Clinical Chemistry Study Guide Questions With Complete Solutions

Causes of blood urea nitrogen (BUN) increase correct answer: - decreased Glomerular Filtration rate - increased urea production of liver - increased dietary protein and GI bleeding Causes of creatinine Increase correct answer: - less than 25% of original renal function - Muscle damage - decrease GFR Causes of Creatinine Decrease correct answer: - younger animals have a lower serum creatinine - Cachexia causes lower levels Causes of Serum phosphorus increase correct answer: - indicates 85% of nephrons are non-functional - immature animals because of bone growth Exogenous Renal clearance correct answer: - the estimation of GFR - determines creatinine clearance +)serum creatinine vs urine creatinine -performed when renal disease is suspected but BUN and Creatinine is WNL exogenous Creatinine Clearance correct answer: -creatinine is administered SQ or IV -urine is collected 3x in 20min intervals single injection methods for estimation of GFR correct answer: - post-iohexol clearance - inulin clearance Inulin Clearance correct answer: - considered the gold standard for measurement, but not widely available post-iohexol clearance correct answer: - inject iohexol IV, collect plasma plasma at 2,3 and 4 hours post -calculated using area under the plasma concentration vs time curve.