Chapters Transcript Prenatally Identified Renal Abnormalities-Evaluation and Management Dr. Coplen discusses the evaluation and managment of prenatally identified renal abnormalities. I wish I had something to disclose, but I don't. So, uh, this is just a laundry list of abnormalities that can be identified during pregnancy, and most commonly urinary tract abnormalities are the things that are identified about 1% of boys and 0.5% of females, you would identify some abnormality during pregnancy. Most of it's gonna be benign physiologic dilation and not significant pathology, uh, that's ever gonna require any significant intervention. Uh, kidney starts forming very early on, uh, in pregnancy, uh, between 5 and 6 weeks, and, uh, there's a bud that comes off of the wolffian duct that meets the, uh, metanephric mesenchyme to, to form the kidney, and. If there's some perturbation of that, if the, if the bud doesn't meet this mesenchy normally, or the bud doesn't recantalize or something like that, then uh you get, you know, hypoplasia, dysplasia, or perhaps even agenesis of the kidney. And so, the generic term is congenital anomalies of the kidneys and urinary tract, and again it's typically gonna be some genetic dysregulation of the ureteral budding, although if you look at it, there's, you know, well over 25 or 30 genes are involved in uh renal and uh kidney development. Common ones would be the Wilms tumor gene and. Uh, things like that, but there are multiple other genes that are involved in kidney development, and about 1 in 600 births have some abnormality that I guess is clinically significant, being about 1 in 100 have, uh, this identified. I have to say when I came up with this talk, uh. With Angela, I think in May or whatever, I didn't realize that uh this paper was going to be released in pediatrics in July, so I decided I'm going to spend some of my time going over this publication that was published, uh, I guess now, you know, 2.5 months ago, and basically it's uh. Compilation of the section on urology, nephrology, radiology, and hospital medicine trying to determine, you know, to describe what goes on, uh, what is identified during pregnancy, you know, how it should be managed during pregnancy, and then what are the, uh, I guess recommendations to the best of our ability of how they should be evaluated and how long they should be evaluated, uh, postnatally. So again, you're gonna have the most common is gonna be non-obstructive abnormalities, which is gonna be transient physiologic dilation of the kidney, or perhaps reflux, uh, less commonly obstruction of the level of the kidney with the UPJ or obstruction of the level of bladder from a mega ureter, or uh if you have a duplicated system with uh a urethrocele and ectopic ureter, and then, uh, more significant. Uh, neuropathies that require, you know, intervention occasionally during pregnancy, but certainly relatively, uh, urgently, uh, postnatally would be obstruction, urethral obstruction, posturethral valves or urethral atresia. So this is the uh fetal urology grading system that's most commonly used during pregnancy, although we'll talk about a different system, the UTD system uh that is also uh gaining uh. Uh, more widespread utilization, and uh I think you'll probably see it in reports from Children's Hospital radiologists, but also from some of the radiologists around uh the Midwest, as they've uh uh transitioned to using this as more uniform uh. Descriptive technique. And so ultrasounds, you're gonna look at, you know, the parenchyma. So down here in the left corner is a picture of a right kidney, and the right kidney should typically be the same or less bright than the liver that it's adjacent to. So this kidney doesn't look super dilated. There's a little bit of kosis, but there's something abnormal in that the tissue is echogenic. So, again, you're gonna look at the parenchyma. Is it thin? Is it echogenic? You're also gonna look to see if there's hydronephrosis. So the middle one here is a transverse view of the kidney. Kidney and there's very minimal dilation in the kidney. The parenchyma itself looks pretty normal, but this is probably an extra renal pelvis. So, uh, when they're, when we talk about measuring AP diameter in these uh in these assessments, you're taking a transverse measurement of the kidney, and then measuring the AP diameter of the renal pelvis, uh, to assess, uh, you know, risk for obstruction. And I'll just tell you, if the, if the renal pelvis is dilated. But there's not much dilation inside the kidney, it's much less like there's obstruction. And then at the bladder, then we're looking to see is the bladder thick, uh, is the bladder overdistended. This is a patient who's actually got a dilated distal ureter here, so, again, you're gonna assess to see if there's a dilated distal ureter. So the SVU gra SFU grading system is one is basically normal. So here's a kidney which is very minimal dilation. Uh, and that's almost certainly a normal variant, could indicate reflux, and we'll talk a bit a little bit later about who do we decide to evaluate for reflux and who do we don't, who we don't, who we don't do that. Uh, grade 2 and 3 are progressing more dilation, so, uh, 2 again is clearly not obstruction, just based on looking at it, uh, and, uh, doesn't again give us much information about reflux, but 3 and 4 are more likely to be obstructed. So in 3, the KOCs are diffusely dilated, but the renum is. Normal appearance and then 4, it's gonna be, you know, very dilated with thinning of the renchyma so an SFU grade 4, probably at least 50% of those turn out to have clinic significant obstruction that at some point we would decide to uh proceed with intervention. So, the prenatally, the risk stratification has to do predominantly based upon the AP diameter. So, if you go down here in the left corner, if you have a low-risk patient it's gonna be less than 7 millimeters at 28 weeks of pregnancy, and at greater than 7 to 10 millimeters at greater than 28 weeks of pregnancy, and just again with a little bit of. Central dilation is normal. So like on this here, this is a transverse view. There's just pretty minimal central dilation and and it's a little bit skewed, but this is probably an a one. But on the left side you can see there's dilation here, but there's also dilation of the inside