Thyroid surgery

"Mary" wrote in message
.com...

"Phil P." wrote

This one:

http://www.lbah.com/Feline/hyperthyroidism.htm#patho

does indeed discuss the issue of elevated liver enzymes due to
hyperthyroidism, and says that *if* they are secondary to (e.g. caused by)
the condition they will return to normal when the thryoid is treated. What
really worries me is probably what worries my doctor: what if her elevated
liver enzyme levels are NOT secondary to the thyroid disease, and the
tapazole further damages her liver? Liver damage is irreversable.

Although I understand your vet's concern - that the liver enzymes may be
elevated due to a primary reason Vs. secondary, actually the liver does
often repair itself.

As one ex., the cat Debbie I mentioned - who had liver disease (w/ sky-high
values) & was also hyperthyroid, her liver values eventually returned to
normal, w/ proper treatment.

Cathy

"Cheryl" wrote in message
...
In the fine newsgroup "rec.pets.cats.health+behav", "Mary"
artfully composed this message within
r.com on 18 Jul
2004:

Liver damage is irreversable.

No, it isn't.

Heh! I picked up on the exact same passage as you did!

Cathy

Shadow had hepatic lipidosis and his liver values were
horrible. Proper nutrician whether he wanted it or not, reversed his
liver damage. Along with Denosyl (some sort of Sam E).

--
Cheryl

"Cheryl" wrote in message
...
In the fine newsgroup "rec.pets.cats.health+behav", "Mary"
artfully composed this message within
r.com on 18 Jul
2004:

Liver damage is irreversable.

No, it isn't.

Heh! I picked up on the exact same passage as you did!

Cathy

Shadow had hepatic lipidosis and his liver values were
horrible. Proper nutrician whether he wanted it or not, reversed his
liver damage. Along with Denosyl (some sort of Sam E).

--
Cheryl

"Mary" wrote in message
.com...


My conclusion is that you are wrong about there being any advantage to
putting her on Tapazole first, except financial.


My post was in response to your statement that your vet did not know
hyperthyroidism was probably the cause of your cat's elevated liver enzymes.
You wanted articles to support my statement. *All* the links I provided
certainly proved my point.

Now you're saying I'm wrong about there being any advantage to putting your
cat on Tapazole before going ahead with I-131 tx. shakes head

It doesn't seem like you fully understand the effects of hyperthyroidism on
other organs. I'll try to enlighten you. Hyperthyroidism in cats causes
tachycardia and increased cardiac output, and hypertension as well increased
renal blood flow and GFR. An elevated GFR will mask underlying renal
disease because the kidneys are filtering more blood at a faster rate than
at a normal GFR. This is why the BUN/Cr. in hyperthyroid cats with renal
disease are usually within the normal ranges. Following treatment of
hyperthyroidism and return to euthyroidism, cardiac output and, hence, GFR
could drop, causing clinical development of overt renal failure in cats with
underlying or subclinical renal disease.

The purpose of treating a cat with Tapazole prior to I-131 tx is to return
the cat to euthyroidism (where the cat would be after I-131 tx) and
evaluate kidney function. If kidney function deteriorates while the cat is
on Tapazole, then a permanent cure (I-131) is not an option. If the cat's
kidney function remains stable while the cat is euthyroid on Tapazole, then
she would be a good candidate for I-131 tx. This screening process is
pretty much SOP for hyperthyroid cats prior to I-131 tx.


Here's a link that explains what I just wrote in case I wasn't clear enough:

http://www.marvistavet.com/html/thyr...diotherap.html



Here's a journal abstract that documents the changes in renal function in
cats following treatment of hyperthyroidism with I-131 and why its so
important to investigate kidney function before I-131 tx.







Vet Radiol Ultrasound 1997 May-Jun;38(3):231-8



Changes in renal function in cats following treatment of hyperthyroidism
using 131I.



Adams WH, Daniel GB, Legendre AM, Gompf RE, Grove CA.



Department of Small Animal Clinical Sciences, University of Tennessee,
College

of Veterinary Medicine, Knoxville 37901-1071, USA.



