1.Diagnostic Accuracy of Serological Tests for Mycoplasma pneumoniae Infections in Children with Pneumonia, Based on Symptom Onset
Gahee KIM ; Ki Wook YUN ; Dayun KANG ; Taek Jin LEE ; Byung Wook EUN ; Hyunju LEE ; Yae-Jean KIM ; Doo Ri KIM ; Areum SHIN ; Hyun Mi KANG ; Ye Ji KIM ; Byung Ok KWAK ; Younghee LEE ; Ye Kyung KIM ; Young June CHOE ; Woosuck SUH ; Kyo Jin JO ; Kyung-Ran KIM ; Eun Young CHO ; Kyung Min KIM ; Joon Kee LEE ; Su Eun PARK
Annals of Laboratory Medicine 2026;46(2):162-170
Background:
Mycoplasma pneumoniae is a major cause of community-acquired pneumonia (CAP) in children, with a rising incidence of macrolide resistance. Early diagnosis is crucial for reducing the disease burden; however, current diagnostic tools have limitations.We evaluated the diagnostic accuracy of serological assays and their performance based on symptom onset in children with CAP.
Methods:
From September 2023 to September 2024, we prospectively enrolled children with CAP, classified as M. pneumoniae pneumonia (MPP) or non-MPP, from 16 hospitals in Korea. Serological testing included chemiluminescence immunoassay (CLIA) and ELISA for detecting IgM and IgG, along with particle agglutination (PA) for total antibody measurements. Serological responses were analyzed at different times after symptom onset (0–4, 5–9, and 10–21 days).
Results:
Among 472 children with CAP (362 MPP, 110 non-MPP), 138 (29.2%) underwent PA testing, and 334 (70.8%) underwent IgM testing. PA at a 1:640 cutoff showed 48.0% sensitivity and 100% specificity. CLIA and ELISA showed comparable sensitivities (69.1% vs. 69.2%) and specificities (76.9% vs. 66.7%) for IgM testing. Seropositivity increased significantly with time since symptom onset (P for trend < 0.001), reaching 97.9% for IgM, 62.5% for IgG, and 94.7% for PA at 10–21 days.
Conclusions
The time post-symptom onset significantly influenced the diagnostic utility of serological tests for pediatric MPP, which showed limited value during the early stage of illness. These findings emphasize the importance of symptom onset-based interpretation of serological test results and their utility in complementing PCR when optimizing MPP diagnosis in children.
2.A unified framework for postoperative complications after gastrectomy for gastric cancer: insights from the Korean Quality Improvement Platform in Surgery program
Jeong Ho SONG ; Chang Seok KO ; Han Hong LEE ; Hong Man YOON ; Hyoung-Il KIM ; In Gyu KWON ; Ji Yeon PARK ; Ji Yeong AN ; Jong Won KIM ; Mi Ran JUNG ; Sang-Il LEE ; Seong Ho KONG ; Sun-Hwi HWANG ; Yun-Suhk SUH ; Sang-Yong SON ; Sang-Uk HAN
Annals of Surgical Treatment and Research 2026;110(5):290-298
Purpose:
Postoperative complications following gastric cancer surgery significantly impact patient outcomes, yet standardized definitions for these events have not been consistently applied across institutions in Korea. This study aimed to develop a consensus-based, standardized complication classification system specific to gastrectomy for gastric cancer as part of the Korean Quality Improvement Platform in Surgery (K-QIPS) initiative.
Methods:
As part of K-QIPS, a dedicated task force team (TFT) was formed with surgical experts from fourteen high-volume hospitals across Korea. The TFT conducted ten formal meetings to review existing literature and international guidelines, and incorporated findings from randomized controlled trials. The final complication list was developed through expert consensus and structured into a standardized framework. A Data Entry Manual was created to support consistent data collection by surgical clinical reviewers.
Results:
The TFT defined specific postoperative complications following gastrectomy for gastric cancer, including anastomotic leakage, duodenal stump leakage, pancreatic fistula, intra-abdominal and luminal bleeding, delayed gastric emptying, and internal hernia. Notably, internal hernia was described in standardized form for the first time. General complications were developed first and overlapped in part with the gastric cancer-specific list. The task force also produced a Data Entry Manual that provides practical instructions to ensure consistency and accuracy in complication reporting.
Conclusion
This nationwide consensus initiative established the first standardized complication classification system for gastric cancer surgery in Korea. The proposed definitions and data entry system are expected to improve complication reporting, enable multicenter research, support surgical quality benchmarking, and ultimately enhance patient outcomes.
3.Comparison of cytochrome P450activity and mRNA expression in canine vs. human hepatocytes after acetaminophen, diclofenac, or valproic acid exposure
Jea Ran KANG ; Juyoung LEE ; Han Na SUH
Journal of Veterinary Science 2026;27(2):e19-
Objective:
This study aimed to examine the interspecies differences in CYP enzyme activity and mRNA expression between canine and human hepatocytes following treatment with acetaminophen (AAP), diclofenac (Dic), or valproic acid (VPA).
Methods:
We determined the 24-h exposure half-maximal inhibitory concentration (IC 50 ) values of AAP, Dic, and VPA in canine and human hepatocytes. Based on these IC 50 concentrations, we compared drug-induced alterations in various parameters, including immunocytochemistry, transcriptomic profiles (RNA-seq), and CYP activity, to assess changes at the gene and protein levels.
Results:
AAP and VPA increased CYP2J2 mRNA expression by 4.7- and 7.76-fold, respectively, whereas Dic increased CYP1A1 mRNA expression by 14.25-fold in canine hepatocytes. AAP, VPA, and Dic decreased CYP26B1 mRNA expression in canine hepatocytes by 0.03-, 0.12-, and 0.17-fold, respectively. Dic and VPA increased CYP1A1 mRNA expression by 5.53- and 6.66-fold, respectively, whereas AAP, VPA, and Dic decreased CYP4F22 mRNA expression by 0.03-, 0.13-, and 0.13-fold, respectively, in human hepatocytes.
Conclusions
and Relevance: The observed differences between species in CYP activity and mRNA levels in response to drug exposure highlight the importance of accurate and precise experimental models for the development of new medications.
4.N-acetylcysteine Restores Impaired Dentate Gyrus Neurogenesis in a Neonatal Maternal Separation Rat Model
Han-Byeol KIM ; Yu-Jin KIM ; Hyo-Min LIM ; Sang Won SUH ; Jae-Hun LEE ; C. Justin LEE ; Ran-Sook WOO
Experimental Neurobiology 2025;34(6):277-288
Early-life stress (ELS) is a major contributor to neurodevelopmental vulnerability, particularly within the dentate gyrus (DG), where oxidative burden and microglial activation disrupt adult neurogenesis. Here, we examined whether N-acetylcysteine (NAC), a cysteine prodrug and glutathione precursor, could counteract impaired neurogenesis induced by neonatal maternal separation (NMS). Adolescent NAC administration restored the number of Ki67 + proliferating progenitors and DCX + immature neurons in the DG of NMS rats, accompanied by reduced reactive oxygen species, suppressed iNOS induction, and attenuated microglial activation. NAC also normalized EAAC1 expression, indicating enhanced neuronal antioxidant capacity. Notably, NAC rescued diminished neurogenesis in EAAC1 knockout mice, demonstrating its efficacy under both stress-induced and transporter-deficient redox imbalance. These findings identify NAC as a potent modulator of hippocampal neuroplasticity, acting through the restoration of redox and inflammatory homeostasis, and support its potential as an early therapeutic strategy to mitigate long-lasting neurodevelopmental consequences of ELS.
5.Device Closure or Antithrombotic Therapy After Cryptogenic Stroke in Elderly Patients With a High-Risk Patent Foramen Ovale
Pil Hyung LEE ; Jung-Sun KIM ; Jae-Kwan SONG ; Sun U. KWON ; Bum Joon KIM ; Ji Sung LEE ; Byung Joo SUN ; Jong Shin WOO ; Soe Hee ANN ; Jung-Won SUH ; Jun Yup KIM ; Kyusup LEE ; Sang Yeub LEE ; Ran HEO ; Soo JEONG ; Jeong Yoon JANG ; Jang-Whan BAE ; Young Dae KIM ; Sung Hyuk HEO ; Jong S. KIM
Journal of Stroke 2024;26(2):242-251
Background:
and Purpose In young patients (aged 18–60 years) with patent foramen ovale (PFO)- associated stroke, percutaneous closure has been found to be useful for preventing recurrent ischemic stroke or transient ischemic attack (TIA). However, it remains unknown whether PFO closure is also beneficial in older patients.
Methods:
Patients aged ≥60 years who had a cryptogenic stroke and PFO from ten hospitals in South Korea were included. The effect of PFO closure plus medical therapy over medical therapy alone was assessed by a propensity-score matching method in the overall cohort and in those with a high-risk PFO, characterized by the presence of an atrial septal aneurysm or a large shunt.
