Kidney disease in young cat

Re: Kidney disease in young cat

Christopher Saul — Thu, 27 Jan 2011 00:05:19 GMT

I've only just seen this thread just now and it's very interesting; extremely good work up so far Morna! I don't feel I can add an awful lot except to say I'd agree with Kate's sentiments .....

The only things I might bring up at this stage is that the kidneys felt irregular/nodular on palpation but you don't mention seeing any such gross nodules on ultrasound. I suppose it might be the case that the kidneys are not evenly affected and so you may have been unlucky with your FNAs and not got a representative sample; thus there may be an arguement for biopsy here, as long as the owners are made aware of the risks ( both with regards to the surgery and that there's no guarentee that the results will alter case management)

Of course, I'm supposing you've already excluded septic foci elsewhere ( done a full haematology/smear and done good imaging of the rest of the abdo etc.......

Chris

Re: Kidney disease in young cat

Kate Richardson — Wed, 26 Jan 2011 18:02:53 GMT

Please let us know the results when you get them. Glad he is doing ok.

Re: Kidney disease in young cat

morna — Wed, 26 Jan 2011 17:56:22 GMT

Thanks for all the advice. After discussion with the owners we have decided to to perform a kidney biopsy. Have started on renalzin and will give B12 next time he visits.

Kate - there were a very small number of struvite cystals in a free catch sample analysed in-house, the external lab found no crystals and some blood (cysto sample) and culture was negative.

There has been no deterioration reported by the owners in the last week. We are currently testing the entire spectrum of renal diets available. He's due for a check-up this week so will see if fortekor has made any difference to blood pressure and discuss possibility of subcut fluids at home.

Thanks again,

Morna

Re: Kidney disease in young cat

Martin Atkinson — Thu, 20 Jan 2011 09:12:29 GMT

[quote user="Richard Fox"]

Acutally Martin that raises the point of the advantages of ex-lap - you can see things that (unless you do Laparoscopic surgery) you would not have picked up doing percutanous FNA or bx - you can have a jolly good look around!

[/quote]

Absolutely. Except in exceptional circumstances performing an ex. lap. is safe and quick, more reliable and in real terms cheaper than ultrasound guided biopsy. It maybe that its because I'm 'old school' and don't possess the equipment to do otherwise but I am still convinced that it is the best way forward in diagnosis of conditions involving the abdomen and if the condtion requires a surgical remedy you're already half way there. Plus for interstinal biopsies it is the only way to get a full thickness sample which will be more diagnostic than endoscopic pinch biopsies.

Re: Kidney disease in young cat

Richard Fox — Wed, 19 Jan 2011 19:20:29 GMT

Re: Kidney disease in young cat

Martin Atkinson — Wed, 19 Jan 2011 17:15:37 GMT

I had a CKCS with lymphoma of the sub-lumbar nodes with no other apparent lymphatic involvment. The only symptom was haematuria and a mass palpable per rectum. I did a diagnostic biopsy of the lymph nodes at ex lap and noted multiple ~ 1mm diameter white lesions in the visible parenchyma of the kidneys, but no-where else, which I didn't biopsy on the assumption it was related (with note of previous comments: the thought of a wedge biopsy on a kidney fills me with fear - liver, pancreas, spleen, intestines OK - not kidneys given you'd have to cut down to the pelvis to get a fully representative sample - does anyone do that?!). Whether the primary lesion was sub-lumbar or renal I couldn't say but the dog was given a modified Madison chemo. protocol and is still alive and asymptomatic 3 years later albeit rather overweight because I never had the courage to stop the preds!!

Re: Kidney disease in young cat

Kate Richardson — Wed, 19 Jan 2011 17:06:30 GMT

Agreed!

