Acta Dermato-Venereologica 99-2CompleteContent | Page 20

218 SHORT COMMUNICATION Blaschkolinear Lichen Planus Pigmentosus in the Setting of Chronic Graft-versus-host Disease Caterina PINZANI 1,2 and Jean-David BOUAZIZ 2 1 Department of Experimental and Clinical Medicine, Institute of Dermatology, University of Udine, Azienda Sanitaria Universitaria Integrata, Udine, Italy, and 2 Dermatology Department and Skin Research Center, Saint Louis Hospital, Paris, France. E-mail: [email protected] Accepted Oct 16, 2018; E-published Oct 17, 2018 Lichen planus pigmentosus (LPP) is a variant of lichen planus characterized by dark-brown macules usually distributed on sun-exposed areas or, rarely, on flexural folds. It is described more often in some ethnic groups from the Indian subcontinent, the Middle East, Far East, and Latin America, especially in people with darker phototypes (1). Blaschkolinear distribution of LPP, probably resulting from a genetic mosaicism, is rarely reported and called Blaschkolinear lichen planus pigmentosus (BLPP) (2). Skin chronic graft-versus-host disease (cGVHD) lesions after allogeneic hematopoietic stem cell transplantation (AHSCT) are characterized by a spectrum ranging from lichenoid to sclerodermoid manifestations (3). CASE REPORT We report here a case of BLPP that occurred in a 34-year-old Mauritian man, who underwent an HLA- identical peripheral blood AHSCT for a stage IIA nodular-sclerosis classical Hodgkin lymphoma. Four months after AHSCT, the patient had cGVHD, namely a bronchiolitis obliterans, a diffuse interstitial pneumonia and a mouth/ocular sicca syndrome. Eight months later, a maculo-papular brownish linear eruption occurred following the Blaschko lines. These cutaneous lesions progressively involved the right leg, the right arm, and the right half-face (Fig. 1). Dermoscopic evaluation showed diffuse brown dots (peppering) over a brown background (Fig. 2), representing dermal pigmentary incontinence resulting from a lichenoid inflammation and dermal-epidermal interface damage (4). Histological analysis showed slight interface dermatitis with marked pigmentary incontinence (Fig. 3). On the basis of the clinical, dermoscopic, and histological presentation a diagnosis of extensive form of BLPP in the context of cGVHD was made. Four months of treatment with once-daily 0.05% betamethasone valerate cream on the body lesions and twice-daily 0.1% tacrolimus induced partial remission. Fig. 1. Erythematous, maculo-papular brownish linear eruption following the Blaschko lines involving the right half-face. A written permission from the patient was given to publish this photo. DISCUSSION A case of a lichen striatus (LS) of the left arm as the only complication after AHSCT (for aplastic anaemia) has been reported previously (5), but to the best of our knowledge this is the first report of BLPP after AHSCT. Cases of LPP in the setting of cGVHD have been repor- doi: 10.2340/00015555-3075 Acta Derm Venereol 2019; 99: 218–219 Fig. 2. Dermoscopic features of the lesion: diffuse brown dots (peppering) over a brown background. This is an open access article under the CC BY-NC license. www.medicaljournals.se/acta Journal Compilation © 2019 Acta Dermato-Venereologica.