Coronavirus disease 2019 (COVID-19) is a recently described infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since late 2019, COVID-19 has rapidly spread in virtually all countries, imposing the adoption of significant lockdown and social distancing measures. The activation of the coagulation cascade is a common feature of disseminated intravascular coagulation and adverse clinical outcomes in COVID-19 patients. In this study, we conducted a meta-analysis aiming to investigate differences in serum D-dimer concentrations in patients with and without severe COVID-19 disease. An electronic search in Medline (PubMed), Scopus and Web of Science was performed with no language restrictions, and 13 articles were reporting on 1,807 patients (585, 32.4% with severe disease) were finally identified and included in the meta-analysis. The pooled results of all studies revealed that the D-dimer concentrations were significantly higher in patients with more severe COVID-19 (SMD: 0.91 mg/L; 95% CI, 0.75 to 1.07 mg/L, p < 0.0001). The heterogeneity was moderate (I 2 = 46.5%; p = 0.033). Sensitivity analysis showed that the effect size was not modified when any single study was in turn removed (effect size range, 0.87 mg/L to 0.93 mg/L). The Begg's (p = 0.76) and Egger's tests (p = 0.38) showed no publication bias. In conclusion, our systematic review and meta-analysis showed that serum D-dimer concentrations in patients with severe COVID-19 are significantly higher when compared to those with non-severe forms.

: Carotid artery disease is commonly encountered in clinical practice and accounts for approximately 30% of ischemic strokes in the general population. Numerous biomarkers have been investigated as predictors of the onset and progression of carotid disease, the occurrence of cerebrovascular complications, and overall prognosis. Among them, blood cell count (BCC) indexes of systemic inflammation might be particularly useful, from a pathophysiological and clinical point of view, given the inflammatory nature of the atherosclerotic process. The aim of this review is to discuss the available evidence regarding the role of common BCC indexes, such as the neutrophil to lymphocyte ratio (NLR), monocyte to lymphocyte ratio (MLR), platelet to lymphocyte ratio (PLR), mean platelet volume (MPV), platelet distribution width (PDW), and red cell distribution width (RDW), in the diagnosis and risk stratification of carotid artery disease, and their potential clinical applications.

Lower limb amputations due to ischemia represent an important health care and social issue. However, there are currently no specific biomarkers able to predict the risk of amputation and postamputation complications and prognosis. We conducted a systematic review of studies investigating whether blood cell count indexes of systemic inflammation are linked to the risk and the outcome of lower limb amputations due to ischemia. Overall, in 22 studies involving 8832 patients selected for review, several blood cell count indexes, particularly the neutrophil lymphocyte ratio, showed some promise in terms of predicting amputations and general outcomes of conservative and surgical treatments, as well as postamputation complications and prognosis. However, largely due to methodological limitations, further prospective studies are required to establish the clinical utility and applicability of blood cell indexes in the routine management of patients with ischemia-related lower limb amputations.