCLUSIONS

Although the awareness of coeliac disease has increased during the past decades, the incidence of biopsy-verified diagnoses is not increasing, which suggests that exposure to yet unidentified triggering factors for coeliac disease has plateaued among the Finnish adult population.

Pathophysiology of dermatitis herpetiformis: a model for cutaneous manifestations of gastrointestinal inflammation

Dermatitis herpetiformis (DH) is an autoimmune blistering skin disease in which antigen presentation in the gastrointestinal mucosa results in cutaneous IgA deposition and distinct, neutrophil-driven cutaneous lesions. Our findings suggest that the qualitatively different immune response to gluten in the intestinal mucosa of patients with DH results in minimal clinical symptoms, allowing the continued ingestion of gluten and the eventual development of DH. Our model may provide a new way to understand the pathogenesis of other skin diseases associated with gastrointestinal inflammation such as pyoderma gangrenosum or erythema nodosum, or explain association of seronegative inflammatory arthritis with inflammatory bowel disease.

Approach to the patient with autoimmune mucocutaneous blistering diseases

Autoimmune mucocutaneous blistering diseases (AMBD) are a rare group of dermatoses that can be potentially fatal. There are many subtypes and their clinical presentation can vary from being localized to general involvement. It is crucial that a diagnosis be made as early as possible and appropriate treatments are implemented. This article will discuss the diagnosis and available treatments of the major AMBDs. There are very few case-controlled studies regarding the treatments of these diseases. Most of the treatments used for these diseases are based on anecdotal reports. Hence, a synopsis of the conventional treatments and some brief recommendations will also be discussed. A brief discussion regarding "rescue" therapies that have been used for those patients with more recalcitrant cases of AMBD will also be presented.

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.

Glomerulonephritis in dermatitis herpetiformis. A case study

A patient with dermatitis herpetiformis, proteinuria and reduced renal function is described. A renal biopsy studied by light and immunofluorescence microscopy revealed a glomerulonephritis with deposits of predominantly IgA and complement C3. Deposits of IgA and C3 were also demonstrated in a biopsy from normal skin, and a common pathway for the skin and renal lesions is suggested.

Clinical, pathologic, and immunopathologic features of dermatitis herpetiformis: review of the Mayo Clinic experience

BACKGROUND

Dermatitis herpetiformis (DH) is a cutaneous manifestation of gluten sensitivity, occasionally associated with other autoimmune disorders, and reportedly associated with an increased risk of lymphoproliferative disorders. We describe a series of patients with DH, focusing on associated disorders (particularly celiac disease), incidence of lymphoma, histopathology, and sensitivity of direct immunofluorescence (DIF) testing and serologic testing with antiendomysium antibodies for the diagnosis of DH.

METHODS

The medical records of 264 patients with DH diagnosed between 1970 and 1996 were reviewed retrospectively. In addition, the records of six patients evaluated before the advent of DIF testing between 1932 and 1969 were reviewed.

RESULTS

Established celiac disease was present in 12.6% of patients with DH, autoimmune systemic disorders in 22.2%, malignant neoplasms in 10.4%, sarcoidosis in four patients, and ulcerative colitis in six patients. Lymphoproliferative disorders were found in seven patients. The histopathologic examinations showed a marked predominance of neutrophils in the inflammatory infiltrate. DIF testing was positive in 92.4% of the patients tested. Indirect immunofluorescence assay indicated circulating antiendomysial antibodies in the sera of 40 of the 63 patients tested (63.5%).

CONCLUSIONS

In this large series of patients with DH from a single institution, patients had a low incidence of symptomatic gluten-sensitive enteropathy, low risk of lymphoproliferative disorders, and associations with other systemic autoimmune disorders. The value of DIF testing in the diagnosis of DH was confirmed. The detection of antiendomysial antibodies by indirect immunofluorescence was less sensitive than indicated by other reports.

