Alterações hematológicas associadas à COVID-19 em pacientes sintomáticos

Abstract

In late December 2019, the world faced a new public health emergency with the emergence in Wuhan, China, of the first cases of pneumonia, of a previously unknown origin. The associated pathogen, a new coronavirus, is now widely known as SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2), belongs to the genus Beta-coronavirus, and is a viral particle structurally composed of organized glycoproteins, such as protein peak Spike (S), which gives the virus the “crown” aspect, the HE protein (Hemagglutinin-Esterase), the membrane protein (M), and the envelope protein (E). Inside the virus, there is the presence of a nucleoprotein (N), which is associated with single-stranded RNA in a helical structure. SARS-CoV-2 has a 79% similarity to another virus in the same family, SARS-CoV, and like this one, it uses the human angiotensin-converting enzyme 2 (ECA-2) as a receptor to invade the host cells and cause disease. Considering the variety of signs and symptoms that are associated with SARS-CoV-2 infection and the scale of this public health emergency, the analysis of hematological parameters that change in COVID-19 can help in determining the prognosis and faster treatment of symptomatic cases of this disease. Based on the studies analyzed, it was observed that the majority of symptomatic cases of COVID-19 had significant lymphopenia, which was related to the worsening of the patients' prognosis, since lymphocytes are essential cells in the defense of viral infections. In addition, another important finding was thrombocytopenia, which was also related to the severity of cases in this disease, as low levels of platelets can generate disseminated intravascular coagulation, leading the individual to death more quickly. Other changes have been described as COVID-19 severity markers, such as an increase in the concentration of D-dimer, which indicates the occurrence of thrombotic events.