The influence of pre-admission antiplatelet and anticoagulation therapy on the illness severity in hospitalized patients with COVID-19 in Japan.

INTRODUCTION: Many articles have reported that the coronavirus disease 2019 (COVID-19) causes coagulation abnormalities and pulmonary thrombosis, contributing to a poorer prognosis. The study aimed to evaluate whether pre-admission anticoagulation and antiplatelet therapy prevented severe COVID-19 illness or not. MATERIALS AND METHODS: We conducted a study to determine whether taking antiplatelet or anticoagulation agents before admission affected the severity on admission using a large nationwide cohort of hospitalized COVID-19 patients in Japan. We analyzed a large nationwide cohort of hospitalized COVID-19 patients in Japan from February 9 to July 31, 2020. RESULTS AND CONCLUSION: A total of 4265 patients from 342 facilities in Japan were included. Their use was associated with a slight reduction in the disease severity on admission in a propensity score-matched analysis which controlled for underlying diseases. However, this difference was not statistically significant.

Myeloid cell dynamics correlating with clinical outcomes of severe COVID-19 in Japan.

An expanded myeloid cell compartment is a hallmark of severe coronavirus disease 2019 (COVID-19). However, data regarding myeloid cell expansion have been collected in Europe, where the mortality rate by COVID-19 is greater than those in other regions including Japan. Thus, characteristics of COVID-19-induced myeloid cell subsets remain largely unknown in the regions with low mortality rates. Here, we analyzed cellular dynamics of myeloid-derived suppressor cell (MDSC) subsets and examined whether any of them correlate with disease severity and prognosis, using blood samples from Japanese COVID-19 patients. We observed that polymorphonuclear (PMN)-MDSCs, but not other MDSC subsets, transiently expanded in severe cases but not in mild or moderate cases. Contrary to previous studies in Europe, this subset selectively expanded in survivors of severe cases and subsided before discharge, but such transient expansion was not observed in non-survivors in Japanese cohort. Analysis of plasma cytokine/chemokine levels revealed positive correlation of PMN-MDSC frequencies with IL-8 levels, indicating the involvement of IL-8 on recruitment of PMN-MDSCs to peripheral blood following the onset of severe COVID-19. Our data indicate that transient expansion of the PMN-MDSC subset results in improved clinical outcome. Thus, this myeloid cell subset may be a predictor of prognosis in cases of severe COVID-19 in Japan.

Novel SARS-CoV-2 Variant in Travelers from Brazil to Japan.

Multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with higher transmission potential have been emerging globally, including SARS-CoV-2 variants from the United Kingdom and South Africa. We report 4 travelers from Brazil to Japan in January 2021 infected with a novel SARS-CoV-2 variant with an additional set of mutations.

Association of plain computed tomography-determined pulmonary artery-to-aorta ratio with clinical severity of coronavirus disease 2019.

Coronavirus disease (COVID-19) is associated with pulmonary hypertension due to pulmonary embolism, which affects subsequent outcomes. However, definitive diagnosis of pulmonary hypertension is difficult because of the risk of spreading the infection. Here, we assess the utility of plane computed tomography in noninvasively predicting the clinical severity of COVID-19.

A new challenge of unfractionated heparin anticoagulation treatment for moderate to severe COVID-19 in Japan.

Hypercoagulation and anticoagulation treatment have become new challenges in coronavirus disease 2019 (COVID-19) patients during the COVID-19 pandemic. We herein suggest an algorithm for an anticoagulation treatment with unfractionated heparin in moderate to severe COVID-19 cases in Japan, and report a case of COVID-19 pneumonia with anticoagulation treatment. Although several promising drugs for COVID-19 are being tested in clinical trials, definitive treatments have not yet been established. In this report, we demaonstrate that anticoagulation treatment with unfractionated heparin has the possibility of becoming at least a supportive treatment for COVID-19 patients.

[A case of probable catastrophic antiphospholipid syndrome with multi-organ failure presenting as a transient increase of antiphospholipid antibody levels].

A 44-year-old woman was admitted to our hospital with shock, massive pneumonia and respiratory failure, liver and renal dysfunction, and cerebral infarction. Based on these symptoms, we suspected the presence of disseminated intravascular coagulation and multiple organ dysfunctions due to massive pneumonia or catastrophic antiphospholipid syndrome (CAPS). Therefore, the patient was placed on a respirator and was administered ciprofloxacin, doripenem hydrate, thrombomodulin, antithrombin III, and methylprednisolone pulse therapy. Because the patient's antiphospholipid antibody titer was low on the day of admission (day 1), we did not include CAPS in the differential diagnosis and discontinued prednisolone treatment on day 6. However, the anticardiolipin immunoglobulin M antibody titer was found to be elevated on day 7; in addition, a transient increase in the anticardiolipin anti-ß2 glycoprotein antibody titer was noted on re-examination. Moreover, on day 8, the thrombopenia and alveolar hemorrhage suddenly exacerbated. We finally diagnosed the patient with CAPS, and therefore resumed methylprednisolone therapy. Subsequently, the inflammation, respiratory failure, and thrombopenia rapidly improved, and the patient was extubated on day 12.