SuPAR (soluble urokinase-type plasminogen activator receptor) has been shown to be a promising biomarker in its ability to predict the development of chronic kidney disease in adults years earlier than traditional risk factors.
Darcy Weidemann, MD, pediatric nephrologist at Children’s Mercy is leading the largest North American study ever conducted to look at whether suPAR may be helpful to predict kidney function decline in children.
Listen in to Darcy Weidemann, MD as she explains the potential role that monitoring suPAR levels may play in improving the care of children with chronic kidney disease.
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SuPAR and Chronic Kidney Disease: Identifying Biomarkers for Disease Progression
Featured Speaker:
Learn more about Darcy K. Weidemann, MD
Darcy K. Weidemann, MD
Darcy K. Weidemann, MD specialties include Chronic kidney disease and Environmental Nephrotoxicology.Learn more about Darcy K. Weidemann, MD
Transcription:
SuPAR and Chronic Kidney Disease: Identifying Biomarkers for Disease Progression
Dr. Michael Smith (Host): So, our topic today is identifying biomarkers for kidney disease. My guest is Dr. Darcy Weidemann. She’s a pediatric nephrologist at Children’s Mercy Kansas City. Dr. Weidemann, welcome to the show.
Dr. Darcy Weidemann (Guest): Hi. Good morning.
Dr. Smith: So, let’s just kind of like a review, first. Tell us a little bit about the prevalence of chronic kidney disease in children and what are the main causes?
Dr. Weidemann: Sure. Yes, so, chronic kidney disease is actually, fortunately for pediatrics, much less of a problem in young children compared to adults but it’s important just to have a framework that chronic kidney disease in adults is a huge problem. It’s about 14% of the United States population that has chronic kidney disease. It’s a very extensive problem and actually costs about 7% of the entire Medicare budget, almost $31 billion dollars.
Dr. Smith: Wow!
Dr. Weidemann: Yes, it’s a huge deal for the government and also for our patients. You know, in children, it’s a little different. Fortunately, children comprise a minority of this population, probably a few thousand children with end-stage renal disease, although a much higher proportion who have chronic kidney disease. What’s interesting in children is the etiologies are a little bit different. Within 50-60% of children with chronic kidney disease are due to underlying congenital abnormalities of the kidney and urinary tract--so, congenital problems that they’re born with. This is in stark contrast to, in the adult population where diabetes and high blood pressure account for the vast majority of chronic kidney disease in adults.
Dr. Smith: So, we know that in the adult population, there are different biomarkers and one that really has been shown to be quite a reliable predictor of disease progression is called SuPAR. But now, your group and Children’s Mercy is interested in this same biomarker in children. Tell us a little bit about what the SuPAR biomarker is.
Dr. Weidemann: Sure. I guess the one important thing to note is that the state of research with biomarkers and chronic kidney disease is really that we have a lot of work to go. Right now, traditional biomarkers typically are high protein in the urine or proteinuria and high blood pressure. They are sort of the two most important risk factors that we know we currently use for prediction of chronic kidney disease progression and eventual need for kidney dialysis or kidney transplant. The important thing for children is that we know that these are important biomarkers or the thought is that there may be much better ones out there, you know? Like I mentioned, more than half of our children have underlying problems, congenital problems, and many of these children do not have proteinuria or high blood pressure as part of their disease process. So, really, there’s been a lot of interest in developing biomarkers, particularly in pediatrics, for children that may not have evidence of the traditional risk factors but still have that same risk for progression to end-stage renal disease, ultimately. So, SuPAR is one of the new biomarkers out there that’s caused a lot of interest in the field in the last year or two and it’s a simple protein that’s expressed in a lot of different cells in your body but it’s also expressed in the kidney and, in particular, the podocytes, which is part of the important filtration barrier in the kidney. It’s a simple protein that we can measure in just a few hours in the blood that has been shown in adult populations to actually be much more predictive of adults’ development of chronic kidney disease over a period of several years.