Cutaneous spectrum of coeliac disease

Coeliac disease is characterized by gluten intolerance and immunologically mediated damage to small intestinal mucosa. Patients classically present with gastrointestinal symptoms including chronic diarrhoea, steatorrhoea, weight loss, anorexia and abdominal distension. In a substantial proportion of cases however, gastrointestinal symptoms are minor or absent, and cutaneous manifestations may provide an early clue to diagnosis. Early recognition of coeliac disease, with appropriate implementation of a gluten-free diet, may reduce the incidence of benign and malignant complications associated with this condition.

Further studies of anti-endomysium and anti-gliadin antibodies in patients with suspected celiac disease

BACKGROUND

The finding of characteristic small intestinal mucosal abnormalities on histologic examination of a biopsy specimen remains the first requirement for the diagnosis of celiac disease. A reliable and noninvasive test would be ideal for the patient's convenience and for reducing health-care costs. The sensitivity and specificity of anti-gliadin antibodies (AGA-immunoglobulin [Ig] G, AGA-IgA) have been variable; anti-endomysium IgA (EmA-IgA) is more helpful. In an earlier study conducted at the authors' institution, celiac disease was present in 19 patients examined from 1992 to 1995. Anti-endomysium titers were higher than normal in all 19 patients (100%). Total villous atrophy was seen in 14 of 17 biopsy specimens (82%) and subtotal atrophy in 3 (18%). The purpose of the current study was to evaluate further the accuracy of EmA-IgA in diagnosing celiac disease.

METHODS

One hundred seven patients were screened for celiac disease between March 1996 and July 1997. The level of EmA-IgA was measured in all patients, and AGA-IgG and AGA-IgA were measured in 104 patients. Forty-six patients underwent endoscopic biopsy of the small bowel, with measurement of disaccharidase enzymes in 45 patients.

RESULTS

Five of 46 patients had celiac disease (three boys and two girls; mean age, 5.3 years; 2-9.5 years); one also had cystic fibrosis and another had insulin-dependent diabetes mellitus. All five had marked to complete villous atrophy with crypt hyperplasia and increased serum EmA-IgA (100% sensitivity). None of the remaining patients had increased EmA-IgA (100% specificity). Serum levels of AGA-IgG and AGA-IgA were increased in all four celiac disease patients (100% sensitivity), but they were also high in patients without celiac disease (38% and 92% specificity, respectively), which compromises their diagnostic value. None of the patients confirmed to have celiac disease had IgA deficiency. Abnormal disaccharidase enzyme activities were documented in all five celiac disease patients: severe generalized deficiency (n = 2), moderately severe generalized deficiency (n = 2), and alactasia with moderate deficiency of the alpha-glucosidases (n = 1).

CONCLUSIONS

This study confirmed the reliability and accuracy of EmA-IgA in the diagnosis of celiac disease. Small bowel biopsy may be unnecessary in EmA-positive patients in whom celiac disease is suspected.

Secretor status and human leucocyte antigens in coeliac disease

BACKGROUND

The ability to secrete blood group antigens into body fluids and secretions is controlled by a single gene on chromosome 19. By means of erythrocyte Lewis (Le) antigen phenotype secretor status can be inferred. An increase prevalence of non-secretors of blood group antigens among coeliac patients has recently been described.

METHODS

Blood was collected from 112 coeliac patients and 103 controls and tested for secretor status. Secretor status was correlated with human leucocyte antigens (HLA) in coeliac patients, thus evaluating a proposed interaction of susceptibility genes--that is, the secretor gene on chromosome 19 and HLA-linked genes on chromosome 6. Case notes for coeliacs were reviewed with regard to clinical outcome.

RESULTS

Of 112 coeliacs who had either Le(a) or Le(b) antigens, 36 (32%) were non-secretors Le(a+, b-), compared with 27% (28) of 103 disease-free controls (P = 0.313). Recessive Lewis phenotype Le(a-, b-) was found in 9% of coeliacs versus 2% of controls. Prevalence of HLA-A1, B8, DR3, and DQ2 was unrelated to secretor status in coeliac versus patients. An increased prevalence of complications and coeliac-associated abnormalities was found in the non-secreting and recessive coeliac groups.

