Dermatology: Practical and Conceptual Research Letter | Dermatol Pract Concept. 2023;13(3):e2023183 1 Necrobiosis-Lipoidica-Like Skin Lesions in a Patient with Non-Systemic Sarcoidosis Pietro Bearzi1, Francesca Trunfio1, Rosa Coppola2, Damiano Currado1, Claudio Conforti3, Salvatore Zanframundo2, Lorenzo Nibid4, Michele Donati4, Vincenzo Panasiti2, Luca Navarini1,5, Roberto Giacomelli1,5 1 Rheumatology, Immunology, and Clinical Medicine Unit, Department of Medicine, Campus Bio-Medico di Roma University, Rome, Italy 2 Department of Reconstructive and Aesthetic Plastic Surgery, University Hospital Fondazione Campus Bio-Medico di Roma, Rome, Italy 3 Dermatology Clinic, Maggiore Hospital of Trieste, Trieste, Italy 4 Department of Pathology, University Hospital Fondazione Campus Bio-Medico di Roma, Rome, Italy 5 Immunohematology Unit, University Hospital Fondazione Campus Bio-Medico di Roma, Rome, Italy Key words: sarcoidosis, necrobiosis lipoidica, granulomatous skin disease, dermoscopy, clinicopathological correlations Citation: Bearzi P, Trunfio F, Coppola R, et al. Necrobiosis-Lipoidica-Like Skin Lesions in a Patient with Non-Systemic Sarcoidosis. Dermatol Pract Concept. 2023;13(3):e2023183. DOI: https://doi.org/10.5826/dpc.1303a183 Accepted: February 8, 2023; Published: July 2023 Copyright: ©2023 Bearzi et al. This is an open-access article distributed under the terms of the Creative Commons Attribution- NonCommercial License (BY-NC-4.0), https://creativecommons.org/licenses/by-nc/4.0/, which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original authors and source are credited. Funding: None. Competing interests: None. Authorship: All authors have contributed significantly to this publication. Corresponding author: Pietro Bearzi, MD, Department of Allergology, Immunology and Rheumatology, University Hospital Fondazione Campus Bio-Medico di Roma, via Alvaro del Portillo 21, 00128 Rome, Italy. E-mail: pietro.bearzi@unicampus.it Introduction Ulcerative-atrophic cutaneous sarcoidosis (CuS) represent a rare form of sarcoidosis, showing different clinicopatholog- ical variants: morpheaform, necrobiosis lipoidica (NL)-like and lipodermatosclerosis-like [1]. NL-like CuS is character- ized by round, depressed skin lesions with hypopigmenta- tion and telangiectasias, showing histopathological features of both NL and CuS [1]. Only NL has been associated to diabetic microangiopathy [2]. Case Presentation A non-diabetic-63-year-old Caucasian female came to our at- tention for a one-year history of painful violaceous erythem- atous plaques on the left forearm and elbow with ipsilateral elbow joint tenderness. Six months earlier she underwent left elbow MRI and olecranic bone biopsy, revealing a chronic inflammatory process with focal epithelioid non-necrotizing granulomas and negative cultural test. Furthermore, the pa- tient was taking levothyroxine for Hashimoto thyroiditis. At physical examination the patient presented multi- ple red-purple atrophic plaques of the left elbow without joint tenderness (Figure 1A). Upon dermoscopy, the lesions showed a heterogeneous orange-pinkish background with white structureless areas and follicular keratotic plugs. The lesions vascular pattern was characterized by linear irregular, arborizing vessels (Figure 1 B and C) and peripheral hairpin vessels (Figure 1C). Skin punch-biopsy revealed numerous non-necrotizing epithelioid granulomas and Langhans giant cells, located in the superficial and deep dermis. Granulomas were 2 Research Letter | Dermatol Pract Concept. 