To nephrectomy or not to nephrectomy?

Re: To nephrectomy or not to nephrectomy?

Anthony Dennison — Wed, 18 Dec 2013 13:01:49 GMT

I had a cat with kidney disease present last month, sounded like acute signs so it was admitted for a scan and fluids - I though it was renal calculi with secondary hydronephrosis, so referred it for a nephrectomy rather than doing it in house. Glad I did - turned out it was actually advanced renal lymphoma, and there were pulmonary changes too.

Something to keep on the differentials list

Re: To nephrectomy or not to nephrectomy?

Martin Atkinson — Tue, 17 Dec 2013 11:47:56 GMT

I had a dog which presented with haematuria as its primary symptom. It also had a palpable sub-lumbar mass which was investigated/biopsied and investigation of the kidneys at the same time revealed miliary white spots all over both of them. I assumed these were secondaries from the larger mass and chickened out of biopsying these. The histology from the mass showed lymphosarcoma of the sub-lumbar lymph nodes (there was no evidence of involvement of blood or any other nodes or organs). The dog was treated with modified Madison protocol, the sub-lumbar mass and the haematuria resolved and is he still alive 4 years later and counting.

The moral here is look for other organ/tissue involvement and if you don't think your echogenic lesion in the kidney is a urolith - are you brave enough to do a kidney biopsy?

Re: To nephrectomy or not to nephrectomy?

Hannah Wynne Richards — Mon, 16 Dec 2013 22:27:51 GMT

I'll second Kate. These sound like the type of owners who will do the rounds until they find a veterinary surgeon who agrees with them.

Wynne

Re: To nephrectomy or not to nephrectomy?

Hannah Wynne Richards — Mon, 16 Dec 2013 22:27:41 GMT

I'll second Kate. These sound like the type of owners who will do the rounds until they find a veterinary surgeon who agrees with them.

Wynne

Re: To nephrectomy or not to nephrectomy?

Kate Richardson — Sat, 14 Dec 2013 21:00:00 GMT

I know it may be out of your hands now, but I seriously hope they don't rush into a nephrectomy without some seriously good evidence that it is necessary! You may not have given the client what they wanted, but your conscience will sleep easy! So important to understand that ultrasound does not give a diagnosis in most cases, unless followed by fnas or biopsy, which surely the clinical notes would have noted if had been done....

Re: To nephrectomy or not to nephrectomy?

Tim Charlesworth — Sat, 14 Dec 2013 19:18:33 GMT

oops yes, sorry, typo! SUB is basically a nephrostomy tube connected via an injection port to a cystostomy tube so yes drains urine from renal pelvis to bladder.The injection port allows regular flushing or sampling (of urine from that one kidney).

Nothing to do with the liver!

Re: To nephrectomy or not to nephrectomy?

Hannah Wynne Richards — Sat, 14 Dec 2013 11:06:10 GMT

Now I know.

Wynne

Re: To nephrectomy or not to nephrectomy?

Andrew Kent — Sat, 14 Dec 2013 10:58:45 GMT

The SUB is a subcutaneous ureteral bypass - it's basically a tube that replaces the ureteral travelling from the kidney to the bladder (I think mention of liver was a typo by Tim). Some people use them for ureteral diseases especially if stents can't be placed for any reason.

difficult to judge the kidney on those images but maybe a small cyst? Certainly wouldn't be in a rush to remove it based on that may just be an incidental finding!

Re: To nephrectomy or not to nephrectomy?

Hannah Wynne Richards — Sat, 14 Dec 2013 09:50:14 GMT

Francisco. Glad I'm not the only one!

I once heard a tale (possibly apocryphal) about a certain university lecturer who was notorious for launching into strings of initials during his lectures - without 1st bothering to explain to students what they meant. Anyway, come the Christmas revue (topical ) they decided to get their own back. A student stood in front of the theatre declaiming a long list of random initials, with an occasional and or the or but inserted, and ended up with a rather naughty suggestion about Sand M and PVC. Unfortunately, the joke fell as flat as a lead ballon- the entire audience had switched off!!!!!!!!!!!

Wynne

Re: To nephrectomy or not to nephrectomy?

bob lehner — Sat, 14 Dec 2013 09:39:27 GMT

I was born with a congenital hydronephrosis in the left kidney (renal vein wrapped round the ureter causing an obstructiion).

