The treatment of dermatitis herpetiformis

Dapsone in the Management of Pemphigus and Pemphigoid: Rediscovery of its Long-Lost Efficacy

Introduction

Autoimmune mucocutaneous blistering dermatoses (AMCBD) are a group of disorders characterized by the production of autoantibodies that target specific adhesion molecules of the skin and/or mucous membranes. As a result, there is blister formation on the skin with or without mucous membrane involvement. Systemic corticosteroids have been used as the mainstay of treatment in AMCBD. However, due to the debilitating side effects associated with their use, there is significant morbidity and mortality, especially on the fragile elderly patients. Although the efficacy of dapsone in the treatment of AMCBD was identified decades ago, few recent studies shed light on that. Hence, further studies are needed to evaluate the efficacy of dapsone as a single agent in maintaining disease remission in patients with AMCBD.

Materials and methods

An observational retrospective study was performed. Patients with a known diagnosis of bullous pemphigoid (BP) or pemphigus vulgaris (PV) who are treated with dapsone with or without low-dose systemic corticosteroids were included in the study, and their medical files were reviewed. 

Results

A total of seven patients were included (three males and four females). All patients showed a satisfactory response to dapsone, achieving disease remission in a short period of time with no serious side effects necessitating treatment cessation.

Conclusions

Our findings support that dapsone may have a corticosteroid-sparing effect in the management of AMCBD. Further studies are warranted to confirm our findings.

[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.

Dapsone and sulfones in dermatology: overview and update

In their 60-year history, dapsone and the sulfones have been used as both antibacterial and anti-inflammatory agents. Dapsone has been used successfully to treat a range of dermatologic disorders, most successfully those characterized by abnormal neutrophil and eosinophil accumulation. This article reviews and updates the chemistry, pharmacokinetics, clinical application, mechanism of action, adverse effects, and drug interactions of dapsone and the sulfones in dermatology.

Dapsone and sulfapyridine

Dapsone and sulfapyridine are structurally related compounds with anti-microbial and anti-inflammatory effects. Dapsone remains the most important drug for leprosy and is useful in the prophylaxis of Pneumocystis pneumonia in patients with HIV disease. The medical treatment of choice for dermatitis herpetiformis is dapsone; and sulfapyridine also can be used for those patients who are intolerant of dapsone. Other neutrophilic disorders also may respond to these drugs. Toxic side effects of both dapsone and sulfapyridine are mediated through the hydroxylamine metabolite. These include hemolysis, methemoglobinemia, and agranulocytosis. Careful monitoring for possible adverse reactions includes frequently performing complete blood counts and regular blood chemistry profile determinations.

A century of the synthesis of dapsone: its anti-infective capacity now and then

BACKGROUND

Although dapsone was first synthesized in 1908, a quarter of a century was to pass before it was used in the treatment of bacterial infections. Dapsone was, however, too toxic for humans (because of the excess dosage which was administered at that time) and was thus considered to be of no value in the treatment of common bacterial infections. Since the early 1950s, dapsone has been recognized as being uniquely effective against a number of noninfectious, inflammatory diseases and, today, this is its main indication. Thus, the reason why dapsone was first introduced into medicine, namely the treatment of bacterial infections, has been set aside and its main current applications are the treatment of noninfectious, inflammatory, autoimmune, and bullous diseases.

OBJECTIVE

To study the anti-infective capacity of dapsone against common bacterial infections. As many patients who receive dapsone for the treatment of noninfectious, inflammatory diseases have a concomitant bacterial infection or a superinfection of their skin disease, we thought that, if dapsone proved to be effective against common bacterial infections, it may obviate the need for an additional antimicrobial drug in these patients.

METHODS

Three bacterial ATCC> strains (Streptococcus pyogenes, Staphylococcus aureus, and Escherichia coli) were tested by a macrodilution minimal inhibitory concentration (MIC) test for dapsone. Dapsone concentrations were between 0.06 and 1125 microg/mL.

RESULTS

Even the highest concentration of dapsone of 1125 microg/mL did not inhibit bacterial growth.

CONCLUSIONS

Our results indicate that dapsone has no antibacterial effects whatsoever. Even at very high concentrations, it does not suppress the growth of most susceptible strains of bacteria. The story of dapsone (i.e. the long time that elapsed between its synthesis to its use for the chemotherapy of infectious diseases) will not repeat itself this time.

Sulfapyridine and sulfones decrease glycosaminoglycans viscosity in dermatitis herpetiformis, ulcerative colitis, and pyoderma gangrenosum

Shortly after the introduction of sulfa drugs, sulfapyridine was found to have unique therapeutic properties, unrelated to antibacterial activity. Later, sulfones were found to share the same properties. The disorders initially improved were dermatitis herpetiformis, pyoderma gangrenosum, subcorneal pustular dermatosis, acrodermatitis continua, impetigo herpetiformis and ulcerative colitis. They were also sometimes helpful in many other disorders. They are effective in select disorders characterized by edema followed by granulocytic inflammation or edema followed by vesicle or bullae formation. The sulfones work in low doses in leprosy and their mode of action is not fully understood. Several pieces of experimental information are available. It is proposed that these drugs are entering or influencing the protein moiety of glycosaminoglycans and decreasing tissue viscosity. This decreased tissue viscosity prevents edema and dilution of tissue fluid and decreases acute inflammation and vesicle and bullae formation.