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tunic
November 30th 04, 09:38 PM
hello,

my cat (male, 3.5 years old) had urethra blockage twice before (in a 1.5
year period) due to struvite crystal formation in his bladder
he has been on a specific diet (hills c/d) which is a low-magnesium
acidifying food in order for the crystals to be dissolved. he was also fed
another acidifying medicine (named methygel)

yesterday he had another blockage, i took him to the vet and he has been
catheterized. the vet took urine samples and measured the pH which was
very acidic (6) and checked them at the microscope but couldnt definitely
determine if the crystals were sturvite or calcium ocalate. one logical
explanation is that the acidifying diet aimed at struvite crystals made
way for the formation calcium oxalate ones. but the clues tend to
sturvite..

my questions are:
1. is it possible for sturvite to be formed in such an acidic environment
(pH = 6)?
(though today, after being fed a normal food, the pH was 8.5!)

2. how easy is it to determine wether it's struvite or calcium oxalate? in
the microscope there can be seen a variety of shapes and forms of crystals
(but not a great number of them). is there another more accurate method?


any help would be valuable
thank you

Phil P.
December 7th 04, 02:51 PM
"tunic" > wrote in message
lkaboutpets.com...
> hello,
>
> my cat (male, 3.5 years old) had urethra blockage twice before (in a 1.5
> year period) due to struvite crystal formation in his bladder
> he has been on a specific diet (hills c/d) which is a low-magnesium
> acidifying food in order for the crystals to be dissolved. he was also fed
> another acidifying medicine (named methygel)
>
> yesterday he had another blockage, i took him to the vet and he has been
> catheterized. the vet took urine samples and measured the pH which was
> very acidic (6) and checked them at the microscope but couldnt definitely
> determine if the crystals were sturvite or calcium ocalate. one logical
> explanation is that the acidifying diet aimed at struvite crystals made
> way for the formation calcium oxalate ones. but the clues tend to
> sturvite..
>
> my questions are:
> 1. is it possible for sturvite to be formed in such an acidic environment
> (pH = 6)?
> (though today, after being fed a normal food, the pH was 8.5!)

Whenever you find crystals in acid urine it means that either the urine is
not sufficiently acidified or insufficient time has elapsed for the crystals
to dissolve. If urine pH is high for any length of time crystals can form.

Also, a single determination of acidic urine does not mean the urine was
sufficiently acidic to be undersaturated with struvite before the
obstruction --- the fact that you found crystals proves it wasn't.

Another thing to remember is anorexia usually develops after cats devlop a
urethral obstruction - most cats aren't brought to vet for at least 24 hours
after their last meal -- this increases the probability that the urine pH
will be acidic when its tested.


>
> 2. how easy is it to determine wether it's struvite or calcium oxalate? in
> the microscope there can be seen a variety of shapes and forms of crystals
> (but not a great number of them). is there another more accurate method?


Optical crystallography, thermal analysis, infrared spectrophotometry,
electron microprobe analysis, x-ray diffraction, -- or a combination of
these methods. Microscopic examination only identifies the outside of a
urolith. Some uroliths have a mixed composition - IOW, they have a nucleus
composed of calcium oxalate and a shell composed of struvite. That's why
quantitative mineral analysis, rather than qualitive analysis is so
important.

Also, there's a big difference between struvite uroliths and struvite
urethral plugs. Uroliths are made up of mostly of magnesium ammonium
phosphate (MAP) and small amounts of matrix. Struvite plugs are usually
made up of large amounts of matrix mixed with small amounts of MAP.. Some
urethral plugs are made up of organic matrix, sloughed tissue, blood, and/or
debris, and others are form in association with an infection
(infection-induced struvite).

Plugs are more common in male cats than actual uroliths - which are more
common in females. If your cat has struvite plugs, the prescription diet
isn't going to help that much.

hth,

Phil

tunic
December 10th 04, 01:50 PM
thanks for your response

>Optical crystallography, thermal analysis, infrared >spectrophotometry,
>electron microprobe analysis, x-ray diffraction, -- or a >combination of
these methods

unfortunately, most of these methods arent available where i live (a small
town in greece). the only thing they could do to identify the case was the
cat to have formed a stone and this stone to be surgically removed and
examined..

anyway, the vet has come to the conclusion that it is sturvite uroliths
(there werent any signs of infection, the cat was in perfect health even
during the hospitalization)
and we are currently feeding with Hill's s/d diet in order to dissolve
them -but meanwhile he had a couple of blockages which we got over with
temporary catheterization
i think the last resort will be urethrostomy..

the vet assured me that there wont be any side-effects by urethrostomy
though i have read that the cat will be more prone to bladder infections
and the stone formation is going to get more intense- it just wont induce
blockage, can you shed any light to this?
is urethrostomy to be considered as the last resort or is it a common
procedure?

thanks

Phil P.
December 10th 04, 03:43 PM
"tunic" > wrote in message
lkaboutpets.com...
> thanks for your response
>
> >Optical crystallography, thermal analysis, infrared >spectrophotometry,
> >electron microprobe analysis, x-ray diffraction, -- or a >combination of
> these methods
>
> unfortunately, most of these methods arent available where i live (a small
> town in greece). the only thing they could do to identify the case was the
> cat to have formed a stone and this stone to be surgically removed and
> examined..
>
> anyway, the vet has come to the conclusion that it is sturvite uroliths
> (there werent any signs of infection, the cat was in perfect health even
> during the hospitalization)
> and we are currently feeding with Hill's s/d diet in order to dissolve
> them -but meanwhile he had a couple of blockages which we got over with
> temporary catheterization
> i think the last resort will be urethrostomy..
>
> the vet assured me that there wont be any side-effects by urethrostomy
> though i have read that the cat will be more prone to bladder infections
> and the stone formation is going to get more intense- it just wont induce
> blockage, can you shed any light to this?
> is urethrostomy to be considered as the last resort or is it a common
> procedure?


Perineal urethrostomy sure is a last resort; the procedure literally turns a
male cat into an anatomical female. First the scrotal skin and prepuce are
removed to free and expose the penis. Then the muscles that hold the penis
to the pelvic bones are cut - this allows the penis to be pulled outside of
the body a little more than it normally is. The penis is then split along
the urethra to the widest part of the urethra. Then, the opened urethra is
(very delicately) sutured to the skin, part of the penis is removed, and
all skin edges are closed. If its done right, the cat is now sort of an
anatomical female with a w i d e urethral opening so stones or crystals
can't jam and plug the cat. But the cat will not have the host defense
system of a female and will be prone to UTIs.

I watched a few procedures and I can tell you its not as bad as it sounds...
although I did get the chills.

P.U.s are usually only necessary for calcium oxalate cases because CaOx
can't be dissolved. If your vet is recommending a PU in a struvite case,
its quite possible he damaged the urethra during catheterization.

This is *definitely* a last resort procedure so I would seek a second
opinion if I were you.

Good luck.

Phil.

tunic
December 10th 04, 07:45 PM
hi,

today my cat had another blockage which was due to a stone which had moved
down in the urethra. the vet had great difficulty passing the cathetere
and could feel the resistence by the stone (it is almost certain that its
struvite stone) but eventually it went through
the urine was quite clear of crystals (and blood) so we presume that it
was a sole stone that has pretty much been dissolved by the
catheterization
but how safe is this assumption? should we proceed to PU even knowing that
it is a struvite case? would an x-ray show anything?
i'm really hopeless..

ps i am in close contact with the vet so i'm aware of all her movements

Phil P.
December 10th 04, 08:06 PM
"tunic" > wrote in message
lkaboutpets.com...
> hi,
>
> today my cat had another blockage which was due to a stone which had moved
> down in the urethra. the vet had great difficulty passing the cathetere
> and could feel the resistence by the stone (it is almost certain that its
> struvite stone) but eventually it went through
> the urine was quite clear of crystals (and blood) so we presume that it
> was a sole stone that has pretty much been dissolved by the
> catheterization
> but how safe is this assumption? should we proceed to PU even knowing that
> it is a struvite case? would an x-ray show anything?
> i'm really hopeless..
>
> ps i am in close contact with the vet so i'm aware of all her movements


Struvite is radiodense so it should detectable on x-rays - an ultrasound
would be idea. I would certainly opt for x-rays or ideally ultrasounds
before going forward with such a drastic procedure or risking another
obstruction. Remember, if an obstruction occurs over the weekend or your
vet is unavailable, your cat could die - complete obstruction produces a
pathophysiologic state equivalent to oliguric acute renal failure.

If the problem was caused by a single stone, the cost of the imaging is
negligible compared to the surgery and treatment for recurring UTIs - not to
mention sparing the cat of the trauma and stress.

Phil

tunic
December 14th 04, 09:22 PM
hi,

an x-ray showed nothing and its hard for the vet to analyze an ultrasound,
she is not an expert at that..
after the removal of the cathetere (second catheterization in 2 weeks) the
urine still contained a few crystals which showed in the microscope as
typical struvite ones (rectangular envelope-shaped). is it logical since
the cat is being fed canned hills s/d for the last 2 weeks? he is now
straining to urinate but he eventually manages to empty his bladder..
the vet said if he has another blocakge he'll go for urehtrostomy.. what
else is there to do ?

thanks..

Phil P.
December 14th 04, 09:56 PM
"tunic" > wrote in message
lkaboutpets.com...
> hi,
>
> an x-ray showed nothing and its hard for the vet to analyze an ultrasound,
> she is not an expert at that..
> after the removal of the cathetere (second catheterization in 2 weeks) the
> urine still contained a few crystals which showed in the microscope as
> typical struvite ones (rectangular envelope-shaped). is it logical since
> the cat is being fed canned hills s/d for the last 2 weeks? he is now
> straining to urinate but he eventually manages to empty his bladder..
> the vet said if he has another blocakge he'll go for urehtrostomy.. what
> else is there to do ?
>
> thanks..


Are you free feeding (ad libitum) your cat or do you feed him twice a day
(b.i.d.)? Feeding releases bicarbonate which produces an alkaline tide that
causes transient alkalinization of the urine. Free-feeding protracts
postprandial alkalinization of the urine throughout the day. Although the
alkaline tide is much "higher" after b.i.d. feeding, its shorter in
duration. Enough time elapses between meals for natural acidity to return
and disolve struvite.

At urine pH less than 6.1, struvite does not form regardless of the
magnesium concentration of the diet. So if you're finding struvite in pH 6
urine, the crystals may not be struvite.

Buy a tube of urine dipsticks and monitor his urine pH throughout the day.

I hope you find a solution quickly.

Good luck.

Phil

tunic
December 16th 04, 11:49 AM
no luck...

i'm feeding him twice a day
but he seems to have been blocked again
i took him to the vet and she pressed his bladder and only a tiny flow
came out. so there must be a stone in his urethra which cant be removed
and the only solution is PU..
if there are any final suggestions please let me know

thank you very much

Phil P.
December 16th 04, 01:35 PM
"tunic" > wrote in message
lkaboutpets.com...
> no luck...
>
> i'm feeding him twice a day
> but he seems to have been blocked again
> i took him to the vet and she pressed his bladder and only a tiny flow
> came out. so there must be a stone in his urethra which cant be removed
> and the only solution is PU..
> if there are any final suggestions please let me know
>
> thank you very much


I'm running out of alternatives to surgery.

In some cases acidifers are administered and a urinary catheter is sewn in
place for several days to keep the urine flowing while the stone dissolves.
This is a little risky because acidification of the urine is not without
potential toxicity (hemolytic anemia, met hemoglobinemia, and Heinz body
formation, and possibly renal damage). Acidification may be of no benefit
if your cat is obstructed with a plug instead of a stone. Also, a
difinitive analysis of struvite has not been made.

There are usually only 2 places where a stone/plug can lodge. One place is
where urethra narrows, sort of like a funnel, where its passes over the
pelvis into the penis. (see illustration on my site).

http://www.maxshouse.com/Anatomy/anatomy_urogenital_sys.jpg

The other place is in the tip of the penis where urethra is the narrowest.
*If* the obstruction is in the tip of the penis, and your vet has keen
surgical skills, you just might, *might* get through this crisis with a
urethrotomy instead of a urethrostomy. A urethrotomy differs from a
urethrostomy in that only a temporary opening is made in the penis and
urethra to remove a lodged stone or plug and to provide an opening for
temporary urine flow. The layers of skin, penis, and urethra are opened,
then sutured closed in reverse order. The cat gets to keep his penis. Since
the technique is very similar for both procedures, perhaps your vet can
begin with a urethrotomy and continue on to a urethrostomy if the stone is
not lodged in the tip of the penis.

However, I'm very concerned about the patency of the urethra. Repeated
blockages and catheterizations may have severely damaged the urethra leaving
no alternatives to a perineal urethrostomy.

At this stage, and due to the likelihood of urethral damage and the high
risk of obstruction-induced oliguric acute renal failure, and the discomfort
and stress of repeated blockages and catheterizations, if he were my cat, I
think I would go ahead with the urethrostomy. UTIs are trivial in
comparison to the other alternatives. But that's merely my opinion and I
could be wrong.

It looks like we're back to where we started. I wish I could be more
helpful.

Please keep me posted.

Best of luck.

Phil

tunic
December 16th 04, 03:15 PM
how are plugs identified? he hadnt any signs of infection or too much blood
in his urine
there were certainly many crystals though, could it be a combination of
the two?

while trying to pass the cathetere the last time, the vet met an obstacle
(she could sense it)
she cleaned the edge of the cathetere and analyzed the contents in the
microscope where many crystals were visible
she believes that the cathetere eventually passed *by* the stone in the
urethra so the catheterization or the acidification (by s/d food) hadnt
had any effect on the real problem. is that possible? i think the
cathetere is quite wide for that to happen

the good thing is that the cat is in good shape, he is almost used to the
procedure (he was even once catheterized without sedation) and he was
never anorexic. oh and he peed quite a bit after coming home from the vet
today..
is it possible his current difficulty to urinate to be due to urethra
inflammation and not stones?
i'm still having second thoughts about PU but am i just putting off the
inevitable?

Phil P.
December 16th 04, 05:57 PM
"tunic" > wrote in message
lkaboutpets.com...
> how are plugs identified? he hadnt any signs of infection or too much
blood
> in his urine
> there were certainly many crystals though, could it be a combination of
> the two?

Urethral plugs are a combination of a small amount of calculus (usually
struvite) and large amounts of mucus, which is probably secreted by mucosal
cells in the bladder and urethra - most likely in response to some mucosal
irritant and/or inflammation. Struvite uroliths contain larger quantities
MAP and smaller quantities of mucus and other debris.


>
> while trying to pass the cathetere the last time, the vet met an obstacle
> (she could sense it)
> she cleaned the edge of the cathetere and analyzed the contents in the
> microscope where many crystals were visible
> she believes that the cathetere eventually passed *by* the stone in the
> urethra

She may have pushed the obstruction back to a wider point in the urethra. A
technique called "retrograde urohydropropulsion" is often used flush an
obstruction back into the bladder by distending the urethra around the stone
with fluid - this is only for temporary relief. Voiding urohydropulsion is
used to eliminate urethral stones if the stones/plugs are small enough.



so the catheterization or the acidification (by s/d food) hadnt
> had any effect on the real problem. is that possible? i think the
> cathetere is quite wide for that to happen

I think you're right.


>
> the good thing is that the cat is in good shape, he is almost used to the
> procedure (he was even once catheterized without sedation) and he was
> never anorexic. oh and he peed quite a bit after coming home from the vet
> today..
> is it possible his current difficulty to urinate to be due to urethra
> inflammation and not stones?

Sure its possible. Crystals alone can inflame the urethra - and repeated
catheterizations can certaily inflame the urethra. Perhaps an
antiinflammarory med might help. Inflammation in the urethra is analogous
to rust and corrosion inside a pipe. Reducing the inflammation would
probably increase (restore) urethral diameter.

Its also possible that she broke up the stone - don't forget, he's on s/d -
so struvite would be soluble in an acidic urine.


> i'm still having second thoughts about PU but am i just putting off the
> inevitable?

Maybe not. Lets keep our paws crossed!