KOC. So this would probably be an increased risk and something that we'd wanna be followed. And uh stratification is based mostly upon the uh the most severe abnormality. So in this case here, obviously a markedly this is a markedly extended bladder and then uh the kidneys here. So this is a patient here with significantly increased risk that's gonna be followed, you know, pretty closely during pregnancy. Now the recommendation is every 4 weeks. Until delivery, and that's not a decision that you as pediatricians make. Personally, I think it's probably a little bit frequent for most of these things, uh, but I think that's certainly the recommendation so that in case it progresses, I guess, uh, a site site delivery, a timing delivery could be changed, but it's actually pretty rare that we have to change the timing or site of delivery based upon the prenatal findings. And so then, you know, the suggested postnatal evaluation manners is based upon the antenatal ultrasound. So, for example, on this one up on the top here, this is a uh dilated kidney with some caliectasis, so it's gonna be an increased risk uh on this one here. Left kidney has a dilated ureter, so that's gonna be increased risk. Uh, the right kidney in and of itself isn't, uh, too concerning to me as a urologist, uh, but the the evaluation is gonna be directed by this, and so, uh, with kids, you know, historically we got imaging maybe at, you know, 4 or 5 days of age, but now, you know, kids are discharged, uh, if they're clinically well, which most of them are in a couple of days of life, so. I think, uh, in an ideal world we would all have access to the prenatal images that have been obtained 3 or 4 weeks before pregnancy, we would know what that is, we'd assess the newborn, and then we'd make a decision based upon what the prenatal ultrasound images as to exactly when we're gonna get a picture. Unfortunately, we don't always have those imaging, and we just have a report that says, oh, maybe it's UTDA 1 to 2. Well, what does that mean? I don't know. Uh, and so, I think most times if we don't have the prenatal imaging available, we're gonna recommend probably getting an ultrasound. You know, before discharge, before the baby is discharged from the hospital, accepting that that might underestimate the degree of dilation and accepting that we're probably gonna need to repeat that ultrasound at 4 to 6 weeks just to make sure that it's uh what the what the real baseline is. But the, I guess the reason to get it early on is you don't want the kid that's really got significant obstructive neuropathy. To fall through the cracks and then get a febrile urinary tract infection and sepsis in a couple weeks of age before they actually, you know, come in for uh a postnatal ultrasound, and I think the newborn parents really don't wanna be carting their kid back to the, to the ultrasound suite 5 to 7 days of age while they're at home just trying to, you know, get used to having a newborn around. So this is the UTD grading system uh that I talked about, and it's uh maybe a little bit, it, it deals both with, uh, you know, it's more descriptive than the SFU. The SFU is pretty much just the AP diameter and a gestalt of what the KOSCs look like. But again, if you sort of look at it, you know, normal is probably SFU1, P1 is SFU 2. Uh, this is SFU 3. This is SFU 4, and then, uh, there's a lot more weight putting into the measurement of the renal pelvis, uh, again, whether it's KOCs, whether the reup is normal or echogenic, it's echogenic or abnormal princi, it gets into a P3, and if the bladder or ureters are normal, it gets you into a PT or a P3. And so again, like I talked about. If they're low risk and uh they probably don't need imaging as a before they leave the hospital uh if they're intermediate risk or higher risk, then again I think the recommendation is gonna be to uh get imaging before they leave the hospital. So this is the table that's in the uh. In the in the manuscript, so low risk again is gonna be less than 10 millimeters or less than 15 with just central caloceal dilation and uh they get one ultrasound and then the recommendation is sometime 3 to 6 months they'll get a a second ultrasound just to make sure that uh. That the dilation hasn't increased, and antibiotic prophylaxis is not recommended in these patients, and based upon the data, we know that this degree of dilation may have be associated with reflux, but that incidence of dilating significant reflux is small, so a cystogram is not recommended. So for the lower risk, historically, I think, you know, 20 years ago, probably every newborn with prenatal hydrophrosis was placed on uh. On, uh, antibody prophylaxis, but now I think that's not, you know, as commonly utilized because I, I think historically we we overutilized, you know, antibiotic prophylaxis. Uh, intermediate risk patients are gonna be again greater than 15 millimeters with peripheral case cell dilation or ureter dilation. They're gonna get follow up a little bit sooner, uh, and, uh, I think if there's a dilated ureter, it does increase the risk of reflux, and we would most times recommend antibiotic prophylaxis. Intermediate risk again may depend upon the gender of the patient. We'll, I'll show you some data later on, uh, that discusses that. Uh, and I think these, the yellow and the red probably, uh, you know, I think I would think if the ultrasoundstain before they get the leave the hospital, the best thing to do is, you know, contact us through Children's Direct more times than not, uh, we're able to, you know, view at least the postnatal images and come up with a management plan that's based upon, uh, our experience and I guess expertise, and then, you know, these high risk patients, I think. Uh, probably should be evaluated in the hospital by us, you know, uh, to make sure that there's nothing that needs to be done. Uh, I think typically these high risk patients, we've consulted them prenatally. If you have if you have, uh, access to Epic or we send a note to the, uh, OB and the, the planned pediatrician, our management plan will be, uh, you know, in that note. Uh, so what kind of imaging can you do? Well, an ultrasound's pretty easy. It's not noxious, it's not super expensive. Uh, it does assess, you know, pretty good anatomy scan. It doesn't assess function, and it's not real good at identifying reflux. VCUG can either be done fluoroscopically or with, uh, bubbles placed in the bladder under ultrasound. Uh, both of them involve catheterization, and that's the most noxious thing of it all, uh, as far as the parents are concerned, uh, and, uh, the advantage of this is it doesn't involve radiation, although with fluoroscopy, cystogram also has pretty minimal radi radiation. The last two tests here are reserved basically for children who uh. Have a significant dilation where we're concerned that the function may be diminished or we're concerned that the uh. Uh, You know, that there may be significant obstruction, so we want to evaluate for obstruction. Uh, The key recommendations of this paper are, I guess there's a couple of key recommendations. One is for gestation identified as low risk, if it resolves during pregnancy, you don't need an ultrasound postnatally. So if there's clear record that there was mild dilation of the renal pelvis, we know that most of that resolves, it's a transient neuropathy, they don't need postnatal evaluation. They're identified as low risk and it persists after 32 weeks, I think the recommendation is to get an ultrasound sometime. Between 48 hours and 6 weeks of life, but there's not a reason to get an ultrasound, uh, before they leave the hospital. And for newborns that were identified as increased risk, uh, at any time during pregnancy, uh, that was higher risk, I think we would recommend an ultrasound before they leave the hospital, and then, you know, doing some shared decision making determine whether or not they should be started on antibiotic prophylaxis, and uh when and if additional imaging should be obtained. Uh, for those patients with indications for postnatal ultrasound, again, the recommendation of the paper, based upon the available literature is that a minimum of 2 postnatal ultrasounds should be obtained prior to discontinuing surveillance, and again, those with intermediate risk, after their first postnatal ultrasound, you get another ultrasound, and then depending upon what those sign, the decision's made to proceed with BCG evaluate for reflux or renal scan to evaluate. Function and obstruction, and if you have ureteral dilation, this definitely increases the risk of UTI so we would typically recommend antibiotic prophylaxis, pending obtaining a cystogram, uh, which usually is not an urgent thing to obtain during the neonatal period, unless we have concerns that, uh, the kid has posturethral valves or or significant obstruction, and for patients who are high risk. Uh, again, we follow them more closely. We probably obtained a BCG and renal function imaging in most of the patients that are deemed high risk. So let me see, are there, is there anything in the chat here? This is kind of a transition point. Let's see here. Uh, Let's see. No, it's just CME stuff, right? OK. So, uh. As we've talked, not everything that is dilated is obstructed, and uh it's very difficult to tell from ultrasound alone, you know, whether or not obstruction is present, and so this would be a very common, again postnatal finding, you know, this may be a 3 month old, uh, that has very normal looking parenchyma, and some, you know, dilated, you know. Mindilation of your pelvis, a little bit of dilates the KOCs and vast majority of this will resolve. And why does it resolve? Well, there's normally little folds in the ureter during development, and there's normally obstruction at the level of the kidney and normally at the bladder during development. And over time these little folds do straighten out. This is a kid that actually had a pyeloplasty on the other side, and he has a stent on the left side, so I. Thought I would get a retrograde pyelogram to see, you know, why, why this is still dilated. Now the calyses are super delicate, and you can see the UPJ here is wide open, so you'd expect this is gonna, gonna improve, but this is the normal anatomic thing that probably these folds resolve in the vast majority of well male and female fetuses by, you know, 16 weeks, but sometimes they persist. You can also have just just angulation and folds without hydronephrosis. This is a 3D reconstruction of a CAT scan, right? So clearly the magnitude of dilation impacts how likely it is it's gonna resolve, and uh if the milder it is, you know, what, 60-70% resolved, it's severe or moderate, you know, 60% resolved, and so clearly there's a relationship between the magnitude of dilation uh and resolution, and years ago, uh, we did a study here. Uh, that prospectively evaluated, uh. Fetal renal pelvic diameters, and uh you know what I found is that an AP diameter of 22 millimeters was kind of the cut point. For uh obstruction, so you can see I mean you can have a kidney that has an AP diameter up to 50 millimeters, that resolved, right? Uh, at the same time, you can have with at 9 that turned out to turned out to have obstruction, and, uh, again, reflux is just kind of all over the map, and so, you know, lesser dilation again is less less likely to be obstruction, but even some minor dilations turn out over time to progress to obstruction. And so, this is a uh receiver operating characteristics curve, and uh basically a cutoff of 17 millimeters is accurate 85% of the time, OK? So 70% of the time, it picks up obstruction, so 17 m 70% of the time obstructive, and a specific 91% of the time, so the number of false negatives is very small using those cut points. Uh, but again, this is an example. So this is a kid that at 5 weeks had this ultrasound, I think was probably discharged from care, and then I think showed up, you know, at 56 years of age with some abdominal pain, and you can see that the dilation has significantly increased, uh, but this is another kid here that at birth, you can see that the renal pelvis is big enough, it's adjacent to the bladder, right? And with no intervention. It was normal looking at 2 years of age, so again, there's a lot about the dynamics of this, we can't get retrograde pyelograms on everybody to see if there's folds in the ureter or there's some abnormality that's causing this dilation, I think it requires, you know, patience and observation. Unfortunately, ultrasound is a pretty easy test to get. So it's just another clinical example of a kid at 2.5 weeks of age, again, pretty mild dilation on the right side, left