RT Book, Section A1 Kasper, Dennis L. A1 Fauci, Anthony S. A1 Hauser, Stephen L. A1 Longo, Dan L. A1 Jameson, J. Larry A1 Loscalzo, Joseph SR Print(0) ID 1128782723 T1 Azotemia and Urinary Abnormalities T2 Harrison's Manual of Medicine, 19e YR 2016 FD 2016 PB McGraw-Hill Education PP New York, NY SN 9780071828529 LK accessmedicine.mhmedical.com/content.aspx?aid=1128782723 RD 2024/04/25 AB Azotemia is the retention of nitrogenous waste products excreted by the kidney. Increased levels of blood urea nitrogen (BUN) (>10.7 mmol/L [>30 mg/dL]) and creatinine (>133 μmol/L [>1.5 mg/dL]) are ordinarily indicative of impaired renal function. Renal function can be estimated by determining the clearance of creatinine (CLcr) (normal >100 mL/min); this can be directly measured from a 24-h urine collection using the following equation: