Question:
I had my Indigo treated with the radioactive iodine about 4 1/2 years ago. He is 18 1/3 now. He is still doing alright but old age has set in. The cost was well worth it and he was only away 4 nights. — Larry and Two Black Cats, Two Grey, One White & one White&Grey
– Hide quoted text — Show quoted text – Hi, Everyone – I’m just looking for some good thoughts for Trouble. We noticed that he has been losing weight, and this past week my husband said he noticed it too. It was a gradual thing, and we both apparently initially assumed it was due to his increased activity because he plays a lot with the new kittens. However, he sometimes seems stiff in the hind region in the mornings, and his muscle mass there is clearly less – not what I’d expect if this was just an activity related weight loss. Also, he’s 9 and a half, so I called the vet and took him in this morning. Yes, the weight loss is real. (1 lb since July!!! I can’t believe I didn’t notice earlier, but his winter coat is so fluffy…) The vet thinks I’m right – drew blood and said he can palpate the thyroid and one side is noticeably larger. We find out results from the blood work tomorrow, providing everything is routine. Assuming he is Hyper-T, if he’s OK after initial treatment with tapazole, I think we’ll go for radiation if possible. Anyone with experience with this? How did your cat do? I figure Trouble has a lot of years left (I hope) so I’d like to give him the best option. Surgery seems a little risky, but I would opt for that if I can’t find a good rad place. I suspect my vet will have a lot of info for me. Thanks for listening – yes, I’m nervous on Trouble’s behalf. But at least this can be treatable. Laura Before you buy.
Response:
– Hide quoted text — Show quoted text – Laura, If Trouble is, in fact, hyperthyroid, monitor kidney function *very* closely while he’s on Tapazole. If there’s *any* deterioration in kidney function while he’s on antithyroid med, *do not* go ahead with any permanent thyroid treatment. Over the past few years, many small animal vets have noticed what appears to be a relatively high incidence of overt renal failure following treatment of hyperthyroidism. As the number of cats treated for hyperthyroidism increases, so has the incidence of renal failure following treatment. Hyperthyroidism or treatment of hyperthyroidism doesn’t cause renal failure, but treatment may irreversibly unmask underlying renal disease. Hyperthyroidism increases cardiac output and renal blood flow; thyrotoxicosis, therefore, could conceivably elevate glomerular filtration rate (GFR) causing renal function to appear normal and masking underlying renal disease. Following treatment of feline hyperthyroidism and return to euthyroidism, cardiac output and, hence, GFR could drop, causing clinical development of overt renal failure in cats with underlying disease. I would *thoroughly* investigate kidney function before thyroid treatment. BUN/creatinine measurements are crude and insensitive tests for renal function; ~75% of kidney function must be lost before elevations in either analyte are noticed. Despite the fact Trouble’s BUN/Creatinine may be normal, he may have underlying renal disease which may be irreversibly unmasked by I-131 Tx. Measurement of glomerular filtration rate is a much more accurate test of renal function than either serum BUN, creatinine or both – *especially* if Trouble has lean muscle loss. Because creatinine is mostly formed in muscle, a loss of muscle mass will result in elevated serum creatinine. I think you’ll find the below study of particular interest: 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 If you need any more information, please don’t hesitate to let me know. http://maxshouse.com/Endocrine_System_&_Disorders.htm#Hyperthyroidism As an aside, speak to your vet about potassium supplementation – may reduce his stiffness. Good luck. Phil.
Phil, Thanks so much for the info. I read a lot of additional information yesterday (that’s how I deal with nervousness – look for info and digest it)including the info at your always informative site. I will be sure to look at the paper you recommended too. I also am concerned about the lean muscle loss and the possibility of a kidney problem that’s masked by his thryoid condition (if that’s what it is). My vet is a terrific guy, and I will definitely bring up the glomerular filtration rate monitoring idea as well as the potassium. He has good instincts (I think of him as the Dr. Doolittle of Georgetown because I’m convinced he talks to the animals)and he’s always up to date. To make things better, we have the ACVIM diplomates at the VRA up in Gaithersburg, and I imagine they can do just about anything there. They are listed on the CRF page for kidney specialists, and they have a number of really sharp people there. So, I know we can find the help for whatever is needed. But yes, we will be very careful before we do anything irreversible. You mentioned in another post that some vets are using another drug (not Tapazole) to treat Hyper-T cats and that it is better tolerated with fewer side-effects. It wasn’t a beta-bocker – it was another drug specifically to block thyroid hormone effects, I believe. If you remember what it is, can you let me know? Thanks so much – I will post an update when I know what’s going on. Laura Before you buy.
