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.

Objective: Research on fetal mortality due to congenital anomalies is insufficient, particularly that utilizing data specific to South Korea. Thus, we aimed to investigate the characteristics and risk factors for fetal death due to congenital anomalies in Korea. Methods: Fetal deaths registered from 2009-2020 with Statistics Korea were assessed. Fetal charac teristics included gestational age, body weight, sex, and multiple fetuses, while maternal characteri stics included age, educational level, nationality, and place of residence. Risk factors for fetal death were analyzed using simple comparison and logistic regression. Changes in fetal mortality by year were examined using Poisson regression analysis. Results: A total of 37,928 fetal deaths occurred, among which 3,758 were classified as congenital anomaly, 710 as non-congenital anomaly, and 33,460 as unknown cause. Fetal mortality for gesta tional weeks 20 to 27 and ≥28 were 75.3% and 24.7%, respectively. The proportion of congenital anomalies among fetal deaths during these gestational age periods is 11.3% and 5.8%. Multiple fetuses, maternal age of <20 years or ≥40 years were identified as risk factors for fetal death due to congenital anomalies. Among the top 30 causes, covering 97.5% of all deaths, unspecified causes were 88.2%, congenital malformations 8.2%, and other causes 2.0%, respectively. Fetal mortality and deaths from congenital anomalies exhibited downward trends. Conclusion Fetal deaths due to congenital anomalies showed a decreasing trend, but the risks, such as multiple fetuses and advanced maternal age are increasing in Korea. Therefore, careful monitoring of fetal deaths due to congenital anomalies are essential.

Objective: Research on fetal mortality due to congenital anomalies is insufficient, particularly that utilizing data specific to South Korea. Thus, we aimed to investigate the characteristics and risk factors for fetal death due to congenital anomalies in Korea. Methods: Fetal deaths registered from 2009-2020 with Statistics Korea were assessed. Fetal charac teristics included gestational age, body weight, sex, and multiple fetuses, while maternal characteri stics included age, educational level, nationality, and place of residence. Risk factors for fetal death were analyzed using simple comparison and logistic regression. Changes in fetal mortality by year were examined using Poisson regression analysis. Results: A total of 37,928 fetal deaths occurred, among which 3,758 were classified as congenital anomaly, 710 as non-congenital anomaly, and 33,460 as unknown cause. Fetal mortality for gesta tional weeks 20 to 27 and ≥28 were 75.3% and 24.7%, respectively. The proportion of congenital anomalies among fetal deaths during these gestational age periods is 11.3% and 5.8%. Multiple fetuses, maternal age of <20 years or ≥40 years were identified as risk factors for fetal death due to congenital anomalies. Among the top 30 causes, covering 97.5% of all deaths, unspecified causes were 88.2%, congenital malformations 8.2%, and other causes 2.0%, respectively. Fetal mortality and deaths from congenital anomalies exhibited downward trends. Conclusion Fetal deaths due to congenital anomalies showed a decreasing trend, but the risks, such as multiple fetuses and advanced maternal age are increasing in Korea. Therefore, careful monitoring of fetal deaths due to congenital anomalies are essential.

Objective: Research on fetal mortality due to congenital anomalies is insufficient, particularly that utilizing data specific to South Korea. Thus, we aimed to investigate the characteristics and risk factors for fetal death due to congenital anomalies in Korea. Methods: Fetal deaths registered from 2009-2020 with Statistics Korea were assessed. Fetal charac teristics included gestational age, body weight, sex, and multiple fetuses, while maternal characteri stics included age, educational level, nationality, and place of residence. Risk factors for fetal death were analyzed using simple comparison and logistic regression. Changes in fetal mortality by year were examined using Poisson regression analysis. Results: A total of 37,928 fetal deaths occurred, among which 3,758 were classified as congenital anomaly, 710 as non-congenital anomaly, and 33,460 as unknown cause. Fetal mortality for gesta tional weeks 20 to 27 and ≥28 were 75.3% and 24.7%, respectively. The proportion of congenital anomalies among fetal deaths during these gestational age periods is 11.3% and 5.8%. Multiple fetuses, maternal age of <20 years or ≥40 years were identified as risk factors for fetal death due to congenital anomalies. Among the top 30 causes, covering 97.5% of all deaths, unspecified causes were 88.2%, congenital malformations 8.2%, and other causes 2.0%, respectively. Fetal mortality and deaths from congenital anomalies exhibited downward trends. Conclusion Fetal deaths due to congenital anomalies showed a decreasing trend, but the risks, such as multiple fetuses and advanced maternal age are increasing in Korea. Therefore, careful monitoring of fetal deaths due to congenital anomalies are essential.

