Understanding your blood results

As kidney patients you will have numerous and regular blood tests. You may view be presented these in different ways depending on whether you dialyse at home, on a ward or a satellite unit. This page covers some of the blood results which are most relevant to you. It includes information about what the results mean and a rough guide to the normal range. Your blood results will change as your kidney function alters.

 Some patients may be able to view their result on an online system called PatientView.

Estimated glomerular filtration rate or eGFR

Your kidney function will be measured using estimated  glomerular filtration rate or eGFR. This is the rate at which blood is filtered by the kidneys and can be referred to as the percentage of normal kidney function. The normal is about 100 in young adults. Kidney function decreases with age so many healthy people in their 80s will have an eGFR of 40-50.

This table shows the likely treatment you will need depending on your eGFR results.

eGFR

CKD Stage Treatment

90 –100

Stage 1
  • Annual blood, urine and blood pressure tests
  • Adopt healthy lifestyle

60 – 90

Stage 2
  • Annual blood, urine and blood pressure tests
  • Adopt healthy lifestyle
30 – 60 Stage 3
  • Annual blood, urine and blood pressure tests
  • Adopt healthy lifestyle
15 – 30 Stage 4
  • Regular attendance at kidney clinic
  • Start learning about treatment choices for kidney failure

Less

than 15

Stage 5
  • Start treatment for kidney failure: dialysis, transplant or conservative management

 

Bicarbonate

acceptable range: 21-30mmol/l

When kidneys do not work properly, acid can build up in your body. This can cause the bicarbonate level in your blood to drop which is bad for your heart and may also hasten the deterioration in your kidney function. This can be treated with medications.

Calcium

normal range: 2.2 – 2.65 mmol/l

Calcium is important for healthy bones and so your nerves and muscles work properly. High and low levels of calcium can be harmful to your bones and your heart. You may be prescribed medications to keep your bones healthy.

Cholesterol

normal range: less than 5mmol/l

Cholesterol is a fatty substance found in the body. Increased cholesterol levels can cause narrowing of the blood vessels.

Ferritin

normal range: greater than 150ug/l

Ferritin is the amount of iron you have in your body. You need iron to make red blood cells and keep your Hb at the correct level.

Haemoglobin (Hb)

normal range: 12 – 15g/dl for women and 13 – 17g/dl for men.

Hb is a measure of how many red blood cells you have in your body. If you are anaemic you will have low levels of Hb which can make you tired and short of breath. In CKD if your Hb level falls to 11g/dl, treatment to correct anaemia will be recommended.

Phosphate

normal range: 0.8 – 1.5mmol/l

Phosphate is a mineral found in your body and in many foods. In kidney disease, your blood phosphate levels can rise which can cause weak bones, itching and problems with blood vessels, joints or muscles. It may be necessary to reduce the phosphate in your diet. Phosphate-binding medication may also be  prescribed to help lower phosphate levels.

Potassium

acceptable range: 3.5 – 5.5mmol/l

Potassium is a mineral found in your body and in many foods. Your kidneys control the amount of potassium in your blood. In kidney disease, you lose this control. Too much or too little potassium can affect your heart beat, so you may be advised to decrease or increase (less common) the potassium in your diet.

PTH (parathyroid hormone)

acceptable range: 10-65 ng/l

This is a hormone made by small glands in your neck which helps in the control of calcium and phosphate in your body. It can rise in kidney disease and this can result in problems with your bones and bone pain. You may be prescribed medications to help control this.

If you have any concerns about your blood results, please do not hesitate to ask a member of the kidney team for advice.