kidney, normal in appearance. At 6 weeks of age, the right kidney was significantly more dilated, right? So based upon that finding that would now be probably a UTD P3, uh, I obtained a renal scan, you know, to further evaluate, and you can see the right kidney is significantly larger, uh, than the left kidney. And you can see here that the left kidney drained out spontaneously on its own, but the right kidney, uh, was normal in appearance, but if I go back to the previous slide here, again, if I go, uh, if I look at the function where it's fifty-fifty. Almost always, if they're asymptomatic at this young age, and it's symmetric function, we're not gonna rush to operate. I think there are some centers around the country who would operate, uh, but I think there's good evidence that observation in a short time in the absence of infection, there's very low risk of loss of the function over, you know, several months' time. So again, didn't drain well, uh, but and so this is the summary again, 50% function, drainage was slow, uh but then 4 weeks later. You know, the ultrasound looks good, right? So, uh, you know, did he have some inflammatory polyp where he had a little stone that was clinically, you know, but stones don't form early in 6 weeks old who aren't in the NICU getting Lasix, uh, you know, what's going on there? And then repeated an ultrasound at 3.5 months, and again, the function's fine, but it drains perfectly fine. And then, you know, at 4 years of age, that kidney looks perfectly normal. So again, there was something about, I guess the folds in this uh ureter, he clearly didn't have a a a fixed obstruction, uh, but it did improve, so I think that's the nuance of what we as pediatriologists do is trying to, you know, use our experience to try and figure out who needs surgery, who can be observed, uh, and that type of thing. So we talked earlier about, you know, magnitude of dilation and, and the risk of UTI. So, uh, this is a study from a couple of decades ago. Uh, girls clearly have a higher risk of UTI, you know, after the 1st 12 months of life. So it's in boys in the 1st 6 to 12 months of life. Do have a slightly increased risk of UTI. Some of that may be related to the circumcision status, but even, uh, even circumcised boys in the 1st 6 to 12 months of life have a slightly higher risk of UTI, probably related to some, you know, voiding, congenital voiding dysfunction, some discoordination between the bladder and the sphincter. The magnitude of dilation also plays a role, like I said earlier, the more severe the dilation, the more likely they're gonna get a UTI. So in this, you know, in 3 years of time, what, 30-40% of children that had what was deemed as severe dilation had infections, whereas in the ones with the mild to moderate, somewhere between 10 and 15%. So, you know, the risk factors for UTI are female gender. I think intact foreskin in the 1st 6 months does increase risk, uh, more significant degrees of dilation where there's, you know, ploceaccesses and cortical thinning, you get a dilated ureter. We don't know if they have reflux just to pay the ultrasound. If we knew they had reflux, we know that reflux does increase the risk of UTI and then, uh, you know, obstructive neuropathy like valves or. Something like that clearly increases the risk of UTI. So, you know, antenatally detect a reflux, obviously if you had a crystal ball and we knew who had reflux, then we wouldn't have to get a cystogram, uh, but the goal is obviously to prevent infections, uh, to prevent renal scarring, but the question is who do you screen and, you know, who do you start antibiotics? And again, the, the manuscript I think addressed that pretty well, uh, although it's still, I think you're gonna. Overtreat some patients and you're probably gonna miss some patients, I mean, you just are, uh, but we just can't start antibiotics in every single kid that has prenatal identified hydrophrosis, uh, as far as antenatal detection reflux, if we tested every single kid that had dilation, if we did cystograms and you know, back in the 90s, I think there were a few studies that did that, and the incidence varied, it was somewhere between. You know, 10 to 30 or 40% of the kids that had cystograms did have reflux, uh, it was clearly male predominant, but that's largely driven by the fact that males are more likely to have dilation, which then would result in getting the cystogram, uh, but the incidence based upon, you know, if you normalize for the frequency of the hydronephrosis, the incidence of males it feels the same. And I think there is clearly a significantly lower risk of reflux in African Americans than there are in Caucasians, uh, so again, what's the risk of missing reflux? Well, the overall incident of scarring is very low, it's low enough, is it low enough? Uh, scarring can be severe. I mean, certainly you can have one infection that can do significant harm to the kidney. The grade of reflux clearly has been shown to correlate with scarring, so someone with grade 5 reflux is more likely to have scarring than someone with grade 1. There's good evidence that the more episodes of UTI you have, the more likely you have scarring, and there's good evidence that delaying therapy can also be associated with increased renal injury. So this is a study, again that evaluated uh kids that whether you knew they had reflux or not. So uh a primary mega ureter uh would be a dilated ureter without reflux, has a slightly increased risk of of UTI. So in this study, I guess, uh, 60% of kids didn't have a UTI. Uh, if you had reflux, it was actually, you know, 3/4 of those children had a UTI. Uh, if it's just isolated hydrophrosis level kidney, it's actually a very small percentage of kids who get UTI. So postnatally, again, ideally have somebody do the prenatal imaging. Uh, I guess if you err on the side of putting on antibiotics for a week or two and get an imaging, that's not the end of the world. Uh, statistically about 20% have reflux, but we don't necessarily identify all of those kids. Uh, reason being, at least in Saint Louis and the Midwest, the vast majority of boys are circumcised, and circumcised boys with very little reflux almost never get infections, and, uh, if they don't get infections, they don't need to be on prophylaxis, and we're not gonna talk about it reflux typically