CONCLUSIONS

This study shows no firm relationship between the non-secretor state and coeliac disease, nor any difference in the distribution of HLA markers among secretor and non-secretor coeliacs. It is unlikely, therefore, that the secretor gene is the much sought-after second coeliac gene.

25 years' experience of a gluten-free diet in the treatment of dermatitis herpetiformis

Gluten-free diets have been used in the treatment of patients with dermatitis herpetiformis in our department since 1967. Of the 212 patients with dermatitis herpetiformis attending between 1967 and 1992, 133 managed to take the diet, and 78 of these achieved complete control of their rash by diet alone. Of the remaining 55 patients taking a gluten-free diet, all but three were taking partial diets; over half of these patients managed to substantially reduce the dose of medication required. Of the 77 patients taking a normal diet, eight entered spontaneous remission, giving a remission rate of 10%; a further two patients who had been taking gluten-free diets were found to have remitted when they resumed normal diets. Loss of IgA from the skin was observed in 10 of 41 (24%) patients taking strict gluten-free diets. These patients had been taking their diets for an average of 13 years (range 5-24 years), and their rash had been controlled by diet alone for an average of 10 years (range 3-16 years). The advantages of a gluten-free diet in the management of patients with dermatitis herpetiformis are: (i) the need for medication is reduced or abolished; (ii) there is resolution of the enteropathy, and (iii) patients experience a feeling of well-being after commencing the diet. Thus, we propose that a gluten-free diet is the most appropriate treatment for patients with dermatitis herpetiformis.

Inhibition of neutrophil adherence to antibody by dapsone: a possible therapeutic mechanism of dapsone in the treatment of IgA dermatoses

Dapsone is frequently effective in cutaneous diseases characterized by antibody deposition and accumulation of neutrophils. We hypothesized that this mechanism of action of dapsone may involve the inhibition of neutrophil adherence to antibody. The neutrophil adherence assay, which measures the binding of neutrophils to basement membrane zone-bound antibody on skin sections, was used to evaluate the effect of dapsone on neutrophil adherence to immunoglobulin A and immunoglobulin G. We evaluated the effect of dapsone on adherence of normal neutrophils to immunoglobulin A and immunoglobulin G from sera of linear immunoglobulin A bullous dermatosis and bullous pemphigoid patients, respectively. Linear immunoglobulin A bullous dermatosis or bullous pemphigoid antibody were bound to the basement membrane zone of normal skin sections as a substrate for the neutrophil adherence assay. Dapsone was added directly to the neutrophils or to the antibody source in concentrations of 0-50 micrograms/ml (pharmacologic range). Addition of dapsone to neutrophils produced an incremental inhibition of neutrophil adherence up to 75% at 50 micrograms/ml. Dapsone produced similar inhibition when added directly to the antibody itself, despite washing prior to usage in the neutrophil-adherence assay. Control specimens including irrelevant fractions of patient sera failed to demonstrate binding. Serum from a patient on dapsone therapy also showed inhibition of neutrophil adherence compared to the same patient on no therapy. We conclude that dapsone inhibits the adherence of neutrophils to basement membrane zone antibody in a dose-dependent manner. This may be related to an effect directly on antibody. This inhibition may contribute to the clinical efficacy of dapsone in antibody-mediated diseases.

