Professor Claire Sharpe, Professor of Renal Medicine, King’s College London

Published on: 18 Jul 2022

AUTHORS:  Dr Sanketh Rampes and Dr Anvarjon Mukhammadaminov 

In this series the Medspire team interviews doctors about their career, their specialty, the choices they have made and their advice for doctors and medical students. 

Here the subject is Professor Claire Sharpe, a professor of renal medicine, King’s College London. Professor Sharpe is a national expert in the fields of chronic kidney disease in patients with sickle cell disease.

A podcast of this interview is available here:


How did you get to where you are today?

I went to school in South London - so I'm a local girl to King's - and I went to a state secondary school. At the age of about 13, I decided I wanted to do medicine. I really enjoyed sciences, and knew that I wanted to work with people. 

So I applied to do medicine at UCL where I did an intercalated BSc, and graduated in 1991. I then did various medical jobs, but after my first year as a registrar, I took a year out and went travelling, which was a great experience. When I came back, I did my PhD at King’s. I always knew I wanted to get involved in research.

I set up my own research lab alongside my clinical training, and became a consultant in 2004. I've been really lucky to spend half of my time doing clinical care for patients with kidney disease, and half of my time doing research. I run a basic science research laboratory, looking at the causes of chronic kidney disease and how we might find new therapeutic targets. 

I've always been involved in medical student teaching, but in March 2017 I became a block lead for the Supporting Life Block, and set up a new curriculum. I then took over as head of Stage II in November 2017. So I now have three jobs: I do medical education which I really enjoy, I still run my research laboratory on the Denmark Hill campus, and I still see patients with kidney disease. I consider myself very lucky that I can actually ‘have my cake and eat it’.


What drew you towards renal medicine in particular?

A number of things. Trying to choose a specialty is never an easy decision because all of them have different advantages, and they're all interesting at the end of the day. However, the most important thing about choosing a specialty is to understand that when you get involved in anything in depth, you end up enjoying it. So it's not as big a decision as it may seem at the outset. 

When I was an SHO at Hillingdon Hospital, there wasn’t a renal unit, and a dialysis patient came in who was very unwell, and I was having to look after him. I found it very scary because he had high potassium, was fluid overloaded, and acidotic, and I didn't have the tools to do anything about it. I couldn't make him better. It was either intensive care or send him out to another unit. 

After that, I decided the only way to avoid being in that situation again was to actually go into that specialty and learn about it. So I did a renal job as an SHO and loved it. I loved the mixture of being able to look after the acutely unwell patient. Also, once you're a renal patient you're a renal patient for life. 

So you actually build up really long-term relationships with people. I now have patients that I've looked after for 15 years. I love both aspects of that job - the acutely unwell patient side of things, but also that long-term relationship.


Can you tell us more about your research interest in chronic kidney disease?

Chronic kidney disease is the bread and butter of any nephrologist. There's acute kidney injury and there's chronic kidney disease. With acute kidney injury the kidney function goes rapidly, but most of the time it goes back to normal again. That's because there's an acute process that happens in the kidney, then it heals and repairs and goes back to normal. 

Chronic kidney disease is a disordered healing response to injury. So, just like if you cut your skin, if you have a normal cut it will heal without any scar, but if you repeatedly cut your skin in the same area, or cut it very deeply, it will heal by forming a scar, and that scar is different from the normal skin around it. 

The kidneys - indeed the heart, the lungs, the liver, all of our solid organs - respond to severe or recurrent injury in the same way. They form scar tissue, and that's a physiological response because this tissue is tough and resistant to further injury. 

What scar tissue can't do is function like the healthy tissue surrounding it. Scar tissue in the kidney may be resistant to further injury, but it can't filter the blood, it can't do the function of the kidney. So chronic kidney disease is really defined as the balance between scar tissue and healthy tissue, and the more scar tissue you have, the less healthy tissue you have, and the worse your chronic disease, the lower your function. 

If we define chronic kidney disease by the GFR, which is how it's categorised, the amount of function that your kidneys have is really reflecting how much healthy tissue you have as opposed to how much scar tissue you have. Once you've started initiating injury in the kidney, the way the kidney then alerts to a responding injury is generally through scar formation, rather than through repair and regeneration. 

So what my laboratory is interested in is looking at the cell signals inside the kidney that drive a kidney towards scar formation rather than repair regeneration. If we can understand what forms fibrosis, and can find therapeutic targets to slightly dampen down the scar response, which will enable the normal repair regeneration to occur, we can limit the progression of chronic kidney disease by reducing the total fibrosis burden over time in the kidney. 


Is there one paper or project that you're most proud of?

