Acta Dermato-Venereologica, issue 9 97-9CompleteContent

1136 SHORT COMMUNICATION Pemphigus Vulgaris Persistently Localized to the Nose with Local and Systemic Response to Topical Steroids Connie ZHANG 1,2 , Ilana GOLDSCHEIDER 1 , Thomas RUZICKA 1 and Miklós SÁRDY 1 Department of Dermatology and Allergology, Ludwig Maximilian University, Munich, Germany, and 2 Division of Dermatology, Richmond Road Diagnostic and Treatment Centre, University of Calgary, 1820 Richmond Road SW, Calgary, AB, T2T 5C7, Canada. E-mail: cozhang@ ucalgary.ca 1 Accept Jun 8, 2017; Epub ahead of print Jun 9, 2017 Pemphigus vulgaris (PV) is an autoimmune vesiculobul- lous disease characterized by suprabasal acantholysis. It is caused by pathogenic autoantibodies against desmoglein III, sometimes in conjunction with desmoglein I. Because desmoglein III is the major desmosomal component in mucosa, PV almost always involves mucosal surfaces. We present an unusual case of PV with an isolated lesion on the nose, and no mucosal involvement. The literature on this rare presentation is reviewed. The nose, face, and scalp are the commonest sites for localized PV, and this is likely related to both the regional pattern of antigen expression and the effects of ultraviolet radiation. We suggest local topical corticosteroids as first-line therapy based on our experience and the reports in the literature. A 36-year-old previously healthy man, taking no medications, presented to us with a 9-month history of a solitary, 2 × 4 cm, erosive, crusted plaque on the nose (Fig. 1A). He had no other mucocutaneous erosions or blisters. He had not applied any topical medications to the site, and he reported no trauma. The lesion was associated with a sensation of congestion and occasional epistaxis. DISCUSSION CASE REPORT Previously, he had been biopsied at a different clinic with a clinical suspicion of basal cell carcinoma. The pathology showed striking suprabasal acantholysis extending down hair follicles, fitting with PV. At our initial visit, we repeated biopsies including direct im- munofluorescence (DIF). Repeated DIF showed IgG and C3 in a patchy net-like intercellular pattern in the epidermis (Fig. 1B). Overall, the biopsy results were consistent with pemphigus vul- garis, but the patchy IgG pattern was unusual. Desmoglein (Dsg) 3 serum ELISA was positive (89.6 U/ml, normal < 20) but Dsg1 ELISA and indirect immunofluorescence on monkey esophagus were negative. After establishing the diagnosis of localized PV, he started mometasone furoate 1% cream BID to the lesion and had a complete response (Fig. 1C). However, he was unable to taper below 2–3 times weekly applications before a flare would appear, and pimecrolimus 1% cream was not effective. Over two years of ongoing follow-up, his anti-Dsg3 antibody levels trended down to a borderline value of 20.6 U/ml (Fig. 1D), and he continued to have good control with mometasone furoate cream 2–3 times weekly, with no side effects. He did not develop any other pemphigus lesions throughout this period. Furthermore, the sections were examined for expression of Dsg-1 and -3 using anti-human Dsg-1 (Progen #Dsg1-P124) and Dsg-3 (Invitrogen #32-6300) mouse monoclonal antibodies. Dsg1 had patchy staining in the epidermis, whereas anti-Dsg3 antibody did not stain at all (the epidermis of a control section was stained in a honey-comb like pattern with both antibodies). This was an unexpected finding, as the patient only had serum autoantibodies to Dsg3. In PV, pathogenic IgG4 and IgG1 antibodies form against Dsg3; 50% of patients also have antibodies against Dsg1. Autoanti- body binding to desmogleins causes direct inhibition through steric hindrance, as well as inducing signal transduction pathways, both contributing to acantholysis. Clinically, this results in flaccid bullae and erosions, mainly occurring in two patterns: mucosal- dominant and mucocutaneous forms (1). Fig. 1. Clinical and autoimmune features of pemphigus vulgaris (PV) before and after treatment. A: Isolated erosive, crusted, erythematous plaque on the left nose. B: Direct immunofluorescence performed on a perilesional shave biopsy showed epithelial cell surface IgG and C3 staining with patchy intensity. Anti-Dsg3 antibodies did not stain. C: Healing of localized PV after application of topical mometasone furoate 1% cream BID. He maintained control with 2–3 × weekly use. D: Changes of serum Dsg3 titers over time. With topical mometasone furoate only, systemic Dsg3 antibody titers steadily declined to a borderline value, correlating with good disease control. doi: 10.2340/00015555-2725 Acta Derm Venereol 2017; 97: 1136–1137 This is an open access article under the CC BY-NC license. www.medicaljournals.se/acta Journal Compilation © 2017 Acta Dermato-Venereologica.

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