Living with one kidney can cause anxiety, but the reassuring message is that the remaining kidney steps up and takes up the workload.
‘It’s perfectly feasible and in fact very common to live with one kidney without it causing any problems at all,’ says Professor Alan Salama, a consultant nephrologist at the Royal Free London NHS Foundation Trust.
Reasons why you might have one kidney
There are three main reasons why you may have one kidney.
You are born with just one kidney
Renal agenesis, or having a single kidney, can be picked up on an antenatal ultrasound scan, but a lot of people are unaware they have the condition and it’s diagnosed later in life during a routine scan or X-ray. Around 1 in 1,000 to 2,000 babies are born with one kidney.
You have had a kidney removed due to a disease or an injury
‘The top three reasons for having a kidney removed (called a nephrectomy), would be kidney cancer, kidney stones that have got too big and may be recurrently infected, and infectious complications,’ says Professor Salama. Other reasons for kidney removal include accidents and injuries.
There are 13,300 kidney cancer cases in the UK every year and surgery to remove a kidney or part of it is the main treatment.
You’ve donated a kidney through the living donor transplant scheme
Around a third of the 3,000 or so kidney transplants performed every year in the UK are from living donors.
How can one kidney do the work of two?
One kidney is enough to filter your blood and keep it clean and healthy. ‘Your remaining kidney can get bigger and increase its workload quite significantly,’ explains Professor Salama.
‘If someone has a kidney removed then their kidney function will drop from 100 per cent to 50 per cent, but they often end up with kidney function which is 75 per cent of what it was pre donation because the remaining kidney is working harder and compensating for the loss of the other.’
The overall risk of developing significant kidney disease is less than 1 in 200 in people who have donated a kidney, with a 15-year risk of kidney failure of less than 1 per cent for most people, and this is less than in the general population.
What medical care can you expect if you have one kidney?
‘It’s really important that you look after your remaining kidney, so you should have regular check-ups to check your kidney function is normal,’ says Professor Salama. ‘You can be managed by your GP but may see a nephrologist if there is a problem.
‘You need to have regular (once a year) kidney function blood test and have your blood pressure monitored, plus urine tests to check you are not leaking protein in your urine, which can all be markers for loss of kidney function.’
My specialist reassured me the remaining kidney would be able to cope and I could still live a normal life. Weirdly, I was more worried about losing something that had always been a part of me than the cancer. I was worried about living with just one kidney, but my remaining kidney’s function is fine. I have regular blood tests to measure the estimated glomerular filtration rate (eGFR), a score for how well your kidneys are functioning.Louise Gartside, 49, who lives in Cambridge with her two children, had a kidney removed after being diagnosed with kidney cancer
Self-care for kidney health
- Take steps to lower high blood pressure.
- Reduce your salt intake if it’s more than 6g a day.
- Avoid taking non-steroidal-anti-inflammatory painkiller drugs (NSAIDs) such as ibuprofen and diclofenac, as they reduce blood flow to the kidneys.
- Exercise – studies have shown it can improve kidney function.
- Don’t smoke – it can raise your risk of cancer and damage blood flow to the kidneys.
- Eat a healthy, varied diet.
- If you have reduced kidney function, always check with your doctor, pharmacist or kidney health team if herbal and complementary supplements are safe to use.
What potential problems could develop?
The good news is that most people with one kidney have a normal lifespan and can live normal healthy lives.
‘The remaining kidney can compensate, but in some cases if it works too much it’s a little bit like a light bulb filament burning out too quickly,’ says Professor Salama. ‘Some of the signs this is happening are raised blood pressure and protein in the urine, which is why it’s so important to have check-ups.
‘If you do develop kidney dysfunction there are so many new treatments now that can stop progression. Some of the newer drugs such as SGL2 inhibitors, which were developed for diabetes, are incredible at slowing down the rate of kidney function decline and are real gamechangers.’
Other kidney damage may occur as a result of an underlying condition such as diabetes or other autoimmune conditions, or an injury or accident.
I don’t feel any different, I can do everything I did before and have no related health problems. I don’t even have to take any medication. In the first year I had to go back to hospital at 12 weeks and then 6 months for check-ups, but since then it’s just been yearly. I have my blood pressure and weight measured and blood tests to check the eGFR.Brenda Poland, 53, lives with her husband Liam in Carryduff, Northern Ireland, with her three children, and donated a kidney to help Liam. The donation was via the UK Living Kidney Sharing Scheme, where if you are not a match for your relative, the pair of you can be matched with another pair (or even two pairs)