It is a difficult question because one of the things about running a research laboratory is that you bring junior researchers in, you have PhD students and clinicians doing PhDs, and all of their work is valuable and has added to the knowledge. 

So I'm actually proud of every single paper that's been published with those people, and I can't really pick one out, because each of them is built on what's gone before them. I'm proud of all of the PhD students who have come through my lab, because they've all worked very hard, and all of them came in without having much experience in the field. It’s been a huge learning curve for them and they've all produced something fantastic at the end of it.


During the pandemic, your research was redirected towards COVID patients. Can you tell us about that?

It wasn't really that my research was redirected, I was redirected! My clinical time increased during COVID which is totally appropriate, and it was - an overused word - ‘unprecedented’. But these were unprecedented times. 

There were huge numbers of patients coming in, and the one thing that we didn't anticipate in the first wave was the effect of COVID on the kidneys. The early reports coming out of China, and even Italy, suggested that acute kidney injury wasn't a feature of COVID-19. But it became apparent from mid-March, if not earlier, that patients being admitted in the UK were at high risk of getting acute kidney injury, particularly those that were very unwell. 

Around the end of March-early April, it became apparent that many COVID patients in intensive care were developing acute kidney injury. There was a crisis in the country.  We were running out of resources to deliver renal replacement therapy in the intensive care settings. 

Every intensive care setting has a haemofilter, or a number of people have filters based on the number of patients they predict need treatment for acute kidney injury at any one time. COVID totally overwhelmed that. So there was a period where there were lots of people developing acute kidney injury. 

At King’s College Hospital we used peritoneal dialysis as an acute form of renal replacement therapy on the intensive care unit, as opposed to hemofiltration, or haemodialysis. This approach was quite unique in this country. We set up a service - we've got a fantastic PD team at KCH - and the nurse consultant who runs it puts in the PD catheters at the bedside under a local anaesthetic

We were able to deliver about 50 per cent of the renal replacement therapy needs on intensive care through peritoneal dialysis as opposed to filtration, or haemodialysis, between end of March to end of May last year. This had a huge impact on the service because it freed up those haemofilter machines for other patients. It meant that the intensive care doctors could be much more relaxed about how they were treating these people. 

Having done an innovative piece of work like that, it is really important that you then publish it so other people can see what you've done. You not only publish your work, but you look back on your data, make sure that what you did was of benefit, and that the outcomes were good, and then you share that with everyone. 

So that was more service development than research. Subsequently, we've done pieces of work looking at acute kidney injury as a whole, which we're still trying to work up. But most of the data we publish has been around managing acute kidney injury in the intensive care setting. 

Fortunately, with new medicines and an understanding of how we should treat these patients, acute kidney injury was not a major part of the second wave, so we haven't had to repeat that.


Do you think the use of peritoneal dialysis in intensive care might be translated beyond the setting of COVID?

That's something we've talked about a lot. There will always be some patients where it feels it's the right form of renal replacement therapy. When you go on a haemofilter, for example, you have to be anticoagulated. There may be some patients who don't want to be anticoagulated where PD would be a really good option. 

So we will certainly select patients moving forward. Now that we can do this, we can offer it safely, and the intensivists have got more confident with this form of renal replacement therapy. So it will always be there as a service that we can offer. It's quite resource intensive. You need nurses to know what they're doing and to understand how it differs in an ICU setting, because it's normally a therapy that patients do themselves at home - it's not something that you'd even come up to the hospital for. 

So it's quite a big shift from doing this therapy at home to doing it in intensive care. But it has certainly changed the way we would work, and hopefully that paper will inspire others to consider it, especially if resources are running short. Many lower middle-income countries do use it in that setting in a way that is safe and effective, but low cost.


What advice would you offer about getting involved in research?

I knew from the start that I wanted to do research - as a medical student I remember saying this in my interview. It's good to keep an open mind. The most important thing is not to close doors. The first step to not closing the door is doing an Intercalated BSc, because if you don't, then trying to get funding to do a PhD in the future is really hard. 

The funders, when you're applying, will look at your track record and whether you've had an interest in research previously, and doing an Intercalated BSc really ticks those boxes. It's a shame it's been removed from the EPM for foundation programme because that's put a lot of students off doing one. I understand there's a cost implication, but that was never the right reason to do one in the first place, to get your EPM score higher. 

If you want to do research, not only does it look good on your CV in the future, but it also teaches you research techniques, gives you an insight into what research means, and enables you to better understand whether or not this is what you want to do. 

For medical students, that's my biggest tip - do an Intercalated BSc, but also seek out opportunities when they arise to get involved in other people's research projects. 