"Changes in renal function of twenty-two cats treated for hyperthyroidism
using

radioiodine were evaluated. Serum thyroxine (T4), serum creatinine, blood
urea

nitrogen (BUN) and urine specific gravity were measured before treatment and
6

and 30 days after treatment. Twenty-two cats had pretreatment and 21 cats
had 6

day posttreatment measurement of glomerular filtration rate (GFR) using
nuclear

medicine imaging techniques. There were significant declines in serum T4 at
6

days following treatment, but the changes in GFR, serum creatinine and BUN
were

not significant. At 30 days following treatment, there were significant

increases in BUN and serum creatinine and further significant declines in
serum

T4. Nine cats were in renal failure prior to treatment and 13 cats were in
renal

failure 30 days following treatment. Renal failure was defined as BUN
greater

than 30 mg/dl and/or serum creatinine greater than 1.8 mg/dl with concurrent

urine specific gravity less than 1.035. These 13 cats included eight of 9
cats

in renal failure prior to treatment and 5 cats not previously in renal
failure.

Follow up information beyond 30 days following treatment on 9 of these 13
cats

indicated that all remained in renal failure. Based on receiver operating
curve

analysis of pretreatment glomerular filtration rate (GFR) in predicting

posttreatment renal failure, a value of 2.25 ml/kg/min as a point of maximum

sensitivity (100%) and specificity (78%) was derived. Fifteen of 22 cats had

pretreatment GFR measurements of less than 2.25 ml/kg/min. These 15 cats

included all 9 cats in renal failure and 5 cats with normal renal

clinicopathologic values prior to treatment. At 30 days following treatment,
13

of these 15 cats were in renal failure. The 2 cats not in renal failure had

persistently increased serum T4 values. Seven of 22 cats had pretreatment
GFR

measurements greater than 2.25 ml/kg/min. None of these 7 cats was in renal

failure at 30 days following treatment, all cats having normal BUN, serum

creatinine, and urine specific gravity values. It was concluded that
significant

declines in renal function occur after treatment of hyperthyroidism and this

decline is clinically important in cats with renal disease. Pretreatment

measurement of GFR is valuable in detecting subclinical renal disease and in

predicting which cats may have clinically important declines in renal
function

following treatment."

"Mary" wrote in message
.com...


My conclusion is that you are wrong about there being any advantage to
putting her on Tapazole first, except financial.


My post was in response to your statement that your vet did not know
hyperthyroidism was probably the cause of your cat's elevated liver enzymes.
You wanted articles to support my statement. *All* the links I provided
certainly proved my point.

Now you're saying I'm wrong about there being any advantage to putting your
cat on Tapazole before going ahead with I-131 tx. shakes head

It doesn't seem like you fully understand the effects of hyperthyroidism on
other organs. I'll try to enlighten you. Hyperthyroidism in cats causes
tachycardia and increased cardiac output, and hypertension as well increased
renal blood flow and GFR. An elevated GFR will mask underlying renal
disease because the kidneys are filtering more blood at a faster rate than
at a normal GFR. This is why the BUN/Cr. in hyperthyroid cats with renal
disease are usually within the normal ranges. Following treatment of
hyperthyroidism and return to euthyroidism, cardiac output and, hence, GFR
could drop, causing clinical development of overt renal failure in cats with
underlying or subclinical renal disease.

The purpose of treating a cat with Tapazole prior to I-131 tx is to return
the cat to euthyroidism (where the cat would be after I-131 tx) and
evaluate kidney function. If kidney function deteriorates while the cat is
on Tapazole, then a permanent cure (I-131) is not an option. If the cat's
kidney function remains stable while the cat is euthyroid on Tapazole, then
she would be a good candidate for I-131 tx. This screening process is
pretty much SOP for hyperthyroid cats prior to I-131 tx.


Here's a link that explains what I just wrote in case I wasn't clear enough:

http://www.marvistavet.com/html/thyr...diotherap.html



Here's a journal abstract that documents the changes in renal function in
cats following treatment of hyperthyroidism with I-131 and why its so
important to investigate kidney function before I-131 tx.







Vet Radiol Ultrasound 1997 May-Jun;38(3):231-8



Changes in renal function in cats following treatment of hyperthyroidism
using 131I.



Adams WH, Daniel GB, Legendre AM, Gompf RE, Grove CA.



Department of Small Animal Clinical Sciences, University of Tennessee,
College

of Veterinary Medicine, Knoxville 37901-1071, USA.



"Changes in renal function of twenty-two cats treated for hyperthyroidism
using

radioiodine were evaluated. Serum thyroxine (T4), serum creatinine, blood
urea

nitrogen (BUN) and urine specific gravity were measured before treatment and
6

and 30 days after treatment. Twenty-two cats had pretreatment and 21 cats
had 6

day posttreatment measurement of glomerular filtration rate (GFR) using
nuclear

medicine imaging techniques. There were significant declines in serum T4 at
6

days following treatment, but the changes in GFR, serum creatinine and BUN
were

not significant. At 30 days following treatment, there were significant

increases in BUN and serum creatinine and further significant declines in
serum

T4. Nine cats were in renal failure prior to treatment and 13 cats were in
renal

failure 30 days following treatment. Renal failure was defined as BUN
greater

than 30 mg/dl and/or serum creatinine greater than 1.8 mg/dl with concurrent

urine specific gravity less than 1.035. These 13 cats included eight of 9
cats

in renal failure prior to treatment and 5 cats not previously in renal
failure.

Follow up information beyond 30 days following treatment on 9 of these 13
cats

indicated that all remained in renal failure. Based on receiver operating
curve

analysis of pretreatment glomerular filtration rate (GFR) in predicting

posttreatment renal failure, a value of 2.25 ml/kg/min as a point of maximum

sensitivity (100%) and specificity (78%) was derived. Fifteen of 22 cats had

pretreatment GFR measurements of less than 2.25 ml/kg/min. These 15 cats

included all 9 cats in renal failure and 5 cats with normal renal

clinicopathologic values prior to treatment. At 30 days following treatment,
13

of these 15 cats were in renal failure. The 2 cats not in renal failure had

persistently increased serum T4 values. Seven of 22 cats had pretreatment
GFR

measurements greater than 2.25 ml/kg/min. None of these 7 cats was in renal

failure at 30 days following treatment, all cats having normal BUN, serum

creatinine, and urine specific gravity values. It was concluded that
significant

declines in renal function occur after treatment of hyperthyroidism and this

decline is clinically important in cats with renal disease. Pretreatment

measurement of GFR is valuable in detecting subclinical renal disease and in

predicting which cats may have clinically important declines in renal
function

following treatment."

"Phil P." wrote


It doesn't seem like you fully understand the effects of hyperthyroidism
on other organs. I'll try to enlighten you.

Thank you.

Hyperthyroidism in cats causes tachycardia and increased cardiac output,
and hypertension as well increased renal blood flow and GFR. An elevated
GFR will mask underlying renal disease because the kidneys are filtering
more blood at a faster rate than
at a normal GFR. This is why the BUN/Cr. in hyperthyroid cats with renal
disease are usually within the normal ranges. Following treatment
ofhyperthyroidism and return to euthyroidism, cardiac output and, hence,
GFR could drop, causing clinical development of overt renal failure in cats
with underlying or subclinical renal disease.

The purpose of treating a cat with Tapazole prior to I-131 tx is to
return the cat to euthyroidism (where the cat would be after I-131 tx) and
evaluate kidney function. If kidney function deteriorates while the cat is
on Tapazole, then a permanent cure (I-131) is not an option. If the
cat's kidney function remains stable while the cat is euthyroid on
Tapazole, then she would be a good candidate for I-131 tx. This screening
process is
pretty much SOP for hyperthyroid cats prior to I-131 tx.


NOW I understand! Thanks so much for your good-natured patience and the time
and effort it took to "enlighten me." . I'm just going to read this to the
vet in the morning.

"Phil P." wrote


It doesn't seem like you fully understand the effects of hyperthyroidism
on other organs. I'll try to enlighten you.

Thank you.

Hyperthyroidism in cats causes tachycardia and increased cardiac output,
and hypertension as well increased renal blood flow and GFR. An elevated
GFR will mask underlying renal disease because the kidneys are filtering
more blood at a faster rate than
at a normal GFR. This is why the BUN/Cr. in hyperthyroid cats with renal
disease are usually within the normal ranges. Following treatment
ofhyperthyroidism and return to euthyroidism, cardiac output and, hence,
GFR could drop, causing clinical development of overt renal failure in cats
with underlying or subclinical renal disease.

The purpose of treating a cat with Tapazole prior to I-131 tx is to
return the cat to euthyroidism (where the cat would be after I-131 tx) and
evaluate kidney function. If kidney function deteriorates while the cat is
on Tapazole, then a permanent cure (I-131) is not an option. If the
cat's kidney function remains stable while the cat is euthyroid on
Tapazole, then she would be a good candidate for I-131 tx. This screening
process is
pretty much SOP for hyperthyroid cats prior to I-131 tx.


NOW I understand! Thanks so much for your good-natured patience and the time
and effort it took to "enlighten me." . I'm just going to read this to the
vet in the morning.

Mary wrote:
"Cathy Friedmann" wrote




Well, that's also a 'once it's done, that's it' deal. Personally, even if

interested in the radioiodine treatment, I'd go with the Tapazole/med route
for a few months first, & see what happens, subsequent blood work

(thyroid levels, CRF pointers, liver values), & how the whole scenario's

going, in general, before making that leap.

The vet just called and she has slightly elevated liver enzymes, so he says
Tapazole is out as is Carbimazole and other drugs of that class because they
can cause liver damage. I had a long discussion with him, and although he
feels confident about doing the surgery, he agrees with me that the risk is
significantly higher than the radioiodine treatment.

Although I realize in this

case, it's a moot point.



Actually, no, it's not. I can actually change my mind. I'm going for the
radioiodine treatment, mostly because

1. I love this cat
2. If something goes wrong as a result of my bad decision I will want to
die.

As for my fears about using a strange vet--after a bit of thought, I feel
fairly confident that I will be able to make my concerns clear enough to
those who will do the treatment that they will be extra careful.

I'll have to take her out of town since there is nobody in Raleigh who does
this. (I had assumed the NC State VEt School would do it but he said no.)
There are apparently several places within an hour's drive that can do it.
I'll call the vet Monday and he will begin setting things up. He said he is
not sure if they will want to do an ultrasound of her heart before the
surgery. Here is the terrible thing: her thyroid levels were at about 4.0
last year and are over 10.0 now. I just hope we can pull her out of this.

Thanks for your input.


RadCats in Carrboro!!! http://www.radcats.com/

I have a friend who just recently had her cat in for this treatment.

lal

Mary wrote:
"Cathy Friedmann" wrote




Well, that's also a 'once it's done, that's it' deal. Personally, even if

interested in the radioiodine treatment, I'd go with the Tapazole/med route
for a few months first, & see what happens, subsequent blood work

(thyroid levels, CRF pointers, liver values), & how the whole scenario's

going, in general, before making that leap.

The vet just called and she has slightly elevated liver enzymes, so he says
Tapazole is out as is Carbimazole and other drugs of that class because they
can cause liver damage. I had a long discussion with him, and although he
feels confident about doing the surgery, he agrees with me that the risk is
significantly higher than the radioiodine treatment.

Although I realize in this

case, it's a moot point.



Actually, no, it's not. I can actually change my mind. I'm going for the
radioiodine treatment, mostly because

1. I love this cat
2. If something goes wrong as a result of my bad decision I will want to
die.

As for my fears about using a strange vet--after a bit of thought, I feel
fairly confident that I will be able to make my concerns clear enough to
those who will do the treatment that they will be extra careful.

I'll have to take her out of town since there is nobody in Raleigh who does
this. (I had assumed the NC State VEt School would do it but he said no.)
There are apparently several places within an hour's drive that can do it.
I'll call the vet Monday and he will begin setting things up. He said he is
not sure if they will want to do an ultrasound of her heart before the
surgery. Here is the terrible thing: her thyroid levels were at about 4.0
last year and are over 10.0 now. I just hope we can pull her out of this.

Thanks for your input.


RadCats in Carrboro!!! http://www.radcats.com/

I have a friend who just recently had her cat in for this treatment.

lal

"lal" wrote


RadCats in Carrboro!!! http://www.radcats.com/

I have a friend who just recently had her cat in for this treatment.


I'm very interested in her experience there, I take it that it was positive
as far as you know? Radcats is one of my choices.