No problem at all until I went to university and started to drink lots of beer - leading to excruciating renal colic.

This was long before ultrasound and my problem was diagnosed via i.v.u. (or strictly i.v.p. - intra-venous pyelogram). They also stuck some radioactive stuff into my blood and measured how much went through each kidney to assess individual renal function.

i.v.u is a very simple technique to do and you can easily get good pictures of a cat's kidneys - remember to starve it beforehand and give it a really good enema first to clear out the g.i. tract, which otherwise may obscure your view.

Nowadays I just scan my own kidney from time to time to keep an eye on the big black hole there - (my main concern is the huge amounts of radiation I received as a result of numerous i.v.u. exams over the years -each one involved multiple exposures as I recall).

Re: To nephrectomy or not to nephrectomy?

Francisco Gomez — Sat, 14 Dec 2013 09:36:18 GMT

I ain't laughing, I don't know that one either

Re: To nephrectomy or not to nephrectomy?

Hannah Wynne Richards — Sat, 14 Dec 2013 09:34:53 GMT

Tim Assuming no-one actually implants submarines in animals abdomens - what on earth is SUB?

Wynne

Hope the remaining 10,000 + of you aren't laughing, because (of course ) you ALL know what SUB means

Re: To nephrectomy or not to nephrectomy?

Francisco Gomez — Sat, 14 Dec 2013 09:28:39 GMT

That looks like a normal left kidney to me? Depending on what plane u are 'ultrasounding'? Perhaps from my iphone the image is not that clear...

Re: To nephrectomy or not to nephrectomy?

John Flynn — Sat, 14 Dec 2013 04:22:48 GMT

Thanks, Tim, for your contribution.

I'm based in Ireland and have never had a mobile ultrasound specialist visit - I suspect this is possible, but probably I'd need to stump up more than 1 case as the closest one I've found (google!) would be a 6 hour round trip for the day and once equipment and expertise costs are factored in I'd guess such a move would be cost-prohibitive - referral to Dublin would be a more practical option (but never popular with owners).

Not much else to add from speaking to previous vets. Effectively much as per info I already presented.

Did manage to get ultrasound images emailed though (I believe these are both of the same "diseased" kidney, but I could have misunderstood):

http://www.vetsurgeon.org/members/Jazz/files/Kidney+scan+frames/kidney1.JPG.aspx

http://www.vetsurgeon.org/members/Jazz/files/Kidney+scan+frames/kidney2.JPG.aspx

It's become a little academic as the client was clearly not too impressed with me (first impressions count!) and when I rang to discuss (OK a day or 2 later than I'd intended...), mumbled an apology about having taken the cat to another vet. My plan had been to suggest further investigation or just monitoring the situation clinically as I felt either option would be superior to removing a kidney in haste to perhaps repent at leisure.

So thanks for everyone's advice, but I'm afraid I don't reckon there'll be much follow-up on this one.

I'd be interested to know what folk think of the still ultrasound images - I found them of decent resolution but diagnostically unconvincing, but then scanning kidneys is hardly my forte.

PS - Tim, I've been trying to figure in my head how the "SUB" thing works - is this a synthetic pipe plumbed into the renal pelvis and then into the gall bladder?? Is this a well-established technique with documented superiority to nephrotomy for renolith removal or is it still in the experimental phase or is it just that the indications would be different?

Re: To nephrectomy or not to nephrectomy?

Tim Charlesworth — Wed, 11 Dec 2013 11:08:13 GMT

I completely agree with the other posts and would advise caution. If you haven't done so already it would be worth doing full urinalysis including a sediment exam looking for microscopic crystalluria and checking urine pH. If there is a stone in the kidney (if you're lucky and its radiopaque it may show up on a lateral rad) then it may just sit there causing intermittent H+ but if you can ID the likely type then you could try dissolving it with the appropriate diet. If the stone was causing proximal ureteric obstruction (and you would seen some evidence of hydronephrosis/hyodroureter on scan) then you could consider nephrotomy to remove rather than nephrectomy (the current trendy surgery is to place a "SUB" bypass shunt from the kidney to the liver to allow the kidney to drain past any uroliths).

