高橋 康平

BACKGROUND: Nationwide surveillance was conducted in Japan to clarify the status of pediatric invasive pneumococcal diseases (IPD) after introducing a 13-valent pneumococcal conjugate vaccine (PCV13). METHODS: Detailed clinical and epidemiologic information of IPD cases in children aged <15 years was collected from 10 of 47 prefectures in Japan from January 2014 to December 2022. Streptococcus pneumoniae strains isolated from sterile body sites were analyzed including capsular serotypes, multi-locus sequence typing (MLST), and antimicrobial susceptibility testing. The serotype-specific IPD incidence was calculated by imputing the serotypes for missing isolates to serotypes assumed based on the distribution of known serotypes. RESULTS: During the study period, 1033 IPD cases were reported. The incidence rate of total IPD in patients aged <5 years from 2014 to 2019 declined by 21.3 % compared with the rate from 2011 to 2013 before the introduction of PCV13. Compared with the incidence of total IPD from 2014 to 2019 and from 2020 to 2022, during the COVID-19 pandemic, the incidence of IPD among children aged <5 years declined by 49.7 %. In total, 932 IPD cases were identified as capsular serotypes. Among children aged <5 years, the most frequent serotype was 24F, followed by 15 A, 12F, 15C, 15B, and 10 A. Since 2014, after replacement with PCV13 in 2013, the rate of IPD by PCV13 minus PCV7 serotypes decreased, and non-PCV13 serotypes further increased. The serotype causing IPD in children aged <5 years, with PCV15-unique serotypes and PCV20-unique serotype were 8.6 % and 22.5 %, respectively. In terms of antimicrobial susceptibility, strains resistant to penicillin and cefotaxime decreased, whereas the meropenem non-susceptible strains increased in the post-PCV13 era. CONCLUSION: PCV13 introduction and the COVID-19 pandemic have had a significant impact on pediatric IPD in Japan. It is important to continuously monitor the epidemiological characteristics of pediatric IPD after the introduction of PCV20.

BACKGROUND: The ability to perform deep squats in children and adolescents is an essential component of lower extremity function. Especially for school-aged children and adolescents, the ability to perform deep squats is related to their daily life and school activities. Few reports have investigated the factors associated with deep squats ability in this population. This study aimed to identify the factors associated with deep squat ability in healthy Japanese children and adolescents. METHODS: A retrospective cohort study was conducted with children and adolescents aged 8-14 years in Japan from 2017 to 2019. Data on height, weight, ability to perform deep squats, general joint laxity, lower limb tightness, and the Hospital for Special Surgery Pediatric Functional Activity Brief Scale score were collected at the beginning of each year. Participants who were able to squat during their musculoskeletal screening were divided into two groups: those who could deep squat the following year and those who could not. Logistic regression analysis with variable selection was performed to calculate the odds ratio for each predicted risk factor associated with the inability to perform a deep squat. RESULTS: A total of 636 children and adolescents were included in the analysis, with 7.5 % of them being unable to perform deep squats the following year. The risk of being unable to deep squats significantly decreased with increasing age (odds ratio 0.66, 95 % confidence interval 0.50-0.87). In addition, higher weight (odds ratio 1.12, 95 % confidence interval 1.07-1.17) and higher Hospital for Special Surgery Pediatric Functional Activity Brief Scale score (odds ratio 1.05, 95 % confidence interval 1.01-1.10) were identified as risk factors associated with the inability to perform a deep squat. Other physical factors did not significantly contribute to the occurrence of deep squat abnormalities. CONCLUSIONS: Age, body weight, and physical activity levels were found to be associated with the ability to perform deep squats in healthy Japanese children and adolescents.