Background and Objectives: Kawasaki disease (KD) is an acute vasculitis that primarily affects children under age 5 years. Approximately 20–25% of untreated children with KD and 3–5% of those treated with intravenous immunoglobulin therapy develop coronary artery aneurysms (CAAs). The prevalence of CAAs is much higher in male than in female patients with KD, but the underlying factors contributing to susceptibility to CAAs in patients with KD remain unclear. This study aimed to identify sex-specific susceptibility loci associated with CAAs in KD patients. Methods: A sex-stratified genome-wide association study (GWAS) was performed using previously obtained GWAS data from 296 KD patients and a new replication study in an independent set of 976 KD patients by comparing KD patients without CAA (controls) and KD patients with aneurysms (internal diameter ≥5 mm) (cases). Results: Six male-specific susceptibility loci, PDE1C, NOS3, DLG2, CPNE8, FUNDC1, and GABRQ (odds ratios [ORs], 2.25–9.98; p=0.00204–1.96×10−6 ), and 2 female-specific susceptibility loci, SMAD3 (OR, 4.59; p=0.00016) and IL1RAPL1 (OR, 4.35; p=0.00026), were significantly associated with CAAs in patients with KD. In addition, the numbers of CAA risk alleles additively contributed to the development of CAAs in patients with KD. Conclusions A sex-stratified GWAS identified 6 male-specific (PDE1C, NOS3, DLG2, CPNE8, FUNDC1, and GABRQ) and 2 female-specific (SMAD3 and IL1RAPL1) CAA susceptibility loci in patients with KD.

Background and Objectives: Kawasaki disease (KD) is an acute vasculitis that primarily affects children under age 5 years. Approximately 20–25% of untreated children with KD and 3–5% of those treated with intravenous immunoglobulin therapy develop coronary artery aneurysms (CAAs). The prevalence of CAAs is much higher in male than in female patients with KD, but the underlying factors contributing to susceptibility to CAAs in patients with KD remain unclear. This study aimed to identify sex-specific susceptibility loci associated with CAAs in KD patients. Methods: A sex-stratified genome-wide association study (GWAS) was performed using previously obtained GWAS data from 296 KD patients and a new replication study in an independent set of 976 KD patients by comparing KD patients without CAA (controls) and KD patients with aneurysms (internal diameter ≥5 mm) (cases). Results: Six male-specific susceptibility loci, PDE1C, NOS3, DLG2, CPNE8, FUNDC1, and GABRQ (odds ratios [ORs], 2.25–9.98; p=0.00204–1.96×10−6 ), and 2 female-specific susceptibility loci, SMAD3 (OR, 4.59; p=0.00016) and IL1RAPL1 (OR, 4.35; p=0.00026), were significantly associated with CAAs in patients with KD. In addition, the numbers of CAA risk alleles additively contributed to the development of CAAs in patients with KD. Conclusions A sex-stratified GWAS identified 6 male-specific (PDE1C, NOS3, DLG2, CPNE8, FUNDC1, and GABRQ) and 2 female-specific (SMAD3 and IL1RAPL1) CAA susceptibility loci in patients with KD.

Background and Objectives: Kawasaki disease (KD) is an acute vasculitis that primarily affects children under age 5 years. Approximately 20–25% of untreated children with KD and 3–5% of those treated with intravenous immunoglobulin therapy develop coronary artery aneurysms (CAAs). The prevalence of CAAs is much higher in male than in female patients with KD, but the underlying factors contributing to susceptibility to CAAs in patients with KD remain unclear. This study aimed to identify sex-specific susceptibility loci associated with CAAs in KD patients. Methods: A sex-stratified genome-wide association study (GWAS) was performed using previously obtained GWAS data from 296 KD patients and a new replication study in an independent set of 976 KD patients by comparing KD patients without CAA (controls) and KD patients with aneurysms (internal diameter ≥5 mm) (cases). Results: Six male-specific susceptibility loci, PDE1C, NOS3, DLG2, CPNE8, FUNDC1, and GABRQ (odds ratios [ORs], 2.25–9.98; p=0.00204–1.96×10−6 ), and 2 female-specific susceptibility loci, SMAD3 (OR, 4.59; p=0.00016) and IL1RAPL1 (OR, 4.35; p=0.00026), were significantly associated with CAAs in patients with KD. In addition, the numbers of CAA risk alleles additively contributed to the development of CAAs in patients with KD. Conclusions A sex-stratified GWAS identified 6 male-specific (PDE1C, NOS3, DLG2, CPNE8, FUNDC1, and GABRQ) and 2 female-specific (SMAD3 and IL1RAPL1) CAA susceptibility loci in patients with KD.

