The initial molecular cytogenetic characteristics of blasts plays a significant role in determining the treatment course of B-cell acute lymphoblastic leukemia (B-ALL).B-ALL with intrachromosomal amplification of chromosome 21 (iAMP21) has been well known to have unfavorable prognosis. Also, there are previously recognized germline mutations that increase the risk of ALL, such as trisomy 21, Down syndrome. This case report is about a 16-year-old girl who presented with lymphadenitis, purpura, and fever followed by initial lab of elevated white blood cell with blasts.She had some notable facial features, but no typical Down syndrome related one.Bone marrow biopsy and fluorescence in situ hybridization finalized the diagnosis as B-ALL with iAMP21, high-risk group. The minimal residual disease-negative complete remission was achieved after the induction chemotherapy with Korean multicenter high-risk protocol. However, abnormal karyotype was sustained in bone marrow. Microarrays with her buccal swab raised the possibility that the abnormal karyotype was not from the leukemic blasts but rather from the germline. Although she underwent scheduled chemotherapy uneventfully as slow early responder type, thrombocytopenia and abnormal karyotype persisted, leading to the diagnosis of acute myeloid leukemia. Additional chemotherapy and peripheral blood stem cell transplantation was performed which resulted in engraftment. This case highlights the discovery of a constitutional genetic aberration, which played like a silent yet critical background factor for B-ALL with iAMP21. As the number of reported cases are limited, the role of germline chromosome 21 mutation as the indicator for prognosis of B-ALL should be studied further.

Although oxidative stress is the main pathophysiology of the development of diabetic neuropathy, oral administration of antioxidants has given disappointing results. Here, we hypothesized that local delivery of antioxidants would provide protective effects on Schwann cells due to the high concentration of local lesions. We prepared alpha-tocopherol (ATF)-loaded liposomes and tested their skin penetration after sonication. An in vitro study using IMS-32 cells was conducted to determine the level of reactive oxygen species (ROS) scavenging effects of ATF-liposomes. ATF reduced ROS in high-glucose-exposed IMS-32 cells in a dosedependent manner. ATF-liposomes also reduced the ROS level in vitro and ultrasound irradiation enhanced delivery to the dermis in porcine ear skin. This study showed that it is feasible to deliver ATF through the skin and can effectively reduce ROS. This model is worthy of development for clinical use.

OBJECTIVES: This study aimed to compare maternal outcomes and the home environment between non‑vulnerable families with children under 2 receiving universal home visiting services and vulnerable families receiving sustained home visiting services. METHODS: This study was conducted in Seoul, Korea, where the country’s first nurse‑led early childhood home visiting program was introduced. A total of 551 mother‑child dyads participated in cross‑sectional surveys conducted at various child ages (6±2 weeks, 6±1 months, 12±1 months, and 24±1 months). Universal home visiting services were provided within six weeks postpartum to non‑vulnerable families, while vulnerable families received sustained services consisting of 25 visits over 24 months. Maternal knowledge of sudden infant death syndrome (SIDS) and childcare, maternal distress, and the Korean Infant‑Toddler Home Observation for Measurement of Environment (K‑IT‑HOME) were assessed. RESULTS: Overall, the universal home visitation group demonstrated higher levels of maternal knowledge regarding SIDS and childcare compared to the sustained home visitation group (all p-values <0.05), while the sustained home visitation group reported higher levels of maternal distress (p<0.001). The total K‑IT‑HOME score was 1.47 points higher in the universal home visitation group than in the sustained home visitation group (p<0.001). No significant differences were observed in the acceptance, organization, or involvement subscales of the K‑IT‑HOME (all p-values >0.05). CONCLUSIONS This study demonstrated that disparities in maternal outcomes and home environments persisted in early childhood between the sustained and universal home visitation groups.

Basal cell adenocarcinoma, considered to be the malignant counterpart of basal cell adenoma, is a rare, low-grade malignant tumor of the salivary glands, accounting for 1-2% of salivary gland malignancies. It predominantly affects the parotid gland, while involvement of the minor salivary glands is exceptionally rare. This report presented a case of basal cell adenocarcinoma involving the left retromolar trigone in a 54-year-old woman. The initial provisional diagnosis suggested a benign or low-grade malignant salivary tumor. Advanced magnetic resonance imagingtechniques, including diffusion-weighted imaging and apparent diffusion coefficient analysis, aided in the preoperative prediction of malignancy, and an incisional biopsy confirmed the diagnosis of basal cell adenocarcinoma. This caseunderscored the challenge of distinguishing basal cell adenocarcinoma from benign salivary tumors, as clinical and imaging features often overlap. Surgical excision remains the primary treatment, yielding favorable outcomes;however, long-term follow-up is crucial due to the risk of recurrence.