2023;13(3):e2023183 surrounded by intense lymphocytic infiltrate with numerous plasma cells. Moreover, palisading histocytes around areas of necrobiosis were also prominent (Figure 1D). Other causative agents for granuloma formation (ie foreign body, microorganisms) were clinically excluded and supported by negative Periodic Acid-Schiff (PAS) and Ziehl-Neelsen spe- cial stains. In conclusion the clinical, dermoscopic and histo- pathological findings plus the negative systemic assessment (ie thoracic-CT, pulmonary function test, electrocardiogram, serum ACE, CRP, VES), supported the diagnosis of localized NL-like CuS with previous ipsilateral bone sarcoidosis. Topi- cal betamethasone cream applied twice daily was prescribed. At four-months follow up the lesions appeared smaller, less infiltrated with reduction of referred pain and negative blood tests. Conclusions Ulcerative/atrophic CuS and NL are granulomatous-skin disorders of unknown etiology, sharing similar clinicopath- ological features [2,3]. As for our case, NL-like CuS affects middle-aged females, without history of diabetes/glucose in- tolerance [2,3]. In our patient, the lesions were located at the upper limbs, while NL and NL-like CuS affect mostly the lower limbs [3]. The coexistence of CuS with NL in the same lesion underlie the possibility that these represent different stages of the same granulomatous skin disease [3].3 Dermoscopy is useful for differential diagnosis of granulomatous skin diseases [4]. NL presents heteroge- neous orange-pinkish background and comma/serpentine/ arborizing vessels [5]. On the other hand, CuS presents a pink homogeneous background, white structureless areas and fine white scales with disease stage-dependent vascular patterns [4,5]. Our NL-like CuS case showed mixed der- moscopic findings: background color compatible with NL, white structureless areas typical of CuS, and arborizing plus peripheral hairpin vessels compatible with both CuS and NL [4,5]. To the best of our knowledge, this is the first case of upper limb NL-like CuS associated to localized sarcoidosis. This CuS variant is associated to systemic sarcoidosis; thus, com- plete staging and strict follow up is crucial for treatment.2 Figure 1. (A) multiple red-purple ulcerated plaques of the left elbow, associated with joint pain. (B,C) Dermoscopy showed a hetero- geneous orange, pinkish, reddish background with white structureless areas and aspecific vascular pattern: linear irregular, arborizing vessels plus peripheral haipin vessels. (D) Tissue slide showing non-necrotizing epithelioid granulomas (arrow) with Langhans giant cells (arrowhead) surrounded by lymphocytes. Note the areas of necrobiosis (asterisk) (H&E stain, 5x, scale bar: 500 µm). Research Letter | Dermatol Pract Concept. 2023;13(3):e2023183 3 First line treatment for localized NL-like CuS is based on topical/intralesional corticosteroids, while oral prednisone should be considered for recalcitrant/systemic disease [2,4]. References 1. Karadağ AS, Parish LC. Sarcoidosis: A great imitator. Clin Dermatol. 2019;37(3):240-254. DOI: 10.1016/j.clindermatol .2019.01.005. PMID: 31178106. 2. Araghi F, Tabary M, Rakhshan A, Dadkhahfar S, Robati RM. Necrobiosis lipoidica-like lesions in a nondiabetic patient with systemic sarcoidosis: A case report and review of the literature. Clin Case Rep. 2020;8(12):2782-2786. DOI: 10.1002/ccr3.3281. PMID: 33363822. PMCID: PMC7752443. 3. Chandan N, Jerdan K, Tsoukas M, Braniecki M. Sarcoidosis With Cutaneous Manifestations of Necrobiosis Lipoidica. Am J Dermatopathol. 2020;42(4):308-311. DOI: 10.1097 /DAD.0000000000001488. PMID: 31313692. 4. Ramadan S, Hossam D, Saleh MA. Dermoscopy could be use- ful in differentiating sarcoidosis from necrobiotic granulomas even after treatment with systemic steroids. Dermatol Pract Concept. 2016;6(3):17-22. DOI: 10.5826/dpc.0603a05. PMID: 27648379. PMCID: PMC5006548. 5. Lallas A, Zaballos P, Zalaudek I, et al. Dermoscopic patterns of granuloma annulare and necrobiosis lipoidica. Clin Exp Der- matol. 2013;38(4):425-427. DOI: 10.1111/ced.12126. PMID: 23495727.