Sera of patients with acute SCLS showed elevation of seven cytokines, CXCL10 (C-X-C motif chemokine ligand 10), angiopoietin-2 chemokine ligand 2 (CCL2), interleukin-12, interleukin-1 beta, interleukin-6, interleukin-8, and tumor necrosis factor-alpha. This evidence concerns the gene IL6 and capillary leak syndrome.