Background: Biologics have been increasingly used in the treatment of severe psoriasis. However, evidence regarding the results of tuberculosis (TB) screening and risk of latent tuberculosis infection (LTBI) during treatment with biologics is conflicting.
Objective: We aimed to assess the prevalence of LTBI in patients with severe psoriasis who were treated with biologics (anti-tumor necrosis factor-α, interleukin [IL]-12/23, IL-17, and IL-23) and to evaluate the rate of conversion of interferon-gamma release assay (IGRA) during treatment with biologics at a single medical center.
Methods: We retrospectively reviewed the medical records of patients with severe psoriasis who were treated with biologics (n=118) and had results for ≥2 IGRA (n=76). Data including demographics, age, sex, previous therapy for psoriasis, and type of ongoing treatment were collected for each patient.
Results: Among the 118 patients included in the study, 30 (25.4%) were diagnosed with LTBI before the initiation of biologics, 25 (83.3%) were male, and only five patients were aged below 40 years. After treatment with biologics for an average duration of 2.4 years, there was no active tuberculosis infection in 76 patients, but eight patients (10.5%) showed positive conversion of IGRA.
Conclusion: Altogether, 10.5% of the patients with psoriasis who were undergoing treatment with biologics exhibited IGRA conversion. Periodic follow-up is crucial to avoid severe infectious complications during prolonged use of these agents, especially in patients with risk factors for tuberculosis or in patients aged above 50 years. (Korean J Dermatol 2022;60(10):631∼639)

Background: Pathogenesis of psoriasis is related to dysregulated keratinocyte function and immune responses. Genetic background is one of the most important factors in disease pathogenesis. However, psoriasis-associated genes have not yet been fully identified. Activating transcription factor 3 (ATF3) is a member of the cyclic adenosine monophosphate responsive element-binding protein family of transcription factors, which may regulate epidermal keratinocytes.
Objective: We aimed to evaluate the effects of ATF3 on inflammation and differentiation of keratinocytes.
Methods: We evaluated the expression of ATF3 in polyinosinic:polycytidylic acid (poly[I:C])-treated keratinocytes. Subsequently, we compared ATF3 levels in psoriatic and normal skin using immunohistochemical staining. To illustrate the role of ATF3, we generated ATF3-overexpressing keratinocytes and ATF3-knockdown keratinocytes using a recombinant adenovirus. We investigated inflammation and differentiation of keratinocytes by measuring the mRNA levels of inflammatory cytokines and differentiation markers.
Results: Treatment of keratinocytes with poly(I:C) increased ATF3 expression in a time-dependent manner. Immunohistochemical staining showed that ATF3 expression was increased in the epidermis of psoriatic tissues. When ATF3 was overexpressed in keratinocytes using a recombinant adenovirus, poly(I:C)-induced inflammation was reduced. Conversely, ATF3 knockdown increased poly(I:C)-induced inflammation. Thus, ATF3 overexpression inhibited keratinocyte differentiation, while ATF3 knockdown promoted it.
Conclusion: ATF3 may be involved in the pathogenesis of psoriasis by influencing the inflammatory response and differentiation of keratinocytes. (Korean J Dermatol 2022;60(10):640∼646)

