Renal Tubular Acidosis, RTA (S3:E4)

It's important information for our primary care providers. I think that's one of the fun parts about allergy. The biggest challenge is making sure you have the correct diagnosis. What is the best outcome or place to send this child? This is Charting Pediatrics from Children's Hospital Colorado, where we examine the latest treatments for the most common complaints in pediatric medicine. And now, your host, Dr. Allison Brent, Pediatric Emergency Medicine Physician at Children's Colorado.

Renal tubular acidosis, or RTA, refers to a group of inherited or acquired disorders characterized by defective renal acid-base regulation. In RTA, the capacity for normal urinary acidification is impaired, either by inability to absorb bicarbonate or excrete ammonia or acid. The result is a net acid retention reflected by a hypercloremic metabolic acidosis with a normal serum anion gap.

In this episode, we will review basic kidney processes that are important for diagnosis and management of RTA in your patients. Welcome to another episode of Charting Pediatrics. I'm your host, Dr. Allison Brent. If you are new with us, I want to welcome you to our pediatric provider community and tell you a little bit about what we do. We are passionate about connecting providers to accessible... clinical education, and new innovations that supports the care of kids.

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Winners will be announced in late September, so please stay tuned. Today, we are so very fortunate to have Dr. Daniel Serrano. very fantastic pediatric nephrologist from Children's Hospital Colorado, join us for today's discussion. Dr. Serrano is an associate professor of pediatrics, bioengineering, and medicine at the University Colorado School of Medicine. Danielle, welcome to the podcast. Thanks, Allison. It's really exciting to be here.

Before we start today's discussion, can you share with our audience a little bit about your background, your medical training, and how you became involved in pediatric nephrology? Sure, I'll try to keep it brief. I studied biomedical engineering at Case Western Reserve University as an undergrad, and I was really just encouraged to apply to medical school by a mentor. And at that point in my life, I...

If I heard a good idea from someone I respected, I just kind of went along with it. So I applied to medical school, got some interviews. When you get into medical school, Kind of turns out, well, do you want to get a job or go to medical school? And I realized I was a good student. So I just kind of landed in medical school. And pretty early on, I was a little frustrated with all the memorization and was pretty turned off. We did biochemistry.

pretty early on. And I was actually really thinking about quitting when luckily they broke us up into small groups for clinical correlation. And I remember exactly the room I was in, exactly the seat I was in when Beth Vogt, pediatric nephrologist at Rainbow Babies and Children's. brought in a, I think he was an eight-year-old pediatric patient on peritoneal dialysis.

We heard all about his story and why he was on dialysis. And he was brought in by his caregiver who did dialysis at home. And I remember distinctly thinking the chances of me being a pediatric nephrologist are slim to nil. But wow, there's something really exciting out there. So I'm going to stick with medical. school so I didn't quit and that first year nephrology physiology was I thought the coolest most exciting block and then

The second year, renal pathology was, again, the coolest, most exciting block. So very early on, my first rotation, I was on pediatrics, and I had one week of elective to start off with. So my very first rotation was pediatric nephrology. And I think by the end of my fourth year of medical school, I'd done about six months of electives in pediatric nephrology. And you may remember me from residency when I trained here, did an equal amount of pediatric nephrology electives.

kind of, for better or for worse, streamlined my career choice pretty early on in nephrology, and there was no doubt that that's what I wanted to do. That's a great story. And I have to tell you, Danielle, that you were one of my favorite residents of all times. You were just so wonderful. I knew you were going to be a superstar. And it was great because you picked up any kid in the ED who might possibly have anything.

Related to nephrology going on with them. So that is good. And it's so wonderful that there's people like you in the world because I really didn't like my nephrology blog. Well, you're being kind. But yes, I certainly do love the kidneys. So I'm delighted. to be here today to talk about them with you. I always think of you as the golden nephron girl or something very similar to that. So welcome. But let's talk about this renal tubular acidosis because

I think that in the community, it may be a bit underappreciated. It's a tough diagnosis for people to think about, understand, categorize, and hopefully you can clarify it for us. But just to start out, what's the prevalence that we see this? Yeah, and that's a great question. So first of all, it's actually quite...

rare. And it depends if you're in pediatrics or an adult, whether it's more inherited or acquired. But often we get a lot of calls on this. Part of it's because of our catchment area, but I'd say our practice gets one or two calls a week. from providers about concern for renal tubular acidosis. And about 80% of the time,

It's usually a low serum bicarb from blood sitting there in the lab and maybe not being processed as quickly. As the red blood cells break apart, lactate is released, and so that surreptitiously drops. the bicarbonate level that's read out. So most of the concern for RTAs, once we repeat the sample and maybe put in the comments, like, please run ASAP, often that.

