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BRITISH BROADCASTING CORPORATION
RADIO SCIENCE UNIT
CASE NOTES
Programme 7. - Kidneys
RADIO 4
TUESDAY 21/02/06 2100-2130
PRESENTER:
MARK PORTER
CONTRIBUTORS:
JOHN SCOBLE
NEERJA JAIN
JULIE HARRIS
DAVID TAUBER
NADEY HAKIM
PRODUCER:
ERIKA WRIGHT
NOT CHECKED AS BROADCAST
PORTER
Hello. Today's programme is all about kidney failure and how to spot, prevent and treat it.
Kidney units in some part of the country are experiencing a 10% year-on-year rise in the number of patients they look after with end stage kidney failure. Why is it becoming more common?
I'll be finding out why people of Asian and Afro-Caribbean origin are up to five times more likely to develop kidney trouble and eavesdropping on a new initiative to help address the problem.
And would you be prepared to donate one of your kidneys to help a member of your family? When William MacDonald found out that his wife Anna needed a new kidney, and that he could be a suitable donor, he didn't hesitate before offering her the ultimate gift.
ANNA MACDONALD
We didn't actually know about being unrelated that you could use someone else's kidney, we thought it had to be a family thing. And he just happened to ask at the clinic one day and I was taken aback because I didn't - we'd not discussed it. He says if you could use my kidney would you have it? And he says well we'll try all the tests and things and it came back that the blood group was incompatible. And then a couple of weeks later they says we can do it because we've now got a - we're trying a new operation that has been twice and it was successful. And the option was there as to whether we wanted to try it or not. And we did.
WILLIAM MACDONALD
It is a wonderful gift that I'm giving to Anna, it's not something you can - no matter how rich you are you can't walk into a shop and buy it. And I just hope it all goes well for us.
ANNA MACDONALD
And I mean I can't thank William enough, I've got no words to say to William because there isn't a word to express myself really, it's just wonderful and it's such an opportunity for other people out there to do and just do it, do it.
PORTER
Well William did, and I am pleased to report that the operation was a success. I'll be talking to the surgeon who did Anna's transplant later on.
My studio guest today is Dr John Scoble, a kidney specialist at Guy's and St Thomas' Foundation Trust in London.
John, before we start discussing what happens when kidneys fail, what functions do they perform when they're working properly?
SCOBLE
Well what they do is they clean our blood. What most of us don't realise is during the day they will produce about 360 pints of urine but will reabsorb all that fluid except about one or two pints we pass. So the amount of work they're doing all the time when we're sleeping, we're walking around is phenomenal. But the other interesting thing is we don't realise that they also control our blood pressure, if they go wrong our blood pressure goes up. If the kidneys don't work well the hormone called erythropoietin doesn't make our bone marrow make red blood cells, so we become very anaemic. And if the kidneys go wrong the active hormone that keeps our bones strong goes away and we have very severe bone disease. So although we think of it as producing a small amount of urine each day what the kidney is doing is a phenomenally complex process of which we only really understand a little bit about it when it all goes wrong.
PORTER
And what are the main threats to our kidneys in terms of long term disease, obviously there are things that can happen suddenly to people and cause acute kidney failure but I want to dwell on things that are going to happen slowly and subtlely over a life time really?
SCOBLE
There are a number of families who may have a kidney disease within the family - polycystic kidney disease is one of those - and that may be passed down through families. But if you were to look at the whole of the United Kingdom the really two big threats are high blood pressure and diabetes and this applies probably across the rest of the world.
PORTER
And they're damaging the kidneys how?
SCOBLE
The kidneys are three million little filter units, they're incredibly sensitive pieces of equipment and anything that over-stresses them will cause these filter units to clog up. And essentially that's what happens in diabetes. And if you think about a filter with extra high blood pressure going through it then that's going to damage it and it's two litres of blood every minute will go through the kidney and it's got to be filtered all the time.
PORTER
Who's at particular risk of kidney failure?
SCOBLE
Within different groups within our communities, certainly in the Asian group with diabetes and the African and Caribbean group with high blood pressure, the specific areas where these are really very difficult problems.
PORTER
And are they more common because high blood pressure and diabetes are more common in those groups?
SCOBLE
Diabetes and blood pressure seem to be more common and more severe, people in those groups seem to be able to go on to dialysis much more quickly than patients who may be Caucasian.
PORTER
Well, that increased risk of kidney failure among certain ethnic groups is often compounded by poor awareness of the risks - both among the communities and the health professionals that serve them. Something renal nurse Neerja Jain is hoping to address with the community based ABLE project in Leicester, which uses peer educators - trained lay people - rather than doctors and nurse - to spread the word. We dropped in on one of the sessions - and even though I don't speak Punjabi I managed to recognise a few of the terms.
ACTUALITY - ABLE PROJECT
As we all know kidney disease can be any age, anybody can be at risk of kidney disease. First of all people who suffer from high blood pressure and diabetes are more high at risk. So if you suffer from high blood pressure or diabetes and you are not on any medication you have to go to your GP and have yourself tested.
Thank you very much - it was enlightening what you said. Can this be a familiar or a genetic condition which can go in the families, run in the families?
Yes it can be but mostly it's people who suffer from high blood pressure or diabetes, they're more high at risk.
JAIN
These communities are anywhere between three to five times more at increase of renal failure than the white European community. We know there are a number of reasons for renal failure but we know that in these communities Type II diabetes and hypertension are the two main culprits.
PORTER
And what's awareness like amongst those communities - I mean do they know that they're at increased risk of kidney disease?
JAIN
Some of our research in awareness strategies over the last couple of years or so have revealed really what we suspected, which is that there is very little awareness, if any at all, in these communities. But this also ties in with something else that we suspected which is that we know sometimes the health professionals serving these people at risk are also unaware of the huge issues and problems.
ACTUALITY - ABLE PROJECT
What I want to know is say I'm suspecting something's wrong in my body and I think it might be my kidney, I have been to the doctor a few times before, what can I say to him that will actually prompt him to say yes you do need this test, what's the strongest words I can use to convince him that I do need help because half the time the doctors don't want to really know?
If you feel you're feeling unwell and you feel you suspect there's something wrong with your kidney you are entitled to go to your GP and have your urine tested and then if there is a problem there they will test your blood. And then it's carried to further tests - carried out like scans and so on to find out if you really suffer kidney disease.
So I can go to the doctor and say look I insist on having this, will that be in my right?
Yes you are, you are entitled to. So you can go to the GP ...
JAIN
Peer educators are people from within the local communities, they're lay members of the public, and really the idea is pretty fantastic we feel because we're empowering these people, who have the greater empathy with these communities, to deliver vitally important health messages in a way that we believe health professionals would not be able to do.
PORTER
Have you any evidence that the communities are more receptive to messages from their own peers?
JAIN
We know certainly in Leicester a similar model was developed during a project dealing in the primary prevention of coronary heart disease and that was very well received, so we felt that a similar model for renal health promotion could be easily replicated. And when we do go out to the communities we get feedback from the communities and this has been overwhelming actually, I mean this is the kind of information they want in the manner in which they want it - they don't want leaflets, they'd much rather that a personal approach by a peer educator giving them a presentation, answering their questions, and from the communities' point of view for individuals to take appropriate lifestyle changes in order to avert their risk of kidney disease.
PORTER
And what lifestyle changes are you referring to?
JAIN
We know that maintaining a healthy weight, not smoking, eating a well balanced diet and drinking two litres of fluid are all ways of keeping your kidneys healthy.
PORTER
Neerja Jain talking to me in Leicester.
You are listening to Case Notes, I am Dr Mark Porter and I am discussing kidney failure with my guest Dr John Scoble.
John, awareness isn't just a problem among some ethnic groups is it?
