IL6 and hydrops fetalis: Since 1990, levels of several inflammatory mediators, including tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), IL-1β, IL-18, and immunological antigens, were validated to be increased in the plasma of HF patients (Torre-Amione et al., 1996; Anker and von Haehling, 2004; Braunwald, 2008).