Overall though, too many "unknowns" to do a nephrectomy just yet. Providing the cat is stable (PCV etc) then no rush. There are quite a few imaging specialists who will travel from practice to practice (with their own scanners) and they may be able to visit you and scan the cat for you? If you tell me where you're based I'll see if I can find one for you if you think the owner would go for it (I appreciate its more money but would be cheaper than nephrectomy!).

Hope this helps,

Tim

Re: To nephrectomy or not to nephrectomy?

Robin Grimmer — Tue, 10 Dec 2013 23:03:36 GMT

If it's upper renal tract disease ie true IRH - then the only sign should be haematuria and possibly anaemia if enough blood loss. If it's lower urinary tract disease ie FLUTD then you would expect signs of dysuria, pollakiuria and possibly stranguria. This might help localise the problem.

Re: To nephrectomy or not to nephrectomy?

Andrew Kent — Tue, 10 Dec 2013 22:57:20 GMT

You can measure total GFR using iohexol clearance, it's not that difficult to do, you give iohexol then take a few blood samples at set periods later. It would give you a figure that could be compared to normal, the problem being that normal doesn't require completely normal kidneys, as a big functional reserve. And it doesn't tell you how much each kidney is contributing, so you could still remove one and be caught out. I can't remember which lab it gets sent to but can check if you need to do it. It may be one that has to be sent to the US.

we tend to find that renal lesions are very non-specific and so frequently adopt a monitoring approach if we find them.

interesting case though!

Andy

Re: To nephrectomy or not to nephrectomy?

KathW — Tue, 10 Dec 2013 22:43:06 GMT

What about getting full urinalysis including microscopy and cytology done on a urine sample - unless that has already been done. Won't help with the question of kidney function but may help to give some clues as to whether anything else is going on ?

Re: To nephrectomy or not to nephrectomy?

Mark Holmes — Tue, 10 Dec 2013 22:25:09 GMT

I had a similar case a few years ago, which turned out to have a renal abscess. I found it with the ultrasound and took an FNA. - I neohrectomised that cat which did really well - until it got one in the other side. Not sure if that supports surgery or not, but the ultrasound and FNA were a doddle.

Re: To nephrectomy or not to nephrectomy?

John Flynn — Tue, 10 Dec 2013 21:53:47 GMT

[quote user="Andrew Kent"]Hi John,

There is no way of determining how much each kidney is contributing to GFR. IVU would tell you if one kidney is not working but is unlikely to tell you much more than that.

in cats renal haematuria is difficult to determine, in a dog I would do cystoscope and look for blood coming down the ureter. In a cat you could do a laparoscopic assisted cystoscopy but may need to surgically explore the bladder. And in cats that can be difficult as the ureter opens in the proximal urethra.

many people have gone off the idea of nephrectomy in idiopathic renal haematuria because the other kidney often starts bleeding which means it was then pointless. However if there is a lesion on the kidney this may not be idiopathic. Personally I would probably monitor this kidney lesion with ultrasound and see if it is changing. If it is them perhaps FNA or biopsy the kidney. In idiopathic renal haematuria and ACEi may help by reducing glomerular pressures but again I'm not convinced of the diagnosis.

I agree with others that FLUTD is a much more common disease and so seems much more likely.

Andy

[/quote]

Thanks, Andy. That's really interesting. I didn't even know idiopathic renal haematuria was a condition or that nephrectomy was ever recommended for this, so I've learned a lot already!

You say there is no way of determining how much each kidney is contributing to GFR, but, theoretically, is there any point in testing the GFR to see if it is above a certain threshold and if so how would one go about that? Does one test GFR prior to removing a kidney from a donor cat in USA for instance? What would be the most sensitive means of assessing GFR, even if this couldn't assure adequate function of the remaining kidney, to pick up on a lack of GFR that would be a clear contraindication to nephrectomy?

Re: To nephrectomy or not to nephrectomy?

John Flynn — Tue, 10 Dec 2013 21:43:58 GMT

[quote user="Evelyn Barbour-Hill"]Hey, you can be the hero vet who discovered it didn't need a kidney removed![/quote]

I can, I'm just not 100% sure yet that I'll be able to ascertain this with certainty? And judging by the albeit brief encounter I've had with the cat's current/future carer [the client to me], I sense a certain lack of trust in my judgement compared to the previous vet (which is strange, as I don't figure the client actually ever visited the previous vets, but perhaps they had heard good things?!)

