DP14 Going against the grain: eosinophilic dermatosis presenting as erythema gyratum repens

Abstract

Abstract Erythema gyratum repens (EGR) is a rare, paraneoplastic rash with a characteristic woodgrain appearance. It is heavily associated with malignancies, including lung, oesophageal and breast cancers. However, other conditions can mimic EGR, including leucocytoclastic vasculitis, immunobullous and papulosquamous conditions. We report an unusual presentation of eosinophilic dermatosis with an EGR-like pattern, not associated with malignancy. A 67-year-old woman presented with a 2-week history of a pruritic eruption on her legs. It initially started with three small circular erythematous macules on the right leg and one on the left leg. Over the course of a few days, the three macules evolved into large concentric annular patches simulating woodgrain, which raised the clinical suspicion of EGR. After a week, the patches began to blister with accentuation of some of the blisters on the edge of the annular patches. She denied any previous history of skin problems or changes in medication and was otherwise well with no systemic symptoms, including fever. In view of the almost 70% chance of an underlying malignancy, she was thoroughly investigated. Her full blood count, eosinophil count, liver function test, renal profile and serum C3 and C4 were normal. Skin basement membrane/desmosome antibodies and Borrelia burgdorferi IgG and IgM antibodies were also negative. Histology revealed prominent epidermal spongiosis with some corneal and intraepidermal vesicles that were cell-poor and contained only red blood cells. The underlying dermis showed prominent papillary dermal oedema with a brisk interstitial and superficial/deep perivascular mixed inflammatory infiltrate containing numerous eosinophils but no obvious flame figures. There was also eosinophil infiltration into the underlying subcutaneous fat. Direct immunofluorescence was negative. The histological pattern was that of an eosinophil-rich dermatitis with vesiculation; the history and morphology of the eruption were not compatible with bullous insect bites. An eosinophilic dermatosis such as eosinophilic cellulitis presenting with an EGR-like pattern was considered to be the most likely possibility for her presentation. Computed tomography of the neck, thorax, abdomen and pelvis, bidirectional endoscopy and mammography revealed no malignancies. She was treated with prednisolone 30 mg daily for 10 days with Elocon® ointment, and the eruption improved remarkably leaving postinflammatory colour changes that subsequently resolved. We would like to raise the awareness that an EGR-like pattern can be found in several other dermatoses, including eosinophilic dermatosis, and woodgrain pattern is not always equivalent to EGR or a high risk of associated malignancies (Table 1).Table 1Erythema gyratum repens-like dermatosesLeucocytoclastic vasculitisImmunobullousPapulosquamousBullous pemphigoidPsoriasisEpidermolysis bullosa acquisitaPityriasis rubra pilarisLinear IgA dermatoses