This study aimed to evaluate the differences in the baseline characteristics and patterns of antibiotic usage among hospitals based on their participation in the Korea National Antimicrobial Use Analysis System (KONAS). We obtained claims data from the National Health Insurance for inpatients admitted to all secondary- and tertiary-care hospitals between January 2020 and December 2021 in Korea. 15.9% (58/395) of hospitals were KONAS participants, among which the proportion of hospitals with > 900 beds (31.0% vs.2.6%, P < 0.001) and tertiary care (50.0% vs. 5.2%, P < 0.001) was higher than that among non-participants. The consumption of antibiotics targeting antimicrobial-resistant gram positive bacteria (33.7 vs. 27.1 days of therapy [DOT]/1,000 patient-days, P = 0.019) and antibiotics predominantly used for resistant gram-negative bacteria (4.8 vs. 3.7 DOT/1,000 patient-days, P = 0.034) was higher in KONAS-participating versus -non-participating hospitals. The current KONAS data do not fully represent all secondary- and tertiary-care hospitals in Korea; thus, the KONAS results should be interpreted with caution.

Background: Non-palpable splenomegaly in patients with polycythemia vera (PV) has seldom been addressed. In this retrospective study, we evaluated non-palpable, volumetric splenomegaly defined based on age- and body surface area (BSA)–matched criteria in patients with PV diagnosed according to the 2016 World Health Organization diagnostic criteria. Methods: Patients with PV who underwent abdominal computed tomography (CT) and who had palpable splenomegaly at diagnosis from January 1991 to December 2020 at Chungnam National University Hospital were enrolled. The spleen volume of each patient was determined by volumetric analysis of abdominal CT and adjusted for the patient’s age and BSA. Then the degree of splenomegaly was classified as no splenomegaly, borderline volumetric splenomegaly, overt volumetric splenomegaly, or palpable splenomegaly. Results: Of the 87 PV patients enrolled, 15 (17.2%) had no splenomegaly, whereas 17 (19.5%), 45 (51.7%), and 10 (11.5%) had borderline volumetric, overt volumetric, and palpable splenomegaly, respectively. The degree of splenomegaly did not affect the cumulative incidence of thrombotic vascular events (10-year incidence: 7.7%, 0%, 22.3%, and 50.7%, respectively, P = 0.414). By contrast, splenomegaly tended to adversely affect myelofibrotic transformation (10-year cumulative incidence: 0%, 0%, 7.1%, and 30.3%, respectively, P = 0.062). Moreover, the cumulative incidence of myelofibrotic transformation was significantly higher in patients with overt volumetric or palpable splenomegaly than those with no or borderline volumetric splenomegaly (10-year incidence: 0% vs. 10.3%, respectively; 15-year incidence: 0% vs. 26.3%, respectively, P = 0.020). Overall survival (OS) differed among patients with different degrees of splenomegaly (15-year OS: 100%, 78.6%, 71.7%, and 51.9%, respectively, P = 0.021). Conclusion The degree of splenomegaly, including volumetric splenomegaly, based on ageand BSA-matched reference spleen volumes at diagnosis reflects disease progression in PV patients. Therefore, volumetric splenomegaly should be evaluated at the time of diagnosis and taken into consideration when predicting the prognosis of patients with PV.

Background/Aims: The prospective Crohn’s Disease Clinical Network and Cohort Study is a nationwide multicenter cohort study of patients with Crohn’s disease (CD) in Korea, aiming to prospectively investigate the clinical features and long-term prognosis associated with CD. Methods: Patients diagnosed with CD between January 2009 and September 2019 were prospectively enrolled. They were divided into two cohorts according to the year of diagnosis: cohort 1 (diagnosed between 2009 and 2011) versus cohort 2 (between 2012 and 2019). Results: A total of 1,175 patients were included, and the median follow-up duration was 68 months (interquartile range, 39.0 to 91.0 months). The treatment-free durations for thiopurines (p<0.001) and anti-tumor necrosis factor agents (p=0.018) of cohort 2 were shorter than those of cohort 1. Among 887 patients with B1 behavior at diagnosis, 149 patients (16.8%) progressed to either B2 or B3 behavior during follow-up. Early use of thiopurine was associated with a reduced risk of behavioral progression (adjusted hazard ratio [aHR], 0.69; 95% confidence interval [CI], 0.50 to 0.90), and family history of inflammatory bowel disease was associated with an increased risk of behavioral progression (aHR, 2.29; 95% CI, 1.16 to 4.50). One hundred forty-one patients (12.0%) underwent intestinal resection, and the intestinal resection-free survival time was significantly longer in cohort 2 than in cohort 1 (p=0.003). The early use of thiopurines (aHR, 0.35;95% CI, 0.23 to 0.51) was independently associated with a reduced risk of intestinal resection. Conclusions The prognosis of CD in Korea appears to have improved over time, as evidenced by the decreasing intestinal resection rate. Early use of thiopurines was associated with an improved prognosis represented by a reduced risk of intestinal resection.