Background: Discoid lupus erythematosus (DLE) with alopecia of the scalp can result in permanent hair loss. Therefore, it is important to evaluate skin lesions and establish appropriate treatment plans for scalp DLE with alopecia.
Objective: We aimed to investigate the dermoscopic features of scalp DLE with alopecia and to determine the correlation between dermoscopic findings and treatment efficacy.
Methods: Thirty-one patients histopathologically diagnosed with scalp DLE and alopecia were included. We reviewed clinical photographs and dermoscopic findings of the patients and evaluated their treatment responses.
Results: The most frequent dermoscopic features of DLE with alopecia were follicular keratotic plugs (96.8%), white scales (71.0%), telangiectatic vessels (67.7%), and pigmentation (64.5%); followed by absent follicular openings (48.4%), white structureless areas (35.5%), follicular red dots (16.1%), and perifollicular whitish halo (12.9%). After at least 6 months of treatment, hair regrowth was observed in 22 patients (71.0%). Dermoscopic findings showed that white structureless areas, perifollicular whitish halo, absent follicular openings (especially when the alopecic patch involved >25% of the scalp), and moderate to severe telangiectatic vessels were associated with absence of hair regrowth.
Conclusion: Dermoscopy is a promising tool for evaluating lesions and predicting therapeutic outcomes in scalp DLE with alopecia. It may contribute to the establishment of appropriate treatment plan by determining whether hair loss is reversible. (Korean J Dermatol 2022;60(10):647∼656)

Background: Acral melanoma is the most common subtype of melanoma among Koreans, and regional or distant metastasis is an indicator of poor prognosis. Yes-associated protein (YAP), a key effector of the Hippo pathway, is known to induce tumor progression and metastasis in various cancers.
Objective: We aimed to analyze the clinical and histopathological characteristics of acral melanoma among Koreans and to evaluate their association with YAP expression.
Methods: This retrospective review included 27 patients with acral melanoma. Clinical features including age, sex, lesion site, and stage were obtained from the medical records and images. Biopsy slides of patients with acral melanoma were reviewed, and immunohistochemical staining for YAP was performed.
Results: The rate of YAP expression was significantly higher in patients having acral melanoma with regional or distant lymph node (LN) metastasis than in those without metastasis (n=4/5, 80.0% vs. n=2/22, 9.1%; p=0.004). Histopathologically, the rate of YAP expression was higher in patients having acral melanoma with lymphovascular invasion than in those without lymphovascular invasion (n=4/8, 50.0% vs. n=2/19, 10.5%; p=0.044). Among the 27 lesions, 14 (51.9%) were on stress-bearing sites such as the forefoot and heel. However, the rate of YAP expression did not differ significantly between weight-bearing and non-weight-bearing locations (p=0.834).
Conclusion: YAP expression is significantly associated with metastasis, especially LN metastasis, in patients with acral melanoma. Therefore, YAP expression may be used as a prognostic factor for LN metastasis and a target for novel treatments in patients with melanoma. (Korean J Dermatol 2022;60(10):657∼665)

Background: Prurigo nodularis (PN) is a chronic pruritic skin disorder with a large number of hyperkeratotic nodules. The precise mechanisms of its pathogenesis remain unknown. PN has been linked to atopic dermatitis (AD), but its association remains unclear.
Objective: We aimed to investigate the clinical, histological, and immunohistochemical characteristics of patients with PN and PN underlying AD (PN-AD).
Methods: Eight patients were recruited for PN, PN-AD, and eight normal subjects, respectively. Skin tissues were obtained from patients and healthy subjects for histological and immunohistochemical analyses.
Results: Histological examination showed increased epidermal thickness and dermal inflammatory cell counts in the PN-AD and PN groups compared to normal subjects. Immunohistochemical analyses revealed that the expression of interleukin (IL)-4, IL-13, IL-18, IL-31, IL-33, interferon (IFN)-γ, stromal-derived factor (SDF) 1-α and thymic stromal lymphopoietin (TSLP) was increased in the tissues of PN-AD and PN groups, in which the staining intensities of IL-4, IL-13, SDF1-α and TSLP in the PN-AD group were higher than those in the PN group, but the differences were not statistically significant. Conversely, the staining intensities of IL-18, IL-33 and IFN-γ were significantly higher in the PN group than those in the PN-AD group.
Conclusion: The pathogenesis of PN may differ from that of PN-AD, in which IL-18, IL-33 and IFN-γ may be associated, implying that epidermal injury is the initial cause of IL-18 and IL-33 induction, which then increases IFN-γ, resulting in the inflammatory process of PN. (Korean J Dermatol 2022;60(10):666∼674)