SCOBLE
No, we've been doing some work locally in Lambeth and Southwark and found a big issue about young men. Women often will go to see their GP for lots of other reasons but men often don't go and they're a group in whom high blood pressure can be a very specific problem.
PORTER
And a silent one as well.
SCOBLE
The problem is people don't know, they only get symptoms of kidney disease when they lose 80% of their kidney function and all of us have patients who come along when they've got to that stage and there's little we can do. So often it's picking up in other ways, like your blood pressure's a little high, or maybe you've wanted to join a gym and it's been found to be high, your urine's been tested because you changed general practice - these are very non-specific ways.
PORTER
Okay well let's look at the medical tests, I mean how would we do it medically?
SCOBLE
Well two things. One is to look at the kidney function we measure a waste product in the blood called Creatinine. And the second is to see whether those little filter units are leaking either blood or protein into the urine and if that's the case then we need to look at it very carefully.
PORTER
And there are some significant changes coming in the way that the standard kidney test is reported isn't it, at the moment I get a set of figures but that's going to change as of April?
SCOBLE
Yes, I have to say the big problem with a set of figures is nobody can, as a patient remember, whether the creatinine should go up or down. What we're going to do in the first of April is do a calculation from the waste product level and the value will come out at something which we'd all recognise as being a percentage - the normal for you and I would be 80-100, if it's zero it's terrible, so if your kidney function's 50% your number will come out at 50. And I think patients are really going to understand where they fit in the range of kidney function.
PORTER
So are GPs I expect. But what can we do, if we identify someone has having 60% of normal renal function what can they do and more importantly what can I do as the doctor to preserve and protect what function they've got left?
SCOBLE
Well I think the important thing to remember is we do all lose a little bit of kidney function with age, about 1% per year after the age of 40, so it will gradually go down with age. But as Neerja just said the big issues are control of blood pressure, control of diabetes, stopping smoking, healthy eating, healthy living. The interesting thing is these are factors which will stop all of us getting strokes, all of us getting heart attacks. So a lot of us are now coming round to think of people with kidney function that's not perfect as having risk factors for the future. Certainly in America it's been shown that in the group you've just described, say 60%, those people are more likely to have a stroke than they are to have kidney failure needing treatment in the long term. So healthy living is be all and end all.
PORTER
For managing all of your risk factors. But what are the options when we get to a stage where the kidneys can no longer cope?
SCOBLE
I think there are three options. The first is a transplant, and if you've got a donor I'd be on very good terms with your brother or sister or spouse. The second is dialysis treatment. And one option for the elder group of patients who may not wish to go ahead is supportive therapy without dialysis treatment, a palliative care approach.
PORTER
Well we'll come back to transplantation a bit later, but first dialysis. Hammersmith Hospital in London has just opened a new renal centre which includes a state-of-the-art dialysis unit. I went along to find out what's involved.
HARRIS
My name's Julie Harris, I'm the lead nurse for renal services within the West London Renal and Transplant Department, based at the Hammersmith Hospital. We're currently in our acute haemodialysis unit, which is a 23 stationed unit.
PORTER
It looks a bit like a modern intensive care unit. There's telephones and there are alarms going off left, right and centre. Presumably the machines require quite close monitoring.
HARRIS
Yes they do and as you can hear the alarms are going off, maybe that there's a blockage or an occlusion in the pumps or there may be a blockage within the actual blood line itself, which may mean that they need to have some blood thinning to make sure that it all works properly.
PORTER
And how long would a typical patient be here for - on the machine?
HARRIS
Sometimes we do short dialysis to get somebody ready for theatre, so they might only be here for two hours. But they could be here up to five hours.
FRED
My name is Fred and I'm 67 years old.
PORTER
When did you first find out there was a problem with your kidneys?
FRED
I've had problems for a number of years and I actually found out in 1982 and they told me then that I had polycystic kidneys, which my mother had given me, actually, which I'm not too happy about.
PORTER
Having polycystic kidneys puts you at risk of kidney failure early on but presumably in 1982 your kidneys were still functioning alright. When did you first need dialysis?
