Hydronephrosis? 20 wk scan increased DS risk...

[Umnitsa]

I am expecting a first baby at 39. My background risk after the 12 wk DS screening was 1:2080 which was pretty good given my age, but at the anomaly scan yesterday the sonographer identified a mild marker for Down's, mild hydronephrosis, plus two hyperechogenic focuses in the baby's heart ventricles (which, apparently, is innocuous on its own but in combination with any other markers becomes a DS marker as well). As a result, my risk was divided by a factor of 8 and is now 1:261 - still medium rather than high risk group.

The sonographer offered an amnio - either immediately or at 32 weeks, and started talking about termination which was too much for me. Given a 1:100 risk of miscarriage vs 1:261 risk of DS I don't think I can risk an amnio now, might do it at 32 weeks when even if the amnio triggers premature labour the baby will be viable.

The last 12 hours have been a haze. I tried to find research on the correlation of hydronephrosis with DS, and where the factor of 8 comes from, but without much success. Interestingly, whilst our sonographer was checking the results with the consultant, we had a chat with her colleague who actually said the scan results had DECREASED our risk - she was looking at the length of limbs, presence of finger falanges etc which were all fine...

I guess I need a second opinion on the interpretation of the results. From various MS threads it seems that the FMC is the place to go, but I am with King's College Hospital where the antenatal service is run by the same Prof Nicolaedes so not sure if I should go to his private clinic to question the results of his NHS clinic.

The truth is, we are not going to terminate in any case, but the uncertainty is just killing me. Plus I am concerned about the consequences of the hydronephrosis - not as a marker for Down's but as potentially leading to kidney problems.

Apologies for the long rant, I am just wondering if anyone has had an experience with this or could direct to any useful research. Thanks.

Hi. Really sorry you're going through. I had hydrophrenosis detected on 20 week scan with all 3 of my dds, plus with dd3 echogenic foci just on the border of the heart. I've done a lot of research on this (also work in antenatal screening so pick up info constantly) and hydrophrenosis (also interchanged with pylectasis a lot of the time) is by many people now seen as a very weak 'marker' for ds. I know in Wales (where I work) hydrophrenosis is discarded as a marker for ds (as is echogenic foci - that's not even reported if seen in isolation). Hydro is reported, but only because they need to keep an eye on it as while it usually resolves it can on occasion be caused by a blockage that will need a small op about 10 mths after baby is born. All my dds were scanned after birth (at 6 wks), dd1 put on antibiotics as many babies with this are as they want to try and prevent kidney infections which can cause scarring to kidney, and all 3 rescanned at about 6 mth intervals. Had resolved in all 3 by 10 mths. The sonographer I last talked to says that they're now starting to see this as simply a variation on the norm as almost all cases resolve (it's caused by a reflux where the urine backs up to the bladder - the tube straightens out in time and the reflux resolves).
So please don't panic...easier said than done I know. I had amnio with dd1 (also had high risk result on triple test) with a culture failure, so the nightmare and stresses continued...Hope this helps a bit anyway xx

Hi Diege,

Many thanks for sharing this, I am delighted that your little girls are well despite having the same concerns at birth!! And what a relief that hydro is not universally considered to be a DS marker.

Given your experience with antenatal screening, do you know what formula is used to factor in such mild markers in the calculation of DS risk probabilities - are they all equal weight? Would doctors typically double the background risk to account for a mild marker, or every additional marker massively increases DS probability and the risk elevates ten-fold or eight-fold as advised by my sonographer?

Again, thank you for your kind words and for shedding some light on it.

No problem, glad I could help a bit . Re: markers and risk calculations, again there are no hard and fast rules. It does differ by Trust (and country - USA far less relaxed probably because of litigation risk). So for instance in Wales your risk would have stayed the same (what they call 'background risk' based on age, or recaluclated risk based on any screening tests taken - eg. nuchal fold wouldn't be affected by the 'markers' seen), other Trusts (eg. in England still see controversial markers such as hydrophrenosis/pylectasis, choroid plexus cyst) as worthy of multiplying risk by 8 for some odd reason. Having said that, new rules are coming in (should have been in by this April) that are more in line with those developed by Antenatal Screening Wales, which only increase the risk if such markers are seen in conjunction with structural markers (eg. cystic hygroma, echogenic bowel). And then other places according to ARC don't even report isolated markers such as echogenic foci in heart...My own hospital didn't actually add on a risk with my cases. So as you can see a huge mindfield, with lots of recommendations and hospitals slowly changing with new evidence-based research.I think the confusion between your consultants, sonographer/her colleague probably reflects the state of play I've mentioned above!
I'm actually interviewing a few screening midwives and a sonographer as part of a research project I'm doing tomorrow, so will try and add on a few questions about scans
I really hope you can get some reassurance on this - my first pegnancy was really spoiled by all the undertainty, though I was a dab hand at these 'markers' by no.3...

I was told dd2 had hydronephrosis at my 20wk scan. Was scanned throughout and delivered at 41 weeks normally. DD2 scanned at 5 days and put on small dose antibiotics. Rescanned regularly. She did get some UTI's which needed hospital treatment.

My dd2's did not clear up and she need to have part of her left kidney removed. However she is now super fine and throughout all of this she developed fine and you wouldn't have known she had this condition at all.

Mine is the probably a worst case scenario but it is not the end of the world although I know it does feel like it. She is also very proud of her scar!!

At no point did the consultant ever mention DS to me.

