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Background The goal of this study was to investigate the prevalence and factors associated with persistent viral shedding (PVS) in hospitalized patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Methods This was a prospective observational study including all consecutive adults hospitalized with SARS-CoV-2 infection. When the first nasopharyngeal swab was positive for SARS-CoV-2 RNA (day 0), additional samples were obtained on days + 3, + 5, + 7 and then once every 7 days until virus detection was negative. PVS was defined as the duration of shedding of at least 21 days after diagnosis. The primary endpoint of this study was the prevalence of PVS. Results Data were obtained regarding 121 consecutive hospitalized patients with SARS-CoV-2 infection (median age 66 years, male sex 65.3%). Overall, the prevalence of PVS was 38% (46/121 patients). According to univariate analysis, factors associated with PVS were immunosuppression (6.7% vs 21.7%, p = 0.02), increased interleukin-6 (IL-6) levels (≥ 35 ng/ml) at the time of diagnosis (43.4% vs 67.3%, p = 0.02), time from onset of symptoms to diagnosis (median days 7.0 vs 3.5, p = 0.001), intensive care unit admission (22.7% vs 43.5%, p = 0.02), and need for invasive mechanical ventilation (20.0% vs 41.3%, p = 0.01). The multivariate analysis indicated that immunosuppression, increased IL-6 levels at the time of diagnosis, time from onset of symptoms to diagnosis, and need for mechanical ventilation were independent factors associated with PVS. Conclusions PVS was detected in up to 38% of hospitalized patients with SARS-CoV-2 infection and was strongly associated with immunosuppression, increased IL-6 levels, and the need for mechanical ventilation. Supplementary Information The online version contains supplementary material available at 10.1007/s40121-020-00381-8.

BACKGROUND Increases in cardiac troponin (cTn) in coronavirus disease 2019 (COVID-19) have been associated with worse prognosis. Nonetheless, data about the significance of cTn in elderly subjects with COVID-19 are lacking. METHODS From a registry of consecutive patients with COVID-19 admitted to a hub hospital in Italy from 25/02/2020 to 03/07/2020, we selected those ≥ 60 year-old and with cTnI measured within three days from the molecular diagnosis of SARS-CoV-2 infection. When available, a second cTnI value within 48 h was also extracted. The relationship between increased cTnI and all-cause in-hospital mortality was evaluated by a Cox regression model and restricted cubic spline functions with three knots. RESULTS Of 343 included patients (median age: 75.0 (68.0−83.0) years, 34.7% men), 88 (25.7%) had cTnI above the upper-reference limit (0.046 µg/L). Patients with increased cTnI had more comorbidities, greater impaired respiratory exchange and higher inflammatory markers on admission than those with normal cTnI. Furthermore, they died more (73.9%vs. 37.3%, P < 0.001) over 15 (6−25) days of hospitalization. The association of elevated cTnI with mortality was confirmed by the adjusted Cox regression model (HR = 1.61, 95%CI: 1.06−2.52, P = 0.039) and was linear until 0.3 µg/L, with a subsequent plateau. Of 191 (55.7%) patients with a second cTnI measurement, 49 (25.7%) had an increasing trend, which was not associated with mortality (univariate HR = 1.39, 95%CI: 0.87−2.22, P = 0.265). CONCLUSIONS In elderly COVID-19 patients, an initial increase in cTn is common and predicts a higher risk of death. Serial cTn testing may not confer additional prognostic information.

The SARS-CoV-2 infection causes severe respiratory involvement (COVID-19) in 5–20% of patients through initial immune derangement, followed by intense cytokine production and vascular leakage. Evidence of immune involvement point to the participation of T, B, and NK cells in the lack of control of virus replication leading to COVID-19. NK cells contribute to early phases of virus control and to the regulation of adaptive responses. The precise mechanism of NK cell dysregulation is poorly understood, with little information on tissue margination or turnover. We investigated these aspects by multiparameter flow cytometry in a cohort of 28 patients hospitalized with early COVID-19. Relevant decreases in CD56brightCD16+/- NK subsets were detected, with a shift of circulating NK cells toward more mature CD56dimCD16+KIR+NKG2A+ and “memory” KIR+CD57+CD85j+ cells with increased inhibitory NKG2A and KIR molecules. Impaired cytotoxicity and IFN-γ production were associated with conserved expression of natural cytotoxicity receptors and perforin. Moreover, intense NK cell activation with increased HLA-DR and CD69 expression was associated with the circulation of CD69+CD103+ CXCR6+ tissue-resident NK cells and of CD34+DNAM-1brightCXCR4+ inflammatory precursors to mature functional NK cells. Severe disease trajectories were directly associated with the proportion of CD34+DNAM-1brightCXCR4+ precursors and inversely associated with the proportion of NKG2D+ and of CD103+ NK cells. Intense NK cell activation and trafficking to and from tissues occurs early in COVID-19, and is associated with subsequent disease progression, providing an insight into the mechanism of clinical deterioration. Strategies to positively manipulate tissue-resident NK cell responses may provide advantages to future therapeutic and vaccine approaches., Author summary This is a detailed study of activating and inhibitory receptors in NK cells of COVID-19 patients when first admitted to the hospital for respiratory insufficiency. NK cells are known to be the first line of defense against invading viruses, and regulate downstream B and T cell responses, including antibody production. We observed intense NK cell activation with decreased functional activity, as well as intense circulation of putative tissue resident CD69+CD103+CXCR6+ NK cells, with a related surge in inflammatory CD34+ precursors from the bone marrow. The findings suggest that there is unprecedented trafficking of NK cells from peripheral tissues, their increased death with recruitment of emergency precursors from the bone marrow, and a relationship with the subsequent course of the disease of the patients. This in turn suggests possible areas of treatment and prevention.

