Curvilinear violaceous plaques along Blaschko lines (2021)

A 29-year-old man was referred to dermatology with a 5-year history of violaceous crusted plaques with white central regions of ulcerations and overlying erythema that extended in a curvilinear fashion from the right side of his upper back, shoulder, and upper portion of the right arm along the Blaschko lines (Fig 1). He denied any pain, pruritus, or bleeding. His medical and family histories were unremarkable. The laboratory workup, which included a complete blood count, blood urea nitrogen, urinalysis, liver function test, and antinuclear antibodies, was within normal limits. A punch biopsy of the upper portion of the right arm was obtained (Figs 2 and 3).Fig 2View Large Image Figure ViewerDownload Hi-res image Download (PPT)Fig 3View Large Image Figure ViewerDownload Hi-res image Download (PPT) Question 1: What is the best diagnosis?A.Inflammatory linear verrucous epidermal neviB.Linear psoriasisC.Linear cutaneous lupus erythematosus (LCLE)D.Linear lichen planusE.Linear morphea Answers:A.Inflammatory linear verrucous epidermal nevi – Incorrect. Inflammatory linear verrucous epidermal nevi, typically, presents early in childhood with unilaterally located red scaly papules coalescing into a linear plaque and may be accompanied by significant pruritus. Histology demonstrates elongated rete ridges with broad zones of parakeratosis (underlying loss of granular layer) alternating with orthokeratosis. There is no dermal mucin deposition.B.Linear psoriasis – Incorrect. Psoriasis is characterized by sharp demarcated red silvery scaly plaques. Histology reveals elongated rete, parakeratosis with diminished stratum granulosum, accumulation of neutrophils in the stratum corneum, and increase of the capillaries in papillary dermis.C.Linear cutaneous lupus erythematosus (LCLE) – Correct. The dermal mucin deposition is consistent with that of cutaneous lupus erythematosus (CLE). The most common clinical manifestations of CLE are acute CLE, subacute CLE, and discoid lupus erythematosus (DLE). The violaceous nature of the plaques with central crusting in this patient is very reminiscent of DLE. However, LCLE is characterized by a distinct Blaschkoid distribution, and it is less symptomatic than the other forms.1Jin H. Zhang G. Zhou Y. Chang C. Lu Q. Old lines tell new tales: Blaschko linear lupus erythematosis.Autoimmun Rev. 2016; 15: 291-306Crossref PubMed Scopus (18) Google Scholar The laboratory studies such as the antinuclear antibody can be within normal limits.D.Linear lichen planus – Incorrect. Lichen planus presents as polygonal, purple, and intensely pruritic lesions. Histopathology shows a classic “sawtooth” appearance of the dermoepidermal junction, stratum basale degeneration with necrosis, and a band-like lymphocytic infiltrate of the dermoepidermal junction.E.Linear morphea – Although morphea can present along the Blaschko lines, the lesions are generally less violaceous and lack crusting. Histologic characteristics include diffuse interstitial lymphocytic infiltrate, and deeper involvement would show thick hyalinized collagen bundles. Chronic morphea may present histologically with decreased or absent lymphocytic infiltrate, sclerosis, and generalized atrophy. Question 2: Which of the following aspects of LCLE distinguishes it from other forms of CLE?A.Distinct histopathologyB.Younger age of onsetC.Higher progression to systemic lupus erythematosusD.Unique symptom triggersE.High photosensitivity Answers:A.Distinct histopathology – Incorrect. The histopathologic features of dermal mucin deposition and perivascular infiltrates in LCLE are identical to those seen in DLE.1Jin H. Zhang G. Zhou Y. Chang C. Lu Q. Old lines tell new tales: Blaschko linear lupus erythematosis.Autoimmun Rev. 2016; 15: 291-306Crossref PubMed Scopus (18) Google Scholar Some of the additional features seen in both LCLE and DLE include follicular plugging, vacuolar interface dermatitis, and periadnexal infiltrates.1Jin H. Zhang G. Zhou Y. Chang C. Lu Q. Old lines tell new tales: Blaschko linear lupus erythematosis.Autoimmun Rev. 2016; 15: 291-306Crossref PubMed Scopus (18) Google