A 30-year-old male presented with 6 months history of multiple, itchy, well defined, discrete as well as confluent, keratotic plaques with hyperpigmented border over chest and back, distributed in a “Christmas tree pattern” [Figure 1a]. The confluence of lesions on trunk exhibited an interesting “arborising pattern” [Figure 1b]. The lesions were covered with adherent thick scales; carpet tack sign was positive. Face and other sun exposed areas were spared. There was no history of photosensitivity. Mucosae, hair, and nails were normal. Routine hematological and biochemical investigations were normal. Antinuclear antibody (ANA) titers were negative. Histopathological examination showed hyperkeratosis, follicular plugging, and epidermal thinning with basal cell degeneration. Dermis exhibited periappendageal and perivascular lymphocytic infiltrates [Figure 2a and b]. The patient is improving with topical corticosteroids and oral hydroxychloroquine.
Figure 1.
(a) Well-defined keratotic plaques with hyperpigmented border over chest and back showing a “Christmas tree pattern”. (b) Confluent plaques in an “arborising pattern”
Figure 2.
(a) HPE showing hyperkeratosis, epidermal thinning, basal cell degeneration with periappendageal and perivascular lymphocytic infiltrates throughout the dermis (H and E; ×4). (b) Epidermal thinning, basal cell degeneration with periappendageal and perivascular lymphocytic infiltrates in dermis (H and E; ×10)
Discoid lupus erythematosus (DLE) is the most frequent manifestation of chronic cutaneous lupus erythematosus (CCLE), which in turn is the commonest form of cutaneous lupus erythematosus. It is often divided into 2 subsets: Localized and disseminated. Lesions of localized DLE are limited to head and neck area, while disseminated DLE affects areas below neck also. The lesions start as an erythematosus macule or papule with a scaly surface and then enlarge peripherally into larger discoid plaques that heal with characteristic atrophic scar and pigmentary changes. Apart from DLE, various other known morphological types of CCLE are hypertrophic or verrucous lupus erythematosus,[1] lupus erythematosus profundus,[2] lupus erythematosus tumidus,[3] and chilblain lupus.[4]
Our patient presented with an unusual morphological pattern in which lesions showed an arborising configuration. Another interesting observation was presence of lesions in a Christmas tree pattern on back which is a photo protected region. Christmas tree distribution of skin lesions has been observed in various skin conditions [Table 1].[5] A thorough search of published English literature using the MeSH terms—arborising CCLE/ramiform CCLE/branching CCLE/Christmas tree pattern in Pubmed, Medline, Cochrane library, Google scholar, Scopus and Embase did not reveal such an unusual description of CCLE. This prompted us to report the case.
Table 1.
Various skin conditions showing Christmas tree pattern
| Skin conditions | Salient features |
|---|---|
| Pityriasis rosea | Multiple, round- to oval-shaped skin lesions predominantly affecting the trunk in a Christmas tree pattern and are usually preceded by a single, significantly larger herald plaque. The eruption usually resolves spontaneously after 6 to 12 weeks |
| Secondary syphilis | Secondary syphilis clinically presents as a symmetrical, non-itchy rash consisting of multiple round to oval, erythematous macules on the trunk, and extremities also covering the palms and soles. The lesions on the patient’s back are distributed in a typical Christmas tree pattern |
| Leser-Trelat sign | The sudden onset of multiple seborrheic keratoses on the trunk, frequently erupting on an inflammatory base. Malignancies associated with Leser-Trélat sign are gastrointestinal adenocarcinomas of the stomach, liver, colon and rectum, and pancreas |
| Exanthematic Kaposi sarcoma | Purple-brownish nodules follow a Christmas tree pattern but may also affect the oral mucosa, gastrointestinal, and respiratory tract |
| Mycosis fungoides | Disease runs slowly through three different stages: patch, plaqu and tumor stage. The macular and plaque-type lesions both tend to follow a Christmas tree pattern |
| Exanthematic psoriasis or guttate psoriasis | Exanthematic psoriasis manifests clinically with multiple, usually itchy, erythematous, round to oval, infiltrated plaques covered by silvery scales in a pattern that may also follow the Langer’s lines |
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The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
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Conflicts of interest
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References
- 1.Kuhn A, Ruzicka T. Classification of cutaneous lupus erythematosus. In: Kuhn A, Lehmann P, Ruzicka T, editors. Cutaneous Lupus Erythematosus. Heidelberg: Springer; 2004. pp. 53–8. [Google Scholar]
- 2.Callen JP. Cutaneous lupus erythematosus: A personal approach to management. Australas J Dermatol. 2006;47:13–27. doi: 10.1111/j.1440-0960.2006.00217.x. [DOI] [PubMed] [Google Scholar]
- 3.Mascaro JM, Herrero C, Hausmann G. Uncommon cutaneous manifestations of lupus erythematosus. Lupus. 1997;6:122–31. doi: 10.1177/096120339700600207. [DOI] [PubMed] [Google Scholar]
- 4.Dutre MS, Beylot C, Beylot J, Pompougnac E, Royer P. Chilblain lupus erythematosus: Report of 15 cases. Dermatology. 1992;184:26–8. doi: 10.1159/000247494. [DOI] [PubMed] [Google Scholar]
- 5.Wollenberg A, Eames T. Skin diseases following a Christmas tree pattern. Clin Dermatol. 2011;29:189–94. doi: 10.1016/j.clindermatol.2010.09.011. [DOI] [PubMed] [Google Scholar]