Furthermore, Wang et al. demonstrated that both focal and diffuse fibrosis were associated with GDF-15 levels in HF patients.57 Given the pleiotropic nature and broad involvement in diverse pathophysiological pathways – including inflammation, metabolic stress, and tissue injury – we do not consider GDF-15 to represent a unique or organ-specific signalling axis between the heart and kidney. The gene discussed is GDF15; the disease is hydrops fetalis.