Published papers

In this systematic review and meta-analysis, we sought to evaluate the prevalence of cardiac involvement in patients with COVID-19 using cardiac magnetic resonance imaging. A literature review was performed to investigate the left ventricular (LV) and right ventricular (RV) ejection fraction (EF), the prevalence of LV late gadolinium enhancement (LGE), pericardial enhancement, abnormality on T1 mapping, and T2 mapping/T2-weighted imaging (T2WI), and myocarditis (defined by modified Lake Louis criteria). Pooled mean differences (MD) between COVID-19 patients and controls for LVEF and RVEF were estimated using random-effects models. We included data from 10.462 patients with COVID-19, comprising 1.010 non-athletes and 9.452 athletes from 29 eligible studies. The meta-analysis showed a significant difference between COVID-19 patients and controls in terms of LVEF [MD = - 2.84, 95% confidence interval (CI) - 5.11 to - 0.56, p < 0.001] and RVEF (MD = - 2.69%, 95% CI - 4.41 to - 1.27, p < 0.001). However, in athletes, no significant difference was identified in LVEF (MD = - 0.74%, 95% CI - 2.41 to - 0.93, p = 0.39) or RVEF (MD = - 1.88%, 95% CI - 5.21 to 1.46, p = 0.27). In non-athletes, the prevalence of LV LGE abnormalities, pericardial enhancement, T1 mapping, T2 mapping/T2WI, myocarditis were 27.5% (95%CI 17.4-37.6%), 11.9% (95%CI 4.1-19.6%), 39.5% (95%CI 16.2-62.8%), 38.1% (95%CI 19.0-57.1%) and 17.6% (95%CI 6.3-28.9%), respectively. In athletes, these values were 10.8% (95%CI 2.3-19.4%), 35.4% (95%CI - 3.2 to 73.9%), 5.7% (95%CI - 2.9 to 14.2%), 1.9% (95%CI 1.1-2.7%), 0.9% (0.3-1.6%), respectively. Both LVEF and RVEF were significantly impaired in COVID-19 patients compared to controls, but not in athletes. In addition, the prevalence of myocardial involvement is not negligible in patients with COVID-19.

Primary malignant pericardial mesothelioma is an extremely rare disease. Malignant disease of the pericardium is an infrequent cause of cardiac tamponade. Hence, cardiac tamponade in the context of primary malignant mesothelioma of the pericardium is an uncommon clinical scenario. A 67-year-old male patient, an ex-smoker, complaining of progressive lethargy was referred to a hospital for investigation of persistent pericardial effusion. The pericardial fluid cytology was categorized as class Ⅲ. Thereafter, he was referred to our hospital for further evaluation. Fluorodeoxyglucose (FDG) positron emission tomography (PET) revealed FDG accumulation in the pericardium and mediastinal lymph node. Surgical biopsy of the pericardium was performed through a subxiphoid approach for a definitive diagnosis. Histopathological examination revealed diffuse infiltration of the pericardium by a malignant tumor consisting of epithelioid cells with large round nuclei and prominent nucleoli, arranged in a tubular papillary pattern. Finally, the patient was diagnosed with primary malignant pericardial mesothelioma of epithelioid type. The patient died 6 weeks after admission. This diagnosis must be considered in patients having unexplained massive pericardial effusion. Furthermore, we should consider prompt cytological analysis and FDG PET to arrive rapidly at a definitive diagnosis to administer combination chemotherapy that may provide clinical benefit. .

A 70-year-old male presented with a 1-month history of malaise and fever. He was diagnosed with chronic empyema and went into shock by cardiac tamponade after treatment. This case shows that even chronic empyema can cause cardiac tamponade. It should be considered as differential diagnoses of shock after empyema treatment.

Pseudomonas aeruginosa should be highly considered as a causative pathogen, when patients deteriorate rapidly despite community-acquired pathogen, and the radiological findings display a rapid emergence of cavitary lung lesions especially among patients at high risk of P aeruginosa pneumonia.

OBJECTIVES: Coronavirus disease (COVID-19) was severe in the Delta variant-dominated epidemic wave (fifth wave) in Japan. The clinical characteristics and effectiveness of COVID-19 vaccination are not fully understood in the Omicron variant-dominated wave (sixth and seventh waves), especially in hospitalized patients. We investigated the relationship between vaccination and disease severity in the Omicron-dominated wave and compared these variant-dominated waves. METHODS: The nationwide COVID-19 database (Japan COVID-19 Task Force) was used to compare clinical characteristics and critical outcome in patients hospitalized from Delta (5th, N=735) vs Omicron-dominated waves (6th, N=495; 7th, N=128). RESULTS: Patients in the sixth and seventh waves had a lower incidence of critical outcomes and respiratory outcomes, and a higher incidence of bacterial infection, although the mortality rate did not differ significantly between waves. In the sixth and seventh waves, 138 (27.9%) and 29 (22.7%) COVID-19 patients were unvaccinated, respectively. Multivariable analysis adjusted with previously reported factors revealed that the proportion of 1) critical outcomes and 2) respiratory outcomes decreased in a frequency-dependent manner; 1) (the number of vaccinations): 1-2 times, aOR 0.37 (95% CI; 0.20-0.69); 3-4 times: aOR 0.25 (95% CI; 0.11-0.58), 2) 1-2 times, aOR 0.43 (95% CI; 0.27-0.66); 3-4 times: aOR 0.36 (95% CI; 0.21-0.60). CONCLUSIONS: COVID-19 hospitalized patients with Omicron infections showed a lower incidence of critical outcomes than those with Delta infections, and COVID-19 vaccination may contribute to preventing respiratory failure.