Background/Aims: The Gout Impact Scale (GIS), a part of the Gout Assessment Questionnaire 2.0, is used to measure gout-specific health-related quality of life (HRQOL). Although several studies have been conducted on the factors affecting the HRQOL of patients with gout, few have focused on lifestyle factors. This study aimed to investigate the correlation between lifestyle habits and HRQOL using the GIS in patients with gout. Methods: We used data from the Urate-Lowering TheRApy in Gout (ULTRA) registry, a prospective cohort of Korean patients with gout treated at multiple centers nationwide. The patients were aged ≥18 years and met the 2015 American College of Rheumatology/European League Against Rheumatism gout classification criteria. They were asked to complete a GIS and questions regarding their lifestyle habits at enrollment. Results: The study included 232 patients. ‘Gout concern overall’ scores in the GIS were significantly lower in patients who exercised more frequently and consumed soft drinks and meat less, and ‘well-being during attack’ scores were significantly lower in patients who consumed vegetables and exercised more frequently. The frequency of vegetable consumption had a negative linear relationship with the ‘well-being during attack’ and ‘gout concern during attack’ scores (p = 0.01, p = 0.001, respectively). The frequency of exercise had a negative linear relationship with the ‘gout concern overall’ and ‘gout concern during attack’ scores (p = 0.04 and p = 0.002, respectively). Conclusions Patients with gout who frequently consumed vegetables and exercised regularly experienced less impact of gout, exhibiting a better GIS that represented HRQOL.

Objective: Research on fetal mortality due to congenital anomalies is insufficient, particularly that utilizing data specific to South Korea. Thus, we aimed to investigate the characteristics and risk factors for fetal death due to congenital anomalies in Korea. Methods: Fetal deaths registered from 2009-2020 with Statistics Korea were assessed. Fetal charac teristics included gestational age, body weight, sex, and multiple fetuses, while maternal characteri stics included age, educational level, nationality, and place of residence. Risk factors for fetal death were analyzed using simple comparison and logistic regression. Changes in fetal mortality by year were examined using Poisson regression analysis. Results: A total of 37,928 fetal deaths occurred, among which 3,758 were classified as congenital anomaly, 710 as non-congenital anomaly, and 33,460 as unknown cause. Fetal mortality for gesta tional weeks 20 to 27 and ≥28 were 75.3% and 24.7%, respectively. The proportion of congenital anomalies among fetal deaths during these gestational age periods is 11.3% and 5.8%. Multiple fetuses, maternal age of <20 years or ≥40 years were identified as risk factors for fetal death due to congenital anomalies. Among the top 30 causes, covering 97.5% of all deaths, unspecified causes were 88.2%, congenital malformations 8.2%, and other causes 2.0%, respectively. Fetal mortality and deaths from congenital anomalies exhibited downward trends. Conclusion Fetal deaths due to congenital anomalies showed a decreasing trend, but the risks, such as multiple fetuses and advanced maternal age are increasing in Korea. Therefore, careful monitoring of fetal deaths due to congenital anomalies are essential.

Objective: Research on fetal mortality due to congenital anomalies is insufficient, particularly that utilizing data specific to South Korea. Thus, we aimed to investigate the characteristics and risk factors for fetal death due to congenital anomalies in Korea. Methods: Fetal deaths registered from 2009-2020 with Statistics Korea were assessed. Fetal charac teristics included gestational age, body weight, sex, and multiple fetuses, while maternal characteri stics included age, educational level, nationality, and place of residence. Risk factors for fetal death were analyzed using simple comparison and logistic regression. Changes in fetal mortality by year were examined using Poisson regression analysis. Results: A total of 37,928 fetal deaths occurred, among which 3,758 were classified as congenital anomaly, 710 as non-congenital anomaly, and 33,460 as unknown cause. Fetal mortality for gesta tional weeks 20 to 27 and ≥28 were 75.3% and 24.7%, respectively. The proportion of congenital anomalies among fetal deaths during these gestational age periods is 11.3% and 5.8%. Multiple fetuses, maternal age of <20 years or ≥40 years were identified as risk factors for fetal death due to congenital anomalies. Among the top 30 causes, covering 97.5% of all deaths, unspecified causes were 88.2%, congenital malformations 8.2%, and other causes 2.0%, respectively. Fetal mortality and deaths from congenital anomalies exhibited downward trends. Conclusion Fetal deaths due to congenital anomalies showed a decreasing trend, but the risks, such as multiple fetuses and advanced maternal age are increasing in Korea. Therefore, careful monitoring of fetal deaths due to congenital anomalies are essential.