Background: Research is continuously being conducted on the relationship between the airway and malocclusion. The nose, asthe upper part of the respiratory pathway, plays a critical role. While various international studies employ the Nasal Index classification for nasal morphology, domestic research remains scarce. This research investigates the proportions of nasal morphology in malocclusion patients utilizing a 3D software. Methods: The study evaluated 100 malocclusion patients in their 20s (40 Class I, 34 Class II, 26 Class III). Cone-beam computedtomography was used with the Mimics (ver. 22; Materialise) 3D program to model the skull and soft tissues of the patients in three views: coronal, sagittal, and frontal. Results: The results showed that in Class I, there were 5 leptorrhine (long and narrow) cases, 30 mesorrhine (moderate shape)cases, and 5 platyrrhine (broad and short) cases. In Class II, there were 3 leptorrhine, 25 mesorrhine, and 6 platyrrhine cases.In Class III, there were 2 leptorrhine, 21 mesorrhine, and 3 platyrrhine cases. Conclusion The findings of this study indicate that there is no significant correlation between the size of the nose and malocclusionin patients. Additionally, additional research related to this study is expected to be necessary.

Background/Aims: Although endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) and fine needle biopsy (FNB) are widely used for tissue acquisition of pancreatic solid mass, the optimal strategy of this procedure has not been established yet. The aim of this nationwide study was to investigate the current practice patterns of EUS-FNA/FNB for pancreatic solid mass in Korea. Methods: The Policy-Quality Management of the Korean Pancreatobiliary Association (KPBA) developed a questionnaire containing 22 questions. An electronic survey consisting of the questionnaire was distributed by e-mail to members registered to the KPBA. Results: A total of 101 respondents completed the survey. Eighty respondents (79.2%) performed preoperative EUS-FNA/FNB for operable pancreatic solid mass. Acquire needles (60.4%) were used the most, followed by ProCore needles (47.5%). In terms of need size, most respondents (>80%) preferred 22-gauge needles regardless of the location of the mass. Negative suction with a 10-mL syringe (71.3%) as sampling technique was followed by stylet slow-pull (41.6%). More than three needle passes for EUS-FNA/FNB was performed by most respondents (>80%). The frequency of requiring repeated procedure was significantly higher in respondents with a low individual volume (<5 per month, p=0.001). Prophylactic antibiotics were routinely used in 39 respondents (38.6%); rapid on-site pathologic evaluation was used in 6.1%. Conclusions According to this survey, practices of EUS-FNA/FNB for pancreatic solid mass varied substantially, some of which differed considerably from the recommendations present in existing guidelines. These results suggest that the development of evidence-based quality guidelines fitting Korean clinical practice is needed to establish the optimal strategy for this procedure.

Background/Aims: Low-volume preparations for colonoscopy are gaining attention for their higher acceptability. However, the efficacy and safety of oral sulfate solution (OSS) preparations in patients with ulcerative colitis (UC) has not been well known. Therefore, we aimed to compare OSS and 2-L polyethylene glycol with ascorbic acid (PEG+Asc) for bowel preparation in inactive UC. Methods: A multicenter, randomized, single-blind study was conducted at six tertiary referral hospitals in Korea. Outpatients with UC who had stable disease activity were randomly allocated to the OSS group or the 2-L PEG+Asc group for bowel preparation before colonoscopy. The study outcomes included treatment efficacy, safety, tolerability, and acceptability. Bowel cleansing was assessed using the Boston Bowel Preparation Scale and rated as successful cleansing if the score was ≥6. Patient acceptance and tolerability were assessed using a 4-point ordinal scale. Additionally, disease activity and laboratory data before and after colonoscopy were evaluated to check for safety. Results: The OSS and 2-L PEG+Asc groups included 92 and 93 participants, respectively. No significant between-group difference was noted in successful cleansing (OSS [96.7%] vs 2-L PEG+Asc [97.8%], p=0.64). Moreover, the safety, acceptance, and tolerability were not significantly different (all p>0.05). Furthermore, no significant changes were found in serum electrolytes or disease activity in either group. Conclusions OSS is effective for colonoscopy cleansing, has acceptable tolerability, and does not affect disease activity; thus, it can be used safely for bowel preparation in patients with inactive UC.