I never got a straight answer until I insisted on a consultant scanning me for the rest of the pregnancy. He was experienced in these matters and a very rare find.

Umnitsa - I am a paediatrician so thought I might be able to offer some advice about hydronephrosis from the postnatal point of view. As I have worked in 7 different Special Care Baby Units with 10 years of paediatric experience I can tell you that it is really common for scans to pick up a degree of swelling within the kidney, especially on earlier scans.

Most hospitals have a slightly varying policy on how they manage these babies, but I can tell you that on the later scans things have often either settled back to normal or the degree of dilatation is lessening (usually by 36 weeks). Where there is persistent swelling, once the baby is born they will either have a kidney scan within the first few weeks (again it often resolves spontaneously) or a more urgent one if the swelling is very marked.

The two causes we try to exclude are a degree of obstruction to the drainage of urine from the kidney; or reflux, where urine goes back up from the bladder to the kidney and distends the collecting system. In these cases there is an increased risk of urine infections, so the little one is usually given a low dose of antibiotic every night time to prevent urinary tract infections as anything that holds up the flow of urine can make things stagnant and increase infection risk. These are completely safe even in long term use and are stopped as soon as things seem to have settled. Depending on what the postnatal scan shows we also sometimes have to do another test to look for reflux (but it's less common for us to have to do that).

Even if there is a significant degree of hydronephrosis, there would only be a major impact on kidney function if the drainage to both kidneys are "blocked". It is extremely rare for the baby to have a serious problem with renal impairment/failure. If the subsequent scans picked up a blockage from the kidney, or very significant reflux these are both things that can be fixed.

Off the record, I can also tell you that the VAST majority of babies I have looked after with this problem have been otherwise completely normal (and I cannot think of a Down's baby who also had serious kidney problems related to hydronephrosis on the scan). In most hospitals I have worked in they are also happy to get a Paediatrician to chat to you antenatally to discuss the management plan if you are very worried and the problem persists.

Is this helpful? Sorry if information overload! Let me know if you have any other questions!

Kitty

Hi Umnitsa, firstly, congratulations on your pregnancy! It seems a very long time ago I was in your position with DS1 who will be 7 this year. He also had hydronephrosis but had something called PUV as well (Posterior Urethral Valves) which was so severe his right kidney didn't develop properly. His left overcompensated and is now the size and a half of what it should he (we call it his "super kidney").

He was put onto trimetoprim antibiotic for the first year of his life, and like ditdot DD, he had to have a nephrectomy when he was 4.

He is the most active 6 year old I know and is absolutely fine and dandy - we just have regular check ups. At no stage was downs ever mentioned...

The medical advice given by kitty is wonderful, but I would just like to add if there is anything you are unclear of then to call your hospital - I did numerous times..

Oh, and DON'T google...that was the worst thing I did as just read awful worst case scenarios...

Good luck

This is so incredibly helpful, I feel almost fully reassured now, thank you very much for the moral support!! Not to be cavalier about possible renal complications, this is still treatable and seems far less scary than DS...

Pixierara, Ditdot - I am so sorry to hear what your little ones had to go through, must have been a nightmare for you, but how wonderful to know that even in most difficult cases this can be fixed and a happy active kid still remains a happy active kid!

Diege - thanks again for the insight into the dynamics around what is and is not recognised as an issue in different trusts. It becomes almost a metaphysical question, does not it: what is the meaning of "healthy" if one can be pronounced fine in one jurisdiction and turned into mush by anxiety across the border just because the interpretative guidelines are different!

Kitty - thank you so much for the clear measured explanation of the diagnosis and possible developments, I feel much better now having understood the options and what we need to focus on. I am having a renal scan at 28 weeks but will try to talk to a paediatrician before that as well. Do you work in London by any chance, and if yes, could you recommend paediatric urologists who in your view are really good?

My little girl has been more active than usual today, kicking all day long (I think she is trying to tell me she is fine and I should stop worrying and pick her a name instead!!)

xx

PS My husband has been slightly dismissive of my new "mumsnetting" hobby, but having read your responses he is now a fan, really very impressed with the quality of advice and support one gets here!

umnitsa we are in London - DS sees Mr Steve Capps (who also operates privately and did his nephrectomy at St George's) and De El Rifai. She is amazing! The name of the consultant who we saw antenatally escapes my mind..I can find out if nobody else can help you???

Thank you Pixierara! I will check who would be the right consultant for us to talk at King's, whether they have anyone specilising in antenatal renal problems, or could refer to experts in other clinics.

Hi, spoke to the sonographer today that I mentioned and she confirmed that if you'd have had your scan in Wales they wouldn't have given you an increased risk for ds. They wouldn;t have mentioned the echogenic foci as it's deemed not significant as a marker for ds. They would have recorded the hydro, not because of any link with ds, but because of the need to monitor any possible reflux through future scans. Best of luck! Remember, it is possible that the hydro will resolve itself totally after birth as was the case with my 3.

Thank you for raising it with the sonographer, Diege, sounds very reassuring! Still, I cannot get my head around the fact that they started a discussion about termination with me at King's based on a totally insignificant marker for DS yet failed to explain kidney implications...

I agree, I think the massive decerpancy in the 2 reactions reflects the lack of consensus in general about 'markers'. Even so, I think talking about a termination after what is only a screening test (the scan) is at best poor bedside manner, and at worst goes against what current evidence from research suggests. My sonographer actually got really cross about your experience when I told her but said she'd heard that sort of thing going on before so wasn't really that surprised...