resolves, so, uh, that's why we don't necessarily have to identify every reflux, uh, again, we would selectively use antibody prophylaxis, uh, but again, if the ultrasound is like this where. You know, there's some dilation of the kidneys, not terribly obstructive, but down at the level of bladder, there's a dilated ureter, those are things that would increase the risk or the thought that we need to get a cystogram. So for example, this kid had a cystogram and he's actually got pretty marked bilateral, you know, hydronephrosis reflux, grade 5 reflux bilaterally, but has a normal urethra without obstruction. The chat again here just a second there. Uh See, do you have any recommendations for hospitals where we do not have renal ultrasound available prior to newborn discharge? Is there mechanisms to get a more urgent ultrasound or better to have an urgent outpatient urology appointment for the A23 crowd? Uh, Again, most of the time, you know, if, if we know, you know, it also like here's an ultrasound that was obtained at 36, 37 weeks of pregnancy or even at whatever. That's not gonna change probably significantly between then and the time they're born, it's just not, and so I think if we look at those images, we can make the decision based on the prenatal imaging uh whether or not they should be on antibiotics or not, and then an ultrasound could be obtained at probably 7 to 10 days of age, right? So if it's, you know, we put them on antibiotics on the presumption they have reflux, we've, uh. Looked at the ultrasound, we don't think, you know, the kid's clinically well, it's wedding, they don't have, you know, colicky symptoms from obstructed kidney, then there's not an urgent reason, uh, to, uh, get the ultrasound if it's not available at the birth hospital. And yeah, I think if you called us, we can get him into the office at 7 to 10 days to, to get a, uh, an ultrasound and start the evaluation. I think that's fine, uh, so I, I think fortunately MFM and OB has been much more. Willing to uh put their images out there. I mean, even as recently as, I don't know, 67 years ago, I would have to walk over to our OB office to actually look at the images, but now they're immediately available in Epic for me to look at, you know, and uh I think other systems with uh Phare that we have through Epic. Uh, most hospitals in the region, my nurses can get them to electronically upload the images to our system, we can review them. It takes, it takes some effort, uh, but I think we can do it, but I think it's not the end of the world if you don't, uh, have the ability to get an ultrasound before the kid's discharged. All right, so posterurethral bowels, what are they? So it's a, it's a congenital obstruction of the male posteri urethra, and uh because of that, then you end up with a distended bladder. And dilation of the kidneys, and sometimes this obstruction is significant enough that there's oligohydramnia, so this baby doesn't have any amniotic fluid around it and massively dilate kidneys, this baby here, here's the dilated prostate breather has an obstruction in the urethra, but has normal amniotic fluid. Uh, and on ultrasound, sometimes we would see again super echogenic kidneys. This kid actually has got a perinephric urinoma, so the, this is a fetal ultrasound. The kidney parenchyma is super echogenic, and then adjacent to is this perinephric urinoma. This kid actually has a pretty decompressed bladder and urinary ascites, uh, from transudate. So, uh, it's the most common cause of lower urinary tract obstruction in male neonates, uh, 1 in 5000, 1 in 8000 live bursts. Probably a little more common, but a lot of these kids have significant obstruction that they, you know, don't survive the first trimester, right? So I think the incidence is probably a little bit higher, uh, or significantly higher, uh, than what we see as newborns, and, uh, valves are the most common urologic cause for, uh, renal failure and transplantation in children, and so historically there was a super high mortality. Uh, but now with, uh, improved perinatal care with, you know, ventilators, oscillators, I think the, the lung maldevelopment, uh, kids can make it through that, and, uh, end-stage renal disease management is better, uh, I think the, uh, the neonatal survival is much better, but still, you know, 20 to 50% of. Males with a history of bowels are gonna have some degree of renal insufficiency. Not all of them are transplant, but that many of them will not have ever have normal renal function. So basically two types of bowels, the type 2 valves, I think, uh, I didn't draw a picture because most people think they actually don't exist. The type 1 is the most common, and it's, uh, basically a cell you can, if this is the prostate, and this is the beer of Montana, where the ejaculatory ducts are and the bladder's up north here. When they pee, these, uh, basically the sail catches the urine or the wind and, uh, obstructs the obstructs flow. Type 3 is actually more of a, just a membrane, uh, that in some ways just passing a catheter. Catheter actually does a good job at least partially disrupting the bowels and, you know, again, classically they presented with UTIs, abdominal masses, and Potterspacey. Now they present, you know, prenatally, the vast majority are identified prenatally, although, uh, oftentimes it's after 24 weeks of pregnancy, uh, so sometimes it is missed with the, uh, you know, the early ultrasound. If that ultrasound is pretty normal and they don't get any other imaging during pregnancy, it'll be missed. So, you know, again, failure to thrive, neurosepsis. Typically, uh, you know, we just rarely see that now as a presentation. So again, they're gonna be these ecogenic kidneys, a super thick bladder, and dilated ureters, and uh again you can see here how thick and muscular this bladder is, and there's a blockage here in the urethra, and then there's back pressure that's causing reflux of urine up to the kidneys, and so this is just a picture of what valve leaflets look like, you're looking retrograde into the towards the bladder, and these are the little leaflets here uh that are causing the obstruction. And so typically most kids are big enough and we've got small enough endoscopes, uh, that as long as they're not uh significant prematurity and have a small urethra, we can endoscopically go in