Dr. Smith: It’s considered an earlier biomarker, correct? I mean, there’s the traditional biomarkers that you can look at, but this is something that, at least in the adult population, can give you some information earlier, before the progression gets really bad. Is that kind of the same thought process in the kids?
Dr. Weidemann: Well, that’s certainly one of the hopes, yes. Absolutely. And, the hope. In the adult population, SuPAR was able to predict the onset of chronic kidney disease in adults actually much sooner and a better stratification tool than our traditional risk factors which are high blood pressure and proteinuria.
Dr. Smith: So, I know Children’s Mercy and I know you’re involved with this in actually doing the research on SuPAR, some of it. Tell us a little bit about what’s going on there.
Dr. Weidemann: We are going to be using the CKiD study which stands for “Chronic Kidney Disease in Children” and this is actually the country’s largest prospective cohort of children with chronic kidney disease. We have now, I think, over 900 children enrolled in the study and we’ve been following many of them, actually, for more than a decade over time with this particular study. So, our goal with the SuPAR project is that we are going to be examining the SuPAR levels in these children with chronic kidney disease and we have two particular questions. The first question is whether the sort of baseline SuPAR levels—so, when the patients get enrolled in the study, can we use SuPAR to predict what happens to their chronic kidney disease over time? Then, the second question we’re going to be looking at is whether a change in SuPAR—so if somebody’s SuPAR rate is going up quicker over time, does that predict their risk for needing a kidney transplant or kidney dialysis down the road better than our traditional risk factors?
Dr. Smith: So, I guess, where are you at in all of this research at this point? Is this just at kind of the beginning stages? When do you plan on having maybe some results from all of this?
Dr. Weidemann: Yes, so we received a grant from the Marion Merrell Dow foundation to support this research. Dr. Srivastava and the nephrology research lab here at Children’s Mercy will be actually performing the research for us and actually doing the test on the participants. We’re hoping to have some preliminary results within the next few months.
Dr. Smith: So, just to kind of summarize it all, Dr. Weidemann, so we have a potential biomarker that could predict progression of chronic kidney disease, maybe an earlier marker that also will be used to follow the progression of treatment as well. We would like to see the SuPAR level come down, obviously, if we’re treating appropriately. So, this is really exciting work and I wish you the best of luck with the research that you’re doing and thanks for coming on the show. You’re listening to Transformational Pediatrics with Children’s Mercy Kansas City. For more information, you can go to www.childrensmercy.org. That’s www.childrensmercy.org. I’m Dr. Mike Smith. Thanks for listening.
SuPAR and Chronic Kidney Disease: Identifying Biomarkers for Disease Progression
Dr. Michael Smith (Host): So, our topic today is identifying biomarkers for kidney disease. My guest is Dr. Darcy Weidemann. She’s a pediatric nephrologist at Children’s Mercy Kansas City. Dr. Weidemann, welcome to the show.
Dr. Darcy Weidemann (Guest): Hi. Good morning.
Dr. Smith: So, let’s just kind of like a review, first. Tell us a little bit about the prevalence of chronic kidney disease in children and what are the main causes?
Dr. Weidemann: Sure. Yes, so, chronic kidney disease is actually, fortunately for pediatrics, much less of a problem in young children compared to adults but it’s important just to have a framework that chronic kidney disease in adults is a huge problem. It’s about 14% of the United States population that has chronic kidney disease. It’s a very extensive problem and actually costs about 7% of the entire Medicare budget, almost $31 billion dollars.
Dr. Smith: Wow!
Dr. Weidemann: Yes, it’s a huge deal for the government and also for our patients. You know, in children, it’s a little different. Fortunately, children comprise a minority of this population, probably a few thousand children with end-stage renal disease, although a much higher proportion who have chronic kidney disease. What’s interesting in children is the etiologies are a little bit different. Within 50-60% of children with chronic kidney disease are due to underlying congenital abnormalities of the kidney and urinary tract--so, congenital problems that they’re born with. This is in stark contrast to, in the adult population where diabetes and high blood pressure account for the vast majority of chronic kidney disease in adults.