Phil



>
>

tunic
December 16th 04, 06:36 PM
i sent him for PU afterall..
the PU vet told me that it is almost certain that it will happen again,
even if he gets well now, so there's no point avoiding it
i am regretting it now but i hope it will turn out ok
thanks for all the information and the support..

Phil P.
December 17th 04, 12:10 PM
"tunic" > wrote in message
lkaboutpets.com...
> i sent him for PU afterall..
> the PU vet told me that it is almost certain that it will happen again,
> even if he gets well now, so there's no point avoiding it
> i am regretting it now but i hope it will turn out ok
> thanks for all the information and the support..

At this stage, you didn't have much choice, not with repeated blockages.
Urinary tract obstructions are potentially fatal and there's always the risk
of not getting him to an emergency clinic in time -- not to mention the
stress and discomfort.

The only other suggestion I can make is keep his litterboxes immaculately
clean. The PU will turn him into an anatomical female but he will not have
the host defenses of a female. Infections can easily ascend to the
bladder - meaning literally, they crawl up from outside and have a shorter
distance to travel.

You did the right thing.

Best of luck.

Phil.

tunic
December 17th 04, 08:44 PM
thanks.. the PU vet also had big difficulty in passing the cathetere in
order to make the urethrostomy so i guess it was the right thing to do..
i got him back home today, he has a small cathetere sewed on (for 5 days)
i will be using shredded newspaper for litter
he is a housecat and doesnt go out, is it possible to get infected by
sitting to a dirty place or something like that?

thanks again

tunic
December 21st 04, 08:52 AM
it is so tragic, he blocked again after being PUed and with a cathetere 3
times wider
of course this cathetere is only 2 cm long and wont reach in the bladder
so this happened before the cathetere
i'm afraid that the problem will be worse when the cathetere will be
removed and once again we will be where we started (except that now the
cat has no genital system and has been tormented as hell)
i wish we could fight the cause and not just the symptoms..

Phil P.
December 21st 04, 11:06 PM
"tunic" > wrote in message
lkaboutpets.com...
> it is so tragic, he blocked again after being PUed and with a cathetere 3
> times wider
> of course this cathetere is only 2 cm long and wont reach in the bladder
> so this happened before the cathetere
> i'm afraid that the problem will be worse when the cathetere will be
> removed and once again we will be where we started (except that now the
> cat has no genital system and has been tormented as hell)
> i wish we could fight the cause and not just the symptoms..


This should not have happened. Apparently, the PU wasn't performed
correctly. I think a big part of your cat's problem is a bungling,
incompetent vet. I strongly suggest you seek a second opinion - quick -
before you lose your cat to acute renal failure due the vet's gross
incompetence.

I'm sure you have veterinary teaching college in your country, contact them
for a referral to another vet and ask about their procedure for submitting
crystals for analysis. If he's still forming uroliths in a highly acidic
urine, there's a very good chance that the crystals aren't struvite - or
completely struvite.

I'm sorry if I sound harsh - I'm infuriated by the stress and trauma this
matchbook vet is putting your cat through.

Please do not hesitate in obtaining a referral and second opinion.

Phil

tunic
December 22nd 04, 02:38 PM
hmm the vet who performed the PU was different than the casual one and she
is much experienced in situations like this (although she found a small
stone during the operation but lost it!!! there goes our chance identify
the exact composition of the stones..)
the casual vet has contacted at least two other vets to get their opinion,
and is much caring, i wouldnt say she is not competent..
i just think that my cat is cursed, the first day he traumatized the wound
with the e-collar and he was bleeding like hell
today the small cathetere got lost inside the opening (the stitches were
cut) and fortunately the vet managed to pull it out

the urine PH was 6 (5-6 hours after the feeding) but maybe there are
stones which take time to dissolve (he's been on s/d for 3 weeks)
the vet is definite about it being struvite.. we had also sent an urine
sample to a microbiologist who found crystals with an ammonium phosphate
compsition

i dont know what else to expect..(hope not a renal failure)

tunic
December 27th 04, 06:38 PM
hi,

i followed your suggestion and took the cat to another vet.
he did a urine analysis and concluded (with complete certainty- as much as
the other vets had for the opposite conclusion) that there were calcium
oxalate crystals in the urine.
fortunately i have already stopped feeding him s/d food for a few days now
(i'm giving him waltham's urinary which is supposed to prevent both kinds
of stones) and he has managed to pee (i dont know if this was due to the
food's effect or it was simply coincidental)
the PU vet cut the stiches today and stiched again a broad cathetere for 2
days to prevent a symphysis from occurring

i am really outraged with all this, i dont know what to believe. can these
people be called scientists? i think not.. maybe they think my cat is a
guinea pig and can do experiments to him