and either, you know, ablate it with an electrode or a loop or a laser uh to get rid of the uh valve leaflets. And that's not the end all. Uh, there's, like I said, there's long term issues with kidney function, there's long term issues with bladder function, there's long-term issues with polyuria in some kids that adversely impacts to training. Uh, I think that's beyond the scope of, you know, this presentation. I think that's, uh, once, uh, they're hooked into the system, they stay hooked in the system because they, they have long term issues. Uh, with both bladder function incontinence and their kidney function. Let me check the chat here again, let's see here. OK. So next is UPJ obstruction, so that's gonna be obstruction of the level of the renal pelvis and the renal pelvic junction, and, uh, most newborns, if they actually have significant obstruction, it's gonna be an intrinsic narrowing, whereas older kids who show up with abdominal pain or intermittent episode pain oftentimes have a crossing vessel, so the renal artery branches out, and then there's a lower pole vessel that, uh, intermittently obstructs the, uh, ureter. Uh, again, prenatal, we talked about it, you know, kids that have the marked dilation, we get renal scans, we follow them, uh, if they have, uh, stable function, decreasing dilation, then the thought is they don't have significant obstruction, they can be observed, uh, kids we operate are ones that have, you know, increasing dilation or diminished function and poor drainage at the time of presentation. Older kids present with abdominal pain, and oftentimes they've had abdominal pain, you know, kind of for years, you know, once every month or two, and it's kind of nondescript and, you know, maybe it's because they ate some bad food or, you know, just not severe enough to warrant evaluation, but then they'll they'll show up to the emergency room and either get an abdominal ultrasound or a CT scan that then shows, you know, marked dilation of one of the kidneys, so. This one, there's delayed excretion because there's acute obstruction and the renal pelvis is, uh, significantly stretched up, so, uh, this is a kid, you know, that clearly has a UPJ obstruction, it's usually intermittent, it's very rare that we have to intervene acutely, uh, it's sort of like a kidney stone, the, the pain occurs, there's obstruction, the prostaglandins kick in, the blood flow to that kidney. You know, is decreased for a short time, the hydrophresis goes away, they get better, and, uh, then they can be, you know, treated on an elective basis as opposed to, uh, urgently. Uh, again, decreased differential function, severe UPJ obstruction, like I said, increasing hydronephrosis or loss of function over time in the kids that have prenatal identified dilation, uh, recurrent UTIs or stones in the in the conjunction with the dilation. Uh, again, isolated UPT is pretty rare to have recurrent UTIs, uh, but we do see sometimes. Uh, especially, uh, you know, some girls that, even though they don't have reflux, do seem to get, uh, recurrent UTIs, uh, with involvement of the hydronephrotic kidney, and so the, the standard treatment is what's called a dismembered pyeloplasty, and the principle is to form a, you know, nice funneled, you know, drainage with a, you know, tension-free and watertight anastomosis and. Uh, this is just, uh, uh, some pictures, uh, of, you know, laparoscopic robotic poplasty. So here's the vena cava, here's the ureter. This is the crossing vessel here, and so the, it's dismembered, OK? And then it's sewn back together with the ureter renal povus going on top of those crossing vessels. So again, this is what it looked like beforehand, and this is what it looks like afterwards, so you, there's oftentimes a little bit of a narrowing fibrosis in that segment. Because of the pressure and intermittent inflammation. You cut that out and you rearrange uh the the drainage, and you know, 98, 90% of the time that's the end of the story that it heals perfectly and they don't have a recurrent symptomatology. So the second most common uh site of narrowing is down by the bladder where the ureter joins the bladder, uh, and those are called mega ureters, and some of them are refluxing, some of them are obstructed, and I guess uh the majority are non-obstructing and non-refluxing, so, uh, again, you can be born with that type of thing if you had spina bifida or valves or something, that's what's called a secondary refluxing ureter. Uh, usually it's related to an adynamic segment, so ultrasound is gonna be a dilated kidney, but also a dilated ureter coming out of the kidney, and then down by the bladder, a dilated ureter by the kidney, and some of these mega uterus reflexes, a cystogram. In a male, uh, they started to pee and then you can see there's reflux, the distal ureter is a little bit narrowed, and then there's reflux into this remarkably dilated ureter, and that occurs because the distal segment is, uh, is adynamic. There's, uh, you know, abnormal deposition of collagen and not quite as much muscle as there should be, and there's ineffective peristalsis, so then proximately, this dilates up and so like a renal scan. Again shows pretty symmetric function, but then there's markedly dilated ureter going down to the bladder, uh, fortunately, the vast majority of megaures that the ureter has a lot of capacitance. It, it makes it so there's not a lot of pressure on the kidney. And uh because of that, then uh the kidneys typically work perfectly normally, and there's very good evidence that these resolves, so we don't do intravenous pyelograms anymore, but this is a study from CHOP where I trained a long-term study, and you can sort of see this was a mega ureter at birth, and then this is a follow-up, right? So the right kidney looks pretty darn normal with no surgical intervention. And again that's because the distal ureter remodel, so mega ureters are much more likely uh to improve when compared to uh. To a UPJ and uh most megaureter, at least in boys, if they don't reflux, aren't associated with UTIs. Some megaureters in females, depending on how dilated they are, there is some risk of increased UTI and resolution, you know, it's clearly related to how dilated the ureters is, but even up to, uh, you know, 1415 millimeter diameter distal ureter, uh, they do resolve, and you