FRED
Three years ago because they'd really packed up working completely.
PORTER
How did you feel about that?
FRED
Quite upset actually, it was a bit of a shock to the system. I have dialysis three times a week.
PORTER
And for how long each time?
FRED
Four hours.
TAUBER
My name is David Tauber. I'm a consultant nephrologist and for my sins I run the West London Renal and Transplant Centre.
PORTER
David, dialysis is obviously a complex procedure but in a nutshell can you explain what's happening?
TAUBER
Fred is currently on haemodialysis, he's connected up to the dialysis machine via two lines and these are tunnelled under his skin, just below his collarbone, and they enter his venous circulation via the right internal jugular vein and then into his right atrium.
PORTER
So when Fred's not connected to the machine he would walk round with those tubes there ...
TAUBER
He does.
PORTER
... permanently into his neck veins?
TAUBER
He does. And because they're tunnelled this reduces the risk of infection.
PORTER
So presumably the blood is coming out of one line and returning via the other and in the meantime it's going round this complicated machine.
TAUBER
That's right. This complicated machine is basically a pump which has various valves and pressure detectors, so if, for example, there was a leak, the machine would sense a reduction in pressure and it shuts down.
PORTER
How much - there's quite a lot of blood actually outside of Fred there, which is all going back into him, and you can imagine if there was a leak it could be pretty catastrophic.
TAUBER
It could be absolutely catastrophic and in the early days when machines didn't have the appropriate alarms and devices and sensors people did occasionally [indistinct word] on the floor.
PORTER
So the process of dialysis, is it principally about removing toxins that have accumulated in the body?
TAUBER
That's right. Two things the dialysis machines does in general. The first is obviously, as you quite rightly allude to, it's the removal of metabolites normally excreted by the kidney, things like urea, creatinine, nasty toxic irons like potassium, regulates your sodium. And also very importantly it removes water. There's a little part of the machine here called the dialysiser and this is a very cunning device. In the old days we used to use large sheets of polythene and this cylinder consists of several thousand very thin tubes of a type of polythene through which the blood runs, as you can see it goes from top to bottom, and these little very fine tubes of polythene are bathed in the dialysate solution, which is pumped round the machine, and as the blood goes through the various molecules, such as urea, potassium and sodium, come out via convection process into the dialysate.
PORTER
So effectively the polythene is acting as a screen between the blood and the dialysing solution?
TAUBER
That's right.
PORTER
What drives the bad things, if you like, from the blood through the membrane and into the dialysing fluid?
TAUBER
The concentration of urea, sodium and potassium in the dialysate is purposely very low. So it's a longer concentration gradient for those substances.
PORTER
Are patients aware of when they need dialysis?
TAUBER
Very much so. Many patients become very acutely and sensitively aware of the fluid balance in their body and also when the build up of certain substances like potassium occurs. They become weak, if you raise your potassium you become effectively paralysed. They're also acutely aware of the fact when they fill up with fluid - they become short of breath, they're unable to lie flat and of course they notice that their shoes are more tight to put on.
PORTER
What about afterwards - do they get immediate relief from those sort of symptoms?
TAUBER
In terms of the fluid overload they do. Now if they've had a long and difficult dialysis they may feel - it's a bit like having a hangover.
FRED
There are times when you get fairly - fairly low and also what goes with it is the despondency, I can get quite upset at times about it but I try not to think about it too much really.
PORTER
Have you ever missed a dialysis session?
FRED
Yes.
HARRIS
There are some patients that do miss sessions for various reasons but sometimes because they feel well and so feel that it's okay to miss that session.
PORTER
But presumably missing a session of dialysis could potentially be quite dangerous?
HARRIS
It could do, they could then, depending on whether they adhere to their fluid restrictions during that time, could end up being fluid overloaded and need to come in for urgent or emergency dialysis. And of course if they continually miss dialysis sessions in the end it could prove to be fatal.
PORTER
Out of the 23 stations that you've got here I can see there's only one empty, presumably you run close to full capacity the whole time.