BACKGROUND: The usefulness of muscle ultrasonography for detection of fasciculations has been increasingly recognised, particularly in amyotrophic lateral sclerosis (ALS). This study aimed to elucidate distributions and characteristics of fasciculations in spinal and bulbar muscular atrophy (SBMA) and to compare the results of those in ALS. METHODS: In 24 SBMA and 16 ALS patients, muscle ultrasonography was systematically performed in the tongue, upper limb muscles (biceps brachii, triceps brachii, first dorsal interosseous (FDI), abductor pollicis brevis and abductor digiti minimi), trunk muscles (Th10 paraspinals and rectus abdominis) and lower limb muscles (vastus lateralis, biceps femoris, tibialis anterior and gastrocnemius). We assessed the presence of fasciculations and the fasciculation intensity (scored from 0 to 3) for each muscle. RESULTS: All SBMA and ALS patients showed fasciculations at least in two muscles. In SBMA patients, fasciculations were most frequently found in the tongue (100%), FDI (93%) and tibialis anterior (80%), whereas less frequently present in the proximal limb and trunk muscles, irrespective of age, disease duration and CAG repeat numbers. By contrast, in ALS patients, fasciculations were more diffusely distributed including the proximal limb and trunk muscles. When fasciculations were present, the intensity was higher in ALS patients, except for the tongue. CONCLUSIONS: Whereas both diseases exhibit extensive fasciculations, the distribution and intensity are different. SBMA is characterised by prominent involvement in the tongue and distal limb muscles, suggesting different pathophysiology of motor neuronal death in SBMA and ALS.

BACKGROUND: Air leakage during pulmonary resection is a major complication in thoracic surgery. It frequently occurs at sites of adhesion dissection, due to lung manipulation, and along the staple lines of automatic suturing devices, particularly in cases of pulmonary fragility such as those of emphysema and interstitial pneumonia. Persistent postoperative air leakage prolongs chest tube indwelling and extends hospitalization time. Staplers with absorbable tissue reinforcements have been introduced for pulmonary resection to prevent intraoperative stapler-related air leakage. This phase II prospective, open-label, randomized, parallel-group trial aims to validate the efficacy of staplers with or without absorbable tissue reinforcements in controlling stapler-related air leakage during anatomical pulmonary resections. METHODS: Overall, 120 patients will be randomized into two groups: one that will undergo conventional anatomical pulmonary resection and the other in which staplers with absorbable tissue reinforcements will be used. The primary endpoint will be intraoperative stapler-related air leakage. Data will be analyzed between 2024 and 2025. DISCUSSION: This trial will validate the effectiveness and safety of staple line reinforcements in controlling intraoperative air leakage during anatomical pulmonary resections, potentially leading to optimized strategies for patients with conditions such as emphysema and interstitial pneumonia. TRIAL REGISTRATION: This trial has been registered with the Japan Registry of Clinical Trials 1032220620 ( https://jrct.niph.go.jp/latest-detail/jRCTs031230224 ).

Criteria for airflow obstruction (AFO) at one year after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in pulmonary function tests (PFTs) are more stringent than the bronchiolitis obliterans syndrome (BOS) criteria of the National Institutes of Health. This single-center, retrospective cohort study evaluated the clinical impact of the AFO criteria at any time after transplantation. In 132 patients who underwent allo-HSCT from 2006 to 2016, the 2-year cumulative incidence of AFO was 35.0%, and the median time to diagnosis of AFO was 101 days after transplantation (range 35-716 days). Overall chronic graft-versus-host disease (cGVHD) incidence was significantly higher in patients with AFO than in those without AFO (80.4% vs. 47.7%, P < 0.01); notably, 37.0% of patients with AFO developed cGVHD after AFO diagnosis. AFO patients developed BOS with a 5-year cumulative incidence of 49.1% after AFO onset. The 5-year cumulative incidence of non-relapse mortality in the AFO group was higher than that in the non-AFO group (24.7% vs. 7.1%, P < 0.01). These results suggest that closely monitoring PFTs within two years after allo-HSCT, regardless of cGVHD status, is important for early detection of AFO and prevention of progression to BOS. (192words).