Erythema elevatum diutinum in association with dermatitis herpetiformis

Abstract

Erythema elevatum diutinum (EED) is a rare skin disease that initially presents as leucocytoclastic vasculitis and later resolves with fibrosis. Dermatitis herpetiformis is an autoimmune blistering disease characterized by granular deposits of immunoglobulin A (IgA) in dermal papillae. We report a rare association of these two disorders.

INTRODUCTION

EED is a localized, low-grade form of leukocytoclastic vasculitis of unknown pathogenesis characterized by persistent, symmetrical, red-purple papules, nodules, and plaques affecting the extensor surfaces of the extremities, the ears, trunk and buttocks. Dermatitis herpetiformis is an autoimmune blistering disease characterized by granular deposits of immunoglobulin A (IgA) in dermal papillae. The common link between these two disorders is the deposition of Ig A antibodies, underlying gluten sensitivity in both, their association with celiac disease and response to treatment with dapsone. This is only the second case regarding the coexistence of these two disorders.[¹]

CASE REPORT

A 50-year-old male presented with firm skin-colored and erythematous nodules over the knuckles, elbows, buttocks, knees, and lower legs which gradually increased in size in since 3 years duration [Figure 1]. Complete blood picture, liver function tests, urine routine, blood sugar were within normal limits. Biopsy of the nodules of the knuckles showed focal parakeratosis and mild spongiosis in the epidermis, perivascular neutrophilic infiltrate in the dermis, neutrophils in the vessel wall and leukocytoclasia [Figure 2]. Immunofluorescence showed linear IgA deposits in the basement membrane zone and weak granular perivascular C3 and fibrinogen deposits [Figure 3]. Four years ago itchy vesicles over the back and arms were detected in the patient. Biopsy of the vesicular lesions were consistent with dermatitis herpetiformis [Figure 4]. He was administered dapsone which leads to disappearance of lesions with recurrence after stopping treatment. With the clinical presentation, biopsy and immunofluorescence results, a diagnosis of erythema elevatum diutinum on a background of dermatitis herpetiformis was made.

Figure 1: Skin-colored nodules over the knuckles

Figure 2: Neutrophilic vasculitis with leucocytoclasia (H and E, ×400)

Figure 3: Linear IgA deposits in the basement membrane zone

Figure 4: Dermal papillary microabscess (H and E, ×400)

DISCUSSION

Erythema elevatum diutinum (EED) is a rare cutaneous condition that initially presents as leukocytoclastic vasculitis (LCCV) of the skin and later resolves with fibrosis clinically characterized by persistent red-purple to yellow papules, plaques, and nodules. The symmetrical lesions typically affect the acral surfaces of the body, especially the extensor surfaces of the hands, but other areas such as the buttocks may also be involved.[²] Antecedent bacterial infections, collagen vascular diseases, myeloproliferative diseases, human immunodeficiency virus infection, cryoglobulinemia, Wegener granulomatosis, Crohn disease, systemic fungal diseases, IgA paraproteinemia, and other associations have been reported.[³⁴] Histopathologically, EED initially presents as a leukocytoclastic vasculitis (LCCV) with polymorphonuclear neutrophils, extravasated red cells, nuclear dust, and fibrin deposits in the walls of the small arterioles. Most of the lesions eventually resolve with fibrosis. Direct immunofluorescence usually demonstrates IgG and C3 deposits within vessels in the upper dermis.

Dermatitis herpetiformis (DH) is characterized by chronic, intensely pruritic, polymorphic, vesicles usually appearing on elbows, knees, buttocks, and scalp associated with gluten-sensitive enteropathy There are granular IgA deposits in the dermal papillae by the direct immunofluorescence in the perilesional skin of patients with dermatitis herpetiformis.[⁵]

The close association of IgA with erythema elevatum diutinum and dermatitis herpetiformis is well known. Because of the association with IgA, the presence of erythema elevatum diutinum in a patient with chronic dermatitis herpetiformis is not surprising. The IgA in the skin may be an epiphenomenon or may represent deposition in the skin along with other immune complexes.^{[ 1]}

Aftab MN et al.[¹] have reported a case of erythema elevatum diutinum arising in the setting of dermatitis herpetiformis. They concluded that IgA immune complexes within the basement membrane zone region may trigger a cascade that eventuates into a blister or the formation of the chronic vasculitis of erythema elevatum diutinum.

We report this case because of the rare co incidence of these two disorders.