Objective: Covid-19 may cause thrombosis in both venous and arterial systems. Familiarity with the signs and symptoms of thrombosis and their treatment plays an important role in treating Covid-19 infection and its complications. D-Dimer and Mean platelet volume (MPV) are measurements related to the development of thrombosis. This study investigates whether MPV and D-Dimer values could be used to determine the risk of thrombosis and mortality in Covid-19 early stages. Methods: 424 patients were randomly and retrospectively included in the study, Covid 19 positive according to the World Health Organization (WHO) guidelines. Demographic and clinical characteristics such as age, gender, and length of hospitalization were obtained from the digital records of participants. Participants were divided into living and deceased groups. Results: WBC, neutrophils, and monocytes were significantly different in the two groups (p <0.001), and its values were lower in the living group than in the deceased group. MPV median values do not differ according to prognosis (p = 0.994). Creatinine, Procalcitonin, Ferritin, and the number of hospitalization days in living patients were significantly lower than in patients who died (p <0.001). Median values of D-dimer (mg / L) differ according to prognosis (p <0.001). While the median value was 0.63 in the survivors, it was found as 4.38 in the deceased. Conclusion: Our results did not show any significant relationship between the mortality of Covid-19 patients and their MPV levels. However, a significant association of D-Dimer and mortality in Covid-19 patients was observed. Keywords: COVID-19, MPV, D-Dimer, prognosis, mortality

Objective: To investigate the impacts of demographic, hematological, and biochemical factors on the clinical course and the prognostic outcome in adult COVID-19 patients. Methods: This retrospective study was performed in the internal medicine departments of 2 hospitals and data were extracted from the medical files of 1700 adult COVID-19 patients (836 females, 49.2%; 864 males, 50.8%) with an average age of 48.23 ± 16.68 (range: 18-93). Clinical data included baseline descriptives, prior medical history, admission date, treatment, and hematological and biochemical blood test results. The relationship between the survival, length of hospitalization, hematological, and biochemical parameters was investigated. Results: Advanced age (p<0.001), presence of at least 1 comorbid disease (p=0.045), increased length of hospitalization (p=0.006), elevated white blood cell (p=0.001) and neutrophil (p=0.002) counts, increased serum levels of glucose (p=0.027), blood urea nitrogen (p<0.001), AST (p=0.006), LDH (p<0.001), CRP (p>0.001), and D-dimer (p=0.001). In contrast, diminution of serum levels of albumin (p<0.001), ALT (p=0.028), calcium (p=0.022), and platelet count (p=0.010) were associated with increased mortality. There was a positive and weak relationship between serum D-dimer levels and length of hospitalization. Conclusion: Our data imply that identification and validation of indicators that predict COVID-19 disease progression to improve health outcomes are crucial. Age, comorbidities, immunological response, radiographic abnormalities, laboratory markers, and signs of organ dysfunction may all predict poor outcomes individually or collectively. It is critical to identify characteristics that predict COVID-19 problems to guide clinical management, improve patient outcomes, and allocation of limited resources. Keywords: SARS-Cov-2, COVID-19; severity; prognosis; outcome