Chronic kidney disease (CKD) is a major non-communicable disease and a leading cause of mortality worldwide. With the increasing prevalence of risk factors such as diabetes mellitus, obesity, and hypertension in the 21st century, CKD currently affects over 10% of the global population. The clinical and economic burden of this widespread disease is projected to continue to rise worldwide. Early detection, treatment, and monitoring of this progressive condition through accurate clinical laboratory testing of CKD biomarkers are paramount to mitigate this growing healthcare challenge. The development of reference materials (RMs) and reference measurement procedures (RMPs) for these clinical analytes is pivotal to ensuring accurate measurements using in vitro diagnostics. In this review, we emphasize the importance of establishing RMs and RMPs to standardize the measurements of key clinical markers for CKD, i.e., urine and serum creatinine, urine albumin, serum cystatin C, and urea. Standardizing CKD biomarker measurements based on RMs and RMPs can help support global efforts to reduce CKD-related morbidity and healthcare costs by ensuring reliable diagnostic practices.

Acute kidney injury (AKI) and chronic kidney disease (CKD) are major health problems. Urinary biomarkers have both diagnostic and prognostic utility in AKI and CKD. However, how biomarker excretion rates should be reported, especially whether they should be normalised to urinary creatinine concentration (uCr), is controversial. Some studies suggest that normalisation to uCr may be inappropriate at times, as urinary creatinine excretion rate may vary greatly, depending on the situation. Notably, recent studies suggest that while normalisation of values to UCr may be valid for the evaluation of CKD and prediction of AKI sequelae and occurrences, it could be inappropriate for the diagnosis of AKI, or in the presence of certain acute kidney disease states.
Acute Kidney Injury ; urine ; Biomarkers ; urine ; Creatinine ; urine ; Glomerular Filtration Rate ; Humans ; Kidney ; physiopathology ; Nephrology ; methods ; standards ; Renal Insufficiency, Chronic ; urine ; Treatment Outcome ; Urinalysis ; standards