Results:
Out of the 437 patients (mean age, 68.1), 303 (69%) had a high-risk PFO and 161 (37%) patients underwent PFO closure. Over a median follow-up of 3.9 years, recurrent ischemic stroke or TIA developed in 64 (14.6%) patients. In the propensity score-matched cohort of the overall patients (130 pairs), PFO closure was associated with a significantly lower risk of a composite of ischemic stroke or TIA (hazard ratio [HR]: 0.45; 95% confidence interval [CI]: 0.24–0.84; P=0.012), but not for ischemic stroke. In a subgroup analysis of confined to the high-risk PFO patients (116 pairs), PFO closure was associated with significantly lower risks of both the composite of ischemic stroke or TIA (HR: 0.40; 95% CI: 0.21–0.77; P=0.006) and ischemic stroke (HR: 0.47; 95% CI: 0.23–0.95; P=0.035).
Conclusion
Elderly patients with cryptogenic stroke and PFO have a high recurrence rate of ischemic stroke or TIA, which may be significantly reduced by device closure.
6.Severity-Adjusted Dexamethasone Dosing and Tocilizumab Combination for Severe COVID-19
Jin Yeong HONG ; Jae-Hoon KO ; Jinyoung YANG ; Soyoung HA ; Eliel NHAM ; Kyungmin HUH ; Sun Young CHO ; Cheol-In KANG ; Doo Ryeon CHUNG ; Jin Yang BAEK ; You Min SOHN ; Hyo Jung PARK ; Beomki LEE ; Hee Jae HUH ; Eun-Suk KANG ; Gee Young SUH ; Chi Ryang CHUNG ; Kyong Ran PECK
Yonsei Medical Journal 2022;63(5):430-439
Purpose:
Real-world experience with tocilizumab in combination with dexamethasone in patients with severe coronavirus disease (COVID-19) needs to be investigated.
Materials and Methods:
A retrospective cohort study was conducted to evaluate the effect of severity-adjusted dosing of dexamethasone in combination with tocilizumab for severe COVID-19 from August 2020 to August 2021. The primary endpoint was 30-day clinical recovery, which was defined as no oxygen requirement or referral after recovery.
Results:
A total of 66 patients were evaluated, including 33 patients in the dexamethasone (Dexa) group and 33 patients in the dexamethasone plus tocilizumab (DexaToci) group. The DexaToci group showed a statistically significant benefit in 30-day clinical recovery, compared to the Dexa group (p=0.024). In multivariable analyses, peak FiO2 within 3 days and tocilizumab combination were consistently significant for 30-day recovery (all p<0.05). The DexaToci group showed a significantly steeper decrease in FiO2 (-4.2±2.6) than the Dexa group (−2.7±2.6; p=0.021) by hospital day 15. The duration of oxygen requirement was significantly shorter in the DexaToci group than the Dexa group (median, 10.0 days vs. 17.0 days; p=0.006). Infectious complications and cellular and humoral immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the convalescence stage were not different between the two groups.
Conclusion
A combination of severity-adjusted dexamethasone and tocilizumab for the treatment of severe COVID-19 improved clinical recovery without increasing infectious complications or hindering the immune response against SARS-CoV-2.