HARRIS
Yes we do on the whole.
TAUBER
We basically have to provide a hundred new places on haemodialysis every year. And we've been doing this for the last 10 years and if you look at our figures and data we're faced with doing this every year for the next 10 years.
PORTER
And a hundred places represents what sort of percentage of your workload?
TAUBER
That represents one tenth of our workload. We've got well just under one tenth. At the moment we've got 1200 patients on haemodialysis in West London.
PORTER
David Tauber talking to me at the Hammersmith.
John, I was surprised by that rate of increase - increase in demand for dialysis - nigh on 10% per year. Is that indicative of a similar rise in the incidence of kidney failure?
SCOBLE
Yes and I think it's a liberalisation of the way we use dialysis treatment. When I started off 20 years ago we didn't dialyse people with diabetes. I've now got two people who are over 90 years of age on dialysis treatment and if it improves their lifestyle then that's perfectly reasonable. But maybe these are groups we didn't have before. David says about 10% for his area, which has got special needs with the local ethnic groups he has in West London. I think for most of us 7-10% is what we would see.
PORTER
So part of that must reflect that kidney failure's becoming more common. If so why?
SCOBLE
I think we're more aware of it, we're able to give the treatment and there are certain groups - the Caribbean group that came over maybe in the early 60s is getting older and that group is having a much higher incidence of kidney disease in certain areas of the country.
PORTER
Going back to dialysis. Having three to four sessions a week, presumably is something of a compromise because our kidneys are designed to work 24 hours a day, seven days a week. Is that something we do because of lack of resources?
SCOBLE
Well can I ask you how much kidney function does that give you?
PORTER
I don't know I'm asking.
SCOBLE
It's interesting because actually the patients will often say 50%, it's 10% of normal kidney function you get. Now I think for younger patients who may be able to do it themselves then I'd love them to be on longer hours. What David has suggested is our experience is that for older patients tolerating four hours three times a week is sometimes quite difficult, so that if you're a younger patient yeah I'd love them to be on longer hours but I'm actually not sure we can offer it to everyone in that they'd tolerate it.
PORTER
What about permanent dialysis - is there anything in the pipeline where we're looking at smaller machines that can be left on the whole time that might be portable for instance?
SCOBLE
Well we've just looked at a programme in Holland in which people do eight hours six nights a week and interestingly the machine is a standard machine. Those patients come back to us and say it's fantastic because they can drink as much as they like, they can eat as much as they like but it's only really for people who'd be able to do it at home, which is always going to be a small number.
PORTER
And a regime like that would give you what sort of percentage of kidney function?
SCOBLE
Possibly 30%, this is really good kidney function, oh yeah.
PORTER
Still way down though on what a normal person would have.
SCOBLE
Way down but not at the level you start dialysis treatment because you only start dialysis at about 15 to 10.
PORTER
Let's move on to transplantation now. Is it offered to all patients with kidney failure?
SCOBLE
Transplant is quite a big procedure and I think if you've got multiple medical other problems, which as we've heard a lot of patients have, then the risks of transplantation may outweigh the potential benefits. So we try to offer it for those patients who we feel would be at benefit and the risks of the operation would not be too extreme. We do feel however that for people who have a living donor transplant in which we can really set it up in advance that maybe we might transplant people a little bit more at risk than if they were to wait for a kidney to come up from the national scheme.
PORTER
How do long term survival rates compare between someone who has a transplant and someone who may be through their own choice decides to carry on having dialysis?
SCOBLE
The long term survival rates are much better for transplantation than remaining on dialysis and interestingly, as I think lots of us now recognise, even if you only spend six months on dialysis treatment your outcome if you get a transplant after that is worse than if you never had dialysis treatment.
PORTER
So what you're saying is that even six months delay on dialysis can affect the chances of a successful transplant.