Vitamin D deficiency is associated with increased risks of mortality in people with chronic kidney disease. The benefits and harm of vitamin D supplementation on cardiovascular outcomes and mortality are unknown. We aimed to assess the effectiveness of calcifediol in reducing mortality in patients with vitamin D insufficiency on hemodialysis compared to no additional therapy. A phase III, multicenter, randomized, open-label trial was conducted including 284 adults with vitamin D insufficiency undergoing hemodialysis who were randomly assigned to receive oral calcifediol or standard care for 24 months. Two hundred eighty-four participants were enrolled (143 assigned to the calcifediol group and 141 to the no additional therapy group). The primary outcome (mortality) occurred in 34 and 31 participants in the calcifediol and control group, respectively [hazard ratio (HR) 1.03; 95% confidence interval (CI) 0.63–1.67]. Calcifediol had no detectable effects on cardiovascular death (HR 1.06; 95% CI 0.41–2.74), non-cardiovascular death (HR 1.13; 95% CI 0.62–2.04), nonfatal myocardial infarction (HR 0.20; 95% CI 0.02–1.67) or nonfatal stroke (HR could not be estimated). The incidence of hypercalcemia and hyperphosphatemia was similar between groups. None of the participants underwent parathyroidectomy. In adults treated with hemodialysis and who had vitamin D insufficiency, calcifediol supplementation for 24 months had inconclusive effects on mortality and cardiovascular outcomes. NCT01457001

A striking abundance of cryptic and pseudocryptic species was highlighted in marine invertebrates by a number of studies, the majority of which focused however on cryptic diversity as such, without inferring on evolutionary drivers involved in organism diversification. The widespread polychaete Syllis gracilis Grube, 1840 was identified as a possible species complex by MALTAGLIATI et al. (2000), who identified Mediterranean marine and brackish populations as putative cryptic species on the basis of allozyme data. More recently, sequence data allowed to consider the allegedly cosmopolitan S. gracilis as a paraphyletic species complex, including at least three distinct Mediterranean lineages. To understand the role of biogeographical and ecological factors in the differentiation of the complex, populations of S. gracilis were sampled from eleven Mediterranean localities, and a combined morphological and molecular characterisation was carried out. Multivariate and univariate analyses on the morphological dataset highlighted that the majority of traits are fixed at population level, but it is possible to distinguish two morphotypes, one with short cirri, associated with intertidal coralline algae, and one with long cirri occurring on Sabellaria reefs and in brackish environments. On the other hand, 16S rDNA sequences highlighted the occurrence of three separated lineages, of which only two correspond to those identified by Álvarez-Campos et al. (2017). Therefore, S. gracilis includes at least four cryptic lineages. Molecular lineages did not show any correspondence with morphological diversity, and natural populations of S. gracilis usually included at least two cryptic lineages, without a clear distinction between marine and brackish-water populations. This outcome suggests that the relationship between the molecular pattern detected and ecological and biogeographical features is not straightforward. The observed morphological pattern is most likely due to local adaptations and phenotypic plasticity, while the separation between molecular lineages is possibly due to ancient geological events. The diversity and evolution of marine invertebrates is shaped by a number of different processes working and interacting at different spatial and temporal scales. The reconstruction of evolutionary processes should therefore take into consideration as many different evidence lines as possible. Although the inconsistent pattern detected make the integration of morphological and molecular patterns difficult, these patterns are the consequence of unpredictable interactions between different evolutionary drivers, thus representing an interesting case of irreducible evolutionary complexity in marine systems.