Kind of, I don't know if it's regression to the mean, but the concern goes away. So it's actually rather rare. And we honestly wonder and are concerned sometimes that it might be overdiagnosed based on that. often we'll see a child in clinic who has already started on sodium bicarbonate supplementation. And, you know, you mentioned in your introduction that it's a...

non-GAAP metabolic acidosis. And so that's usually how I like to frame it and think about it first. So what I always tell the residents is, you know, the sinequinone of diagnosing a acid-base perturbance is knowing what your serum... pH level is. And so if we're really concerned about an RTA, we really need to get a VBG along with that BMP. So the typical scenario is...

Well, someone's worked up a child for failure to thrive. And so as part of that workup, they appropriately get a basic metabolic panel. I think most people get a CBC and a thyroid panel. And usually we get called because... the lab abnormality is the low serum bicarb. And so it's very appropriate to be concerned about RTA. But first, give yourself credit for having also ruled out significant chronic kidney disease, which is also on the differential.

for failure to thrive. So remember to look at that serum creatinine and for any family practice providers or frontline providers. who don't have the pleasure of serving at our tertiary quaternary care centers where most of the normative lab values correct for the patient's age and size, remember that serum creatinine is based on how much muscle you have. So the podcast listeners can appreciate my...

really big guns, but my serum creatinine is about 0.7. I'm an adult female and NFL football players might be like 1.4, but remember to actually eyeball. that serum creatinine and think to yourself the size of that kid. We have estimating equations. They're actually based on height, not weight. But just think, hey, does that...

does that serum creatinine make sense for that kid? You know, a baby's creatinine should need her by about one week or one month in preemies, and she'd get down to about 0.2, 0.3. So... A lot of those lab norms will only flag a high serum creatinine if it's higher than like 1, 1.1, 1.2 for adults. So remember as pediatric providers to look at that serum creatinine.

Having said that, I know the podcast isn't on CKD, but chronic kidney disease. I like that. But give yourself credit in that Failure to Thrive workup that you've just, that patient doesn't have.

end-stage renal disease, which does present often with failure to thrive and is caught sometimes pretty late. So give yourself credit for that. And then moving on to that low serum bicarb, the first thing we usually recommend is first repeat the BMP. with a VBG, right? So on this repeat sample, you send them to lab, order it with comments that say, you know, please draw free-flowing venipuncture to, you know, try to mitigate any hemolysis.

and then also get the VBG at the same time, and that also needs to be run fairly. quickly. We don't want that sitting around. If it isn't going to sit around, it should be on ice. So it needs to be processed a certain way. And the lab will be able to handle that, but get them both at the same time. And then if you want bonus at the same time, you know, this is a toddler. So often I'll give the parents

a urine bag as they're going to lab. And so the bag is placed, this doesn't have to be a sterile urine sample, but that way during the course of the couple hours of getting to lab, getting checked in, crying through the blood stick. Usually the patient will also make urine. And then you have your urine studies drawn at the same time as the BMP and the VBG. And so I don't always really need the UA, to be honest. It's nice to see the pH.

If you look in the textbooks that, man, the RTA is awful to read about. It's just awful. It gets complicated, but they'll talk about urine and anion gaps. I've only done that once. I really don't get to that. very often at all. But that way you have the urine sample there and it's not, it's like one less trip to lab. So that's usually the way I roll. But the first step here is to look at the serum pH. And if it's an RTA, you have to be acidotic, right? And so often what...

usually happens is that on the repeat blood tests, when they're processed quickly, everything's normal, which is great, right? I mean, your child still has failure to thrive, but at least they don't have RTA. The second thing that I've found is that it can be a respiratory alkalosis with metabolic compensation. You can give that kid all the bicarb supplementation in the world. Their kidneys are going to be super smart like they are and continue to pee out the bicarb.

And so you don't want to throw meds at a kid, especially a sour tasting medication. to a toddler that they have to take three or four times a day. It's just no fun and it doesn't really help with family dynamics or feeding time. So we want to be thoughtful before we prescribe that. So that's usually why I step back.

get the BMP, the VBG, and actually make sure we have a metabolic acidosis. There should be some respiratory compensation. And then most of the time that's gotten rid of a lot of concern for the RTA. Any questions on that so far?

