A negative correlation of CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A4 activity with PELD score (pediatric end-stage liver disease score, range from 0 to 38) used to estimate relative disease severity and survival of patients awaiting liver transplantation was reported by de Bock et al. [24]. This evidence concerns the gene CYP2D6 and End Stage Liver Disease.