Pertussis is endemic worldwide, with epidemics occurring every 2 to 5 years despite a high vaccination coverage.After limited circulation during the coronavirus disease 2019 (COVID-19) pandemic, pertussis cases have increased rapidly worldwide since mid-late 2023, returning to pre-pandemic patterns. In Korea, 90 cases of pertussis were reported from April 2020 to May 2023, with elderly individuals aged ≥65 years accounting for 48.9%. Pertussis cases have increased sharply since June 2024, showing a nationwide epidemic, with a large increase among adolescents aged 13–15 years. As of August 2024, the national incidence rate of pertussis was estimated to be 37.75 per 100,000 population, with the highest incidence of 526.2 per 100,000 population in 13-year-olds. In Europe, during 2023–2024, an increase in pertussis incidence among infants was observed, along with large increases in 10–19-yearolds. In China, the number of reported cases of pertussis has increased rapidly since late 2023, with an age shift to older children, increase of vaccine escape, and a marked increase in the prevalence of macrolide-resistant Bordetella pertussis. The recent global resurgence of pertussis is due to decreased opportunities for boosting immunity by natural infection during the COVID-19 pandemic in combination with waning of immunity-induced pertussis vaccines.

Background: Severe acute respiratory syndrome coronavirus 2, an RNA virus, exhibits variations in transmission power, severity rate, and vaccine effectiveness due to its mutable nature. We investigated the field epidemiological characteristics of the delta and omicron variants of coronavirus disease 2019 (COVID-19) clusters in a long-term care hospital. Materials and Methods: This study aimed to investigate the incidence, fatality, and vaccination effectiveness of confirmed COVID-19 cases caused by delta and omicron variants. The investigation focused on patients admitted to two long-term care hospitals in a Seoul autonomous district, comparing and analyzing relevant factors. Results: Among the COVID-19 cases, 101 (34.3%) exhibited delta variants, while 193 (65.4%) showcased omicron variants. The incidence rate of omicron variants, compared to delta variants, was 2.24 times higher (95% confidence interval [CI], 1.68–3.00). This elevation was particularly notable in women across all age groups, patients, workers, and individuals with a history of three or more vaccinations. Deaths were reported in 13 cases (52.0%) with the delta variant and 12 cases (48.0%) with the omicron variant. The fatality rate of the omicron variant, in comparison to the delta variant, was 0.09 times (95% CI, 0.44–2.26), indicating no significant difference. No discernible variations in variables were observed. Conclusion The noteworthy surge in outbreaks among female patients, workers engaged in outdoor activities, and the apparent ineffectiveness of vaccination against omicron mutations underscore the need for careful consideration in formulating quarantine measures.

Background: Carbapenem-resistant Acinetobacter baumannii (CRAB) represents a devastating and growing global threat, calling for new antibiotic treatments. In Korea, the challenge of treating CRAB is compounded by high nosocomial acquisition rates and limited availability of novel antibiotics. Minocycline, a semisynthetic tetracycline derivative, has been proposed as a therapeutic option for CRAB infections. Nonsusceptibility to minocycline may occur through the efflux pump, TetB. The prevalence of tetB in A. baumannii has increased, along with higher minocycline minimum inhibitory concentrations (MICs). We aimed to evaluate minocycline susceptibility rates in clinical strains of CRAB, and the association between tetB carriage and minocycline susceptibility across different genotypes. Materials and Methods: Representative CRAB blood isolates were collected from Asan Medical Center, Seoul.Minocycline susceptibility was assessed using the Clinical and Laboratory Standards Institute (CLSI) breakpoint (≤4 mg/L) and the proposed pharmacokinetics (PK)/pharmacodynamics (PD) breakpoint (≤1 mg/L). Tigecycline was used as a comparator, and its susceptibility breakpoint for Enterobacterales defined by EUCAST was applied (≤0.5 mg/L).The presence of tetB was detected by PCR, and multilocus sequence typing (MLST) was performed using seven housekeeping genes. Results: Of the 160 CRAB blood isolates, 83.8% were susceptible to minocycline by the CLSI criteria, and 50.6% were PK-PD susceptible by the PK-PD criteria. The minocycline minimum inhibitory concentration (MIC)50 /MIC90 was 1/8 mg/L. tetB was present in 49% of isolates and was associated with a higher minocycline MIC (MIC50/90 2/8 mg/L vs. 1/2 mg/L). No clear correlation was observed between tetB positivity and tigecycline MIC. Nine MLSTs were identified, with significant differences in tetB carriage rates between the major sequence types. Notably, ST191, associated with non-tetB carriage and greater susceptibility to minocycline, declined over the study period (P=0.004), while ST451, associated with tetB carriage, increased. Conclusion tetB was present in 49% of CRAB isolates and was associated with higher MICs and non-susceptibility by both CLSI and PK-PD criteria. However, absence of tetB was not a reliable predictor of minocycline PK-PD susceptibility. Additionally, shifts over time towards genotypes with reduced minocycline susceptibility were observed. Further research is needed to correlate these findings with clinical outcomes and identify additional resistance mechanisms.