Background: Data on liver cirrhosis (LC) patients undergoing continuous renal replacement therapy (CRRT) are lacking despite the dismal prognosis. We therefore evaluated clinical characteristics and predictive factors related to mortality in LC patients undergoing CRRT. Methods: We performed a retrospective observational study at two tertiary hospitals in Korea. A total of 229 LC patients who underwent CRRT were analyzed. Patients were classified into survivor and non-survivor groups. We used multivariable Cox regression analyses to identify factors predictive of in-hospital mortality. Results: During a median follow-up of 5 days (interquartile range, 1–19 days), in-hospital mortality rate was 66.4%. In multivariable analysis, the Acute Physiology and Chronic Health Evaluation II (APACHE II) score (hazard ratio [HR], 1.03; 95% confidence interval [CI], 1.01–1.06; p = 0.02), Model for End-Stage Liver Disease (MELD) score (HR, 1.08; 95% CI, 1.04–1.11; p <0.001), and delivered CRRT dose (HR, 0.95; 95% CI, 0.92¬–0.98; p = 0.002) were significant risk factors for in-hospital mortality. Patients with a CRRT delivered dose < 25 mL/kg/hr had a higher mortality rate than those with a delivered dose > 35 mL/kg/hr (HR, 3.13; 95% CI, 1.62–6.05; p = 0.001). Subgroup analysis revealed that a CRRT delivered dose < 25 mL/kg/hr was a significant risk factor for in-hospital mortality among LC patients with a MELD score ≥ 30. Conclusion High APACHE II score, high MELD score, and low delivered CRRT dose were significant risk factors for in-hospital mortality. CRRT delivered dose impacted mortality significantly, especially in patients with a MELD score ≥ 30.

Chronic spontaneous urticaria (CSU) is defined as the occurrence of spontaneous wheals, angioedema, or both for >6 weeks in the absence of specific causes. It is a common condition associated with substantial disease burden both for affected individuals and societies in many countries, including Korea. CSU frequently persists for several years and requires high-intensity treatment; therefore, patients experience deteriorations in quality of life and medication-associated complications. During the last decade, there have been major advances in the pharmacological treatment of CSU and there is an outstanding need for evidence-based guidelines that reflect clinical practice in Korea. The guidelines reported here represent a joint initiative of the Korean Academy of Asthma, Allergy and Clinical Immunology and the Korean Dermatological Association, and aim to provide evidence-based guidance for the management of CSU in Korean adults and children. In Part 1, disease definition, guideline scope and development methodology as well as evidence-based recommendations on the use of antihistamines and corticosteroids are summarized.

Background/Aims: Although the diarrheal disease caused by Campylobacter bacteria has been continuously increasing in Korea, there has been limited study on the clinical aspects of Campylobacter enteritis in adults in Korea. The purpose of this study was to analyze the clinical features and characteristics of adult patients with Campylobacter enteritis. Methods: This retrospective study included patients diagnosed with Campylobacter enterocolitis at Nowon Eulji University Hopsital between January 2016 and December 2017. Campylobacter enterocolitis was diagnosed through polymerase chain reaction of stools from patients with acute diarrhea. Results: Among 630 hospitalized patients with acute diarrhea, Campylobacter enterocolitis was diagnosed in 88 patients (14.0%). The mean age was 37.9±19.1 years. Campylobacter enterocolitis was most prevalent in the summer (52 patients, 59.1%). Patients exhibited more than 10 times of diarrhea in 36 (40.9%), high fever above 39℃ in 19 (21.59%), and abdominal pain above 5 points on the numeric rating scale in 23 (26.14%) cases. In abdominal CT scan, pancolitis was found in 58 patients (65.9%). Small intestine was involved in 37 patients (42.4%). Mean CRP was 10.14 mg/dL (range 0.72-32.27 mg/dL). The duration of diarrhea after antibiotics treatment was 2.34±1.51 days in the ciprofloxacin treatment group and 2.26±1.71 days in the 3rd cephalosporin treatment group. Conclusions Campylobacter enterocolitis was common during summer. Commonly healthy young adults were hospitalized due to severe symptoms of Campylobacter enterocolitis. Whole colon and small bowel were frequently involved. Most patients were treated with antibiotics, and the efficacy of 3rd cephalosporin treatment was not inferior to that of ciprofloxacin treatment.

