Kidney and Urinary Tract Disease - Test of Renal Function

Question 1

Kidney function

Answer 1

Excretion (uric acid), regulation (homeostasis, water, acid base), endocrine (renin, erythropoietin)

Question 2

Kidney function

Answer 2

Excretion (uric acid), regulation (homeostasis, water, acid base), endocrine (renin, erythropoietin)

Question 3

Urine volume

Answer 3

750-2000ml/24hr

Question 4

Oliguria

Question 5

Anuria

Question 6

Polyuria

Answer 6

> 3000

Question 7

Plasma urea

Answer 7

Quick, simple measurement, 3-8mmol/L (sensitive)

Question 8

Urea excretion

Answer 8

Filtered at glomerulus, 40% reabsorbed, if slow tubular flow more reabsorbed (renal hypo perfusion)

Question 9

Causes of increased plasma urea

Answer 9

GI bleed, trauma, renal hypo perfusion (decreased RBF, ECFV), acute renal impairment, chronic renal disease, post-renal obstruction calculus tumour

Question 10

Urea

Answer 10

Useful, must be interpreted with great care, always consider input, out and patient’s fluid volume

Question 11

Plasma creatinine

Answer 11

50-140umol/L, increases in conc as GFR decreases (NOT proportional to renal damage)

Question 12

Creatine clearance

Answer 12

Ucreat X V/Pcreat

[RR 100-130 mL/min]
incomplete collection/unreliable

Question 13

Tubular secretion of creatine

Answer 13

Increased in chronic renal disease and decreased by drugs (salicylate, cimetidine)

Question 14

Pre-renal oliguria

Answer 14

GFR reduced, ADH increased, renal hypo perfusion causes renin secretion (increase Na reabsorption)

Question 15

Low renal perfusion caused by

Answer 15

Dehydration, haemorrhage, renal artery damage, hypotension

Question 16

Renal oliguria

Answer 16

GFR reduced/normal, weak urine/low volume, renal renin secretion may be raised (hypertension, unable reabsorb Na)

Question 17

Intrinsic damage causing renal oliguria

Answer 17

Tubular necorsis, chronic infection, immunological damage (SLE), toxic damage (drugs, heavy metals Hg, Ur, poisons)

Question 18

Lab tests of renal function

Answer 18

plasma creatinine
plasma urea
plasma sodium
urine volume
urine sodium
urine urea
creatinine clearance
urine dispsticks

Question 19

Problem with GFR

Answer 19

Impractical

Question 20

Problem with CC

Answer 20

Unreliable

Question 21

Problem with plasma creatine

Answer 21

Specific, but insensitive

Question 22

Problem with plasma urea

Answer 22

Subject to problems

Question 23

Problem with urine vol

Answer 23

Often forgotten

Question 24

Urine volume

Answer 24

750-2000ml/24hr

Question 25

Oliguria

Question 26

Anuria

Question 27

Polyuria

Answer 27

>3000

Question 28

Plasma urea

Answer 28

Quick, simple measurement, 3-8mmol/L (sensitive)

Question 29

Urea excretion

Answer 29

Filtered at glomerulus, 40% reabsorbed, if slow tubular flow more reabsorbed (renal hypo perfusion)

Question 30

Causes of increased plasma urea

Answer 30

GI bleed, trauma, renal hypo perfusion (decreased RBF, ECFV), acute renal impairment, chronic renal disease, post-renal obstruction calculus tumour

Question 31

Urea

Answer 31

Useful, must be interpreted with great care, always consider input, out and patient's fluid volume

Question 32

Plasma creatinine

Answer 32

50-140umol/L, increases in conc as GFR decreases (NOT proportional to renal damage)

Question 33

Creatine clearance

Answer 33

Ucreat X V/Pcreat | [RR 100-130 mL/min] incomplete collection/unreliable

Question 34

Tubular secretion of creatine

Answer 34

Increased in chronic renal disease and decreased by drugs (salicylate, cimetidine)

Question 35

Pre-renal oliguria

Answer 35

GFR reduced, ADH increased, renal hypo perfusion causes renin secretion (increase Na reabsorption)

Question 36

Low renal perfusion caused by

Answer 36

Dehydration, haemorrhage, renal artery damage, hypotension

Question 37

Renal oliguria

Answer 37

GFR reduced/normal, weak urine/low volume, renal renin secretion may be raised (hypertension, unable reabsorb Na)

Question 38

Intrinsic damage causing renal oliguria

Answer 38

Tubular necorsis, chronic infection, immunological damage (SLE), toxic damage (drugs, heavy metals Hg, Ur, poisons)

Question 39

Lab tests of renal function

Answer 39

``` plasma creatinine plasma urea plasma sodium urine volume urine sodium urine urea creatinine clearance urine dispsticks ```

Question 40

Problem with GFR

Answer 40

Impractical

Question 41

Problem with CC

Answer 41

Unreliable

Question 42

Problem with plasma creatine

Answer 42

Specific, but insensitive

Question 43

Problem with plasma urea

Answer 43

Subject to problems

Question 44

Problem with urine vol

Answer 44

Often forgotten