can see just percentage wise, the vast majority resolve. If they don't resolve, then we have to reimplant the ureter, so basically you need to somehow make the ureter narrower, get rid of that distal segment here, and then reimplant it in the bladder, and that's typically very, very successful. Duplication anomalies are pretty readily and easily identified during pregnancy. So this is actually a kid with a duplication anomaly that doesn't have marked hydra at this time. It's pretty early in pregnancy, but you can see if this is the kidneys. There's two collecting systems on each side, and, uh, I, I forget if this progressed through time, but basically on a postnatal ultrasound. You're gonna see a normal lower pole of the kidney, and then the upper part of the kidney is dilated, and the question is, as the ureter goes down there, is it obstructed because it's an ectopic ureter or is it obstructed because it's ureters so, so it's very important to get a bladder image with. These patients, and so, for example, this patient, here's a bladder, the ureter is outside the bladder and goes down here, this kid here, down in the bladder, there's a urethrocele, so the distal end of the ureter balloons into the bladder kind of like a cobra head. And this is just a diagram of what a urethrocele looks like, there's a duplication, there's a lower pole ureter, and the upper pole ureter balloons out here. Sometimes it's intravesicle, and sometimes it's ectopic, so the opening is outside the, the bladder, and again, this is just what an ultrasound looks like on a cystogram, it's this filling defect inside the bladder, endoscopically, this is what a urethrocele looks like, it's just again this ballooned out area inside the bladder, and if you have a urethrocele. Then typically the upper pole because it's obstructed uh has diminished function. It just didn't develop normally, it's got some dysplastic uh elements to it uh we also know that if you have uh duplication, uh, there's, it's very likely that there's reflux into the lower pulmoides, right? And so, uh, kids with a duplication that's detected prenatally, I think 100% of the time we recommend antibiotic prophylaxis postnatally, uh, pending additional elevation because historically, that's pretty much how these kids showed up, they showed up with urinary tract infections, uh. And uh you know, sepsis, and this is just a cystogram that shows the magnitude of reflux that you can see in a duplicated system, so this is reflux in the lower pole on the left side and there's reflux into both moides on this side. So again, why do we intervene as neoates in these kids if they have uncontrolled sepsis or they have azotemia from bladder outlet obstruction. So for example, in this patient with ureosto, this is a little bit of dilation of the lower pole, which you can see there's some debris. In the upper pole, uh, and that's, you know, pus, right? So it's an obstructed system with pus, and in a kid like that, typically if it's a urethrocele, we're gonna do an urgent procedure where we look through the urethra with an endoscope and then puncture the urethra urethrocele to, uh. To uh relieve the obstruction, and, uh, this is a kid who actually showed with a prolapsed urethrocele, so an entroidal mass in a newborn, uh, and it's a prolapsed urethrocele, which you could confirm on ultrasound, it's actually pretty easy to manage, you just puncture that in the emergency room and drain the pus out, and the urethrocele sucks inside the next morning or urethra or bum look perfectly normal and the dilation goes away. Like I said, incision, we look inside and we take a little electrode, we puncture that and drain it, OK? ectopic ureter means that the ureter doesn't insert into the bladder, so this is a reflexing ectopic ureter, but you can see here that the ureter, uh, inserts into the proximal urethra. Uh, and this is reflux that won't resolve. It's reflux that does increase the risk of infection. So again, like I said earlier, if there's a duplication abnormality identified during pregnancy, we would definitely recommend starting those patients on antibiotics, uh, in the in the postnatal period. ectopic urges in females are a little different than in males. So embryologically, the ureter again follows the, uh, the wolffian duct, and, uh, sorry. And the uh. In males, that's gonna be proximal to the sphincter, but in females, the wolfing ducts becomes Gartner's duct and actually is on the anterior wall of the vagina, so females with an ectopic ureter, uh, untreated, typically gonna have a continuous urinary incontinence. And so I think, you know, when I was a resident early after I finished fellowship, when a prenatal ultrasound was not as widely utilized, uh, you would see like a 3 or 4 or 5 year old girl in the office and the parents say, oh, they, we know they're potty trained, but they just got damp panties all the time and uh you know, the way to sort of figure that out is, you know, well, if you put new underwear on, is it wet 10 minutes later? Is it damp? Yeah, are they. Big accidents, no, it's just damned, and so then imaging would typically identify uh the uh abnormality, and so again this is just the embryology here where uh the Wolffian duct or the mesonephric duct in the female goes down here, and again the bud came off that and it's in the wrong place. So this is uh like a 4 or 5 year old girl who showed up with continuous incontinence and. The kidney ultrasound looks pretty normal. This is her vaginal opening, and here's her urethral opening here. This is a catheter going, uh. Inside this little wolf, this mesonephric duct here, right? and it opacifies this little bit of nub that's making probably, who knows, 1 teaspoon of urine a day, but enough to make your panties damp and drive the parents crazy. This is, uh, if you have a duplication, like you have UPG obstruction to the lower pole. So just, uh, again, you might oftentimes we detect that during pregnancy if you had dilation like this, it's either obstruction or it could be reflux to the lower pole because reflux again is more likely to the lower pole. So it's another thing, it can't be identified during pregnancy. This is actually a kid that probably showed up at an older at an older age with abdominal pain since there's a CT scan here and uh, you know, basically this kid had. An incomplete