Comparison of the intestinal and serum antibody response in patients with dermatitis herpetiformis

Dermatitis herpetiformis (DH) is an intensely pruritic, blistering skin disease characterized by cutaneous IgA deposits and an associated, most often asymptomatic, gluten-sensitive enteropathy. When patients with DH are placed on a gluten-free diet both the intestinal abnormality and the cutaneous manifestations of the disease are controlled, suggesting that a mucosal immune response is important in the pathogenesis of DH. Although patients with DH continue to ingest gluten only 40-50% have evidence of an ongoing mucosal immune response in their serum. In order to investigate directly the mucosal immune response in patients with DH the antibody response to dietary antigens was analyzed in intestinal secretions and compared to that found in the serum. Intestinal secretions from six patients with DH and five normal subjects were collected using an intestinal lavage solution and analyzed for total IgA, IgG, IgM, and IgA subclasses, and for IgG, IgA, and IgM antibodies against the dietary antigens bovine beta-lactoglobulin and gliadin. Intestinal secretions from patients with DH contained more IgA than those from normal subjects (mean total IgA: DH = 2.3 mg/ml; normal subjects (NL) = 0.143 mg/ml, P = 0.017). This increase in IgA in intestinal secretions from patients with DH was composed primarily of IgA1 (intestinal IgA: 86% IgA1, 14% IgA2; NL gut secretions: IgA1 = 54%; IgA2 = 46%). Increased IgA antibodies directed against beta-lactoglobulin and gliadin were detected in gut secretions of two of six patients with DH and in none of the normal subjects. Serum IgA antibodies against beta-lactoglobulin and gliadin were detected only in the two subjects who had detectable IgA antibodies in their intestinal secretions. Serum and intestinal IgA anti-beta-lactoglobulin antibodies had similar isoelectric spectrotypes (pI 5.0-6.5), IgA subclass composition, and antigenic reactivity by immunoblot analysis, demonstrating the close relationship between the serum and intestinal IgA antibodies. These data demonstrate that in patients with DH an ongoing mucosal immune response is present in the gut as evidenced by a significantly increased concentration of IgA, predominately IgA1. The strong correlation between detectable serum and intestinal IgA antibodies against dietary antigens demonstrates that the lack of serum IgA antibodies against dietary antigens in some patients with DH is not due to the presence of "blocking" IgA anti-dietary antigen antibodies in intestinal secretions.(ABSTRACT TRUNCATED AT 400 WORDS)

The effect of an elemental diet with and without gluten on disease activity in dermatitis herpetiformis

Elemental diets are reported to decrease activity of patients with dermatitis herpetiformis. We tested the hypothesis that gluten, given in addition to an elemental diet, is responsible for the intestinal abnormalities, cutaneous immunoreactant deposition, and skin disease activity in dermatitis herpetiformis. At entry eight patients with dermatitis herpetiformis, who were consuming unrestricted diets, were stabilized on their suppressive medications at dosage levels that allowed individual lesions to erupt. Six patients were then given an elemental diet plus 30 of gluten for 2 weeks, followed by the elemental diet alone for 2 weeks. Conversely, two patients received an elemental diet alone for 2 weeks followed by an elemental diet plus gluten during the final 2 weeks. Small bowel biopsies, skin biopsies, and clinical assessments were done at 0, 2, and 4 weeks. Suppressive medication dose requirement decreased over the 4 weeks by a mean of 66%. Six of eight subjects significantly improved clinically during the gluten-challenge phase of the elemental diet and all were improved at the end of the study. The amount of IgA in perilesional skin did not change significantly, but the amount of C3 increased in five of seven evaluable subjects after gluten challenge. Circulating anti-gluten and anti-endomysial antibodies were not significantly affected by the diets. All subjects completing evaluable small bowel biopsies (seven of seven) demonstrated worsening of their villus architecture (by scanning electron microscopy and intraepithelial lymphocyte counts) during gluten challenge and improvement (six of six subjects) after 2 weeks of elemental dietary intake. We conclude that 1) there is a significant improvement in clinical disease activity on an elemental diet, independent of gluten administration, 2) small bowel morphology improves rapidly on an elemental diet, and 3) complement deposition but neither IgA deposition nor circulating antibody levels correlate with gluten intake. It seems likely that dietary factors other than gluten are important in the pathogenesis of the skin lesions in dermatitis herpetiformis.