7.Indoor pet ownership in infancy is a risk factor for the development of sensitization to pets and asthma in childhood
Sungsu JUNG ; Soo Ran NOH ; So Yeon LEE ; Jisun YOON ; Hyun Ju CHO ; Young Ho KIM ; Dong In SUH ; Song I YANG ; Ji won KWON ; Gwang Cheon JANG ; Yong Han SUN ; Sung Il WOO ; You Sook YOUN ; Kang Seo PARK ; Eun LEE ; Hwa Jin CHO ; Myung Hee KOOK ; Hye Ryoung YI ; Hai Lee CHUNG ; Ja Hyeong KIM ; Hyung Young KIM ; Jin A JUNG ; Hyang Ok WOO ; Soo Jong HONG
Allergy, Asthma & Respiratory Disease 2019;7(2):99-105
PURPOSE: It is controversial whether indoor pet exposure is either a risk or protective factor developing sensitization to pet allergens or asthma. Therefore, we investigated whether indoor pet ownership entails a risk for the development of asthma and sensitization in childhood. METHODS: The Panel Study of Korean Children (PSKC) is a general-population-based birth cohort study that recruited 2,078 mother-baby dyads in Korea between April and July of 2008. Among 1,577 children who were followed up in 2015, 559 underwent skin prick tests, spirometry and bronchial provocation tests using Provocholine. Having a cat or a dog and the prevalence of asthma were evaluated by using self-reported questionnaires and physicians’ medical records. RESULTS: During infancy, the rate of dog ownership was 4.5% (71 of 1,574) and that of cat ownership was 0.5% (8 of 1,574). Of the subjects, 7.9% (n=109) currently had at least 1 dog and 2.5% (n=34) had at least 1 cat. Pet ownership during infancy was associated with sensitization to cats or dogs (adjusted odds ratio [aOR], 4.24; 95% confidence interval [CI], 1.29–13.98), wheezing within 12 months (aOR, 5.56; 95% CI, 1.65–18.75) and current asthma (wheezing episode in the last 12 months+diagnosed asthma by physicians) (aOR, 6.36; 95% CI, 1.54–26.28). In contrast, pet ownership during the last 12 months was not associated with sensitization to cats or dogs or current asthma. CONCLUSION: Indoor pet exposure during infancy can be critical for developing sensitization to cats or dogs and asthma in childhood. Avoidance of pet exposure in early life may reduce sensitization to cats or dogs and development of asthma.
Allergens
;
Animals
;
Asthma
;
Bronchial Provocation Tests
;
Cats
;
Child
;
Cohort Studies
;
Dogs
;
Humans
;
Infant
;
Korea
;
Medical Records
;
Methacholine Chloride
;
Odds Ratio
;
Ownership
;
Parturition
;
Pets
;
Prevalence
;
Protective Factors
;
Respiratory Sounds
;
Risk Factors
;
Skin
;
Spirometry
8.Recovery Phase Spontaneous Nystagmus, Its Existence and Clinical Implication
Min Young LEE ; Hye Ran SON ; Yoon Chan RAH ; Jae Yun JUNG ; Myung Whan SUH
Journal of Audiology & Otology 2019;23(1):33-38
BACKGROUND AND OBJECTIVES: Determination of the lesion side based on the direction of the nystagmus could result in confusions to the clinicians due to mismatch between the vestibular function tests and also between vestibular and audiologic features. To minimize these mistakes, we elucidated the clinical manifestation and vestibular function test results in cases with recovery spontaneous nystagmus (rSN). SUBJECTS AND METHODS: Patients who visited ENT clinic of tertiary referral hospital for acute onset continuous vertigo from January 2008 to December 2011 were enrolled. In these patients, we assessed onset time of vertigo, time point of paralytic spontaneous nystagmus (SN) and time point of rSN. At each time point of SN, vestibular function tests and hearing function tests were performed. RESULTS: We confirmed the rSN among patients with unilateral vestibulopathy and demonstrated that high gain of the rotatory chair test (slow harmonic acceleration) and/or mismatch of the SN direction and contralateral caloric weakness could indicate the recovery state of patients and nystagmus observed in this stage is recovery phase nystagmus. CONCLUSIONS: In acute vestibulopathy patients, recovery phase nystagmus was observed and on this stage of disease vestibular function tests shows several features that could predict recovery state.
Hearing
;
Humans
;
Tertiary Care Centers
;
Vertigo
;
Vestibular Function Tests
9.Transaminase Changes in Korean Rheumatoid Arthritis Patients with Chronic Hepatitis C after Biologic Therapy.
Hyun Mi KWON ; Kichul SHIN ; Jin Young MOON ; Shin Seok LEE ; Won Tae CHUNG ; Jisoo LEE ; Sang Heon LEE ; Seong Wook KANG ; Chang Hee SUH ; Seung Jae HONG ; Ran SONG ; Jung Yoon CHOE ; Yeong Wook SONG
Journal of Rheumatic Diseases 2018;25(2):108-115
OBJECTIVE: Coexisting chronic hepatitis C can be problematic when treating rheumatoid arthritis (RA). This study examined the changes in the transaminase and viral load in hepatitis C virus (HCV)-infected RA patients after initiating biologic agents. METHODS: A multicenter retrospective study was conducted at 12 University Hospitals in Korea between November 2014 and November 2015, and 78 RA patients, who met the 2010 American College of Rheumatology and European League Against Rheumatism classification criteria for RA and were concomitantly infected with HCV, were identified. The baseline and longitudinal clinical data, changes in liver function, and viral RNA titers were evaluated. RESULTS: Seventeen (21.8%) patients were treated with biologic agents, including etanercept (n=8), adalimumab (n=8), infliximab (n=2), tocilizumab (n=2), abatacept (n=1), and golimumab (n=1) (median 1.5 patient-years). Four patients experienced marked increases in transaminase during treatment with adalimumab (n=2) and tocilizumab (n=2). Two patients (one using adalimumab, the other using tocilizumab) were treated with anti-viral agents and showed dramatic improvement in both the viral RNA and transaminase. One patient discontinued adalimumab due to the repeated elevated transaminase levels along with a twofold increase in the viral RNA titer, and the transaminase level subsequently normalized. No case of overt viral reactivation was identified. CONCLUSION: The data support that changes in transaminase and/or viral load associated with biologic agents in HCV-infected RA patients are possible. Therefore, the liver function and viral RNA titer should be followed regularly during biologic therapy.