Well earlier I caught up with another Mr Nadey Hakim, he's the surgical director of the Transplant Unit at St Mary's Hospital in London. And you'll remember that at the beginning of the programme we heard from William McDonald, who donated a kidney to his wife Anna. Well Nadey Hakim was the surgeon responsible for that operation and as I discovered, using kidneys from live donors, rather than from dead ones - known as cadaveric donors - is now increasingly common. And the best outcomes are in pre-emptive transplants - where the recipient is given the new kidney before his own kidneys pack up completely.
HAKIM
Pre-emptive transplantation has been shown to be definitely an advantage. Why? Because first of all the recipient is going to be healthier by the time he gets the kidney. Second, the kidney function is going to be better immediately after the transplant compared to a cadaveric, which by the finish is going to be in an ice box for a few hours compared to a pre-emptive transplant done from a live related donor for instance, which is going to be much quicker. And more importantly you are going to be able to select the donor and the recipient in a much more efficient way to make sure that the recipient, who is not in a hurry that much to get a transplant, gets the best possible available kidney on that day.
PORTER
That obviously makes a lot of sense but given that there are some five and a half thousand British patients at the moment waiting for transplantation and only I think 1700 of whom had a transplant last year, most people who are on the list will not get given a kidney so is it actually a realistic option that you can hope to transplant people before they've gone into failure?
HAKIM
The majority will end up on dialysis but if we try to inform the population and the public that trying to find a family member to donate and making it more popular than it has been so far then obviously we will end up transplanting many more patients early and not have them on dialysis. If you look at the figures 20 years ago we did not transplant anyone from a live related donor. Now I can tell you that the majority, over 50% of our transplants, are from living donors. In other words things are changing.
PORTER
Does it make much difference which ethnic group a patient is from in terms of the likelihood of him finding a live donor within his family, are there different perceived values about whether this is a good thing to do or a bad thing to do?
HAKIM
Kidney failure is unfortunately genetic, meaning that families run into kidney failures. In other words if you ask someone who is on dialysis or having a failing kidney to have a transplant from a live donor you have to make sure that that live donor is not himself or herself about to get into kidney failure too. So this is the number one problem with the ethnic groups. Second, the majority of donors in the country are by definition going to be white Caucasian and therefore the blood group and the HLA - which is the tissue type of those donors - are more likely to be close to the white Caucasian recipient than the ethnic patient. Therefore, they tend to wait much longer.
PORTER
Would you ever consider putting a Caucasian North European kidney into someone of say South Asian origin?
HAKIM
Absolutely. The necessity of having a perfect match is not too important anymore because of the much better immunosuppressive drugs and the success rate has improved tremendously. And you can indeed put an Afro-Caribbean kidney into a white Caucasian and vice versa.
PORTER
Surgeon Nadey Hakim.
Interesting point John, Nadey made there about advances in immunosuppressive drugs - those are the medicines used to prevent rejection of the new kidney. I'd always thought that Asians and Afro-Caribbeans faced something of a double whammy, not only are they the most likely groups to get kidney failure but when they need a transplant they're the least likely groups to be able to find a suitable organ. Is what you're saying that the latest drugs have changed all of that?
SCOBLE
Well I think one of the big problems is the allocation system will try and match people up and that's a disadvantage for the groups you said. What Nadey's now saying that irrespective of tissue type, even for blood group, which 10 years ago we thought was something we should never ever do a transplant with the wrong blood group we're now doing, as Nadey was talking about just now. I think the new immunosuppressive agents have revolutionised the range of patients we can transplant into and patients we can transplant from.
PORTER
And presumably once you start on a regime of drugs you're taking them - are they lifelong regimes?
SCOBLE
They're lifelong, we obviously reduce the doses after the initial period but yes, and this is a major problem because they do have their own side effects. But the potential benefit in the long term is phenomenal.
PORTER
John Scoble, we must end it there. Thank you very much.
Don't forget, if you have access to the internet you can listen to any part of the programme again by visiting our website at bbc.co.uk/radio4. Next week
I'll be looking at NHS out-of-hours services - where do you go, and who do you call, when your local GP surgery is shut?
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