Background: Targeted risk population has been highly vaccinated against pneumococcal diseases in South Korea. Despite this, the pneumococcal serotype distribution is evolving, which impedes efficient roll-out of vaccines. Methods: This prospective cohort study included patients aged ≥ 19 years with communityacquired pneumonia (CAP) from five university hospitals in South Korea between September 2018 and July 2021. The outcomes of interest were the demographic and clinical characteristics of patients with CAP, pneumococcal serotype distribution, and risk factors of 30-day mortality in patients with pneumococcal CAP (pCAP). Considering the high seroprevalence, we analyzed the clinical characteristics of serotype 3 pCAP. Results: A total of 5,009 patients hospitalized with CAP was included (mean age ± standard deviation, 70.3 ± 16.0 years; 3,159 [63.1%] men). Streptococcus pneumoniae was the leading causative agent of CAP (11.8% overall, 17.7% in individuals aged < 65 years with chronic medical conditions). Among the 280 serotyped Streptococcus pneumococcus, serotype 3 was the most common (10.0%), followed by serotypes 19A (8.9%), 34 (8.9%), and 35B (8.9%).Non-vaccine serotypes (serotype 35B [13.9%] and 34 [12.0%]) were the most prevalent in 108 individuals vaccinated with 23-valent pneumococcal polysaccharide vaccine (PPSV23).Serotype 3 was prevalent, irrespective of PPSV23 vaccination status, and more common in individuals with chronic lung disease (P = 0.008). Advanced age (adjusted odds ratio [aOR], 1.040; 95% confidence interval [CI], 1.011–1.071), long-term care facility residence (aOR, 2.161; 95% CI, 1.071–4.357), and bacteremia (aOR, 4.193; 95% CI, 1.604–10.962) were independent risk factors for 30-day mortality in patients with pCAP. PPSV23 vaccination reduced the risk of mortality (aOR, 0.507; 95% CI, 0.267–0.961). Conclusion Serotype 3 and 19A were still the most common serotypes of pCAP in South Korea despite the national immunization program of 13-valent pneumococcal conjugated vaccine in children and PPSV23 in old adults. PPSV23 vaccination might reduce the risk of mortality in patients with pCAP.

Background: Point-of-care testing (POCT) coagulometers are increasingly used for monitoring warfarin therapy. However, in high international normalized ratio (INR) ranges, significant discrepancy in the INR between POCT and conventional laboratory tests occurs. We compared the INR of POCT (CoaguChek XS Plus; Roche Diagnostics, Mannheim, Germany) with that of a conventional laboratory test (ACL TOP 750; Instrumentation Laboratory SpA, Milan, Italy) and explored possible reasons for discrepancy. Methods: Paired POCT and conventional laboratory test INRs were analyzed in 400 samples from 126 patients undergoing warfarin therapy after cardiac surgery. Coagulation factor and thrombin generation tests were compared using the Mann–Whitney U test. Correlations between coagulation factors and INRs were determined using Pearson correlation coefficients. Results: The mean difference in the INR between the tests increased at high INR ranges. Endogenous thrombin potential levels were decreased at INR <2.0 for CoaguChek XS Plus and 2.0< INR <3.0 for ACL TOP 750 compared with those at INR <2.0 for both tests, indicating a better performance of ACL TOP 750 in assessing thrombin changes. The correlation coefficients of coagulation factors were stronger for ACL TOP 750 INR than for CoaguChek XS Plus INR. Vitamin K-dependent coagulation factors were found to contribute to the INR discrepancy. Conclusions Decreases in vitamin K-dependent coagulation and anticoagulation factors can explain the significant discrepancy between the two tests in high INR ranges. Since conventional laboratory test INR values are more reliable than POCT INR values, a confirmatory conventional laboratory test is required for high INR ranges.