Re: Kidney disease in young cat

Richard Fox — Wed, 19 Jan 2011 16:48:21 GMT

[quote] multiple FNAs could give you an idea about whether any pathology existed, helping you then make a decision as to whether histo would be more useful or not. [/quote]

I would agree with that However (not being condescending) one should remember that raised liver and renal parameters do not necessarily mean primary renal or hepatic disease is present as can be seen from the previous posts - I do believe in non-invasive test first and imaging then correlating this with the disease before invasive procedures like FNA, tru cut or larger biopsies (sorry granny sucking eggs )

And to every bodies relief I now dismount my soap box

Re: Kidney disease in young cat

trevor whitbread — Wed, 19 Jan 2011 16:42:26 GMT

If concidering safety fna may be marginally safer than trucuts, although serious complications with trucuts or wedge biopsies are now rare. FNA will give you the information you want in probably less than half of your cases and then you will need histo anyway . FNA can be very useful but you must know what questions you are asking . It should not be used as a screening tool . In renal disease glomerulopathies , amyloid , tubular degeneration and interstitial fibrosis canot be diagnosed with cytology Neoplasia , severe inflamation such as fip can . Similarly it is of limitted value in liver disease especially if a diagnosis/prognosis depends on small changes or architectural features which is often the case . Cytology is a useful tool but not a replacement for histo , tempting though that may seem

Re: Kidney disease in young cat

Kate Richardson — Wed, 19 Jan 2011 16:41:36 GMT

No, not coming across as argumentative! I probably come across that way when I am passionate about a subject too! It's good to hear lots of opinions as you can then make informed choices about investigative procedures. Thinking back to the CPD, it may have been more that multiple FNAs could give you an idea about whether any pathology existed, helping you then make a decision as to whether histo would be more useful or not.

Re: Kidney disease in young cat

Richard Fox — Wed, 19 Jan 2011 16:01:40 GMT

[quote]Recent CPD on liver disease suggested that multiple liver FNAs may be preferable to a liver biopsy for the same reason.[/quote]

Architecture cannot be assessed cytologically - I do not recommend using cyto as a replacement for histo! I agree that a lot of trucut biopsies are not great as they have limited info on architecture but a damn site more than cytology. If you get inflammation in a cyto do you know where it is? If you get some lymphoid cells do you know where they are, if you get some atypical hepatocytes do you know how they are arranged?

Cytology is a fair screening test esp for neoplasia but for many instances it is a poor assessment of liver disease and pretty awful assessment of renal disease.

BTW I do both histo and cytology and therefore I am not biased . They both have their role but I do so many histo cases and histo with cyto together and you would not believe the differences you get between the 2 samples. These methods are not commonly used in human medicine to my knowledge?

I'm sorry if I come across as a bit argumentative but I feel passionate about this subject !

Re: Kidney disease in young cat

Kate Richardson — Wed, 19 Jan 2011 14:07:03 GMT

I think that unless there are obvious renal masses/changes on ultrasound to guide you then you could miss any pathology with a biopsy, just as you could with an FNA but would be safer to do multiple FNAs compared to multiple biopsies. Recent CPD on liver disease suggested that multiple liver FNAs may be preferable to a liver biopsy for the same reason.

EPO definitely something else to consider if, as Martin says, PCV drops lower and starts affecting cat clinically.

Personally I use 160-180mmHg as borderline hypertenstive, and 180mmHg+ as hypertensive especially if I have a disease which I know can cause hypertension. If it was a well cat having a routine BP check with no signs of hypertensive injuries and no obvious signs of any diseases that may cause hypertension, I would recheck the BP a couple of weeks later. At 180mmHg I would start amlodipine though at the low dose 1/8 of a tablet daily.

Re: Kidney disease in young cat

Richard Fox — Wed, 19 Jan 2011 11:31:38 GMT

TBH renal lymphoma is one of the only diseases to cause significant (I mean big) renomegally unless you have hydronephrosis etc. So if they are only mildly enlarged and not progressive then lymphoma prob not likely - I think cyto is fairly sensitive but only if the aspirates are of good harvest and quality i.e. should be at least some renal epithelial cells etc but +++ monomorphic lymphocytes are highly suggestive as intersitital nephritis ususally gives rise to mixed lymphocytes and plasma cells usually.

