Dermatology: Practical and Conceptual Letter to the Editor | Dermatol Pract Concept. 2024;14(1):e2024002 1 Spotted Lunula in Alopecia Areata: Clinical and Onychoscopic Features of an Unusual Sign Michela Starace1,2 , Stephano Cedirian1,2, Carlotta Gurioli1,2, Marco Adriano Chessa1,2, Bianca Maria Piraccini1,2, Iria Neri1,2 1 Dermatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Policlinico S. Orsola-Malpighi, Bologna, Italy 2 Department of Medical and Surgical Sciences, Alma Mater Studiorum University of Bologna, Italy Citation: Starace M, Cedirian S, Gurioli C, Chessa MA, Piraccini BM, Neri I. Spotted Lunula in Alopecia Areata: Clinical and Onychoscopic Features of an Unusual Sign. Dermatol Pract Concept. 2024;14(1):e2024002. DOI: https://doi.org/10.5826/dpc.1401a2 Accepted: July 23, 2023; Published: January 2024 Copyright: ©2024 Starace 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: Bianca Maria Piraccini MD, PhD, Via. G. Massarenti, 9 – 40138 – Bologna (Italy). Tel: +39 0512143848 E-mail: biancamaria.piraccini@unibo.it Dear Editor, Alopecia areata (AA) is an autoimmune disorder char- acterized by non-scarring alopecia that can affect any hair- bearing area, although the scalp is the most common site. AA can also involve the nail apparatus. The most frequent nail manifestation associated with AA are nail pitting and trachy- onychia; however, other signs can also aid in its diagnosis, such as punctate leukonychia or Beau lines [1,2]. In this ar- ticle, we would like to highlight another non-diagnostic but characteristic nail sign of AA, the spotted lunula (SL). SL is a sign that, upon clinical examination, presents as small, circular, reddish areas that do not disappear under vit- ropressure. Its borders are well-defined and regularly distrib- uted throughout the  lunula. On onychoscopy, dilation and tortuosity of the distal matrix vessels can be observed, re- flecting an involvement of the papillary dermis (Figure 1). SL is a sign of nail matrix inflammation associated with various diseases, including AA and nail psoriasis [3]. Nail involvement in AA is not uncommon, although it is not pathognomonic, and according to the literature, it can affect anywhere from 7% to 66% of patients, especially due to matrix inflammation [1,2]. It is more commonly observed in severe forms of AA, such as AA Totalis or AA Universalis, as well as in children [4]. SL was initially described by Shelley in 1980 [5]. A to- tal reddish involvement of the lunula, due to arteriolar vas- cularization, has also been reported [6]. Notably, SL is not commonly referenced in major dermatology textbooks [7], and in large population studies, such as the one published by Sharma et al with 1000 patients [8]. To the best of our knowledge, SL has only been reported in two studies: Tosti et al documented this finding in a series of 126 pediatric cases, reporting 6 affected patients, and Roest et a. reported a prev- alence of 13% in a case-control study [9,10]. Regarding prognosis and treatment, spontaneous remis- sion is often observed in patients with AA, typically with hair regrowth. In cases of isolated nail involvement, some patients may require treatment, which is mainly based on personal clinical experience and small case series. Topical therapy with corticosteroids, such as mometasone 0.1% ointment or clobetasol 8% nail lacquer, is the first choice. For resistant forms, the same systemic treatment regimens used for scalp involvement can be considered [1]. 2 Letter to the Editor | Dermatol Pract Concept. 2024;14(1):e2024002 In conclusion, SL is an underappreciated finding in suspected AA without obvious manifestations, and ony- choscopy once again proves to be a crucial non-invasive di- agnostic tool. References 1. Chelidze K, Lipner SR. Nail changes in alopecia areata: an up- date and review. Int J Dermatol. 2018;57(7):776–783. DOI: 10.1111/ijd.13866. PMID: 29318582. 2. Starace M, Alessandrini A, Bruni F, Piraccini BM. Trachyonychia: a retrospective study of 122 patients in a period of 30  years. JEur Acad Dermatol Venereol. 2020;34(4):880–884. St DOI: 10.1111/jdv.16186. PMID: 31923322. 3. Baran R. Comment reconnaître et traiter un psoriasis unguéal [How to diagnose and treat psoriasis of the nails]. Presse Med. 2014;43(11):1251-1259. DOI: 10.1016/j.lpm.2014.06.011. PMID: 25443636. 4. Kasumagic-Halilovic E, Prohic A. Nail changes in alopecia areata: frequency and clinical presentation. J Eur Acad Der- matol Venereol. 2009;23(2):240-241. DOI: 10.1111/j.1468- 3083.2008.02830.x. PMID: 18540984. 5. Shelley WB. The spotted lunula: A neglected nail sign associated with alopecia areata. J Am Acad Dermatol. 1980;2(5):385-387. DOI: 10.1016/s0190-9622(80)80360-4. PMID: 7381066. 6. Morrissey KA, Rubin AI. Histopathology of the red lunula: New histologic features and clinical correlations of a rare type of erythronychia. J Cutan Pathol. 2013;40(11):972–975. DOI: 10.1111/cup.12218. PMID: 24102674. 7. Sperling L, Sinclair R, Shabrawi-Caelen L. Alopecias. In: Bolognia J, Lorizzo J, Schaffer J, editors. Dermatology. 4ed. Elsevier; 2018:1093–1114. 8. Sharma VK, Dawn G, Muralidhar S, Kumar B. Nail changes in 1000 Indian patients with alopecia areata. J Eur Acad Der- matol Venereol. 1998;10(2):189–190. SDOI: 10.1111/j.1468- 3083.1998.tb00727.x. PMID: 9553924. 9. Tosti A, Morelli R, Bardazzi F, Peluso AM. Prevalence of Nail Abnormalities in Children With Alopecia Areata. Pediatr Der- matol. 1994;11(2):112–115. DOI: 10.1111/j.1525-1470.1994 .tb00562.x. PMID: 8041648. 10. Roest YBM, Van Middendorp H, Evers AWM, Van De Kerkhof PCM, Pasch MC. Nail involvement in alopecia areata: A questionnaire-based survey on clinical signs, impact on qual- ity of life and review of the literature. Acta Derm Venereol. 2018;98(2):212–217. DOI: 10.2340/00015555-2810. PMID: 28967977. Figure 1. (A,B) Clinical (A) and onychoscopic (B) image of the spotted lunula that appears as a small, circular, reddish area with visible dilation and tortuosity of the distal matrix vessels.