Results
IMC revealed by clustering analyses a more prominent, phenotypically shifted cytotoxic CD8+ T cell population and highly activated monocyte/macrophage (Mo/Mac) clusters in COVID-MDR. The RNA sequencing transcriptome demonstrated a more robust cytotoxic response in COVID-MDR skin. However, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was not detected in skin biopsies at the time point of MDR diagnosis. Serum proteomic profiling of COVID-MDR patients revealed up-regulation of various inflammatory mediators (IL-4, IL-5, IL-6, IL-8, IL-18, TNF, and IFN-γ), eosinophil and Mo/Mac -attracting chemokines (MCP-2, MCP-3, MCP-4 and CCL11). Analyses of cytokine networks demonstrated a relatively milder cytokine storm in DRESS compared to COVID-MDR, while MDR did not exhibit such features.