This significant association of CKD with severe COVID-19 infection was observed also in the meta-analysis by Lippi [21]. This can be explained by the pro-inflammatory state and by the alterations of the innate and adaptive immune response associated with CKD. This immune profile increases susceptibility to all infections [104]. These findings suggest that COVID-19 patients with high baseline serum levels of creatinine are more likely to be led to intensive care unit treatment and to undergo mechanical ventilation, because the presence of a renal disease on admission constitutes a higher risk of negative prognosis. It has been recently shown that a large part of COVID-19 patients suffer from other comorbidities and most of these patients are also elderly and males [102,103]. Among these comorbidities, the presence of chronic kidney disease is an independent risk factor of poor prognosis. It is also true, on the contrary, that nephropathic patients are mainly affected by hypertension and cardiovascular disease per se and this can lead to a higher risk of COVID-19 infection when compared with the general population or with patients without kidney disease [105]. Nephropathic patients are also patients with cardiovascular disease which is currently considered a biomarker of increased risk for COVID 19 infection and for poor prognosis [105]. However, an increased risk of death, about 3–8 times, was found in patients infected with other viruses such as H1N1 flu virus and who developed kidney injury during infection as compared to those who had not [106]. Moreover, patients who enter the hospital with elevated serum creatinine levels were predominantly male and older (median age was 73 years) and were more severely ill compared with patients who had normal serum creatinine (median age was 61 years). In addition, patients with increased baseline serum creatinine levels show an alteration of leukocyte count with an increase in the absolute number of leukocytes and a decrease in lymphocyte and platelet counts. Coagulation pathway abnormalities, which include prolonged activated partial thromboplastin time and higher D-dimer, are more frequent in patients with increased baseline serum levels of creatinine. The rate of patients with increased procalcitonin, and the plasma levels of aspartate aminotransferase and LDH are also higher in patients with CKD compared with those with normal renal function. The incidence of in-hospital death in patients with CKD was found to be significantly higher than in those patients with normal baseline serum levels of creatinine.