Concerning diseases associated with PH, Selvaraj et al. [30] demonstrated that Log cystatin C was directly correlated with echocardiogram-derived PASP in patients with chronic kidney disease; Secemsky et al. [31] analyzed 332 HIV-infected patients and found that elevated cystatin C was associated with the development of PH; for patients with systemic lupus erythematosus, cystatin C differentiated those with severe cardiovascular prognosis [32]; and in HF patients, cystatin C independently predicted outcome [33]. The gene discussed is CST3; the disease is hydrops fetalis.