Abatacept
;
Adalimumab
;
Antirheumatic Agents
;
Arthritis, Rheumatoid*
;
Biological Factors
;
Biological Therapy*
;
Classification
;
Etanercept
;
Hepacivirus
;
Hepatitis C
;
Hepatitis C, Chronic*
;
Hepatitis, Chronic*
;
Hospitals, University
;
Humans
;
Infliximab
;
Korea
;
Liver
;
Retrospective Studies
;
Rheumatic Diseases
;
Rheumatology
;
RNA, Viral
;
Viral Load
10.Gastrointestinal Risk Factors and Non-steroidal Anti-inflammatory Drugs Use in Rheumatoid Arthritis and Osteoarthritis Patients in Korea.
Eun Young LEE ; Seung Jae HONG ; Yong Beom PARK ; Kyung Su PARK ; Chan Bum CHOI ; Chang Keun LEE ; Ran SONG ; Yun Jong LEE ; Chang Hee SUH ; Hyun Ah KIM ; Jun Ki MIN ; Chong Hyeon YOON ; Won PARK ; Won Tae CHUNG ; Geun Tae KIM ; Jung Yoon CHOE ; Seong Wook KANG ; Yong Wook PARK ; Wan Hee YOO ; Sang Heon LEE
Journal of Rheumatic Diseases 2016;23(1):47-54
OBJECTIVE: The aim of this study was to examine and compare the gastrointestinal (GI) risk factors and treatment patterns of rheumatoid arthritis (RA) and osteoarthritis (OA) patients in Korea. METHODS: This was a cross-sectional, observational study on RA and OA patients taking non-steroidal anti-inflammatory drugs (NSAIDs) for at least 1 month. A total of 1,896 patients (981 RA patients, 915 OA patients) were recruited from 20 university hospitals. Data were collected through medical records and patient surveys. GI risk factors included age, prolonged (over 3 months) or high-dose use of NSAIDs, alcohol drinking, smoking, use of aspirin, anticoagulants or glucocorticoids, comorbidities, and history of Helicobacter pylori infection or other GI complications. Treatment patterns were classified according to groups using, selective cyclooxygenase (COX)-2 inhibitors+/-gastro-protective agents, non-selective COX-2 inhibitors+proton pump inhibitor, or non-selective COX-2 inhibitors+/-other gastro-protective agents. RESULTS: GI risk factors were highly present in both RA and OA patients. The proportion of prolonged use of NSAIDs, smoking, and glucocorticoid use were higher in RA patients (p<0.001). The proportion of comorbidities and use of aspirin were higher in OA patients (p<0.001). The remaining GI risk factors were present in similar proportions in both groups. Use of selective COX-2 inhibitors or gastro-protective agents was higher in RA patients. CONCLUSION: Prolonged use of NSAIDs and concomitant glucocorticoid use were higher in RA patients, while comorbidities and concomitant aspirin use were predominant in OA patients. These results will provide insights for use in development of future guidelines for proper selection of NSAIDs and effective prevention of GI complications in arthritis patients.
Alcohol Drinking
;
Anti-Inflammatory Agents, Non-Steroidal
;
Anticoagulants
;
Arthritis
;
Arthritis, Rheumatoid*
;
Aspirin
;
Comorbidity
;
Cyclooxygenase 2 Inhibitors
;
Glucocorticoids
;
Helicobacter pylori
;
Hospitals, University
;
Humans
;
Korea*
;
Medical Records
;
Observational Study
;
Osteoarthritis*
;
Prostaglandin-Endoperoxide Synthases
;
Risk Factors*
;
Smoke
;
Smoking

Result Analysis
Print
Save
E-mail