1203 STING/type i interferon pathway activation in patients with perniosis during the COVID–19 pandemic

Abstract

1203 Figure 1Clinical appearance of perniosis in study patients showing red and purple papules over several toes some with near blisters (A and B). MxA staining of skin from perniosis lesion (D) showing lymphocytic inflammation in the dermis with perivascular and periadenexal inflammation. There is prominent MxA staining in the epidermis, dermal inflammatory infiltrate and in the superficial endothelial cells indicating interferon activation in skin. This is compared to no MxA staining in normal skin (C).[Figure omitted. See PDF]ConclusionsThe frequency of perniosis during the COVID pandemic, suggests a relationship between these two conditions although direct evidence of COVID-19 infection has been limited. We observed a trend toward higher IFN-b gene expression in PBMC as well as higher phospho-STING protein expression in CD14 monocytes and, most significantly, strong expression of MxA in skin. While the small number of patients preclude a definitive explanation, our data suggest that COVID associated perniosis is an interferonopathy. We propose that acute, transient COVID infection led to monocyte activation, IFN-I production and damage to the small vessels, likely aggravated by cold exposure.