duplication, but there's a crossing vessel here that caused obstruction. So, uh, reno agenesis, so renogenesis happens because the ureteral bud didn't form on that side or because the uh. Metanephrine, something was wrong with it, and uh it's a little bit more common in males, and again there's some. Misinformation or dissent about how that interaction occurred on an ultrasound, what you see is you see a flat adrenal gland and no kidney, so the adrenal glands typically triangular, but if you have renal agenesis, there was nothing there to deform the adrenal gland, so the adrenal gland is flat. So you could have a, an absent kidney or you could have an ectopic kidney. We'll talk about that, but, but this means there was never a kidney in the in the right renal fossa. In females, this becomes important because if you have, because the Mullerian duct. And the uh Wolffian ductor next to one another, if there's an abnormality with the uh Wolffian duct, then it's more likely they're gonna have some uterine or Mullerian abnormality. So in patients that have uh uh. Unilateral females with unilateral renogenesis, about 10 to 15% are gonna have significant or even more than that, probably a third to 1/4 of them are gonna have some uterine anomaly, typically not of any concern in infancy, uh, becomes apparent at. Uh, when they start menstruating, that there's an anatomic abnormality, so there's really nothing to do with a neonate, uh, but oftentimes try and counsel the parents that, you know, at puberty, they're gonna need to have follow-up to make sure there's nothing, you know, abnormal, so multicystic dysplastic kidney, the kidney formed. Uh, but, uh, the ureter never opened up, so then it became a bunch of cysts, uh, in a non-functioning kidney, and, uh, sometimes there is UPJ on the contralateral side because again it's a genetic bud abnormality, sometimes there's reflux, but. If the imaging of the contralateral kidney has has been entirely normal throughout pregnancy and postna go a normal, then typically we don't, do not get cystograms on those patients. Uh, studies have shown that yes, you do find reflux, but again, it's typically low, low grade reflux. That's gonna resolve, so typically do not get imaging with any other cystogram and don't start them on antibiotic prophylaxis, unless there's some abnormality of the contralateral kidney, so typically these involute, uh, and uh the other side goes undergoes compensatory enlargement, uh, and the kidney function is typically normal or near normal, uh, there's no higher risk of hypertension. And there's really not felt to be a higher risk of malignancy in these dysplastic kidneys. I think, uh, Beckwith of Beckwith Wiedeman, a pathologist, you know, looked at all of the Wilms tumor data and really doesn't find that there's an increased incidence of, uh, Wilms tumor in these patients. Uh, the kimono study was an evaluation of kidneys, of the monofunctional kidneys, right? So, uh, if you have a. Solitary kidney that you were born with, and the other kidney is normal, right? So the contralateral kidney is normal, again, they're typically gonna have perfectly normal renal function, if the contralateral kidney is abnormal, there's a small percentage of those kids that don't have entirely normal renal function, so those are kids that, you know, they may have contralateral reflux, they may have contra UPJ. Uh, those are kids that, uh, need to be followed very closely by nephrology, uh, but the vast majority of children with a solitary kidney that is normal in appearance, uh, on postnatal imaging are gonna have normal kidney function when they're an adult. As far as athletes, you know, I think the American Pediatrics, I think there's no absolute contraindication to contact sports, but I think parents need to be con you know, uh. Educated and counseled that, you know, if they, if they had to make a choice, they probably would choose that their child, you know, played soccer or baseball or basketball or volleyball or something like that as opposed to, you know, ice hockey or football or cliff diving or motorcycle racing or something else, it's just an increased risk, although we know as urologists, most trauma that we see to kidneys doesn't happen in sports, it happens in. You know, my kid drove their bicycle into the telephone pole where they were in an automobile accident or something like that. Fortunately, most renal trauma heals on its own. It's very rare that we end up doing, uh, nephrectomies. I think parents still need to be counseled that uh. That you know they need to think about limiting that, so pelvic kidney or an ectopic kidney, again, it's most commonly in the pelvis, failure to ascend, they can have obstruction, they can have reflux, and maybe it's a little more susceptible to trauma, but you don't move it. Uh, but again, if it's normal without hydronephrosis, typically we do not get a cystogram to evaluate for reflux, but this kid here has a pelvic kidney, this is the bladder has reflux into the pelvic kidney, so that kidney had some hydronephrosis, like a pelvic kidney with some abnormality, ecogenic hydrophrosis. Probably needs antibiotics and needs a cystogram to further evaluate. Fusion anomalies would be the two kidneys are stuck together. The most common fusion anomaly is a horseshoe kidney, so the two, lower poles of the kidney are fused together. This is an ultrasound showing the spine, the aorta and the vena cava, the kidney draped over it. This is just a CAT scan showing that there's a slight higher incidence of obstruction. In these patients, but again, they can be followed, and if there's no hydrophrosis, they don't have to be followed super closely. If there's hydronephrosis or dilation of moiety, there is increased risk of reflux, so then we would probably recommend a cystogram. Horseshoe kidney it's pretty low incidence, but if you have a horseshoe kidney, there's a higher risk of Turner syndrome, because about 60% of Turners do have, uh, horseshoe kidneys. It's also much more common in trisomy 18, and then crossed ectopia, uh, is, uh. You know, also another fusion abnormality, the same thing, if there's no hydronephrosis, typically don't get any further imaging, don't do any further evaluation, so I'm gonna stop there. Created by Presenters Douglas E. Coplen, MD Pediatric Urology, Urology View full profile