Phil P.
December 27th 04, 08:39 PM
"tunic" > wrote in message
lkaboutpets.com...
> hi,
>
> i followed your suggestion and took the cat to another vet.
> he did a urine analysis and concluded (with complete certainty- as much as
> the other vets had for the opposite conclusion) that there were calcium
> oxalate crystals in the urine.


I knew the first vet screwed up the stone analysis, goddamit. Struvite
doesn't form in urine pH at 6.1 or lower.


> fortunately i have already stopped feeding him s/d food for a few days now
> (i'm giving him waltham's urinary which is supposed to prevent both kinds
> of stones) and he has managed to pee (i dont know if this was due to the
> food's effect or it was simply coincidental)

> the PU vet cut the stiches today and stiched again a broad cathetere for 2
> days to prevent a symphysis from occurring
>
> i am really outraged with all this,


I'm ****ed as hell -- and he's not even my cat! If he were my cat, I'd
probably need to be restrained. This was not simply a mistake. It was
gross negligence by failing to have the stone analyzed properly before
prescribing a treatment.


i dont know what to believe. can these
> people be called scientists? i think not.. maybe they think my cat is a
> guinea pig and can do experiments to him

I'd tell the bungling vet that you want to renegotiate the bill or else she
can negotiate a malpractice suit for performing an unnecessary
*irreversible* drastic surgery and causing you and your cat unnecessary
pain, suffering and stress - not to mention the cost of surgery and repeated
vet visits.

I would take legal action, not only because of you and your cat's
experience, but also for the health and welfare of other animals that this
incompetent vet might affect.

Lets hope he's on the road to complete recovery.

Phil

Johnna O'Leary via CatKB.com
January 12th 05, 04:56 AM
Hi Tunic and Phil,
I am new to this board so please forgive me if it is not proper ettiquite to join your conversation. Tunic, I am so sorry to hear about your cat's troubles. I sincerely hope you have found a solution that will bring relief to the both of you. I can empathize with your situation - my cat has been struggling with repeated blockages as well. I have never experienced anything so frustrating. Best of luck to you and your kitty.

Phil, you seem extraordinarily knowledgable about this condition. Are you a vet? Hats off to you for supporting Tunic and her kitty through their ordeal.

--
Message posted via http://www.catkb.com

Phil P.
January 12th 05, 07:50 AM
"Johnna O'Leary via CatKB.com" > wrote in message
...
> Hi Tunic and Phil,
> I am new to this board so please forgive me if it is not proper ettiquite
to join your conversation.

Discussions are open to everyone. There are no private conversations in
newsgroups. ;-)


> Tunic, I am so sorry to hear about your cat's troubles. I sincerely hope
you have found a solution that will bring relief to the both of you. I can
empathize with your situation - my cat has been struggling with repeated
blockages as well. I have never experienced anything so frustrating. Best of
luck to you and your > >kitty.


I'm concerned because I haven't seen an update in a few weeks. I hope all
is well.

>
> Phil, you seem extraordinarily knowledgable about this condition. Are you
a vet?

No. I just work with a lot of cats.


>Hats off to you for supporting Tunic and her kitty through their ordeal.


Thanks. I just hope the cat is finally doing well. I get nervous when I
don't see an update.

Phil.
--
"With the qualities of cleanliness, discretion, affection, patience,
dignity, and courage that cats have, how many of us,
I ask you, would be capable of being cats?' --Fernand Mery
Feline Healthcare & More: <http://maxshouse.com



>
> --
> Message posted via http://www.catkb.com