Response:
– Hide quoted text — Show quoted text – Laura, If Trouble is, in fact, hyperthyroid, monitor kidney function *very* closely while he’s on Tapazole. If there’s *any* deterioration in kidney function while he’s on antithyroid med, *do not* go ahead with any permanent thyroid treatment. Over the past few years, many small animal vets have noticed what appears to be a relatively high incidence of overt renal failure following treatment of hyperthyroidism. As the number of cats treated for hyperthyroidism increases, so has the incidence of renal failure following treatment. Hyperthyroidism or treatment of hyperthyroidism doesn’t cause renal failure, but treatment may irreversibly unmask underlying renal disease. Hyperthyroidism increases cardiac output and renal blood flow; thyrotoxicosis, therefore, could conceivably elevate glomerular filtration rate (GFR) causing renal function to appear normal and masking underlying renal disease. Following treatment of feline hyperthyroidism and return to euthyroidism, cardiac output and, hence, GFR could drop, causing clinical development of overt renal failure in cats with underlying disease. I would *thoroughly* investigate kidney function before thyroid treatment. BUN/creatinine measurements are crude and insensitive tests for renal function; ~75% of kidney function must be lost before elevations in either analyte are noticed. Despite the fact Trouble’s BUN/Creatinine may be normal, he may have underlying renal disease which may be irreversibly unmasked by I-131 Tx. Measurement of glomerular filtration rate is a much more accurate test of renal function than either serum BUN, creatinine or both – *especially* if Trouble has lean muscle loss. Because creatinine is mostly formed in muscle, a loss of muscle mass will result in elevated serum creatinine. I think you’ll find the below study of particular interest: 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 If you need any more information, please don’t hesitate to let me know. http://maxshouse.com/Endocrine_System_&_Disorders.htm#Hyperthyroidism As an aside, speak to your vet about potassium supplementation – may reduce his stiffness. Good luck. Phil. Phil, Thanks so much for the info. I read a lot of additional information yesterday (that’s how I deal with nervousness – look for info and digest it)including the info at your always informative site.
I’m happy you found the information on my site helpful. Some not-so-sharp dolts criticized the information as being "too technical"…. I will be sure to look at the paper you recommended too. I also am concerned about the lean muscle loss and the possibility of a kidney problem that’s masked by his thryoid condition (if that’s what it is).
Was his T4 levels checked? If so, what was the serum T4 concentration? My vet is a terrific guy, and I will definitely bring up the glomerular filtration rate monitoring idea as well as the potassium. He has good instincts (I think of him as the Dr. Doolittle of Georgetown because I’m convinced he talks to the animals)and he’s always up to date.
A good, current vet is the most crutial factor. I’m *very* happy you have one! I think mine was a cat in a past life! He’s also an ACVIM Diplomate and former veterinary professor. Every trip to the vet is like going to "class"! He even gives me "homework"!
To make things better, we have the ACVIM diplomates at the VRA up in Gaithersburg, and I imagine they can do just about anything there.
There’s a renal funtion test that’s even more accurate; allows the assessment of each kidney indivudually, but I don’t think you need to go that far. GRF or Renal Plasma Flow (RPF) is certainly good enough. Creatinine clearance is a reasonably good indicator of glomerular filtration rate (GFR) in the cat because creatinine is excreted exclusively by glomerular filtration. Sodium sulfanilate also is excreted by glomerular filtration. These tests are a "tad" more expensive than BUN/creatinine, but well worth it. They are listed on the CRF page for kidney specialists, and they have a number of really sharp people there.
I heard the specialty of Internal Medicine will be broken down into indivudual specialties including endocrinology. They already have cardiology, oncology, neurology. ’Gotta meet some pretty tough criteria to be certified as an ACVIM Diplomate, more than than ABVP. So, I know we can find the help for whatever is needed. But yes, we will be very careful before we do anything irreversible.
As I mentioned, if kidney function begins to deteriorate while on methimazole, you may not need to test GFR. If kidney function remains stable while on medication, he should be alright – but I’d still go for test. You mentioned in another post that some vets are using another drug (not Tapazole) to treat Hyper-T cats and that it is better tolerated with fewer side-effects. It wasn’t a beta-bocker – it was another drug specifically to block thyroid hormone effects, I believe. If you remember what it is, can you let me know?
