The Successful Treatment of a Case of Linear Psoriasis with Ixekizumab

Ustekinumab is effective in the treatment of linear psoriasis: a case report and literature review

Linear psoriasis is a rare type of psoriasis that usually presents as scaly papules and plaques unilaterally distributed along the Blaschko line. Currently, the pathogenesis of linear psoriasis is not fully understood, and genetic mosaicism may be one of the explanations. As linear psoriasis is less responsive to treatment than psoriasis vulgaris, there is no consensus on treatment guidelines specifically for this disease, and the efficacy of ustekinumab in treating this category has not been reported. In this article, we present a case of effective treatment of linear psoriasis with ustekinumab and review the relevant literature, hoping to help clinicians better understand and treat this disease.

Successful Treatment of Linear Psoriasis With the IL-17a-Antagonist Ixekizumab: A Case Report

Linear psoriasis (LP) represents a rare variant of psoriasis. The clinical presentation includes erythematous plaques distributed along the Blaschko lines, reflecting the presence of embryological mosaicism. The clinical and histopathological features of this condition show many similarities with inflammatory linear verrucous epidermal nevus (ILVEN), which presents a challenge in differential diagnosis. Currently there is no disease-specific treatment guidelines causing a challenge in the therapeutic management. In this case report we describe a 28-year-old patient with LP. Clinically characterized by persistent, psoriasiform lesions that proved refractory to treatment with topical corticosteroids, vitamin D analogs, and systemic dimethyl fumarate. The histopathological findings showed psoriasiform epidermal hyperplasia with alternating ortho- and parakeratosis, subepidermal capillary dilatation, and perivascular lymphocytic infiltrates, confirming the diagnosis. Ixekizumab, a IL-17A antagonist, was administered leading to a rapid and significant reduction in disease severity within the first 16 weeks. The Psoriasis Area and Severity Index (PASI) decreased from 12.5 to 1.0 and as well as the Dermatology Life Quality Index (DLQI) improved to 1. Both scores prove significant improvement in quality of life and clinical severity. This case report shows the importance of histological confirmation in differentiating LP from clinically similar appearing diseases like ILVEN and highlights the potential therapeutic benefit of IL-17 blockade in LP. In addition, the findings emphasize the need for systematic studies to develop evidence-based treatment strategies for this rare psoriasis phenotype.

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.

Successful Treatment of Inflammatory Linear Verrucous Epidermal Nevus with Concomitant Psoriasis Using Etanercept

Linear psoriasis is a rare form of the disease characterized by the linear distribution of lesions involving dermatome or along Blaschko's lines. Clinically, it may resemble inflammatory linear verrucous epidermal nevus; a combination of history, skin examination, and histopathology are required to ensure correct diagnosis and appropriate therapy. This paper describes a case of a 23-year-old male presenting with unilateral erythematous scaly plaques arranged in a linear path on the left leg. Etanercept was initiated after poor response to adalimumab. Improvement of his psoriasis was noted, with PASI 75 reduction after 24 weeks of treatment. Clinical studies have shown excellent efficacy of etanercept, and our patient well tolerated treatment with etanercept for 52 weeks without any adverse effects.