So in thinking about the view from the referring provider, how do they usually present? You mentioned failure to thrive. I know on the other extreme, I see the kids, you know, vomiting, diarrhea, very sick in the ED.

what's the middle ground where they might come to their PCP where it would trigger, hey, could this possibly be RTA? I think really the main presenting factor is usually failure to thrive. Now, some of the more acquired... or inherited if we're going to get away from RTA and think more significant kind of.

tubular wasting or tubulopathy, you've got Fanconi syndrome. And that's when your proximal tubule, which is like the intern of the nephron that does the bulk of the reabsorption, most of the work, it's like that is just not working very well. So imagine you're on inpatient service and all your interns don't show up.

That's what like proximal tubulopathy is. And so Fanconi syndrome is really significant. These kids often need G-tubes. I mean, there's profound failure to thrive. They present pretty early and they can be pretty sick. Cystinosis is the most common cause. We can certainly...

as Doug Jones would call it, iatrogenesis imperfecta. Some of the chemotherapeutic drugs like ifosfamide can cause an acquired proximal tubule dysfunction. And then you have more rare inherited disorders like the more distal tubulopathies like Barters and Gittleman's. They usually present with a metabolic alkalosis because it looks like you're on diuretics. It's like a...

It's like an inherited diuretic that's always on. Barter syndrome is like you're on a loop diuretic and Gittleman's is like you're on a thiazide. And most of those barters presents in the neonatal period, whereas Gittleman's will present. Often, incidentally, someone will just notice they have a really low serum potassium and they get worked up. How about kids who are on drugs like... lithium or amphotericin, should they be screened at some point or regularly for a possible RTA?

That's an interesting question. I'd be interested to, I need to look at the literature to see what they're recommending for that. We certainly see it, but it's usually once someone has thought to look for it. Often if they're making a lot of urine or all of a sudden they're having secondary anuresis, et cetera, we do want to worry about a tubulopathy. I remember one of the nephrologists I worked with,

thought that everyone on lithium should get a screening renal ultrasound, I think once a year. I'm not sure the cost benefit, you know, analysis on that. And certainly we get ascertainment bias on some of these referrals that we get where we're convinced that everyone on lithium.

has such a thing that it might be quite rare. So, I'm not, I think I have some mass retirement bias and might not be the best person to answer that without reviewing the literature. Okay. And then on the other extreme, can you talk a little bit about the kids who present?

really severely. And again, PCP might see them in their office. I see them in the ER, but they're, you know, they're acidotic, they're vomiting, their diarrhea, their dehydration. The beginning, we don't know, is it sepsis or, you know, what's going on here? How often do you see that kind of a... florid presentation.

I've actually never seen that as the primary RTA issue. Now, someone could have an underlying RTA and then have decreased threshold for, you know, when they get sick, they really get tipped over. But that's not usually how I see them present. And certainly some of our...

Like our cystinotic patients, our kids with Fanconi syndrome, if they get a diarrheal illness and they already have urinary losses, they can get really sick real fast, certainly. It's not usually their presentation. Okay. So when we think about what the most common... causes or triggers would be. We know failure to thrive, possibly medications or a combination of a viral trigger on top of an underlying disease process.

Sure. And then there are also children who distal RTAs are more common to be inherited. But as we go through the RTAs, so first of all, stepping back, I know people kind of... grown as soon as I mentioned it, but my code name in residency was nephron. So I always visualize a nephron when I think about RTAs and then we kind of need to pick, do we, it's really annoying in that.

RTAs were numbered in the order in which they were described rather than the order in which urine flows through the nephron. I usually like to mentally take a magic school bus tour through the nephron though. So I imagine urine going from the glomerulus, the proximal tubule, to the loop of Henle, to the distal convoluted tubule, and the collecting duct. So I usually describe RTAs and think about them in that order.

So that would make us start, though, with the proximal type 2 RTA. This is, again, the proximal tubules. You know, if we think about our filtered load, 20% of our cardiac output goes straight to our kidneys. As a very nephrocentric person, I like that. And then 20% of that actually gets filtered across the glomerular basement membrane and made into urine. As an adult, that's 180 liters of urine that we make per day.

