Biochemical measurements Flashcards
What is the best substance to measure GFR?
Inulin
What is the best endogenous substance to measure GFR?
Creatinine
What is clearance?
The volume of plasma that is theoretically cleared of a substance per minute
What is a better measurment than serum creatinine?
Creatinine clearance
What information do you need to calculate an estimated GFR?
Serum creatinine
Age
Sex
Ethnicity
Is eGFR more reliable at lower of higher GFR?
Lower. Becomes less accurate above 60
If it is essential to get an accurate assessment of GFR what test is done?
Inulin clearance
What test is used now to calculate eGFR?
4 variable MDRD
What protein levels in the urine suggest significant glomerular damage?
Above 150mg/day
What tests are useful in measuring proteinuria?
24 hour collection
Protein/creatinine ratio
What does microalbuminuria mean?
Excretion of abnormally high quantities of albumin but not high enough to sppear on a dipstick
What patients get routinely tested for microalbuminuria?
Diabetic patients
What biochemical sign is the earliest marker of diabetic nephropathy?
Microalbuminuria
A patients Urine:Serum osmolality is 1:1. What does this mean?
Intrinsic renal damage (tubules not working)
In the urinary sodium high or low in intrinsic renal damage?
High
