Current ABO titration methods lack standardization and harmonization. We analyzed the consistency of ABO antibody titer testing among Korean laboratories and discussed future directions for standardization by analyzing external quality control data collected by the Korean Association of External Quality Assessment Service over 5 yrs (2019–2023). The analysis included the number of participating institutions and methods, as well as the proportion of acceptable results. To compare column agglutination technology (CAT) and tube methods, we created a normalized variable: ([log 2 titer of laboratory test result]–[mean of log 2 titer for the peer group]). The number of participating institutions and methods increased over time. The use of CAT methods expanded, whereas that of tube methods declined. The proportion of acceptable results ranged from 84.0% to 100%, with no significant differences between CAT and tube methods. An F-test revealed no significant variance differences among institutions using these methods. Tube methods demonstrated lower variance in anti-human globulin testing, and room temperature tube methods exhibited lower variance than that of CAT methods. Domestic laboratories demonstrated highquality performance in ABO antibody titer testing, with no significant differences in acceptable result rates or variance across methods. Continuous efforts toward standardization remain essential.

Background: While polystyrene microplastics (PS-MPs) are emerging as potentially significant health threats, linked to cancer and reproductive dysfunction, their precise effects on human health remain largely unknown. We aimed to investigate the underlying mechanisms promoting microplastic-induced damage in the reproductive system. Methods: Thirty C57BL/6 male mice were randomly allocated into six equal-sized groups.Mice were exposed to fluorescent PS-MPs (5 µm, < 18%, green) at a dose of 1 and 3 mg/dL via oral gavage for 28 and 56 days, respectively (control, 0 mg/dL). The presence of antibodies and inflammatory and oxidative stress markers were evaluated using western blotting. Sperm analysis was also performed. Mouse testis Sertoli TM4 cells were divided into two groups:control (medium only) and PS-MPs (medium containing, 1,000 μg/mL) groups and cultured in vitro for 1, 24, 48, or 72 hours. The cells were cultured in a Ham’s F12: Dulbecco's Modified Eagle Medium medium with 0.25% fetal bovine serum at 37°C with humidified atmosphere of 5% carbon dioxide in the air. Protein analyses for interleukin (IL)-6, IL-10, NADPH-oxidase (NOX)-2, NOX-4, hypoxia-inducible transcription factor (HIF)-2α, monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor (TNF)-α, and transforming growth factor (TGF)-β were performed using western blotting. Results: The testes were evaluated after 28 and 56 days of exposure. Varying sizes of PS-MPs were detected in the testes (ranging from 5.870 to 7.768 µm). Significant differences in sperm concentration, motility, and the proportion of normal sperm were observed between the two groups. An increase in TGF-β, HIF-2α, and NOX-4 levels was observed using western blot analysis. However, no dose-dependent correlations were observed between the two groups.In vitro evaluation of the PS-MPs group displayed PS-MP penetration of the lumen of Sertoli cells after 1 hour. Further PS-MP aggregation within Sertoli cells was observed at 24, 48, and 72 hours. A significant increase in inflammatory protein expressions (IL-10, TGF-β, MCP-1, IL-6, TNF-α, and HIF-2α) was observed through western blotting, although oxidative agents did not show a significant increase. Conclusion PS-MPs induced reproductive dysfunction in male mice provide new insights into PS-MPs-associated toxicity in mammals.

The Korean Triage and Acuity Scale (KTAS) Committee under the Korean Society of Emergency Medicine developed a Korean pre-hospital emergency patient classification tool (Pre-hospital Korean Triage and Acuity Scale [Pre-KTAS]) under contract from the Ministry of Health and Welfare, Korea. The classification tool was developed separately for adults and children. The patient’ s emergency level is classified into five distinct levels and is the same as the KTAS classification system, which is a hospital-level emergency patient classification tool.

Background: Daily usage of facial masks during coronavirus disease 2019 pandemic influenced on facial dermatoses. Objective: This study investigated the impact of mask-wearing habits on facial dermatoses. Methods: A nationwide, observational, questionnaire-based survey was conducted from July through August 2021, involving 20 hospitals in Korea. Results: Among 1,958 facial dermatoses, 75.9% of patients experienced aggravation or development of new-onset facial dermatoses after wearing masks. In aggravated or newly developed acne patients (543 out of 743), associated factors were healthcare provider, female gender, and a long duration of mask-wearing. Irritating symptoms, xerosis, and hyperpigmentation were more frequently observed in this group. Aggravated or newly developed rosacea patients (515 out of 660) were likely to be female, young, and have a long duration of mask-wearing per day. Seborrheic dermatitis patients who experienced aggravation or de novo development (132 out of 184) were younger, and they more frequently involved the chin and jaw in addition to the nasolabial folds and both cheeks. Contact dermatitis patients (132 out of 147) with aggravation or de novo development tended to be female, involve both cheeks, and complain of pruritus. Aggravated or newly developed atopic dermatitis patients (165 out of 224) were more likely to be female, and had a higher baseline investigator global assessment score before mask-wearing. Conclusion Clinical features and factors related to aggravation were different according to the types of facial dermatoses.

Background: More than half of acne patients have truncal acne on their chest, back, and shoulders. However, since most studies on acne have focused on the face, data on clinical characteristics and proper management for truncal acne are insufficient. Objective: To establish a Korean Acne Rosacea Society (KARS) consensus for experts’ perception and treatment patterns of truncal acne. Methods: We conducted two rounds of the Dephi technique to gather expert opinion and reach a consensus on truncal acne. The first round comprised 48 questionnaires focusing on various aspects such as epidemiology, clinical features, diagnosis, treatment, prognosis and more, while second rounds consisted of 26 questionnaires. Results: A total of 36 dermatologists (36/38 KARS members, 94.7%) completed this survey. In the first-round survey, consensus was reached on 20 out of the 48 questions (41.7%). In the secondround questionnaire, consensus was achieved on 9 of the 26 questions (34.6%). The most unresponsive lesion to truncal acne treatment was scars (atrophic/hypertrophic). The most commonly used treatments for each non-inflammatory and inflammatory truncal acne lesions were selected to use topical retinoids (78.1% of the responders) and oral antibiotics (93.8% of the responders). Conclusion Our study has yielded valuable insights into the epidemiology, clinical manifestations, diagnosis, treatment, and quality of life of patients with truncal acne. We anticipate that this study will inspire further comprehensive research for individuals with truncal acne.

Transfusion is an essential life-sustaining treatment for many patients. However, unnecessary transfusion has been reported to be related to worse patient outcomes. Further, owing to the recent pandemic, blood supply has been more challenging to maintain. Many studies have been conducted to elucidate the optimal transfusion threshold for many clinical conditions, and most suggested that a restrictive transfusion strategy has advantages over a liberal transfusion strategy. Hematologic disorders, which require chronic transfusion in many cases, have not been the main subjects of such studies, and only little evidence is available regarding the optimal transfusion threshold in these patients.According to several recent studies, a liberal transfusion strategy is preferable for patients with hematologic disorders due to their quality of life. A patient-centered approach is needed for proper management of hematologic disorders.

Background: This study aimed to evaluate whether the effect of tachycardia varies according to the degree of tissue perfusion in septic shock. Methods: Patients with septic shock admitted to the intensive care units were categorized into the tachycardia (heart rate > 100 beats/min) and non-tachycardia (≤ 100 beats/min) groups. The association of tachycardia with hospital mortality was evaluated in each subgroup with low and high lactate levels, which were identified through a subpopulation treatment effect pattern plot analysis. Results: In overall patients, hospital mortality did not differ between the two groups (44.6% vs. 41.8%, P = 0.441), however, tachycardia was associated with reduced hospital mortality rates in patients with a lactate level ≥ 5.3 mmol/L (48.7% vs. 60.3%, P = 0.030; adjusted odds ratio [OR], 0.59, 95% confidence interval [CI], 0.35–0.99, P = 0.045), not in patients with a lactate level < 5.3 mmol/L (36.5% vs. 29.7%, P = 0.156; adjusted OR, 1.39, 95% CI, 0.82–2.35, P = 0.227). Conclusion In septic shock patients, the effect of tachycardia on hospital mortality differed by serum lactate level. Tachycardia was associated with better survival in patients with significantly elevated lactate levels.

Background: Data illustrating the impact of atopic dermatitis (AD) on lives of adults with AD in South Korea are limited. Objective: To assess the AD disease severity and its impact on quality of life (QoL) in patients with AD from South Korea. Methods: Patients with AD utilizing the specialist dermatology services of major hospitals in South Korea were assessed for disease severity using Eczema Area and Severity Index (EASI) score, for QoL using Dermatology Life Quality Index (DLQI) (for QoL), and for comorbidities and treatment experience via retrospective review of 12-month medical records. Clinical and sociodemographic characteristics were also measured. Results: Of the 1,163 patients, 695 (59.8%) were men (mean age [years]±standard deviation: 31.6±12.1). Overall, 52.9% (n=615) patients had moderate-to-severe disease (EASI>7).The QoL of 72.3% (n=840) patients was affected moderately-to-severely (DLQI score: 6~30).Systemic immunosuppressants were used ≥1 over past 12 months in 51.9% (n=603) patients, and the most commonly used were cyclosporines (45.7%, n=531) and systemic corticosteroids (40.5%, n=471). Approximately, 10.8% (n=126) patients consulted or received treatment for AD-related eye problem. Of these, 40% (n=50) patients reported poor, very poor, or completely blind status; approximately, 16.7% patients (n=192) reported having depression or anxiety; and 35.5% (n=410) reported suicidal ideation or suicidal attempt. Conclusion A large proportion of patients had moderate-to-severe AD, a compromised QoL, and ocular or mental health comorbidities, indicating a high disease burden despite systemic treatment. These findings highlight the importance of a holistic approach for the evaluation and treatment of patients with AD.

Background: Fungal melanonychia (FM) is a rare nail disorder that presents as dark pigmentation in the nail plate because of fungal nail infection. The diagnosis of FM is occasionally confusing because its appearance is similar to melanonychia due to other causes including malignant melanoma. Dermoscopy could help increase the accuracy of diagnosing the cause of pigmented nail lesions. However, dermoscopic features of FM are not well elucidated. Objective: This study aimed to investigate clinical and dermoscopic characteristics of FM. Methods: The clinical features and dermoscopic findings of 20 patients diagnosed with FM and 14 patients diagnosed with subungual melanoma the Department of Dermatology of Pusan National University Hospitals (Busan and Yangsan) were retrospectively reviewed. Results: FM mainly occurred as a solitary form in the toenail. Patients in the FM group were older than those in the subungual melanoma group. The most distinguishable general dermoscopic features in FM were a distal diffuse pattern, distal linear pattern, and light brown to yellowish color. FM-associated specific dermoscopic patterns such as the reverse triangular pattern, subungual hyperkeratosis, scale on the nail surface, and white or yellowish streaks were dominantly observed in the FM group compared to the subungual melanoma group. Conclusion FM-associated dermoscopic patterns and distal diffuse and linear patterns could be helpful diagnostic clues for differential diagnosis of FM from subungual melanoma.