CreatinineAlbuminuriaGlomerular Filtration RateBiological MarkersUrineKidneyKidney Function TestsKidney DiseasesUrinalysisAcute Kidney InjuryProteinuriaCystatin CRenal InsufficiencyKidney Failure, ChronicBlood Urea NitrogenUreaKidney TransplantationTime FactorsUrine Specimen CollectionCreatineCystatinsMetabolic Clearance RateProspective StudiesChromatography, High Pressure Liquid