Biochemistry

Question 1

List criteria that the ideal marker of GFR would fulfil

Answer 1

Appear at constant rate
Freely filtered at glomerulus
Not reabsorbed or secreted

Question 2

Which substance fulfils all the criteria for being an accurate measure of GFR, but is not usually used due to impracticality?

Answer 2

Inulin

Question 3

What is the most widely used marker for GFR?

Answer 3

Creatinine

Question 4

Which 1 of the criteria for being an accurate measure of GFR does creatinine not satisfy?

Answer 4

It is secreted into the renal tubule, but this is a small amount

Question 5

Creatinine is very sensitive to small reductions in GFR. True/False?

Answer 5

False
Only sensitive (rises) when large reduction in GFR occurs

Question 6

Give the equation for urinary creatinine clearance

Answer 6

[creatinine]urine x urine volume
/
[creatinine]serum x duration of collection

Question 7

Which formula is now more regularly used to determine GFR?

Answer 7

MDRD eGFR formula

170 x [creatinine]serum^-0.99 x [age]^0.176 x [0.762 if female] x [1.180 if black]

Question 8

Which disease is characteristically associated with overflow proteinuria?

Answer 8

Multiple myeloma

Question 9

What happens in glomerular proteinuria?

Answer 9

Dysfunctional glomerulus allows protein to leak through, producing albuminuria and nephrotic syndrome

Question 10

Microalbuminuria refers to a small amount of albumin in the urine. True/False?

Answer 10

FALSE

Refers to abnormal amounts of albumin in the urine that is below the level detected by urine dipstick

Question 11

What is microalbuminuria an early expression/warning sign for?

Answer 11

Diabetic nephropathy