US showed cysts on kidney and blockage... any info?

My new SIL is 30 weeks PG with her first child. Morphology scan at 18-20 weeks showed a cyst on one of bubs kidneys, she was told it was pretty common and may resolve itself but they would keep an eye on it...
she was referred to have another scan at a private scanning place, they said there is a blockage in one of the tubes to the kidney as well as the cyst. Told her some other scary stuff too (my memory fails me at the moment)
She then saw a specialist the other day who has booked her in for another scan this coming thursday (through the hospital) specialist was not happy with what the US place told her, or the quality of the scan.
SIL was told there is a high probability of the kidney being reabsorbed by the baby, or baby needing surgery at birth to remove kidney or blockage..
She is quite calm about it as she knows that there is nothing that she can do, but wait, but she is scared, (as anyone would be!)
Does anyone have any info or personal experience that they would be willing to share? I have encouraged her to join up here, not sure if she has yet, but I know you ladies are full of helpful info that could possibly help her :)
Thank you.

I don't know of any babies that have only had a cyst on one kidney. I know of several cases of kidney cysts before birth but it has always affected both kidney's not just the one. If it is only one does that mean the second kidney is developing and working normally? If so then although it is a big concern there are a number of people who are only born with one kidney or loose one for a number of reasons and lead completely normal lives with no consequences to having only the one. And that would be looking at the worst case scenario of loosing that kidney. If there is just a blockage then they can dilate the tube to improve its functioning. I guess its on of those things you wont know the severity of until after bub is born and they look at urine function and do further scans.

DS1 had polycystic kidney disease, but that is an extreme of possible kidney problems. Renal issues are very common and if it's just one kidney, then it is less of a concern. Questions I'd be asking include, has this affected the development of amniotic fluid and therefore the lungs? Should I have steroid shots to help baby's lung development? Is the liver affected?

Otherwise, it's a wait and see situation.

My DS has a congenitally absent kidney. In a hurry, but will be back with more!

Just spoke to SIL and she said this
" I am guessing we won't know the severity until this next scan but in the original 29 week ultrasound it said noticeable cyst in left kidney and something about a PUJ obstruction and something to do with the renal tube?? His right kidney is functioning perfectly normal but the left has a cyst caused from a PUJ obstruction."

Hi Starrysky, your SIL is right, you won't know the entire extent of the problem until her baby is delivered. The placenta does the function of the kidney's in utero so it is difficult to determine if and how well a compromised kidney will function before birth.

Firstly, the fact that the right kidney is of normal structure and has a normal blood supply and fluid flow is an excellent sign. Depending on what study you read, between 1 in 500 and 1 in 2500 live births are of a baby with a single kidney. If that single kidney functions normally, the patient should go on to have a normal life.

The PUJ refers to the (renal) pelvis-ureter junction. The bottom of the kidney is where the urine pools once it has been formed by filtration of the glomerulus (say that fast 10 times!!), this area is known as the renal pelvis. The urine then drains by the ureter (a tube) to the bladder where it waits to be passed by the urethra (another tube!). In normal anatomy, each person has two kidneys, two ureters, one bladder and one urethra. From the information you have, your niece/nephew has an obstruction in the left kidney at that point where the renal pelvis meets the ureter. This obstruction may caused by the cyst itself or it may be an obstruction due to a separate cause, the urologist will be able to tell your SIL. S/he will also be able to tell your sister whether the obstruction is complete or partial, meaning whether any fluid at all is able to pass through the ureter on the left side.

It is my understanding that if the kidney were to be reabsorbed by the baby, this would have occurred in the first trimester. I don't think that the kidney can be reabsorbed at 30 weeks gestation, but again your SIL should check with the urologist!

There are several treatments for a PUJ obstruction; if the obstruction is very minor (it sounds like this might not be the case) it may simply be monitored and the kidney function may improve with growth, the surgeon can try to dilate the ureter to increase the lumen (the internal size of the tube), the blockage can be cut out and the ureter reattached, or sometimes the kidney function is too compromised and the kidney is damaged so it must be removed.

Life with one functioning kidney is not much different to that of someone with two - we are very careful of infection (my DS has complications of his existing kidney which make infection far more likely) and my DS was circumcised on the very strong advice of his urologist as UTI's are much, much less common in a male infant who has been circumcised. Contact sports are another area we are very careful. I am happy for my DS to kick a footy around with his mates and have a play wrestle, but I encourage him to play non contact sports for recreation. There are quite a few professional AFL players who have lost a kidney due to on field incidents! Lowering the risk of diabetes is an ongoing concern, so we encourage a healthy diet and one which is low in sodium. As he gets older, my DS will have to be careful not to develop hypertension (high blood pressure) as the hypertension itself may damage the kidney and may also be a sign that his kidney is failing. DS will need to be a careful alcohol consumer when the time comes. We are very conscious of the fact that DS only has a single kidney, but it really doesn't affect his day to day life. He is almost 8 now, and he is pretty aware of making good choices.

Feel free to ask any more questions, and I'll answer them if I can. Of course, the best person for your SIL to speak to is a paediatric urologist. I know a fantastic one if she happens to be in Melbourne!

Hugs to both of you. :hug:

Hi Starrysky, just wondering how your SIL is going? Not long until her next scan, I hope she gets some good news!

Thank you so much for the info Nickle730, I sent my SIL the link so she could have a read, she was very happy with that. (well, gives her some peace of mind anyway)
we are definitely hoping it will be good news on Thursday :)

Hi Starrysky, how did your SIL's scan go?

It went well from what I've heard, the US place didnt tell them anything, but their appt with the specialist was on Friday.
message from SIL:

"Apparently it's only a small objection in his renal tube and she basically said it can go either way it might fix itself or it might need surgery. When he is born he will go on antibiotics to prevent a UTI and they will ultrasound him to see what needs to be done, I am hoping it goes away on its own I am pretty optimistic it will all be okay"

That's great news, Starrysky! Your SIL sounds like she is coping well, I look forward to hearing of the arrival of a beautiful healthy baby in a couple of months :)