Re: Kidney disease in young cat

Martin Atkinson — Wed, 19 Jan 2011 11:12:59 GMT

I broadly agree with the consensus on this, but how happy can you be with the renal FNA ruling out lymphoma? - I guess biopsy would be useful to be certain about that and justified in such a young cat as it is probably the only condition other than urolithiasis that would alter standard management of CRF. BP of 180 is borderline hypertensive so Fortekor should be fine and I would be giving that for the renal disease alone, don't think there's any need for amlodypine yet. I would consider EPO for the anaemia if HCT drops any lower and think about a skin button for S/C fluid administration if the renal failure is progressive.

Re: Kidney disease in young cat

Richard Carter — Wed, 19 Jan 2011 10:50:08 GMT

Doing well, putting on weight, not done follow up blds but as I was taught that in general a BUN/creat of 3x n was extremely poor prognosis in a cat producing urine and basically put the cat in a box, I am very glad the owner wanted to persist. Do obviously treat the patient, not the lab machine but will have to look at some of the other 'azotaemic' cases (and not listen too closely to other people's experience!!).

Re: Kidney disease in young cat

Kate Richardson — Wed, 19 Jan 2011 09:34:59 GMT

Richard, have you done any follow up bloods urine now that the cat (I assume) is back home and clinically normal? Wonder whether it had pre-existing subclinical renal disease prior to the FB, making it much more likely to develop severe dehydration/azotaemia, or as you suggest maybe some toxin causing an element of acute renal failure?

Re: Kidney disease in young cat

Richard Carter — Wed, 19 Jan 2011 00:38:26 GMT

[quote user="Kate Richardson"]renal damage/prognosis until rehydrated and reassessed. It just confirms that you cannot make a diagnosis of renal disease based on bloods alone. Out of interest what was the USG in that case? [/quote]

While receiving shock rehydration bld urea 39mmol/l; creat 356umol/l; phos 3.61 urine SG 1.032, pH5.5, prot 2+, bld 2+ (cysto sample), sediment mucinous debris.

2 days later fully rehydrated but intestine in state of paralytic ileus urea 45.3, creat 490 but phos had returned to n values. By now drinking well, urinating well.

Toxins in rubber??

Re: Kidney disease in young cat

Richard Fox — Tue, 18 Jan 2011 15:33:19 GMT

[quote user="Kate Richardson"]

[quote} I've never done one or seen one, so that's useful to know and in the right hands, probably is safe enough, but not sure I would want to attempt it. In most of the cases I have seen where I have considered a renal biopsy, after speaking to specialists, the feeling was it was very unlikely to change our treatment plan, but am sure there may be some cases where it might. In cases where ultrasound has suggested renal neoplasia, fnas were enough to get a diagnosis. I guess its like any investigative procedure, you have to weigh up the benefits versus the risk.

[/quote]

+1 - Not sure that the bx will give you any evidence to change you treatment regimen ?

Re: Kidney disease in young cat

Kate Richardson — Tue, 18 Jan 2011 14:43:50 GMT

[quote user="Michael Woodhouse"]as a student at the RCV I saw them do a couple in cats; prep skin and a bleb of local. As far as I know they weren't sedated and definitely not under general anaesthetic. With ultrasonic guidance and avoiding blood vessels ect they thought it was quite a safe procedure. [/quote]

I've never done one or seen one, so that's useful to know and in the right hands, probably is safe enough, but not sure I would want to attempt it. In most of the cases I have seen where I have considered a renal biopsy, after speaking to specialists, the feeling was it was very unlikely to change our treatment plan, but am sure there may be some cases where it might. In cases where ultrasound has suggested renal neoplasia, fnas were enough to get a diagnosis. I guess its like any investigative procedure, you have to weigh up the benefits versus the risk.

Re: Kidney disease in young cat

Rob Loxley — Tue, 18 Jan 2011 13:46:48 GMT

[quote user="Kate Richardson"]You can always add phosphate binders as you have said, although I find the 'palatable' ones don't seem to be that palatable to cats! Anyone got any preferences with phos binders in cats? [/quote]

Cats being fussy so-and-sos I always start with a tiny bit and then increase to the dose needed. Eg. with Ipakitine start with a pinch and then gradually increase. YMMV

Re: Kidney disease in young cat

Michael Woodhouse — Tue, 18 Jan 2011 13:35:14 GMT

[quote user="Kate Richardson"]A kidney biopsy may give you a definitive diagnosis (or it may not) but will probably not change how you manage this case and there are significant risks associated the procedure, incl the ga effects/post op pain/effects on appetite as well as the risks of haemorrhage etc.[/quote]

I have never done a kidney biopsy myself but as a student at the RCV I saw them do a couple in cats; prep skin and a bleb of local. As far as I know they weren't sedated and definitely not under general anaesthetic. With ultrasonic guidance and avoiding blood vessels ect they thought it was quite a safe procedure.