Obviously, we don't void 180 liters of urine per day. Our nephron reabsorbs the bulk of that, like 98%, 99%. And we only void one to three liters per day, depending on how much we take in and our excess fluid. If you think about all that filtered load and all that sodium bicarb that gets just freely filtered across the glomerular basement membrane, the proximal tubular is in charge of reabsorbing most of it, 95%. And so when we think of a proximal RTA...

that set point for reabsorption is just a little bit lower than it's supposed to be. So maybe you only reabsorb 92% of the filtered load. That's still a lot of sodium bicarb. So these kids need boatloads of bicarb supplementation. The good news is they only need it usually for a short period of time because it's just an immaturity of the proximal tubule. So if we went around and got basic metabolic panels on like a bunch of two-year-olds.

a bunch of term babies, and a bunch of premature babies, you would notice the pattern, right? The two-year-old should have a normal bicarb because their tubules are fully mature. Term babies, their bicarbs are in like maybe the high teens. And then preemies, they're like their bicarbs 12 to 16, much lower. And it's just because that proximal tubule hasn't.

learned or hasn't increased its set point appropriately yet. So a proximal RTA is really just a prolonged immaturity of that nephron and they usually grow out of it. And so the good news about having a proximal RTA is that It's usually temporary. The bad news is these kids need sometimes like 20 millequivalents per kilo of sodium bicarb to overcome the bicarb they're peeing out. So that's the proximal.

The distal RTA is much less common. So proximal RTA is more like 90% of cases. Distal RTA is like 10% of cases. So if you're taking your board exam... remember first, make sure it's a metabolic acidosis. Two, make sure it's a non-GAAP metabolic acidosis. And then once you've gotten to that point, you know, well, you're either...

peeing out your bicarb or you're pooping out your bicarb. So if the patient doesn't have diarrhea and they have a non-gap metabolic acidosis, then yes, like it's time to think about an RTA. And by then on your board exam, just pick proximal because that's going to be 90% of cases.

I like that logic. It usually holds true. And then the distal convoluted to the type one or distal RTA, this was described first, but it's less common. And this is when you can't acidify your urine. So some clues to this is that first. of all it's

often inherited. So you want to think about family history. Sometimes it's associated with deafness or hearing loss. So if you're worried about this, those kids can get a hearing screen. And then as part of my evaluation, I always check renal anatomy on patients that I'm... evaluate and make sure you have two kidneys that, you know, they're reniform in the right spot. There's no hydronephrosis. And so distal RTAs are associated with nephro.

calcinosis and a high urine calcium to creatinine ratio. So getting an ultrasound can also point you in the right direction. The good news about having a distal RTA is that you really only have to buffer. This is where hydrogen secretion occurs. And so if you can't acidify your urine, you'll have an alkaline urine.

We only have to get rid of about one millequivalent per kilo of hydrogen ions into your urine per day. So that's a much lower dose of bicarb supplementation that these kids need. The bad news is it's fixed and it doesn't go away. So it can be a philosophical question as to which RTA you would rather deal with. And then type 3 is more historical. It's a combination of type 1 and 2. And so you think it's a proximal and they outgrow most of the dose, but they're still with a fixed.

defect. And so then they've just kind of outgrown their proximal and they still have their distal. I think I followed one kid like that in residency with Gary Lum. Like I've never seen it since. And then type four is really where you think about that hyperkalemic. And this is their collecting ducts.

We often see it most commonly in pediatrics. So if we think about the collecting docs, collecting docs are like the attendings of the nephron. They only do two things. Just like I as an attending now only do two things. I bill and I co-sign the residence notes. the collecting ducts respond to aldosterone and ADH. And so aldosterone is really the important part here. If you remember aldosterone, you reabsorb sodium in exchange for potassium and hydrogen secretion. And so...

We see a type 4 RTA quite commonly in kids with bad pyelonephritis. As it's more of an ascending issue, the collecting ducts can be a little kerfuffled, and you can get a pseudo-hypoaldosteronism. You have Aldo on board, but the collecting ducks don't respond as well. And so those kids can look pretty sick and they can have a pretty significant...

hyperkalemic metabolic acidosis during their pylo. This is usually in the neonatal period or infancy. And they also, you know, as infants have impaired response and potassium secretion capability because their tubules are still developing. So those kids, you know, give bicarb supplementation to help with manage the hyperkalemia and then treat their pylo and it should go away. So is one of the tip-offs for the type 4 that that's the one group that has the hyperkalemia?

Yeah, that's usually a flag that yes. And often, I haven't seen it in my practice, at least outside of the setting of pylo. I think pylo nephritis, I think in adults, they can see it quite a bit in DKA as well.