Characterization of the mucosal immune response to dietary antigens in patients with dermatitis herpetiformis

The association of dermatitis herpetiformis (DH) with granular IgA deposits at the dermal-epidermal junction and a gluten sensitive enteropathy (GSE) suggests that a mucosal immune response may play an important role in the pathogenesis of DH. The degree of antigenic restriction, the immunoglobulin class and subclass response to dietary antigens, and the relationship of antibodies against dietary antigens to IgA-containing circulating immune complexes (CIC) in patients with DH, however, are not known. We have examined the serum of 33 patients with DH for IgG and IgA antibodies against gliadin, and against 3 dietary proteins not thought to be related to GSE, beta-lactoglobulin (beta-lacto), bovine gamma globulin (BGG), and casein. Eleven of 33 (33%) patients with DH had IgA anti-gliadin antibodies, whereas IgA antibodies against beta-lacto were found in 11 of 33 patients (33%), against BGG in 15 of 32 (47%), and against casein in 6 of 33 (18%); 17 of 32 (53%) patients had IgA antibodies against one or more of these dietary antigens. Significantly higher levels of IgA antibodies were detected against beta-lacto (2,500 +/- 2,320 ng/ml, mean +/- SEM) and BGG (2,340 +/- 1,890 ng/ml) than gliadin (1,250 +/- 851 ng/ml) in this group of antibody positive patients (p less than 0.05, Wilcoxon signed ranks test). Eleven of 17 patients with IgA antibodies against dietary antigens were found to have IgA-containing CIC, whereas only one of the 15 antibody negative patients had IgA-containing CIC (p = 0.0008, Fisher's exact test). IgA anti-gliadin antibodies were found to contain both IgA1 and IgA2 with a significantly increased proportion of IgA2 when compared with the IgA2 composition of the total serum IgA (IgA2: anti-gliadin antibodies = 34 +/- 4.2%; total serum IgA = 19 +/- 4.8%, p = 0.02, Students paired t test). IgG antibodies against these antigens were found to occur slightly more frequently in amounts not significantly greater than IgA antibodies. This data demonstrates that a serum IgA and IgG antibody response to dietary antigens occurs in approximately 50% of DH patients with a higher proportion of IgA2 than total serum IgA and does not appear to be restricted to gliadin. This is significantly different from the pattern of cutaneous immunoreactants in patients with DH, and suggests that the deposition of IgA in DH skin may be the result of an atypical mucosal immune response, a non-immunologic interaction of IgA1 and DH skin, or arise from a non-mucosal source.

Prevalence of duodenal and jejunal lesions in dermatitis herpetiformis

Sixty-eight patients with dermatitis herpetiformis underwent jejunal suction biopsies and/or multiple endoscopic duodenal biopsies to evaluate the incidence of small bowel mucosal atrophy and to compare the diagnostic yield of the two methods. Small bowel function tests were also performed to evaluate the extent of functional impairment. Small bowel lesions were observed in 89.4% of jejunal suction biopsies and in 100% of endoscopic duodenal biopsies. Of the 10 patients who underwent both procedures, one had lesions only in the duodenum, one had more severe lesions in the duodenum than in the jejunum, while the remaining 8 patients showed identical lesions at both sites. The 1-h blood d-xylose test after a dose of 5 g proved more sensitive than xylosuria or serum folic acid assay in detecting subclinical malabsorption. Finally, histological features of gluten-sensitive enteropathy can be found in nearly 100% of patients with dermatitis herpetiformis. Upper gastrointestinal endoscopy with duodenal biopsies is at least as sensitive as jejunal suction biopsy in assessing small bowel involvement in dermatitis herpetiformis.

