Day-to-day variation of the kidney proximal tubular injury markers urinary cystatin C, KIM1, and NGAL in patients with chronic kidney disease
- Resource Type
- Authors
- Bengt Fellström; Johanna Helmersson-Karlqvist; Anders Larsson; Inga Soveri
- Source
- Renal Failure, Vol 42, Iss 1, Pp 400-404 (2020)
Renal Failure
- Subject
- Male
Nephrology
030232 urology & nephrology
u-kim1
Urine
030204 cardiovascular system & hematology
Critical Care and Intensive Care Medicine
lcsh:RC870-923
chemistry.chemical_compound
0302 clinical medicine
Laboratory Study
Urologi och njurmedicin
Hepatitis A Virus Cellular Receptor 1
u-cystatin c
day-to-day variation
Aged, 80 and over
Kidney
biology
U-KIM1
Day-to-day variation
General Medicine
Middle Aged
Kidney Tubules
medicine.anatomical_structure
Creatinine
Female
medicine.medical_specialty
Coefficient of variation
Urinary system
U-cystatin C
Urology
03 medical and health sciences
Lipocalin-2
Internal medicine
medicine
Humans
Urology and Nephrology
Cystatin C
Renal Insufficiency, Chronic
Aged
Sweden
business.industry
U-NGAL
proximal tubular injury markers
medicine.disease
lcsh:Diseases of the genitourinary system. Urology
u-ngal
chemistry
biology.protein
business
Biomarkers
Kidney disease
- Language
- English
- ISSN
- 1525-6049
Background: It is important to know the intraindividual variation of biomarkers to be able to distinguish a change of a biomarker due to the course of the disease from the normal biological variation of the marker. The purpose of this study was to investigate the day-to-day variability of urine markers in nephrology patients. Materials: 23 nephrology patients were included in the study. First morning urine samples were collected daily for ten consecutive days and analyzed for U-cystatin C, U-KIM1, U-NGAL and U-creatinine. The day-to-day variation was calculated as concentrations of the markers and as creatinine ratios. Values deviating more than the 90th percentile of the normal intraindividual variation was used to define a disease/treatment specific change. Results: The day-to-day coefficient of variation (CV) for individual patients varied between 9.6 and 100.3% for NGAL (mean 45.6%) and between 8.8 and 107.3% for the NGAL/creatinine ratio (mean 43.8%). The corresponding values for KIM1 were between 10.9 and 60.2% (mean 30.1%) and for the ratio between 8.7 and 59.8% (mean 23.4%) and for cystatin C 3.8–67.4% (mean 25.0%) and for the cystatin C/creatinine ratio 5.9–78.4% (mean 24.8%). Conclusions: The similar intraindividual CV values between the renal tubules damage markers and their corresponding creatinine ratios speaks against using creatinine ratio. Using the 90th percentiles of the CV values as a limit for clinical change means that NGAL has to change by 83.3%, KIM1 by 45.5% and Cystatin C by 46.3% before the change can be considered clinically significant in patients with chronic kidney disease.