Background: Direct immunofluorescence (DIF) is a histochemical technique used to detect tissue-bound autoantibodies and diagnose various immune-mediated skin diseases. Objective: This study aimed to evaluate the sensitivity of DIF for each disorder, and the consistency between clinical, histopathological, and DIF results. Methods: A retrospective study was conducted in 194 patients who underwent skin biopsy and DIF testing at our hospital between January 2011 and December 2021. An antibody panel against immunoglobulin G (IgG), IgA, IgM, C3, C1q, and fibrinogen was used. The concordance rate and κ-coefficient between the clinical, histopathological, and DIF results were evaluated. Results: DIF was observed to be positive in 87 cases; 51 cases of immune-mediated bullous diseases, seven cases of connective tissue diseases (CTDs), 25 cases of vasculitis, and four cases of other diseases. The overall sensitivity of DIF for immune-mediated bullous diseases was 71.8%, which was higher than that of histopathology (64.8%). In CTDs and vasculitis, the overall sensitivities of DIF were 30.4% and 65.8%, respectively, which were lower than those of histopathology (73.9% and 84.2%, respectively). In addition, good concordance among the clinical, histological, and DIF results was observed. Conclusion DIF is a useful diagnostic method, especially for immune-mediated bullous diseases, lupus erythematosus, and Henoch-Schonlein purpura. However, in other CTDs and vasculitis cases, the sensitivity of DIF is relatively low. Therefore, the diagnostic value of DIF along with clinical and histopathological findings will be maximized only when the DIF test is performed for appropriate diseases.

Eosinophilic dermatosis of hematological malignancy (EDHM) is a rare condition associated with various hematologic malignancies, characterized by pruritic skin eruptions. We present a case of a 66-year-old woman with follicular lymphoma who developed urticarial and vesicular lesions indicative of EDHM following chemotherapy.The diagnosis was confirmed through histological analysis, revealing eosinophilic infiltration. Treatment included additional chemotherapy sessions and topical corticosteroids, resulting in complete resolution of skin lesions and lymphoma. EDHM requires careful differentiation based on clinical and histological findings. The pathogenesis remains unclear, but addressing underlying hematologic malignancies appears crucial in management. Early recognition of EDHM is essential for appropriate intervention due to its limited therapeutic options.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive lymphoma with an overall incidence of 0.04 cases per 100,000 people. BPDCN is a hematopoietic clonal neoplasm that originates from plasmacytoid dendritic cell precursors. A 63-year-old man presented with multiple erythematous nodules over his whole body, including his face, trunk, and both upper and lower extremities that appeared 1 month ago. Skin biopsy showed diffuse dermal infiltration by monomorphic atypical lymphocytes with large, irregular nuclei and scant cytoplasms. Immunohistochemical staining was positive for CD4, CD56, and CD123. The karyotype test showed abnormalities in male chromosomes 47, XY, ＋8 [2]/46, and XY [25], and mutations in DNMT3A, TET2, SRSF2, and ATRX genes were identified in a next-generation sequencing (NGS)-based acute myeloid leukemia gene panel test. The patient was diagnosed with BPDCN and treated with a KALLA 1406 regimen; however, he died on the 17th day of treatment.

Dystrophic epidermolysis bullosa (DEB) pruriginosa is a rare subtype of DEB characterized by multiple, violaceous, and severe pruritic lichenified nodules along with blisters. Here, we report the case of a Korean male who, since the age of 3 years, had multiple pruritic nodules with blisters on both lower extremities. Genetic testing is required to diagnose DEB pruriginosa because its clinical and histologic features are inconclusive. We identified compound heterozygous COL7A1 variants of c.5797C>T (p.R1933*) and c.3301C>T (p.R1101W) in the patient, leading to a diagnosis of recessive DEB pruriginosa. Among the variants identified, c.3301C>T is a novel missense variant that has not been reported previously. This variant is in exon 26, which encodes von Willebrand factor A (vWFA) in collagen type VII. vWFA is known to preserve normal dermal structures by interacting with dermal collagens and basement membranes. Considering that this variant contradicts the general concept that autosomal dominant inheritance is more common and that variants typically occur in the triple helical collagenous domain of COL7A1 in DEB pruriginosa, we focus on the rarity of this case and the possible pathogenic role of the c.3301C>T (p.R1101W) variant.

Purpose: This study investigated the mediating effect of patient participation culture in the relationship between ethical leadership and performance in patient-engaged nursing services. Methods: This study employed a cross-sectional descriptive online survey design. The sample comprised 104 nurses from small- and middle-sized Korean hospitals.Data were collected between May 10 and September 10, 2019 using the Smart Patient Engagement Assessment Checklist, Korean versions of the Patient Participation Culture Tool for healthcare workers, the Ethical Leadership Scale, and a questionnaire about nurses' demographic and work characteristics. A mediation analysis was conducted using multiple regression and a simple model applying the PROCESS macro using SPSS/WINdows software version 26.0. Results: Ethical leadership directly affected (c'=0.28, p<.001) performance in patient-engaged nursing services. Patient participation culture partially mediated the relationship between ethical leadership and performance in patient-engaged nursing services (a ․ b=0.51×0.20=0.10, 95% Boot CI=0.18~0.20). Conclusion Optimizing the patient participation culture and adherence to ethical leadership among hospital administrators and managers can improve nurses' performance in patient-engaged nursing services. Nurse managers' ethical leadership should be strengthened, and patient participation culture should be encouraged at policy levels through systematic nurse education on patient safety and engagement to enhance performance-engaged nursing services.

