The non-SI ratio (BCR) is BUN (mg/dL) / plasma creatinine (mg/dL). The reference range is around 8-15 [5] and the most commonly used cut-off value to define increased BCR is 20. The SI ratio (UCR) is plasma urea (mmol/L) / (plasma creatinine (μmol/L) divided by 1000). The factor of 1000 is needed to convert the creatinine result from μmol/L Creatinine is a nonprotein nitrogenous substance derived from muscle creatine. •. Circulating levels vary with dietary intake of creatine and muscle mass. •. It distributes through all body water more slowly than urea. •. It is freely filtered through the glomeruli, not reabsorbed in the tubules, and excreted in urine. Urea is a nitrogen-containing chemical product which is produced on a scale of some 100,000,000 tons per year worldwide. Urea is commercially produced from synthetic ammonia and carbon dioxide. Urea can be produced as prills, granules, flakes, pellets, crystals and solutions. Warning: Physicians and Healthcare Professionals are responsible to employ good clinical judgement in selecting and interpreting Clinical data (inputs, outputs), and to verify all processing (data/knowledge) obtained through the use of Synt®, MediCalc®, iDox®, eH&P™, or any of ScyMed's systems and/or applications. Results. BUN residuals were not related to eGFR but to daily protein intake (DPI), while BUN was related to both eGFR and DPI. BUN was inversely associated with hemoglobin level (β -0.03; 95% confidence interval [CI] -0.04, -0.03; P <0.001) in the multivariable linear regression analysis adjusted for multiple confounders including eGFR, and BUN residual used instead of BUN was also inversely The blood urea nitrogen (BUN) test measures the amount of urea nitrogen in the blood. Urea nitrogen only reflects the nitrogen component of urea and not the whole urea molecule. In healthy individuals, normal BUN levels range between 5 to 20 mg/dL or 1.8 to 7.1 mmol/L; however, reference ranges may vary between laboratories due to changes in .

convert urea to bun