I'm good with ending up the hero, just a slight nervousness that I could end up arch-villain if my skeptical nature means I refuse a plan of action to a client who may be exacerbated with this in spite of my best explanations and then I end up proven wrong somehow... but it appears I'm in pretty good company with my skeptical interpretation of the info presented to date, so am more confident that won't be reaching for a scalpel blade without a bit more reasoning somewhere along the way

I'll let you all know what the former vets have to say when I phone them tomorrow (if I can get a hold of anyone who knows anything beyond reading out the faxed clinical notes).

Re: To nephrectomy or not to nephrectomy?

John Flynn — Tue, 10 Dec 2013 21:30:38 GMT

[quote user="Mark Hedberg"]Also, i'd be extremely wary of ultrasound diagnosis[/quote]

Me too! (But then that's mainly because I'm looking at my own ultrasound diagnoses where I generally use a piece of equipment to help me imagine in grey dots whatever it was I expected to see in the first place, and sometimes like those infernal magic eye pictures I just can't see it... )

That said, I've inherited a couple of dodgy ultrasound diagnoses before where "masses" and "tumours" have led to grave prognoses that surprisingly never materialised much to everyone's relief.

On the diagnostic front, though, I have a funny feeling that the vet(s) with the ultrasound diagnosis in this case is/are probably decidedly more familiar with that dark-art than I am and I'd be wary of ignoring their findings purely based on me not finding a similar finding should I ultrasound the offending kidney (if that makes sense). I've not seen many bleeding renal masses before, but then have I looked? I don't normally make a diagnosis that I'm not already thinking of, and I wouldn't have been thinking of this from what I read of the cat's history; I guess it would be bad also if I decline to do the procedure and it later emerges the cat has metastasis from a tumour in its renal pelvis (not that I would likely know that was the outcome, and I'm not even sure if that is a possibility or not)?

I could be overthinking this, but I do slightly worry that I could be risking ignoring a perfectly decent clinical course of action that just seems a bit alien to me based purely on my lack of trust in the plan of more than 1 professional colleague more familiar with both the case and the original owner (and therefore original history of presenting signs which I can't really get firsthand anymore) and, based on their clinic's website, almost certainly better equipped with modern diagnostic facilities than I am.

...and that's why this site is so useful for canvassing a wider audience as to what they would do!

Re: To nephrectomy or not to nephrectomy?

Andrew Kent — Tue, 10 Dec 2013 21:22:47 GMT

Hi John,

There is no way of determining how much each kidney is contributing to GFR. IVU would tell you if one kidney is not working but is unlikely to tell you much more than that.

I agree with others that FLUTD is a much more common disease and so seems much more likely.

Andy

Re: To nephrectomy or not to nephrectomy?

Evelyn Barbour-Hill — Tue, 10 Dec 2013 21:21:14 GMT

[quote user="John Flynn"]I'd also wondered about intravenous urogram??[/quote]

Exactly what I was about to suggest. It gives better – well different – information, so it can't possibly be wasted, can it?

[quote user="John Flynn"] the client (who pretty much came in explaining the cat needed a kidney removed) [/quote]

Hey, you can be the hero vet who discovered it didn't need a kidney removed!

Re: To nephrectomy or not to nephrectomy?

John Flynn — Tue, 10 Dec 2013 20:06:58 GMT

Thanks, Fran - all advice gratefully received! (and good luck with your certificate studies )

I agree that the urine SG might be a good place to start (if this was done at the previous clinic, then it was not recorded in the notes I received). But even if I get repeated samples and find one over e.g. 1.045 then I'm still not sure that's enough to convince me that the cat will be fine with just one kidney? (or live as long as it might have without such intervention and removal of blood filtering capacity as you say, but then I know cat's CAN live with one kidney, so wondered if I was just being woosey about this)

I'd also wondered about intravenous urogram?? [got to be a decade since I did this, at least, and I'm guessing has largely been replaced by ultrasound?]

I more listened to the client (who pretty much came in explaining the cat needed a kidney removed) than anything, so haven't suggested further investigations yet (I bought myself some time by saying I'd best chat to the previous vets - I'm posting here to get some ideas prior to that conversation as I don't want to sound silly by questioning their course of action, especially as sometimes these things turn out to sound a lot clearer than they did initially).