Renal Function Testing

Question 1

Normal urine should be?

Answer 1

1. Clear, amber coloured fluid
2. 95% water, 5 % dissolved solids
3. Contain metabolic wastes
4. Should not contain protein, blood cells or glucose

Question 2

What is the specific urine gravity test?

Answer 2

Indicates the kidneys ability to concentrate urine

Question 3

Urine composition?

Answer 3

Proteinuria and microalbuminuria indicate abnormal filtering or defects in reabsorption.

Question 4

24 hr Urine samples can be used to?

Answer 4

Calculate Glomerular Filtration Rate (GFR)

Question 5

An increase in Plasma creatinine indicates?

Answer 5

Poor renal function and decreased eGFR

Question 6

What is GFR?

Answer 6

Volume of fluid filtered from the glomerular capillaries into the Bowman’s capsule per unit time

Question 7

How is GFR calculated?

Answer 7

BY measuring any chemical that has a steady level in the blood, & is freely filtered, but neither reabsorbed nor secreted by the kidneys

Question 8

Equation for GFR?

Answer 8

Urine concentration x Urine flow / Plasma concentration

Question 9

What is creatine?

Answer 9

Produced naturally by the body & is freely filtered by the glomerulus, BUT also actively secreted by the peritubular capillaries in very small amounts which results in creatinine clearance overestimating actual GFR by 10 - 20% but ok due to ease of measurement

Question 10

What is the Normal range of GFR, adjusted for body surface area?

Answer 10

100-130 ml/min/1.73m2

Question 11

Most labs now report an eGFR which is calculated from?

Answer 11

The serum creatinine level

Question 12

All of the estimating equations depend on a prediction of the?

Answer 12

24-hour creatinine excretion rate, which is a function of muscle mass

Question 13

Patients will generally present for kidney disease due to? (3)

Answer 13

1. Abnormality on routine blood test or urinalysis
2. A symptom or physical sign
3. Presence of systemic disease with renal involvement
   Knowledge of clinical history is an important aid in diagnosis and treatment

Question 14

Diet Interventions When On Dialysis?

Answer 14

1. Decreases water (replace insensible loss only)
2. Decreased protein, potassium and salt

Question 15

Which nutrients may patients with end-stage kidney disease have?

Answer 15

1. Protein - low levels can lead to retention & weak immunity
2. C & B vitamins
   Remember - individual patients have individual dietary requirements dependent on stage of kidney disease, blood test results and type of dialysis if an

Question 16

Phosphate works with?

Answer 16

Calcium

Question 17

High levels of phosphate lead to?

Answer 17

Itch and in the long term can damage blood vessels

Question 18

Phosphate is difficult to remove when kidneys are failing & as a result?

Answer 18

Phosphate levels will increase and phosphate binds calcium, decreasing calsium levels

Question 19

Hypocalcamia causes what?

Answer 19

 Increased capillary permeability
 Neuromuscular excitability
 Decreases blood coagulation
 If severe, tetany can result
 Chvostek’s sign- contraction of facial muscle in response to light tap on facial nerve
 Trousseau’s sign- carpal spasm induced by inflating a blood pressure cuff

Question 20

Anemia can develop from?

Answer 20

Low erythropoietin (EPO) levels, & deficiencies in iron & folate – treatment with each of these can be effective

Question 21

Anemia can lead to?

Answer 21

Platelet abnormalities, metabolic acidosis, electrolyte imbalances, infertility, yellow-gray skin, and hypertension