Well, I love that explanation, Danielle. I think that as this is just about, you know, the 50th anniversary of Woodstock, it is great to be driving the bus through the kidney and the nephrons and the proximal distal tubules to the collecting system. Well, welcome to my world. I view the world. Man, maybe I would have been better at this had I thought about it in a different way. It's never too late to do a nephrology fellowship. I am this close to recruiting Jim Todd. No way.

Jim Todd disagrees, but I think I've been working on him for a few years, so you could be his co-fellow, theoretically. All right. Well, when I retire, I know that I have a new fellowship that I can go to. Well, when I was coming up, I was told I needed a pulse and an interest to be a nephrologist, and then I was correct. and said, well, actually all he needs is a pulse. I thought that was an ER doctor. That's all we needed for them.

Oh my gosh. So this is a wonderful explanation. And I hope that all of our listeners out there really get this drive through on the golden bus and the three different types that you're really going to see because you explained it so beautifully. But how should the referring providers then approach management? Is it in collaboration with you? Is it a phone call? Do they need to come here? Or can they just kind of figure it out based on where they are on their bus trip?

Well, I'm biased. I think any child with a tubulopathy... merits a nephrologist, at least an initial evaluation. But I do recognize, especially with the large area that we serve, that that isn't always possible and that sometimes it's a great hardship for the family to come to main campus.

Hopefully with the advent of telemedicine, we'll become ever more available. However, certainly, please, please, please call us. And we're happy to do a lot of the management on the phone. I mean, as a nephrologist, honestly. It's very data-driven, so with excellent partners in front of the patient and telling us their volume status and how the child looks.

We can do most of our job with a set of labs from afar and we can definitely help co-manage. I think it would definitely be helpful to have that phone call to like maybe. We can potentially pick up some nuances and think about some things since we see this a lot. So yes, I think any child with a tubulopathy warrants a phone call at least to nephrology. And then we love seeing these kids in clinic. And certainly it's a shifting.

target. This is why I'm a pediatric nephrologist, not an adult nephrologist. Their tubules are developing. So you really reach your adult normative kidney function by about 19 months of age. So what's normal for preemie versus a term baby versus six month old is totally different.

And this is what we geek out about. And this is totally our jam. So we can very least help manage. Those proximal RTAs, like I said, are going to require a huge dose of bicarb supplementation. We really do want it dosed. three or four times a day because they're constantly filtering and constantly losing it in their urine.

Usually what you'll see is those kids will start to have a growth spurt once they're on an appropriate dose, and then they'll kind of outgrow that dose, and you can kind of taper it away, whereas the distal convoluted tubule, that type 1 distal RTA. That's just fixed. And then you'll have to dose adjust with time. Are they on that for life then? Yeah. Oh, gosh. You really, I mean, Pete Marani taught me as a resident, you know.

pH balance is the number one job of your body. It's more important than heart rate, than blood pressure, than temperature, than all those other vitals. If we think about the billions of chemical reactions that are happening, they're highly pH sensitive. And so RTAs are...

Really important to treat. We just don't want them acidotic because that's when they get rickets, especially during their growth parameters, during their growth spurts. We want their bones to be healthy. And if they're acidotic, that won't occur. And the rest of their body won't function quite as well. Right.

So I tell the residents all the time, kids are like chia pets, you need salt and water to grow. So if your tubules aren't tubulating very well and you're losing stuff in your urine that you need, that's important for a growing child and you really only get one shot. Absolutely.

How should our referring providers talk to families about this, the diagnosis, the follow-up expectations? Yeah, I think it's important for the primary care providers to... kind of frame it in the way that like, hey, you know, often this is a spurious lab value just from the way it was processed. So first, you know, our first step is to really make sure that we're dealing with what we think we're dealing with. So, you know, sorry for the second.

blood draw, but while we're doing this, we'll just cover all our bases. We'll put on the urine bag. We'll get the two additional, we'll get the VBG and the BMP. And based on that, we'll have a lot more information as to whether you even need referral. And then once there is...

is a referral, you know, I think just framing it like, well, hey, this could actually really help your child grow if this is what he or she has. And often it's temporary. And so kind of putting it in that framework can be helpful. And then talk a little bit about prognosis. You mentioned that some kids grow out of it, but what's the overall outlook? I think the proximal RTAs, it's a nuisance for sure because it's...

