CST3 and acute kidney injury: However, preterm-born children with neonatal AKI, unlike both preterm peers without AKI and term-born controls, demonstrated lower cystatin C-based eGFR, higher nocturnal SBP, and increased blood pressure load in ABPM, elevated urinary KIM-1/creatinine and NGAL/creatinine levels, and higher serum TFF3.