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.

Purpose: We investigated the consistent efficacy and safety of eflapegrastim, a novel long-acting granulocyte-colony stimulating factor (G-CSF), in Koreans and Asians compared with the pooled population of two global phase 3 trials. Materials and Methods: Two phase 3 trials (ADVANCE and RECOVER) evaluated the efficacy and safety of fixed-dose eflapegrastim (13.2 mg/0.6 mL [3.6 mg G-CSF equivalent]) compared to pegfilgrastim (6 mg based on G-CSF) in breast cancer patients who received neoadjuvant or adjuvant docetaxel/cyclophosphamide. The primary objective was to demonstrate non-inferiority of eflapegrastim compared to pegfilgrastim in mean duration of severe neutropenia (DSN) in cycle 1, in Korean and Asian subpopulations. Results: Among a total of 643 patients randomized to eflapegrastim (n=314) or pegfilgrastim (n=329), 54 Asians (29 to eflapegrastim and 25 to pegfilgrastim) including 28 Koreans (14 to both eflapegrastim and pegfilgrastim) were enrolled. The primary endpoint, DSN in cycle 1 in the eflapegrastim arm was non-inferior to the pegfilgrastim arm in Koreans and Asians. The DSN difference between the eflapegrastim and pegfilgrastim arms was consistent across populations: –0.120 days (95% confidence interval [CI], –0.227 to –0.016), –0.288 (95% CI, –0.714 to 0.143), and –0.267 (95% CI, –0.697 to 0.110) for pooled population, Koreans and Asians, respectively. There were few treatment-related adverse events that caused discontinuation of eflapegrastim (1.9%) or pegfilgrastim (1.5%) in total and no notable trends or differences across patient populations. Conclusion This study may suggest that eflapegrastim showed non-inferior efficacy and similar safety compared to pegfilgrastim in Koreans and Asians, consistently with those of pooled population.

BACKGROUND: Adipose-derived stem cells (ADSCs) exert immunomodulatory effects in the treatment of transplant rejection. This study aimed to evaluate the effects of ADSCs on the skin graft survival in a human-to-rat xenograft transplantation model and to compare single and multiple injections of ADSCs. METHODS: Full-thickness human skin xenografts were transplanted into the backs of Sprague–Dawley rats. The rats were injected subcutaneously on postoperative days 0, 3, and 5. The injections were as follows: triple injections of phosphate-buffered saline (PBS group), a single injection of ADSCs and double injections of PBS (ADSC 9 1 group), and triple injections of ADSCs (ADSC 9 3 group). The immunomodulatory effects of ADSCs on human skin xenografts were assessed. RESULTS: Triple injections of ADSCs considerably delayed cell-mediated xenograft rejection compared with the PBS and ADSC 9 1 groups. The vascularization and collagen type 1–3 ratios in the ADSC 9 3 group were significantly higher than those in the other groups. In addition, intragraft infiltration of CD3-, CD4-, CD8-, and CD68-positive cells was reduced in the ADSC 9 3 group. Furthermore, in the ADSC 9 3 group, the expression levels of proinflammatory cytokine interferon-gamma (IFN-c) were decreased and immunosuppressive prostaglandin E synthase (PGES) was increased in the xenograft and lymph node samples. CONCLUSION This study presented that triple injections of ADSCs appeared to be superior to a single injection in suppressing cell-mediated xenograft rejection. The immunomodulatory effects of ADSCs are associated with the downregulation of IFN-c and upregulation of PGES in skin xenografts and lymph nodes.

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.

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.

Background: Total cholesterol concentration measurement is important in the diagnosis of dyslipidemia and evaluation of cardiovascular disease risk factors. Measurement reliability for obtaining an accurate total cholesterol concentration requires procedure standardization. We evaluated the standardization status for total cholesterol concentration measurement through Korean external quality assessment (EQA) data analysis. Methods: This study involved 1,670 laboratories that participated in the EQA of total cholesterol concentration measurements in 2019 for 32 products from different manufacturers. The target concentrations of three quality control (QC) materials (samples A, B, and C) were measured using the reference method and compared with EQA data. The performance criteria for total cholesterol concentration measurement were based on the National Cholesterol Education Program guidelines, with ± 3% inaccuracy. Results: The target values and inaccuracies of the QC material based on the reference method measurements were 254.65 ± 7.64, 108.30 ± 3.25, and 256.29 ± 7.69 mg/dL (6.59 ± 0.20, 2.80 ± 0.08, and 6.63 ± 0.20 mmol/L) for samples A, B, and C, respectively.The performance criteria were not met in 42.7% laboratories for sample A, 68.4% of laboratories for sample B, and 38.0% laboratories for sample C. Conclusions Despite significant efforts to accurately measure total cholesterol concentrations, further actions are needed for measurement standardization. Manufacturers reporting values that differ from target values should check calibrator traceability; additional efforts to accurately measure total cholesterol concentrations are required for laboratories that use products from these manufacturers.