IL6 and hydrops fetalis: Moreover, inflammatory biomarkers such as tumor necrosis factor alpha (TNF-α), interferon gamma (INF-γ), interleukin 1-β (IL-1 β) and interleukin 6 (IL-6) have been used to predict the prognosis of HF (Shirazi et al. 2017; Libby et al. 2018).