Now, hopefully, the scholarly project in Year 3 at King’s allows people to do this as part of the course. Outside of the course, get involved in other people's research projects, offer to do some of the data collection, and learn how you do the analysis - it's all really good practice.


What advice would you give graduate-entry medical students?

All graduate-entry people have to have a biomedical science degree to come in on the accelerated programme, so they will have a science-based degree. Obviously, you can have a non-science based degree and come in Year 1 in the normal way. 

It helps to have that BSc, and it's difficult to say to people that you have to do another one, but maybe consider doing a Masters. If you want to do science research and your first degree was in history and art, for example, you won't necessarily develop the transferable skills from that degree that would stand you in good stead for doing a basic science or a clinical science PhD. 

You can do a Masters - so it's not just adding another undergraduate degree, it is incremental in building on what you've got previously, but in an area that may be relevant to what you want to do in the future. You do have to balance all these things against a time cost. 

My feeling is medical students are in a great rush to qualify. But actually you’ll realise, once you get towards the end, quite how quickly it's come. In three-or-four years' time after you qualify, and reflect back, would your having taken an extra year made a big difference? Not really.


What career advice can you offer?

Don't stress too much about the decision. Everyone will have some gut feeling about roughly which direction they want to go in. Do they want to be a general practitioner, a surgeon, a physician, or a psychiatrist

Making that high level choice first is all you need to do in the first couple of years after qualification. Take some time, go around the different specialties, learn what they mean and what life in them is like, because once you've made your final decision, that is actually your career for the rest of your life. It is possible to change but when you've gone down the path quite a long way, it's quite difficult to change. 

So it's not just what interests you, but where do these jobs exist around the country, and where do you want to live in ten years' time. If you want to be a nephrologist, renal medicine is a tertiary centre specialty, and most district general hospitals don't have nephrologists. 

If I had wanted to live and work in the rural countryside, it would have been very difficult to be a nephrologist and do that. So you do have to think about your own priorities. 

Finally, choosing your specialty is about what interests you but, as I said before, anything that you start doing in depth becomes interesting when you realise how much there is to learn. I rarely hear about people saying: 'I made the wrong choice’.  So take your time, think about lots of different aspects of what your personal priorities are, but don't be put off by competition. 

Don't say: ‘I'm not going to train to be a cardiologist because it's too competitive', unless you really think you're going to struggle. Try not to be defeatist when making your decision. Go for what you want to do, but take your time to think about what that might be.


What should medical students focus on at medical school to make them stand out?

Don't make choices based purely on your foundation school application because you may end up making choices which aren't the right ones for you. In order to excel, you need to understand yourself what it is that you want to achieve and in whose eyes, because when you move into the world of work, you're moving into a different workplace, a different set of people. Having a good CV is a great place to start when you're applying for things. 

But you can have a great CV that pushes you in one direction - ie, to be a cardiologist - when all along what you're most interested in is neurosurgery, but you've developed things because opportunities arose, and you thought it was good to do them. 

You really do need to think about doing things that are good for you, and are setting you up for what you want to do, rather than for how the world is going to see you. So as far as your foundation programme application goes, then the SJT is the most important influence on your EMP score, for example. 

The SJT is a really good way of testing someone's judgement and professionalism. To do well in your SJT, you need to spend lots of time in the clinical environment, talking to lots of patients and staff, and really developing yourself professionally as an all-round clinician. 

All of these things - like getting involved in other people's research projects - are great things to put on your CV. But don't end up doing a research project that you really don't enjoy because it's not worth it.

Think about what you want to enjoy. Think about, for example: I really want to be a nephrologist - can I find someone to talk to about it? Can I spend a weekend on the renal ward and work out if it is what I want to do? Focus the question back on yourself - what is it that I need to understand in order to make the right choices in the future, because you will pass, and you will get a foundation programme. 

All of these foundation programmes are designed to be good - you move around different places. There is no bad foundation programme. It's really about asking yourself the question: ‘Where do I want to be in five years' time?’ ‘ What are my priorities?’ ‘How do I get there?’ rather than thinking about how other people are viewing you all the time.


What challenges face women wanting to reach the top?

The trajectory of women is different to that of men, and we need to understand why that is. There are more female medical students than there are male - about 55% of medical students are women. And  yet, when you look at the consultant body in the hospital, about 20% of them are women. 

The consultant body obviously reflects where the medical student's body was 20 or 30 years ago, so we need to understand that it's not a reflection of what's happening now. There are obstacles and barriers, but there are also different choices that people make. So not everything is an obstacle or a barrier - some of it is personal choice. 

The obvious one is about having a family, and what choices you make when you have children that you think are right for you and your family. Some women will choose to take a different career path because that's what they think is right for their family. 

