Sars-Cov-2 infection and diabetic patient
In light of currently available data, people with diabetes appear to be more susceptible to Sars-CoV-2 infection. Predisposing risk factors are mainly secondary diseases caused by diabetes, such as coagulation dysfunction, inflammatory tissue status, nephropathy, cardiovascular diseases, immunodepressed status. An extensive epidemiological study of 72,314 patients with COVID-19 in China indicated that patients with diabetes have a mortality rate three times higher than all patients with COVID-19 (8). Diabetes is known to cause homeostasis dysfunction of the coagulation system and fibrinolytic cascade and hyperactive inflammation. These two components also manifest themselves in the more severe stages of Sars-Cov-2 infection. In the most severe stages of infection, the major complications are caused by a generalized hyperactive inflammatory state and coagulative dysfunction with risk of thrombosis and lung injury. In a study conducted on 174 patients with COVID-19 in Wuhan, China, people with diabetes had a higher concentration of inflammatory markers and a higher incidence of coagulopathy associated with higher mortality than those without diabetes (9). Another key aspect to highlight is that during the Sars-Cov epidemic it was noted that patients with viral infection had higher blood sugar levels than patients with infections caused by other viral agents. (10) Today it is known that Sars-Cov and Sars-Cov-2 use ACE-2 membrane glycoprotein to penetrate cells. In vitro and animal studies have shown that Sars-Cov binds ACE-2 also on pancreatic islands, damaging their function and causing a lack of adequate insulin production, (11) this biological mechanism is probably the cause of the hypeglycemia noticed in patients with Sars-Cov. Considering that sars-cov and Sars-Cov-2 share a high percentage of genomic similarity, and that Sars-Cov-2 also binds ACE-2, a risk of hyperglycemia could be hypothesized also in patients with COVID-19, as happened in the Sars-Cov epidemic. At the moment there are no data from epidemiological studies in this respect.