The investigating group aims at performing an observational, prospective study that involves the evaluation of circulating biomarkers predictive of clinical evolution in patients suffering from COVID-19 disease.

In particular, the aim will be to verify whether there are transcripts or cytokines / chemokines in peripheral blood, modulated differently in patients with COVID-19, distinguished on the basis of the evolution towards more severe clinical pictures that require patient intubation or that show signs of cardiovascular damage.

The study will be based on the transcriptional analysis of the entire genome and serum protein to evaluate the expression of a broad spectrum of cytokines and chemokines. Genome analysis will allow the genotype to be correlated to the identified gene expression profiles.

Study design This observational, prospective, monocentric study will make use of the recruitment of consecutive patients with COVID-19. Enrollment will last 6 months or, considering the desirable drop in infections in the next few weeks, until exhaustion of enrolled patients. Enrollment will be followed by 18 months dedicated to transcriptomics and seroproteomics investigations, for a total duration of the study of 24 months.

All patients will receive optimal medical therapy, and will undergo laboratory or instrumental examinations (chest x-ray, CT, echocardiography) as needed.

Blood samples will be taken at the entrance and then twice a week for the duration of the hospitalization (generally 2-3 weeks).

Anamnesis will be noted for all patients. In addition, at all times, patients will undergo clinical evaluation and the following laboratory tests, which include:

• blood count
• biochemistry
• standard coagulation and thrombin generation, fibrin generation and fibrinolysis (INR, PTT, D-dimer, Tissue Plasminogen Activator TPA, Plasminogen Activator Inhibitor PAI-2, Plasmin-AntiPlasmin complex PAP, Thrombin activated Fibrinolysis Inhibitor TAFI, Thrombin-AntiThrombin complex TAT, Prothrombin Fragment PF 1+2, Fibrinopeptide A)
• inflammation/infection (IL-6, procalcitonin, ferritin, PCR, sCD14, TLR3 and 4, RANTES, CCR3 and 4
• other (troponin I, NT-pro-BNP, Hb1Ac). A subgroup of patients will undergo a microcirculation analysis with SDF (Sidestream Dark Field imaging).

Inclusion Criteria:

1. Age 18 years or older
2. Positivity to the test for SARS-Cov-2
3. Informed consent to enrollment in the study.
4. For Intensive Care patients: entry into the intensive unit and / or endotracheal intubation for no more than 4 days.
5. For patients in the COVID19 wards: home hospitalization or emergency room for no more than 4 days.

Exclusion Criteria:

1. Age less than 18 years
2. Pregnant women
3. Patients with malignant neoplasm, autoimmune diseases.
4. Hospitalization as transfer from another hospital or other similar facility.

240 patients with COVID-19 will be recruited, including up to 60 patients from the intensive care and 180 from the specialized COVID19 departments of the IRCCS Policlinico San Donato. The sample size is estimated based on the average length of hospitalization of the patients and the maximum capacity of the clinical and laboratory units involved in the study.