I have three children, and I chose to continue on the career path of being a consultant and being an academic because that's what I wanted to do - I felt that it was best for my children for me to do what I wanted to do as well. I've been lucky along the way in having a very supportive partner and being able to get fantastic childcare. 

So I would say to women: don't make assumptions. You can do whatever you want to do - don't let other people tell you what that should be. You don't have to become a consultant or a professor or an academic. But equally, if that's what you've always aspired to, then having children is not a reason to not do that. 

You do have to be organised, and you have to have good conversations with your partner about sharing the roles and responsibilities that come with parenthood. My feeling is that things are changing but - a bit like my advice to medical students - don't listen to what other people are saying. First work out what it is that you want to do, and then there's always a way to make that happen.


What moments have defined you as a clinician and a researcher?

When I first became a consultant, I was balancing my clinical responsibilities with my research, and I was asked whether I wanted to set up a new clinic for patients with sickle cell disease. I knew absolutely nothing about sickle cell disease in the kidney - it was unknown to me and pretty much most other nephrologists in the country at the time. 

It was a request from the haematology department because it was recognised that a number of patients with sickle cell disease were developing kidney failure and that it wasn't really being picked up. Patients weren't being managed very well and there was what we call ‘crash landing’ on to dialysis, where you haven't had a chance to prepare them, they just turn up very unwell and get put on dialysis. 

That's a huge life-changing event for a patient, so you really want to avoid it being an emergency situation - you want to prepare for it. Ideally,  you want to prevent it but if you can't, then you want to prepare for it. 

So I was given the choice whether to take this clinic on or not. I thought about it and it was one of those situations: ‘Do I take on something that I know nothing about when I could just say no?’ I decided to take it on. It was the best decision I ever made because there was a huge unmet need, there wasn't really anyone focusing on these patients nationally, and these are a group of patients who historically have been under-resourced and under-provided for outside of the world of haematology. 

It's a small area and you can learn about it very quickly. So even if you don't know about anything, if you know how to learn - and that's what we're trying to teach at medical school - you can pick up an area very quickly. 

You get to see the patients, and you get to learn with them. I became a national expert in the fields of chronic kidney disease in patients with sickle cell disease, which has been one of the best things I've ever done, and I thoroughly enjoy it. I love the patients and I love the collaboration with other specialties. So saying ‘yes’ to that one question was probably the biggest turning point in my life.


What advice would you give your younger self?

I don't think there's anything I would particularly change. I'm very lucky to be able to say that. But one of the things I've learned over the years is people are always giving out advice, and are always saying to me: 'You must learn how to say no'. 

That's a common piece of advice that women in particular are given: learn how to say no. I actually disagree with that, I think it is ‘learn how to say yes to the things that you want to do’, because it's only by saying ‘yes’ that you get to take on new opportunities. So it's not as simple as saying ‘no’, because sometimes what you end up saying ‘no’ to are the things that would be good to do, but may be difficult. 

You can end up saying ‘yes’ to the things that are quick and easy to do, but aren't particularly of benefit to you. So: learn what to say ‘yes’ to, is my piece of advice to myself and other people. You do have to balance your work-life balance, so you can't say ‘yes’ to everything. But don't have a blanket ‘yes’ or ‘no’ response - really think carefully about it. Sometimes the most difficult things are the things that you have to say ‘yes’ to.


What habits have allowed you to succeed?

I can think of habits I've changed. So my learning style as a medical student was probably similar to other students, in that I was a bit of a ‘last-minute’ person. I would be up the night before, revising for exams. Thankfully, progress tests have removed that pressure now. But I would leave the big exam at the end of the year to the last minute and be up all night. 

That worked to a certain degree. However, once you're in a situation where you have to balance lots of things, particularly when you've got children, you learn that leaving things to the last minute can become overly stressful, and that you rarely do your best when you're doing it at three o'clock in the morning. 

So the habit that I've taken on is being organised, being conscientious, and making sure I have balanced my commitments and my life, but knowing when I'm going to get things done. So being organised. It sounds like a small thing, but it makes such a difference when you're spinning many plates at the same time.


What's your favourite book?

This is the hardest question to answer. I don't have a lot of time to read fiction at the moment, so I'm going back over the years about what I've enjoyed. I like some of the classics - Virginia Wolfe, Thomas Hardy. But the books that I've gone to, to really just turn off and relax, I'm afraid it's got to be Harry Potter. I just love the Harry Potter series - it's something completely distracting and not difficult.

Medspire podcasts are produced by Dr Sanketh Rampes and Dr Anvarjon Mukhammadaminov, both full-time junior doctors. They aim to inspire the next generation of doctors and scientists by exploring the career journeys of leading clinicians and researchers.