Acta Dermato-Venereologica 99-13CompleteContent | Page 26

1295 SHORT COMMUNICATION Vasculitis Mimicking Pseudo Erysipelas in Systemic Lupus Erythematosus Morgane WEISS 1 , Marie-Dominique VIGNON 2 , Clémence LEPELLETIER 1 , Lou MACAUX 1 , Marie JACHIET 1 , Adèle DE MASSON 1 , Martine BAGOT 1 and Jean-David BOUAZIZ 1 * Dermatology Department, and 2 Anatomopathology Department, Saint-Louis Hospital, 1 avenue Claude Vellefaux, 75745 Paris cedex 10, France. *E-mail: [email protected] 1 Accepted Oct 3, 2019; E-published Oct 3, 2019 Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease characterized by heterogeneous clinical and serological manifestations that may affect any organ (1). Cutaneous lupus erythematosus (CLE) is an autoimmune disorder occurring independently of or as a manifestation of SLE, including acute cutaneous lupus erythematosus, subacute cutaneous lupus, and chronic cutaneous lupus erythematosus (discoid lupus erythematosus, lupus erythematosus profundus, chilblain cutaneous lupus, and lupus tumidus) (2). The prevalence of vasculitis in SLE is reported to be between 11% and 36%, with a diverse clinical spectrum due to inflam- matory involvement of vessels of all sizes (3). Pseudo- erysipelas (PE) is a cutaneous manifestation seen in periodic fever syndromes, presenting as erythematous and swollen extremities. We report the case of a man who developed a PE concomitant with an acute SLE flare. CASE REPORT A 42-year-old Guyanese man, diagnosed 12 years ago with cutaneous, articular and cardiac SLE, who was not currently undergoing treatment, presented with a 38.5°C fever and symmetrical, painful swelling and thickening of both legs (Fig. 1A), associated with infil- trated ery­thematosus annular lesions of the trunk, back and face, and atrophic hyperpigmented keratotic lesions of the face, ears and elbows. Routine biological tests re- Fig. 1. Symmetrical, painful, swelling and thickening of both legs (A). Complete remission after steroid treatment (B). vealed anaemia (10.3 g/dl), neutropenia (1.01 × 10 9 G/l), lympho­penia (1.05  ×10 9 G/l), and negative CRP (3 mg/l, normal range < 5 mg/l). Immunological tests revealed positivity for anti-nuclear antibodies (1/1,600), anti-RNP, anti-Sm, anti-SSA, and anti-P ribosomes. The C3 and C4 complement levels were normal. Urine tests revea- led proteinuria (1.3 g/day). A deep biopsy taken from the left leg showed a dermo-hypodermal lymphocytic infiltrate. It involved and surrounded the walls of small and medium-sized vessels with fibrin deposits in some of them (Fig. 2). Two other biopsies taken from the back and the left arm showed dermal lymphocytic infiltrates with interface dermatitis and mucin deposits in favour of lupus erythematosus. Renal biopsy showed class II and V lupus nephritis. Treatment with hydroxychloroquine and 3-day intravenous injections of 500 mg of methyl- prednisolone was started, followed by oral prednisone 1 mg/kg/day for one month, which was associated with the complete remission of the skin lesions and systemic symptoms (Fig. 1B). Methotrexate (20 mg) once a week was started as a background treatment for SLE. Progres- sive tapering of steroids was performed with favourable clinical evolution during the 6-month follow-up. DISCUSSION The originality of this case comes from the associa- tion of PE and the SLE flare. This is, to the best of our Fig. 2. Dermo-hypodermal lymphocytic infiltrate surrounding the walls of small and medium-sized vessels with fibrin deposits in some of them. This is an open access article under the CC BY-NC license. www.medicaljournals.se/acta Journal Compilation © 2019 Acta Dermato-Venereologica. doi: 10.2340/00015555-3334 Acta Derm Venereol 2019; 99: 1295–1296