The pathogenesis of dermatitis herpetiformis: recent advances

Over the last two decades a rapid expansion of our knowledge regarding dermatitis herpetiformis has occurred, including the discovery of IgA in the skin, the discovery of an associated gluten-sensitive enteropathy, the noting of an increased prevalence of the human lymphocyte antigens (HLA)-B8 and -DRw3, and the documentation that the skin disease of many dermatitis herpetiformis patients can be controlled by a gluten-free diet. It has also been noted that two distinct forms of dermatitis herpetiformis occur, those with granular deposits of IgA at the dermoepidermal junction (85%-95% of dermatitis herpetiformis patients) and those with linear IgA deposits (10%-15% of dermatitis herpetiformis patients). These findings are reviewed with particular emphasis on the form of dermatitis herpetiformis associated with granular IgA deposits. The current findings regarding the nature and origin of the cutaneous IgA deposits, the role of the gluten-sensitive enteropathy, and the spectrum of both the immunologic and the nonimmunologic abnormalities associated with dermatitis herpetiformis are presented, and from these data pathophysiologic mechanisms are proposed that may be involved in dermatitis herpetiformis.

Long-term follow-up of dermatitis herpetiformis in children

Dermatitis herpetiformis was diagnosed in seventy-six children by its clinical features and by detection of granular IgA deposits in the papillary dermis of perilesional skin. Enteric alterations demonstrated by measurement of D-xylose absorption and by small intestinal biopsies were detected in over 90% of all patients. A complete follow-up was obtained for all children who were followed for 3 to 10 years. Treatment with a gluten-free diet alone led to a reversal of the intestinal abnormality in 100% of our children and to the disappearance of cutaneous lesions in 82% of reported cases. This suggests that a complete remission of symptoms can be obtained with a gluten-free diet alone. Dapsone alone is effective therapy for the rash but does not affect the intestinal alterations. Furthermore, the lack of side effects to dietetic therapy for a long period of time makes the diet the treatment of choice in this disease.

Serum antibodies to gliadin and small-intestinal morphology in dermatitis herpetiformis. A controlled clinical study of the effect of treatment with a gluten-free diet

Serum gliadin antibodies of the IgA and IgG classes were determined by the diffusion-in-gel enzyme-linked immunosorbent assay in 41 patients with dermatitis herpetiformis before treatment with a gluten-free diet. Increased gliadin antibody levels were found more frequently in patients with subtotal villous atrophy (9 out of 17 patients, or 53%; p less than 0.05) than in patients with partial villous atrophy (2 out of 13 patients, or 15%) or normal villous appearance (2 out of 10 patients, or 20%). The gliadin antibody levels were negatively correlated with the urinary xylose excretion (r = -0.40, p less than 0.02 for the IgA class and r = -0.64, p less than 0.001 for the IgG class). Intestinal morphology improved and mean gliadin antibody levels of the IgA and IgG classes decreased during treatment with a gluten-free diet for 16-36 months (mean, 20 months) (p less than 0.005, n = 26), whereas no significant changes of the gliadin antibody levels or the small-intestinal morphology were observed in the other 15 patients, who continued on a non-restricted diet for 17-35 months (mean, 20 months). Thus, gliadin antibody levels in sera from patients with dermatitis herpetiformis seem to be correlated with the severity of the intestinal disease. However, all patients with villous atrophy are not detected by determination of serum gliadin antibodies.

Evidence that the IgA in patients with linear IgA disease is qualitatively different from that of patients with dermatitis herpetiformis

A previous study using immunofluorescent techniques showed J-chain to be present in the uninvolved skin of patients with papillary IgA dermatitis herpetiformis (DH) in a distribution that was coextensive with the IgA. This implied that the IgA was dimeric and of mucosal origin. In this study, fifteen patients with papillary IgA deposits, fifteen with homogeneous-linear (HL) IgA deposits and four patients with granular-linear (GL) IgA deposits were tested for the presence of in vivo bound J-chain. All fifteen patients with papillary IgA deposits and all four with GL IgA deposits had J-chain staining coextensive with the IgA. However, only one of fifteen patients with HL IgA deposits demonstrated in vivo bound J-chain that could not be accounted for by coexisting IgM deposits. These findings indicate that the IgA in patients with HL deposits is qualitatively different from that in patients with papillary and GL IgA deposits and makes the distinction between the two types of linear fluorescence particularly important.