Chronic spontaneous urticaria (CSU) is defined as the occurrence of spontaneous wheals, angioedema, or both for >6 weeks in the absence of specific causes. It is a common condition associated with substantial disease burden both for affected individuals and societies in many countries, including Korea. CSU frequently persists for several years and requires high-intensity treatment; therefore, patients experience deteriorations in quality of life and medication-associated complications. During the last decade, there have been major advances in the pharmacological treatment of CSU and there is an outstanding need for evidence-based guidelines that reflect clinical practice in Korea. The guidelines reported here represent a joint initiative of the Korean Academy of Asthma, Allergy and Clinical Immunology and the Korean Dermatological Association, and aim to provide evidence-based guidance for the management of CSU in Korean adults and children. In Part 1, disease definition, guideline scope and development methodology as well as evidence-based recommendations on the use of antihistamines and corticosteroids are summarized.

Objectives: Loneliness was associated with not only social status but also general health. Psychological conditions in older people have negative effects on general health and oral health. The purpose of the study was to investigate the relationship between loneliness and subjective chewing discomfort in the elderly. Methods: This cross-sectional study analyzed the Korean Social Life, Health, and Aging Project (KSHAP) for the questionnaire, UCLA loneliness scale data of 1,511 older adults living in a rural community. Logistic regression was conducted to identify the relevance of subjective chewing discomfort in the elderly according to the level of loneliness. Results: According to the final model that after adjustment for other risk factors (age, gender, level of education, smoking, drinking, etc.), in the elderly who rarely feel loneliness group compared to the elderly who never feel loneliness was Odds ratio (OR) 1.256 (95% Confidence Interval [CI]: 0.99-1.60) and sometimes+often feel loneliness was OR 2.110 (95% CI: 1.39-3.21). Conclusions Loneliness is associated with subjective chewing discomfort in the elderly. Older people feeling loneliness are likely to have more subjective chewing discomfort.

Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) are the most severe cutaneous drug hypersensitivity reactions, which are unpredictable adverse drug reactions. SJS/TEN is associated with significant mortality and morbidity; however, effective treatment is difficult. Mesenchymal stem cells (MSCs) are well-known for their anti-inflammatory and tissue regeneration properties. The purpose of the present study was to verify whether MSCs could be applied for the treatment of SJS/TEN. We developed an SJS/TEN mouse model using peripheral blood mononuclear cells from a lamotrigine-induced SJS patient. MSCs were injected into the model to verify the treatment effect. In SJS model mice treated with MSCs, ocular damage rarely occurred, and apoptosis rate was significantly lower. We demonstrated a therapeutic effect of MSCs on SJS/TEN, with these cells presenting a potential novel therapy for the management of this disorder.

BACKGROUND: High doses of methotrexate (MTX) are often used in various chemotherapy protocols to treat acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL) in children, but its delayed elimination increases the occurrence of adverse events, such as bone marrow suppression. The aim of this study was to investigate the elimination of MTX at 24 and 48 hours. METHODS: We retrospectively analyzed electronic medical records of ALL or NHL pediatric patients who received 5 g/m² MTX infusion over 24 hours (between June, 2012 and July, 2018) at the Yonsei University Health System, Korea. The delayed elimination of MTX concentrations was assessed with 100 or 150 µM MTX at 24 hours, and 2 or 5 µM at 48 hours. RESULTS: Among the 85 MTX cycles administered, 23 cycles were classified in delayed elimination group, and 62 cycles showed normal elimination. At 24 hours, the delayed elimination group with MTX concentration > 100 µM showed higher percentage than group with MTX concentration < 100 µM (45.8% vs. 19.7%, p = 0.015). However, no differences were observed at 150 µM MTX (p = 0.66). At 48 hours, the delayed elimination was higher than the normal elimination at both concentration baselines (p < 0.001 at 2 µM, p = 0.024 at 5 µM). CONCLUSIONS: MTX concentrations greater than 100 µM show high probability of delayed elimination at 24 hours. When MTX levels are above normal, leucovorin and hydration regimens should be continued to prevent delayed elimination.
Bone Marrow ; Child ; Drug Therapy ; Electronic Health Records ; Humans ; Korea ; Leucovorin ; Lymphoma ; Lymphoma, Non-Hodgkin ; Methotrexate ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; Retrospective Studies