Background and Objectives: This study was performed to comprehensively examine the amplitudes of the binaural interaction components (BICs) elicited by chirps, clicks, and 500 Hz tone-burst stimuli in individuals with normal hearing. Electrophysiological evidence of BICs was obtained and assessed for correlations with interaural time difference (ITD) and interaural level difference (ILD). Subjects and Methods: Sixteen adults (4 males and 12 females) with normal hearing participated in this study. Auditory brainstem responses (ABRs) to chirp, click, and 500 Hz tone-burst stimuli were recorded, and BICs were derived based on wave V. The behavioral thresholds of ITDs and ILDs across multiple frequencies were obtained and analyzed. Results: BICs were found in most participants, regardless of stimulus type. The amplitudes of BICs elicited by chirps were the highest, followed by those elicited by clicks and 500 Hz tone-bursts. A significant correlation was found between the amplitudes of chirp-evoked BICs and the thresholds of 500 Hz ITDs and ILDs. Conclusions This study found that chirp stimuli may be effective in eliciting BIC and predicting behavioral binaural interaction processing at low frequencies.

Purpose: To evaluate the differences in the level of concerns regarding exotropia surgery according to the perspectives regarding surgery and basic characteristics of parents of pediatric patients with intermittent exotropia in South Korea. Methods: This study included the parents of pediatric patients with intermittent exotropia who underwent surgery at five hospitals, between June 2022 and February 2023. Parental perspectives, basic characteristics, and levels of concern regarding surgery were assessed using a questionnaire. We investigated the differences in concern levels according to perspectives regarding surgery and basic characteristics among parents, such as sex, age, residential area, and the most influential factors in the decision-making for surgery. Results: A total of 266 parents were included (228 mothers; age, 40.0±4.7 years). Parents who chose surgery for subjective symptoms had higher levels of concern about hemorrhage, conjunctival redness, and persistent overcorrection than did those who chose surgery for cosmetic reasons (all p < 0.05). Fathers were more concerned about postoperative pain, compared to mothers (p = 0.039). Parents in their 40s and 50s had higher levels of concern about the hospital environment compared with those in their 20s and 30s (p = 0.003). Concern did not significantly differ by residential area. Conclusions The level of concern regarding surgery differed according to the perspectives and characteristics of the parents of pediatric patients with intermittent exotropia. Parents who chose surgery for subjective symptoms of exotropia had a higher level of concern than did those who chose surgery for cosmetic reasons. The concern level differed according to the parents’ sex and age but not their residential area.

Background and Objectives: Various distinct types of tumors can develop in the auricles; however, those have not been thoroughly studied clinically. The aim of the study is to assess the clinical nature of auricular tumors.Subjects and Method We retrospectively reviewed medical records and pathological findings in patients with auricular tumors who underwent surgical interventions at a single institution from January 2011 to October 2023. Cases in which the location of the tumor could be identified and pathological results were confirmed were included. We analyzed age, sex, tumor location and size, tumor occurrence period and causes, recurrence, and pathological results. Results: A total of 98 auricular tumors were included in the study. Auricular tumors were most commonly found on the lobule (32.3%), followed by the helix (30.1%) and the posterior auricle (15.1%). The most prevalent pathological type of auricular tumors was an epidermal cyst (45.2%), followed by keloid (21.5%). A single case of squamous cell carcinoma was reported. Eight tumors recurred following surgical resection, with five cases of keloid, two cases of epidermal cyst, and one case of squamous cell carcinoma, with an average recurrence interval of 6.1 months. Conclusion The present study assessed the largest number of auricular tumors collected in a single institution. Tumors with diverse clinical characteristics can develop in the auricle, and cosmetic considerations must be taken into account before undergoing surgical treatment. The findings of the present study could provide proper approaches to the auricular tumors.