Objective: This study aimed to investigate the characteristics of the high-risk group for dental caries among 12- and 15-year-old children in Laos. Methods: Oral health survey was conducted on 12-year-old (N=537) and 15-year-old (N=490) children in Laos. The oral examination data were listed from highest to highest based on the permanent caries experience index. Then the caries experience permanent index of the participants corresponding to the top third was calculated. In the final high-risk group, 179 and 163 children aged 12 and 15 years, respectively, were analyzed for the Significant Caries (SiC) Index. Results: The Decayed, Missing and Filled Teeth (DMFT) index of 12-year-old children in Laos was 1.59 (urban area 1.72, rural area 1.46), and the SiC index of the high-risk group for dental caries was 3.93 (urban area 4.01, rural area 3.85). DMFT index of the 15-year-old group was 2.04 (2.37 in urban areas, 1.74 in rural areas), and the SiC index of the high-risk group for dental caries was 5.17 (5.90 in urban areas, 4.49 in rural areas). Conclusions Children aged 12 and 15 in the high-risk group for dental caries in Laos showed a higher caries experience permanence index than the overall average in the high-risk group. Based on the outcome of the investigation that the high-risk group had a lot of experience with dental caries, it is thought that the priority dental caries prevention project for the high-risk group of dental caries should be carried out.

Purpose: To evaluate the role of postmastectomy radiation therapy (PMRT) in patients with node-negative breast cancer of 5cm or larger tumors undergoing mastectomy Materials and Methods: Medical records of 274 patients from 18 institutions treated with mastectomy between January 2000 and December 2016 were retrospectively reviewed. Among these, 202 patients underwent PMRT, while 72 did not. Two hundred and forty-one patients (88.0%) received systemic chemotherapy, and 172 (62.8%) received hormonal therapy. Patients receiving PMRT were younger, more likely to have progesterone receptor-positive tumors, and received adjuvant chemotherapy more frequently compared with those without PMRT (p <0.001, 0.018, and <0.001, respectively). Other characteristics were not significantly different between the two groups. Results: With a median follow-up of 95 months (range, 1-249), there were 9 locoregional recurrences, and 20 distant metastases. The 8-year locoregional recurrence-free survival rates were 98.0% with PMRT and 91.3% without PMRT (p=0.133), and the 8-year disease-free survival (DFS) rates were 91.8% with PMRT and 73.9% without PMRT (p=0.008). On multivariate analysis incorporating age, histologic grade, lymphovascular invasion, hormonal therapy, chemotherapy, and PMRT, the absence of lymphovascular invasion and the receipt of PMRT were associated with improved DFS (p=0.025 and 0.009, respectively). Conclusion Locoregional recurrence rate was very low in node-negative breast cancer of 5cm or larger tumors treated with mastectomy regardless of the receipt of PMRT. However, PMRT was significantly associated with improved DFS. Further investigation is needed to confirm these findings.

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.

During the 2019 domestic measles outbreak in Korea, measles occurred in healthcare workers with two doses of the measles, mumps and rubella vaccine, and the strict application of the Occupational Safety and Health Act required medical institutions to identify healthcare workers' immunity to measles and vaccinate the susceptible pockets. In response to the frontline medical institutions' request to review the measles recommendations and guidelines, the Korean Society of Infectious Diseases held a roundtable discussion on the causes of measles outbreak, timing of vaccinations, antibody tests, and booster vaccinations for healthcare workers, and financial support from the government and municipality as well as response strategies against the outbreak in healthcare settings. In Korea, the seroprevalence of measles is decreasing in the vaccine-induced immunity group during the maintenance of measles elimination over several years. The susceptible group against measles is in their 20s and 30s, and this may be because of waning immunity rather than nonresponse considering Korea's vaccine policy. The risk of measles nosocomial infection from community increases as these susceptible pockets actively engage in medical institutions.Thus, data on the immunity of low seroprevalence group in Korea are needed, further discussion is needed on the booster vaccination based on the data. Especially, antibody testing and vaccination in healthcare workers may be necessary to prevent the spread of measles in medical insutitutions, and further discussion is needed regarding specific testing methods, and the timing and frequency of test and vaccination.

Objectives: The aim of this study was to determine the dental caries experience of children in Laos. Methods: Oral examinations were performed on a total of 1,540 students in 513 primary school students, 537 middle school students, and 490 high school students and the results analyzed. Results: The dft index (decayed-filled primary teeth index) of 6-year-old primary school children was 6.04. The DMFT index (decayed-filled-missing permanent teeth index) was 1.59 in 12-yearold middle school children and 2.04 in 15-year-old middle school children. Conclusions Caries experience in most of the age groups was on the high side. It is considered that in Laos, a treatment project to stop the progression of caries is necessary in parallel with a prevention project to lower the caries fatality rate.