CYP3A4 and cholangitis: Univariate logistic analysis revealed multiple factors significantly associated with the risks of switching IS drugs, including recipient CYP3A4 genotype, cholangitis before LT, GRWR, INR, serum albumin, graft volume reduction, the addition of MMF, donor age at LT, donor CYP3A4 genotype, acute rejection within 3 months after LT, portal vein complications, urinary complications, mental and neurological complications, and PTLD (Table 4).