However, paradoxically, the serum levels of inflammatory markers (interleukin-4, interleukin-6 and tumor necrosis factor-alpha) were highest in non-HD patients with COVID-19 infection, followed by non-HD patients without COVID-19, and the lowest levels of inflammatory markers were observed in ESRD-HD patients irrespective of COVID-19 infection. This evidence concerns the gene IL4 and COVID-19.