Dr. Smith: So, we know that in the adult population, there are different biomarkers and one that really has been shown to be quite a reliable predictor of disease progression is called SuPAR. But now, your group and Children’s Mercy is interested in this same biomarker in children. Tell us a little bit about what the SuPAR biomarker is.
Dr. Weidemann: Sure. I guess the one important thing to note is that the state of research with biomarkers and chronic kidney disease is really that we have a lot of work to go. Right now, traditional biomarkers typically are high protein in the urine or proteinuria and high blood pressure. They are sort of the two most important risk factors that we know we currently use for prediction of chronic kidney disease progression and eventual need for kidney dialysis or kidney transplant. The important thing for children is that we know that these are important biomarkers or the thought is that there may be much better ones out there, you know? Like I mentioned, more than half of our children have underlying problems, congenital problems, and many of these children do not have proteinuria or high blood pressure as part of their disease process. So, really, there’s been a lot of interest in developing biomarkers, particularly in pediatrics, for children that may not have evidence of the traditional risk factors but still have that same risk for progression to end-stage renal disease, ultimately. So, SuPAR is one of the new biomarkers out there that’s caused a lot of interest in the field in the last year or two and it’s a simple protein that’s expressed in a lot of different cells in your body but it’s also expressed in the kidney and, in particular, the podocytes, which is part of the important filtration barrier in the kidney. It’s a simple protein that we can measure in just a few hours in the blood that has been shown in adult populations to actually be much more predictive of adults’ development of chronic kidney disease over a period of several years.
Dr. Smith: It’s considered an earlier biomarker, correct? I mean, there’s the traditional biomarkers that you can look at, but this is something that, at least in the adult population, can give you some information earlier, before the progression gets really bad. Is that kind of the same thought process in the kids?
Dr. Weidemann: Well, that’s certainly one of the hopes, yes. Absolutely. And, the hope. In the adult population, SuPAR was able to predict the onset of chronic kidney disease in adults actually much sooner and a better stratification tool than our traditional risk factors which are high blood pressure and proteinuria.
Dr. Smith: So, I know Children’s Mercy and I know you’re involved with this in actually doing the research on SuPAR, some of it. Tell us a little bit about what’s going on there.
Dr. Weidemann: We are going to be using the CKiD study which stands for “Chronic Kidney Disease in Children” and this is actually the country’s largest prospective cohort of children with chronic kidney disease. We have now, I think, over 900 children enrolled in the study and we’ve been following many of them, actually, for more than a decade over time with this particular study. So, our goal with the SuPAR project is that we are going to be examining the SuPAR levels in these children with chronic kidney disease and we have two particular questions. The first question is whether the sort of baseline SuPAR levels—so, when the patients get enrolled in the study, can we use SuPAR to predict what happens to their chronic kidney disease over time? Then, the second question we’re going to be looking at is whether a change in SuPAR—so if somebody’s SuPAR rate is going up quicker over time, does that predict their risk for needing a kidney transplant or kidney dialysis down the road better than our traditional risk factors?
Dr. Smith: So, I guess, where are you at in all of this research at this point? Is this just at kind of the beginning stages? When do you plan on having maybe some results from all of this?
Dr. Weidemann: Yes, so we received a grant from the Marion Merrell Dow foundation to support this research. Dr. Srivastava and the nephrology research lab here at Children’s Mercy will be actually performing the research for us and actually doing the test on the participants. We’re hoping to have some preliminary results within the next few months.
Dr. Smith: So, just to kind of summarize it all, Dr. Weidemann, so we have a potential biomarker that could predict progression of chronic kidney disease, maybe an earlier marker that also will be used to follow the progression of treatment as well. We would like to see the SuPAR level come down, obviously, if we’re treating appropriately. So, this is really exciting work and I wish you the best of luck with the research that you’re doing and thanks for coming on the show. You’re listening to Transformational Pediatrics with Children’s Mercy Kansas City. For more information, you can go to www.childrensmercy.org. That’s www.childrensmercy.org. I’m Dr. Mike Smith. Thanks for listening.