you know, thrice daily sour medication for your toddler, which is, I don't think anyone would willingly sign up for, but overall they do well and then they grow out of it. So it's fine and it's not typically inherited. you know, of all the things to be diagnosed with, that's, it's not convenient, but it's also not the worst. And then the distal RTA, it's very, very rare. So I wouldn't have, if you're...

pregnant right now with a child, I wouldn't stay up at night pondering the chances of you carrying a child with a distal RTA. It's very rare, unless, of course, you have a family history. Then it might not be so rare for you, and it's worth pondering. But I wouldn't lose... too much sleep over the RTAs. That's one thing that we can actually help with and help.

treat and manage versus Fanconi syndrome. Like that's a whole nother ball of wax. Our patients with cystinosis end up, you have to have a healthy tubule to have a healthy glomerulus and you have to have a healthy glomerulus to have a healthy tubule. So all of these renal diseases.

If you have a bad enough tubulopathy, you do end up with renal failure and you need a kidney transplant. And so those kids do go on to transplantation. But that is not at all your typical renal tubular acidosis. That's a very small.

piece of the pie. Wow. And what's new on the horizon for either diagnosis or treatment? And in your bioengineering lab, can you come up with like a little ODT of bicarb for these kids? Well, you know, it comes down to the number one rule of medicine, which is if something's low, you give them more. And if something's high, you give them less. The caveat is that rule does not apply to sodium. Sodium's backwards.

But yeah, right now we just give everyone bicarb. And this is one of the, if you go back more to like Dickinsonian novels, you know, there it's. hypothesize that maybe Tiny Tim had an RTA because, you know, one of the few things, you know, at the end Scrooge helps with his medications and he was feeling better. One of the few things that they could do back then was give.

Bicarb and baking soda. Baking soda, I was going to say. Yeah, to people. Yeah, so I don't know if there's any cutting edge research on this because people can take bicarb. So if Tiny Tim had had more bicarb from Scrooge earlier in life, he might not have been Tiny Tim. Right. No, he probably wouldn't have had rickets. Yeah. Gosh. I know. That is a great breakthrough. I love it.

I don't know if we can posthumously diagnose fictional characters, but we can try. They would never know. There you go. What's important for the PCPs to know in terms of ongoing follow-up for these patients? Sure. I think it depends on... Once we confirm the diagnosis, typically we'll check labs since they're growing children. We want to make sure that we dose adjust. Either the proximal RTAs, they often need dose adjustments quickly until they're tubules.

are more mature and they start to catch up, then that's when they start to outgrow their dose. And then we can even back off. But usually those kids will check labs like every four months or so. And again, those kids don't have to necessarily come to our clinic or come to our main location.

we'll often get labs locally and we can just titrate their medications over the phone or in partnership with their primary care provider. So there can be a lot of work done over the phone once we actually make the right diagnosis. So yeah, I'd say every four months or so, just that's typically what I do with all my kids with tubiopathies. Perfect.

Well, Danielle, it has been such a treat to have you on this podcast, and you really have enlightened all the world about renal tubular acidosis, which is quite a feat, I must say. But in closing, I like to ask this question of all of our guests. But what do you find the most satisfying about your job? I love that I get to live in that bubble. And I think we've all had that bubble of...

like the epiphany of nephrology and physiology, where at first the kidneys seem super duper complicated and they just want to make you groan. And then this light bulb goes off and all of a sudden you get it. I'm feeling thirsty because my serum osmolality is a little high. My ADH is going to kick up. I'm going to make a small amount of very concentrated urine and I'm going to drink a lot to compensate. You just go through life.

for a good couple of weeks as a medical student, understanding physiology. And I love that I get to live in that bubble. every single day. And that is, now I don't know how to intubate a child. I don't know how to save lives like you do, but I just, I love the physiology and I love the data and I love being able to fix. the numbers and help children feel better. And there's nothing as satisfying as going into the ICU.

and dialyzing a previously healthy child who has acute kidney injury and then their kidneys recover. And it is just the most amazing thing ever. So I think acute care and critical care nephrology and just the physiology of it, I just love it. That's wonderful. We're so lucky to have you and all of us all over the world. Thank you for this great podcast. Thanks, Allison. Thanks to all of you for listening to this wonderful podcast. And until next time, keep on keeping kids safe out there.

If you have more questions on this topic or a suggestion for a future podcast topic, write to chartingpediatrics at childrenscolorado.org. If you like this podcast, please rate us and share with others who might be interested. This is a production of Children's Hospital Colorado.