Clinical and Dermoscopic Features of the Scalp in 31 Patients with Dermatomyositis

Abstract

Background: Scalp involvement is not directly evaluated in patients with dermatomyositis (DM). Therefore, the exact frequency of scalp dermatomyositis (SDM) and its clinical and trichoscopic characteristics have been poorly described. Objective: The aim of this study was to determine the frequency and clinical and dermoscopic features of SDM in patients diagnosed with DM. Methods: We performed a descriptive prospective, cross-sectional observational study that included all patients diagnosed with DM at a Mexican academic institute over the course of a year. Results: Twenty-four out of 31 patients with DM had scalp involvement at clinical examination, with a prevalence of 77.4%. SDM was clinically characterized by erythema in all cases, scales in 20 (83.3%) patients, nonscarring alopecia in 21 (87.5%) patients, pruritus in 17 (70.8%) patients, and poikiloderma of the scalp in 16 (51.6%) patients. Twenty-eight patients were evaluated by trichoscopy. The most consistent finding was the presence of enlarged capillaries, found in 20 (71.4%) cases, followed by peripilar casts (57.1%) and tufting and interfollicular scales in 14 (50%) cases. Twenty-two patients also had positive nail fold capillaroscopic features similar to those observed by trichoscopy. Limitations: The simple size was limited. Conclusions: Scalp involvement and alopecia are common in patients with DM, and trichoscopy shows features similar to those found at capillaroscopy. Trichoscopy is a very important tool for diagnosis of scalp involvement in patients with DM.

Trichoscopic signs in systemic lupus erythematosus: a comparative study with 109 patients and 305 healthy controls

“…35 Recent studies have reported these findings in systemic autoimmune conditions, described as enlarged and tortuous in dermatomyositis and polymorphic, spider and arborizing with capillary loops in systemic sclerosis. 8,9 From our results, arborizing blood vessels were mostly located interfollicularly and are only alarming if prominent or thick, showing significantly higher odds of having SLE, while thin and sparse arborizing vessel was a frequent finding in normal controls. Scalp is a well-vascularized structure, the mechanism by which SLE causes increase in vessel number and dilatation is largely unknown but may be linked to angiogenesis induced by raised circulating serum angiogenic cytokines.…”

“…In seborrheic dermatitis, the vessels increase in number but are normal‐looking whereas in psoriasis, twisted red loops are classically seen . Recent studies have reported these findings in systemic autoimmune conditions, described as enlarged and tortuous in dermatomyositis and polymorphic, spider and arborizing with capillary loops in systemic sclerosis . From our results, arborizing blood vessels were mostly located interfollicularly and are only alarming if prominent or thick, showing significantly higher odds of having SLE, while thin and sparse arborizing vessel was a frequent finding in normal controls.…”

“…Valuable results had been reported in patients with systemic sclerosis and dermatomyositis. 8,9 Although hair and scalp involvement in SLE is fairly common, the trichoscopic features of SLE patients have been largely under-recognized. Moreover, the main focus has been on lesions of chronic cutaneous lupus erythematosus (CCLE), including scalp DLE and linear lupus panniculitis of the scalp, which are only present in a small subset of SLE patients.…”

“…Currently, there has been increasing interests in trichoscopic features of autoimmune diseases. Valuable results had been reported in patients with systemic sclerosis and dermatomyositis . Although hair and scalp involvement in SLE is fairly common, the trichoscopic features of SLE patients have been largely under‐recognized.…”

An Undetected Case of Tinea Capitis in an Elderly Woman Affected by Dermatomyositis: How Trichoscopy Can Guide to the Right Diagnosis

“…Clinically it is characterized by atrophic, erythematous, and scaly plaques, frequently accompanied by diffuse nonscarring alopecia [2]. Major trichoscopic features in scalp DM are enlarged capillaries and peripilar casts, both present in our patient [6]. In addition, trichoscop ic evaluation showed characteristic figures of “comma hairs,” “zigzag hairs,” and “pigtail hairs,” which suggested concomitant TC [3, 4].…”