Conventional malabsorption tests: do they detect the adult patient with villous atrophy?

A total number of 134 patients with subtotal or partial villous atrophy, of whom 49 had dermatitis herpetiformis, were investigated with blood folate assay and xylose and lactose absorption tests. Faecal fat excretion was determined in 71 patients without dermatitis herpetiformis (coeliac group). A comparison was made between three patient groups, the patients with dermatitis herpetiformis and the coeliac patients studied in 1970-74 and 1975-79, respectively. From clinical and biochemical analyses of these patients we conclude that although a combination of the four malabsorption tests used here still detect a majority of coeliac patients, small intestinal biopsy may reveal villous atrophy also in patients without any laboratory evidence for malabsorption by these commonly used tests. In dermatitis herpetiformis, however, the sensitivity of the tests used was low; these malabsorption tests therefore have little diagnostic value in this category of patients.

Dermatitis herpetiformis: diagnosis, diet and demography

We describe a long term study of 76 patients with dermatitis herpetiformis. Unlike patients with coeliac disease, where the peak incidence was during the first and fourth decades, no dermatitis herpetiformis patients presented in the first decade; also, there was a male preponderance in dermatitis herpetiformis which contrasts with the excess of females in coeliac disease. The apparent prevalence of dermatitis herpetiformis was 11 per 100 000 in our population; approximately one fifth of that of coeliac disease. Jejunal villous atrophy was present in 78% of our dermatitis herpetiformis patients, and a single jejunal biopsy was as effective at detecting this as the multiple biopsy technique. A majority of patients were able to stop, or radically reduce their dapsone or sulphapyridine treatment after the institution of a gluten free diet. Spontaneous remission of the skin lesion occurred in only two patients not receiving a gluten free diet. Gastric parietal or thyroid antibodies were detected in 38% of patients, and three cases of thyroid disease and two cases of pernicious anaemia were detected. Lymphoma developed in two patients, one being intestinal in origin. We conclude that a gluten free diet is of therapeutic benefit in dermatitis herpetiformis and that spontaneous remission is uncommon in those not on a diet. Despite patchiness of the enteropathy, a single jejunal biopsy is quite adequate to diagnose the presence of upper intestinal villous atrophy.

Sequential studies of gliadin antibodies in patients with dermatitis herpetiformis

Sequential studies of circulating gliadin antibodies (IgG, IgA, IgM, IgD) were performed in 24 patients with dermatitis herpetiformis (DH) by an ELISA. Three groups of patients were studied: (a) 14 patients who responded to a gluten-free diet and were able to stop their drug therapy, (b) 5 patients who did not respond to a gluten-free diet, (c) 5 patients with normal jejunal biopsies, who did not receive a gluten-free diet. Most of the serum gliadin antibodies detected were of IgG class, but in several patients IgA gliadin antibodies were found in addition. When the patients were on a normal diet, 63% had elevated IgG gliadin antibody titres (titres which exceeded the maximum titre of the controls by one dilution) and there were no significant differences between the three groups. When the patients were followed up, there was a significant fall in the gliadin antibody titres in those who responded to a gluten-free diet compared to the two other groups of patients. Thus assays of IgG gliadin antibodies might be helpful in some patients in judging the compliance of patients on a gluten-free diet.

Increased gliadin antibodies in dermatitis herpetiformis and pemphigoid

The mean titres of serum IgG and IgA gliadin antibodies were significantly increased in thirty-four patients with bullous pemphigoid, and in twenty-three patients with dermatitis herpetiformis, compared with twenty-four healthy controls. The patients with pemphigoid also had increased IgG and IgA gliadin antibodies compared with nine patients with pemphigus. The reason for the high titres of gliadin antibodies in pemphigoid is obscure. These patients may have increased intestinal permeability (suggested by the presence of beta-lactoglobulin antibodies in some patients). Alternatively gliadin may somehow precipitate the autoimmune process.