Just like they do liver biopsy on horses.

Re: Kidney disease in young cat

Kate Richardson — Tue, 18 Jan 2011 12:49:21 GMT

But Richard, your cat was clinically severely dehydrated, so I wouldn't make any judgments on renal damage/prognosis until rehydrated and reassessed. It just confirms that you cannot make a diagnosis of renal disease based on bloods alone. Out of interest what was the USG in that case?

In Morna's case the cat presented as a well cat with polydipsia, with an azotaemia and dilute urine. Very different situation.

Re: Kidney disease in young cat

Richard Carter — Tue, 18 Jan 2011 12:14:50 GMT

Just had a young cat post xmas that had eaten a rubber something. He however presented severely dehydrated with both urea and creat at top end of vettest scale but with urine sediment basically normal we went looking for something else. Xray showed gas in intestine (no f/b visible of course) so after giving the worst prognosis, ex lap to find ? f/b - cat doing fine now so now less impressed with urea/ creat as indicator of renal damage/prognosis.

Re: Kidney disease in young cat

Kate Richardson — Tue, 18 Jan 2011 10:09:47 GMT

Sounds like you have done a really thorough work up. A kidney biopsy may give you a definitive diagnosis (or it may not) but will probably not change how you manage this case and there are significant risks associated the procedure, incl the ga effects/post op pain/effects on appetite as well as the risks of haemorrhage etc. My feeling would be to not to do a biopsy, but concentrate on managing the renal disease, but would welcome comments on this from other medics? In my experience, young cats that develop renal failure do poorly compared to older cats; they tend to deteriorate much more quickly.

What crystals did you see on urine sediment exam? Were they seen on immediate examination by yourself in house or by the lab- ie are they 'real'? Worth being absolutely sure no ureteroliths- really good radiographs can sometimes pick them up esp on a DV view. Ultrasonography may reveal mildly dilated ureters as well if this is the case but probably needs an experienced ultrasonographer- not sure I would confident in detecting them yet unless moderately to markedly dilated. I assume both kidneys had a similar appearance on scan?

I would also give a course of broad spec antibiotics eg amoxyclav in case of an occult pyelonephritis. Was the urine a free catch or cysto? If cysto could that explain the blood?

Management wise, would use amlodipine to control hypertension, fortekor has minimal effects. UPC of 0.2 in a cat is borderline for proteinuria so I would continue the fortekor. I agree, glomerulonephritis I would expect more protein, but wouldn't rule it out. EFAs can be helpful in glomerulonephritis and won't do any harm. Diet wise, ideal if he will eat renal diets happily, lots of different ones available so try lots, I find cats seem to prefer the dry kd or the Royal Canin renal sachets (3 flavours as well!) Hills g/d is another option I think if he won't touch k/d. But if he really doesn't want to eat them, then I always feel it is better that he eats what he likes than picks at something he doesn't, it may be all about quality of life from this point onwards unfortunately. You can always add phosphate binders as you have said, although I find the 'palatable' ones don't seem to be that palatable to cats! Anyone got any preferences with phos binders in cats?

Have you checked potassium levels- common cause of inappetance in cats, and common finding in renal cats, if low supplementing either orally or iv may make a huge difference. Plus B12 supplementation. Also consider anti-nausea meds and ant-acids if he still won't eat and then appetite stimulants. I like mirtazipine to get them going sometimes if all else fails but only short term, and am seeing occasional neuro side effects with it more commonly now.

And most importantly fluids, fluids, fluids- iv if nec, sc otherwise, as often as cat needs. If owners are that dedicated and cat is amenable, sc fluids at home are great. See FAB website owner info for guidance- great to print out for owners.

Hope that helps

Kate