Isolated linear blaschkoid psoriasis

Linear Psoriasis in a Pediatric Patient Successfully Treated With Ixekizumab

Linear psoriasis is a rare clinical presentation of psoriasis characterized by erythematous scaly plaques distributed along Blaschko's lines. We describe an 8-year-old male with a linear Blaschkoid plaque in which biopsy findings and clinical history were consistent with linear psoriasis. The lesion showed only mild improvement with topical steroid therapy but exhibited significant clearance with the biologic agent ixekizumab, an IL-17A inhibitor. With limited supporting literature regarding management, this case report illustrates the clinical manifestation, diagnosis, and an effective management strategy for linear psoriasis in a pediatric patient.

Clinical Characteristics and Therapeutic Aspects of Blaschko Linear Psoriasis

INTRODUCTION

Blaschko linear psoriasis (BLP) is characterized by the linear distribution of psoriatic skin lesions along the Blaschko lines. BLP can be divided into type I and type II, mainly on the basis of clinical manifestations. BLP can easily cause psychological burdens in patients and clinical confusion for physicians. Here, we summarize clinical cases to provide a better understanding of BLP.

METHODS

The subjects included patients with BLP who visited our dermatology departments and those reported in the literature obtained from the PubMed and Wanfang databases. Quantitative data were presented as means ± SD (standard deviation), and qualitative data were represented by the frequency. Student's t test was employed to compare means, whereas chi-square tests were used for analyzing qualitative data.

RESULTS

A total of 74 patients with BLP (5 our patients, 69 from literature) were included, with 61 type I and 13 type II patients. We summarize BLP's characteristics as follows: (1) More frequent in male individuals, especially in type II; (2) Earlier onset than classical psoriasis; (3) Mainly distributed unilaterally, and no preference for left or right site; (4) Asymptomatic or slight pruritus; (5) Mostly negative family history of psoriasis; (6) Possible involvement of the nails/scalp (mainly for type II); (7) Possible exogenous triggering or aggravation factors; (8) Possible concomitant classical plaque or guttate psoriasis lesions, especially in type II; (9) Conforming to histopathology features of classical psoriasis; (10) Relatively favorable response to antipsoriatic treatment, although poor for superimposed areas in type II.

CONCLUSION

This study analyzed the clinical characteristics and therapeutic aspects of BLP. Compared with published studies, we have new findings, such as gender bias. Besides traditional antipsoriatic treatment, a personalized selection of biologics may also be a promising choice. Dermatologists should recognize and understand the significance of this disease, and provide patients with appropriate psychological counseling and clinical treatments.

Inflammatory linear verrucous epidermal nevus associated with erosive monoarthritis

Inflammatory linear verrucous epidermal nevus and linear psoriasis are different entities with clinical and histopathologic similarities. Isolated reports of inflammatory linear verrucous epidermal nevus with concomitant psoriasis or a positive family history of psoriasis have been described, and the possibility that inflammatory linear verrucous epidermal nevus may be a mosaic form of cutaneous psoriasis has been postulated. We report a 17-year-old boy with a congenital, linear, erythematous, keratotic plaque on the dorsum of the fifth finger of the left hand with ipsilateral nail dystrophy. Histopathologic examination showed epidermal hyperplasia with alternating orthokeratosis and parakeratosis. During follow-up, he developed erosive monoarthritis of the distal interphalangeal joint. This case seems to confirm the association between inflammatory linear verrucous epidermal nevus and arthritis and supports a possible relationship between inflammatory linear verrucous epidermal nevus and psoriasis.