Onychogryphosis is a disorder of nail plate growth, which most commonly involves the toenails. It is characterized by opaque, yellow-brown thickening of the nail plate with associated marked convexity and elongation. Treatment for onychogryphosis can be conservative or operative depending on the cause and medical status of the patient. A 30-year-old male presented with onychogryphosis of the right and left toenails. Since the patient had shown recurrence after simple nail avulsion several years ago, the inverted T incision method and fusiform excision of the hypertrophic hyponychium were performed. No recurrence was observed during the 3-year follow-up period. Our results showed that nail avulsion combined with traction osteophyte removal is a suitable surgical method for treating onychogryphosis. (Korean J Dermatol 2022;60(10):675∼678)

Cyclosporine is one of the main therapeutic agents for psoriasis. It is known that psoriasis relapses 2∼3 months after discontinuation of cyclosporine, and exacerbation due to abrupt discontinuation of cyclosporine is uncommon. We report a case of psoriasis that was aggravated by cyclosporine cessation for guselkumab treatment, but improved with continuous administration of guselkumab. A 55-year-old man with a history of psoriasis presented with erythematous scaly plaques on the whole body. He had been treated with cyclosporine for 18 months and had received a subcutaneous injection of guselkumab 1 month previously. Two weeks after the first injection, the patient experienced exacerbation of the lesions. Considering the aggravation caused by abrupt discontinuation of cyclosporine, guselkumab administration was continued. The aggravated psoriatic lesions improved after additional guselkumab injections. At 16 weeks, the Psoriasis Area and Severity Index score was 0, which remained constant thereafter. (Korean J Dermatol 2022;60(10):679∼682)

Pityriasis rubra pilaris (PRP) is a rare chronic inflammatory papulosquamous disease of the skin. Its exact pathogenesis and incidence are not yet known. Clinically, it presents as palmoplantar keratoderma, hyperkeratotic follicular papules, and plaques. PRP can be diagnosed by histopathological examination, and the characteristic histopathological features include alternating orthokeratosis and parakeratosis, hypergranulosis, psoriasiform acanthosis with short and broad rete ridges, thick suprapapillary plates of the epidermis, and superficial perivascular inflammatory cell infiltrates. There are six subtypes of PRP based on clinical manifestations and age of onset. PRP is known to respond to acitretin, and treatment with other medications such as isotretinoin, methotrexate, and biologics results in symptomatic improvement. We present two cases of patients who developed type 2 and type 4 PRP following treatment with cyclosporine. (Korean J Dermatol 2022;60(10):683∼686)

Prurigo nodularis (PN) is a chronic inflammatory skin disease characterized by multiple nodules and papules, which are accompanied by intense pruritus. Treatment is challenging and requires a diverse approach. Recently, a few reports have described successful treatment of PN with dupilumab. We report a case of a patient with treatment-resistant PN who was successfully treated with dupilumab. Dupilumab was administered at the standard dose: an initial induction dose of 600 mg, followed by 300 mg every 14 days. Pruritus reduced after 2 weeks and almost completely disappeared after 4 weeks of treatment. (Korean J Dermatol 2022;60(10):687∼691)

Pleomorphic sarcoma is a mesenchymal neoplasm and divided into several groups based on histologic differentiation features, including stroma and infiltrated cells. Undifferentiated pleomorphic sarcoma is a rare type of pleomorphic sarcoma. It is called pleomorphic dermal sarcoma when the origin of tumor is the skin. The term of this tumor is confusing, and it has been changed continuously. In histopathologic study, it presents as well circumscribed tumor in which several pleomorphic and atypical cells are mixed. Herein, we report a rare pleomorphic dermal sarcoma showing characteristics of myxoinflammatory fibroblastic sarcoma. (Korean J Dermatol 2022;60(10):692∼696)