Myxoinflammatory fibroblastic sarcoma (MIFS) is a rare neoplasm that is frequently located in the distal extremities. Emerging evidence suggests that MIFS can also affect the proximal limbs, trunk, and scalp, and aggressive clinical courses have been noted. We report a case of MIFS that occurred suddenly in the patient’s forearm and grew rapidly within 2 weeks. A level of Ki-67 was observed in the patient’s lesion, which constitutes a considerable finding compared with most MIFS cases. The patient underwent surgical tumor removal, and no evidence of recurrence was noted. We highlight this case in view of its sudden occurrence and rapid local progression, which contradicts the usual features of this disease, suggesting that this clinical course might be attributable to the high Ki-67 value.

The latissimus dorsi flap has high vascularity and is helpful for the reconstruction of infected areas. Herein, we present a patient with recurrent infections and soft-tissue defects who underwent cranial reconstruction using a free latissimus dorsi flap. The patient had undergone craniectomy and reconstruction using alloplastic bone 18 years previously. A scalp defect accompanied by infection occurred five years ago, and patient underwent reconstruction using a free flap at another hospital; however, the problem persisted. After debridement and bone flap removal, the right latissimus dorsi musculocutaneous flap was elevated, and the thoracodorsal artery and vein were anastomosed end-to-end to the right superficial temporal artery and vein. Methicillin-resistant Staphylococcus aureus was eradicated, and the flap survived. Cranioplasty was performed eight months later, and one year follow-up proceeded without complications. Effective reconstruction and cranioplasty are possible using the free latissimus dorsi musculocutaneous flap, even on scalp with persistent infections and soft-tissue defects.

Purpose: Epidermal growth factor receptor kinase domain duplication (EGFR-KDD) is a rare and poorly understood oncogenic mutation in non–small cell lung cancer (NSCLC). We aimed to investigate the acquired resistance mechanism of EGFR-KDD against EGFR-TKIs. Materials and Methods: We identified EGFR-KDD in tumor tissue obtained from a patient with stage IV lung adenocarcinoma and established the patient-derived cell line SNU-4784. We also established several EGFR-KDD Ba/F3 cell lines: EGFR-KDD wild type (EGFR-KDDWT), EGFR-KDD domain 1 T790M (EGFR-KDDD1T), EGFR-KDD domain 2 T790M (EGFR-KDDD2T), and EGFR-KDD both domain T790M (EGFR-KDDBDT). We treated the cells with EGFR tyrosine kinase inhibitors (TKIs) and performed cell viability assays, immunoblot assays, and ENU (N-ethyl-N-nitrosourea) mutagenesis screening. Results: In cell viability assays, SNU-4784 cells and EGFR-KDDWT Ba/F3 cells were sensitive to 2nd generation and 3rd generation EGFR TKIs. In contrast, the T790M-positive EGFR-KDD Ba/F3 cell lines (EGFR-KDDT790M) were only sensitive to 3rd generation EGFR TKIs. In ENU mutagenesis screening, we identified the C797S mutation in kinase domain 2 of EGFR-KDDBDT Ba/F3 cells. Based on this finding, we established an EGFR-KDD domain 1 T790M/domain 2 cis-T790M+C797S (EGFR-KDDT/T+C) Ba/F3 model, which was resistant to EGFR TKIs and anti-EGFR monoclonal antibody combined with EGFR TKIs. Conclusion Our study reveals that the T790M mutation in EGFR-KDD confers resistance to 1st and 2nd generation EGFR TKIs, but is sensitive to 3rd generation EGFR TKIs. In addition, we identified that the C797S mutation in kinase domain 2 of EGFR-KDDT790M mediates a resistance mechanism against 3rd generation EGFR TKIs.

Purpose: This study aimed to evaluate the validity and reliability of the Korean version of the Readiness for Practice Survey (K-RPS). Method: The English Readiness for Practice Survey was translated into Korean using the Translation, Review, Adjudication, Pretesting, and Documentation (TRAPD) method. Secondary data analysis was performed using the dataset from the New Nurse e-Cohort study (Panel 2020) in South Korea. This study used a nationally representative sample of 812 senior nursing students. Exploratory and confirmatory factor analyses were also conducted. Convergent validity within the items and discriminant validity between factors were assessed to evaluate con-struct validity. Construct validity for hypothesis testing was evaluated using convergent and discriminant validity. Ordinary α was used to assess reliability. Results: The K-RPS comprises 20 items examining four factors: clinical problem solving, learning experience, professional responsibilities, and professional preparation. Although the convergent validity of the items was successfully verified, discriminant validity between the factors was not. The K-RPS construct validity was verified using a bi-factor model (CMIN/DF 2.20, RMSEA .06, TLI .97, CFI .97, and PGFI .59). The K-RPS was significantly correlated with self-esteem (r = .43, p < .001) and anxiety about clinical practicum (r = - .50, p < .001). Internal consistency was reliable based on an ordinary α of .88. Conclusion The K-RPS is both valid and reliable and can be used as a standardized Korean version of the Readiness for Practice measurement tool.