鈴木 孝典

BACKGROUND: Kawasaki disease (KD) onset has been suggested to be associated with infections and various environmental factors. However, research on whether the delivery type plays a role in KD development is limited. This study investigated whether cesarean section (CS) or vaginal delivery (VD) is associated with KD onset using a large administrative claims database in Japan. METHOD: We conducted a case-control study using the JMDC Claims Database from January 2005 to December 2021. Data on children born via CS or VD and their mothers were collected. KD patients were identified from the source population, and controls without KD were randomly selected based on sex, age and registration time, each matched to 4 controls using a risk-set sampling technique. We analyzed the association between delivery type and KD onset using multivariate conditional logistic regression, defining KD as the primary outcome based on specific criteria. RESULTS: Case-control matching created 3363 pairs of cases (n = 3363) and controls (n = 13,363). The proportions of CS, maternal age, Charlson Comorbidity Index, presence of older siblings and low birth weight infants were significantly different between the cases and controls. In the multivariate analysis, KD onset was associated with CS [odds ratio (OR): 1.12; 95% confidence interval (CI): 1.02-1.24], the presence of older siblings (OR: 1.11; 95% CI: 1.02-1.21), lower birth weight (1001-2500 g) (OR: 1.22; 95% CI: 1.04-1.43) and antibiotic use (OR: 1.12; 95% CI: 1.02-1.24). CONCLUSIONS: The risk of developing KD may be influenced by the delivery type (CS or VD), the presence of older siblings, low birth weight and antibiotic use.

The most effective dosage of intravenous immunoglobulin (IVIG) to prevent coronary artery abnormalities (CAAs) in patients with acute Kawasaki disease (KD) remains unknown. This study aimed to identify the appropriate dose of IVIG to be administered to patients with acute KD, using a national inpatient database in Japan. We used the Diagnostic Procedure Combination database to identify KD patients treated with IVIG between 2010 and 2020. The primary outcome was the proportion of CAAs upon discharge. Secondary outcomes included IVIG resistance, length of stay, and medical costs. Data from 88,223 patients were extracted from the database. We found a U-shaped association between IVIG dose and the proportion of CAA, with the bottom of the curve at approximately 2.0 g/kg; the odds ratio (95% confidence interval [CI]) was 1.34 (1.26-1.43) for 1.8 g/kg and 1.80 (1.29-2.51) for 2.4 g/kg with reference to 2.0 g/kg for CAA. Similarly, IVIG dose had a U-shaped association with the proportion of IVIG resistance, with the bottom of the curve at approximately 2.0 g/kg; the odds ratio (95% CI) was 1.39 (1.36-1.42) for 1.8 g/kg and 8.95 (8.15-9.83) for 2.4 g/kg with reference to 2.0 g/kg for IVIG resistance. Additionally, IVIG dosage was found to have U-shaped associations with the length of stay and medical costs, with the bottom of the curve at approximately 2 g/kg.   Conclusions: IVIG with a dose of 2 g/kg was considered appropriate for the initial treatment of KD. What is Known: • For treatments of acute Kawasaki Disease (KD), IVIG has been the most recommended to reduce fever early and prevent complications of CAAs. Few studies have shown the most effective dosage of IVIG to be administered to prevent CAAs. What is New: • 2 g/kg intravenous immunoglobulin was considered appropriate for the initial treatment of Kawasaki disease.

UNLABELLED: We describe the case of a young patient with atresia of the right coronary arterial ostium with left ventricular fistula. This was suspected from the abnormality detected on a 12‑lead electrocardiogram (ECG) during a school examination at the time of admission to junior high school and echocardiography findings. This disease may occur due to abnormalities in several molecules that are essential for coronary artery development. In cases of ECG abnormality, and unexplained aortic valve regurgitation and coronary artery abnormalities on echocardiography are detected, this disease should be suspected. LEARNING OBJECTIVE: Coronary artery anomalies have been identified in coronary angiograms. Herein, we describe the case of a young patient with atresia of the right coronary arterial ostium with left ventricular fistula. This disease may be caused by abnormalities in several molecules that are essential molecule for coronary artery development.

PURPOSE: Few studies have compared the effects of low-concentration (5%) and high-concentration (10%) intravenous immunoglobulin (IVIG) preparations for patients with Kawasaki disease (KD) in the acute phase. The purpose of this study was to compare outcomes between low- and high-concentration IVIG preparations in children with KD, using a national inpatient database in Japan. METHOD: We used the Diagnostic Procedure Combination database to identify patients with KD treated with IVIG from April 2012 to March 2020. We identified those receiving high- and low-concentration IVIG preparations as an initial treatment. The outcomes included the proportions of patients with coronary artery abnormalities (CAAs) and IVIG resistance, length of stay, and medical costs. Propensity score-matched analyses were conducted to compare the outcomes between the 2 groups. Instrumental variable analyses were performed to confirm the results. RESULT: We identified 48 046 patients with KD and created 4:1 propensity score-matched pairs between the low- and high-concentration IVIG groups. There was a significant difference in the percentage with IVIG resistance between the 2 groups (20.6% vs 24.1%; risk difference, 3.5% [95% confidence interval, 2.3-4.7]; P < .001). However, there was no significant difference in CAAs (1.6% vs 1.6%; risk difference, 0.013% [95% confidence interval, -0.34 to 0.37]; P = .953). The instrumental variable analyses showed similar results. CONCLUSIONS: The proportion of CAAs did not differ significantly between those receiving low- and high-concentration IVIG. To confirm the results of this study, prospective studies adjusting for duration of IVIG administration and duration of observation are needed.

Hypertrophic cardiomyopathy (HCM) is genetically heterogeneous. Different variants associated with HCM have been identified in several cardiac sarcomeric protein genes. We identified the heterozygous missense variant c.2191 C>A p. Pro 731 Thr in the MYH7 gene and the heterozygous frameshift variant c.1091-1092 insTGAA p.Lys364fs*in the MYH6 gene in a Japanese family. Family members with the double variants demonstrated severe phenotypes, such as sudden cardiac-related death and heart failure. These double variants were well segregated and might be responsible for the severity of cardiovascular events in affected family members. These double variants are potentially associated with specific phenotypes in HCM. Further studies are needed to analyze specific gene functions. <Learning objective: Hypertrophic cardiomyopathy (HCM) is genetically heterogeneous and is associated with different variants in sarcomeric protein genes. We identified a heterozygous missense variant in the MYH7 gene and a heterozygous frameshift variant in the MYH6 gene in a Japanese family. These double variants are potentially associated with specific phenotypes in HCM.>.