Scholar,2Lim D. Hatami A. Kokta V. Piram M. Linear cutaneous lupus erythematosus in children-report of two cases and review of the literature: a case report.SAGE Open Med Case Rep. 2020; 8https://doi.org/10.1177/2050313X20979206Crossref Scopus (1) Google ScholarB.Younger age of onset – Correct. The mean age of onset is less than 15 years for LCLE,1Jin H. Zhang G. Zhou Y. Chang C. Lu Q. Old lines tell new tales: Blaschko linear lupus erythematosis.Autoimmun Rev. 2016; 15: 291-306Crossref PubMed Scopus (18) Google Scholar whereas the DLE most commonly occurs in the third, fourth, and fifth decades, and the mean age at presentation is about 40 years in subacute forms of lupus erythematosus.C.Higher progression to systemic lupus erythematosus – Incorrect. Progression to systemic lupus erythematosus is rare, with very few cases reported in the medical literature. The association with systemic lupus erythematosus is lower for LCLE (6.5%)1Jin H. Zhang G. Zhou Y. Chang C. Lu Q. Old lines tell new tales: Blaschko linear lupus erythematosis.Autoimmun Rev. 2016; 15: 291-306Crossref PubMed Scopus (18) Google Scholar than that for subacute CLE (18%) and DLE (9.8%-16.7%).3Grönhagen C.M. Fored C.M. Granath F. Nyberg F. Cutaneous lupus erythematosus and the association with systemic lupus erythematosus: a population-based cohort of 1088 patients in Sweden.Br J Dermatol. 2011; 164: 1335-1341Crossref PubMed Scopus (148) Google ScholarD.Unique symptom triggers – Incorrect. Although LCLE presents with some differences from other forms of CLE, such as the age of onset, the epigenetic and multifactorial nature of its pathogenesis may lead to similar triggers such as sunlight and trauma for symptomatic lesions.1Jin H. Zhang G. Zhou Y. Chang C. Lu Q. Old lines tell new tales: Blaschko linear lupus erythematosis.Autoimmun Rev. 2016; 15: 291-306Crossref PubMed Scopus (18) Google Scholar Drugs such as tumor necrosis factor-α inhibitors and heavy metals such as lead that classically trigger both cutaneous and systemic lupus are reasonably expected to trigger LCLE as well.1Jin H. Zhang G. Zhou Y. Chang C. Lu Q. Old lines tell new tales: Blaschko linear lupus erythematosis.Autoimmun Rev. 2016; 15: 291-306Crossref PubMed Scopus (18) Google Scholar,4Zandman-Goddard G. Solomon M. Rosman Z. Peeva E. Shoenfeld Y. Environment and lupus-related diseases.Lupus. 2012; 21: 241-250Crossref PubMed Scopus (84) Google ScholarE.High photosensitivity – Incorrect. Interestingly, LCLE is rarely associated with photosensitivity (11%) when compared with the other cutaneous forms of lupus erythematosus such as DLE (70.9%).1Jin H. Zhang G. Zhou Y. Chang C. Lu Q. Old lines tell new tales: Blaschko linear lupus erythematosis.Autoimmun Rev. 2016; 15: 291-306Crossref PubMed Scopus (18) Google Scholar Question 3: What is the first-line treatment for acute lesions of LCLE?A.Topical corticosteroids or intralesional corticosteroidsB.TacrolimusC.HydroxychloroquineD.Oral retinoidsE.Dapsone Answers:A.Topical corticosteroids – Correct. Topical or intralesional corticosteroids have been the mainstay for LCLE lesions as initial treatment in most cases results in moderate-to-significant improvement of the lesions.5Mao Q.X. Zhang W.L. Wang Q. et al.Linear cutaneous lupus erythematosus/discoid lupus erythematosus in an adult.Postepy Dermatol Alergol. 2017; 34: 177-179Crossref PubMed Scopus (6) Google ScholarB.Tacrolimus – Incorrect. Although topical calcineurin inhibitors like tacrolimus are also commonly reported treatments for LCLE, it is more commonly used as a long-term maintenance therapy to avoid the unwanted side effects of chronic corticosteroid therapy.C.Hydroxychloroquine – Incorrect. Hydroxychloroquine may be effective for long-term therapy in patients for whom topical treatments have failed to reduce symptoms and lesions.D.Oral retinoids – Incorrect. Oral retinoids are considered second-line therapies. The systemic retinoids have teratogenic effects and long-term risk of hypertriglyceridemia and bone abnormalities.E.Dapsone – Incorrect. Systemic dapsone is used in cases of refractory lesions; however, it is a less popular alternative because of its side effects. None disclosed.