Macrolides are used to treat various inflammatory diseases owing to their immunomodulatory properties; however, little is known about their precise mechanism of action. In this study, we investigated the functional significance of the expansion of myeloid-derived suppressor cell (MDSC)-like CD11b+Gr-1+ cells in response to the macrolide antibiotic clarithromycin (CAM) in mouse models of shock and post-influenza pneumococcal pneumonia as well as in humans. Intraperitoneal administration of CAM markedly expanded splenic and lung CD11b+Gr-1+ cell populations in naïve mice. Notably, CAM pretreatment enhanced survival in a mouse model of lipopolysaccharide (LPS)-induced shock. In addition, adoptive transfer of CAM-treated CD11b+Gr-1+ cells protected mice against LPS-induced lethality via increased IL-10 expression. CAM also improved survival in post-influenza, CAM-resistant pneumococcal pneumonia, with improved lung pathology as well as decreased interferon (IFN)-γ and increased IL-10 levels. Adoptive transfer of CAM-treated CD11b+Gr-1+ cells protected mice from post-influenza pneumococcal pneumonia. Further analysis revealed that the CAM-induced CD11b+Gr-1+ cell expansion was dependent on STAT3-mediated Bv8 production and may be facilitated by the presence of gut commensal microbiota. Lastly, an analysis of peripheral blood obtained from healthy volunteers following oral CAM administration showed a trend toward the expansion of human MDSC-like cells (Lineage-HLA-DR-CD11b+CD33+) with increased arginase 1 mRNA expression. Thus, CAM promoted the expansion of a unique population of immunosuppressive CD11b+Gr-1+ cells essential for the immunomodulatory properties of macrolides.

BACKGROUND: Late-onset noninfectious pulmonary complications (LONIPCs), which occur more than 3 months after allogeneic hematopoietic stem cell transplantation (HSCT), are major causes of morbidity and mortality after transplantation. Among LONIPCs, we occasionally treat patients with late-onset severe restrictive lung defect after HSCT; however, its clinical features have not been fully elucidated. METHODS: A retrospective chart review of a single center on cases of late-onset severe restrictive lung defect after HSCT was performed. Among 453 patients who survived longer than 100 days after allogeneic HSCT with evaluable spirometry data, 12 patients (2.6%) developed late-onset severe restrictive lung defect (i.e., vital capacity percent of predicted less than 60%). RESULTS: Median duration from transplantation to diagnosis of late-onset severe restrictive lung defect cases was 44.5 months. Major computed tomography (CT) finding was pleuroparenchymal thickening with volume loss, an evidence of fibrosis, predominantly in upper lobes (n = 7), which was consistent with pleuroparenchymal fibroelastosis. The remaining patients showed unclassifiable interstitial pneumonia pattern (n = 2) and airway-predominant pattern (n = 3). The diffusing capacity for carbon oxide tended to decrease, while the residual volume/total lung capacity ratio tended to increase after HSCT. Of 12 patients, 8 patients died and the median month from diagnosis to death was 33.5 months. Seven patients died of pulmonary or systemic infection, and one patient died due to relapse of the primary disease. CONCLUSION: Severe restrictive lung defect could develop in selected cases in the late-phase after HSCT and could be a unique clinical entity with specific radiographical findings.

BACKGROUND AND DESIGN: The coronavirus disease (COVID-19) pandemic is having a devastating effect worldwide. Host genome differences between populations may influence the severity of COVID-19. The Japan COVID-19 Task Force is conducting host genome analysis of hospitalized patients with COVID-19 from more than 70 institutions nationwide in Japan. This report describes the clinical characteristics of patients enrolled to date. RESULTS: The median (interquartile range) age of the 1674 patients included in the analysis was 59 (45-71) years, and more than half of the patients (66.2%) were male. Less than half of the patients (41.2%) had severe disease. The case fatality rate was 3.2%. CONCLUSIONS: Since this is a hospital-based study, the number of severe cases was relatively high, but the case fatality rate was relatively low, when compared to that of other countries. In the future, we will continue to enroll patients and conduct genome analyses of patients with COVID-19.