Ipodate. Its used in cats who don’t tolerate methimazole well. However, cats with severe hyperthyroidism are less likely to respond to ipodate than are cats with mild or moderate disease. You’ll need to get it from a compounding pharmacist. Don’t use Propylthiouracil, the side effects are much more severe than with methimazole. Here’s a study: J Am Vet Med Assoc 1997 Jul 1;211(1):63-7 Ipodate treatment of hyperthyroidism in cats. Murray LA, Peterson ME (The "Peterson ME" is Mark Peterson of Cornell and now head of the endocrinology dept at Animal Medical Center in NYC) Thanks so much – I will post an update when I know what’s going on. Laura
Please do. Good luck. Phil. — "Cat people are different, to the extent that they generally are not conformists. How could the be, with a cat running their lives?" –Louis Camuti Feline Healthcare: http://maxshouse.com – Hide quoted text — Show quoted text – Before you buy.
Response:
– Hide quoted text — Show quoted text – Hi, Everyone – I’m just looking for some good thoughts for Trouble. We noticed that he has been losing weight, and this past week my husband said he noticed it too. It was a gradual thing, and we both apparently initially assumed it was due to his increased activity because he plays a lot with the new kittens. However, he sometimes seems stiff in the hind region in the mornings, and his muscle mass there is clearly less – not what I’d expect if this was just an activity related weight loss. Also, he’s 9 and a half, so I called the vet and took him in this morning. Yes, the weight loss is real. (1 lb since July!!! I can’t believe I didn’t notice earlier, but his winter coat is so fluffy…) The vet thinks I’m right – drew blood and said he can palpate the thyroid and one side is noticeably larger. We find out results from the blood work tomorrow, providing everything is routine. Assuming he is Hyper-T, if he’s OK after initial treatment with tapazole, I think we’ll go for radiation if possible. Anyone with experience with this? How did your cat do? I figure Trouble has a lot of years left (I hope) so I’d like to give him the best option. Surgery seems a little risky, but I would opt for that if I can’t find a good rad place. I suspect my vet will have a lot of info for me. Thanks for listening – yes, I’m nervous on Trouble’s behalf. But at least this can be treatable. Laura
Laura, If Trouble is, in fact, hyperthyroid, monitor kidney function *very* closely while he’s on Tapazole. If there’s *any* deterioration in kidney function while he’s on antithyroid med, *do not* go ahead with any permanent thyroid treatment. Over the past few years, many small animal vets have noticed what appears to be a relatively high incidence of overt renal failure following treatment of hyperthyroidism. As the number of cats treated for hyperthyroidism increases, so has the incidence of renal failure following treatment. Hyperthyroidism or treatment of hyperthyroidism doesn’t cause renal failure, but treatment may irreversibly unmask underlying renal disease. Hyperthyroidism increases cardiac output and renal blood flow; thyrotoxicosis, therefore, could conceivably elevate glomerular filtration rate (GFR) causing renal function to appear normal and masking underlying renal disease. Following treatment of feline hyperthyroidism and return to euthyroidism, cardiac output and, hence, GFR could drop, causing clinical development of overt renal failure in cats with underlying disease. I would *thoroughly* investigate kidney function before thyroid treatment. BUN/creatinine measurements are crude and insensitive tests for renal function; ~75% of kidney function must be lost before elevations in either analyte are noticed. Despite the fact Trouble’s BUN/Creatinine may be normal, he may have underlying renal disease which may be irreversibly unmasked by I-131 Tx. Measurement of glomerular filtration rate is a much more accurate test of renal function than either serum BUN, creatinine or both – *especially* if Trouble has lean muscle loss. Because creatinine is mostly formed in muscle, a loss of muscle mass will result in elevated serum creatinine. I think you’ll find the below study of particular interest: 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 If you need any more information, please don’t hesitate to let me know. http://maxshouse.com/Endocrine_System_&_Disorders.htm#Hyperthyroidism As an aside, speak to your vet about potassium supplementation – may reduce his stiffness. Good luck. 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
Response:
Hi, Everyone – I’m just looking for some good thoughts for Trouble. We noticed that he has been losing weight, and this past week my husband said he noticed it too. It was a gradual thing, and we both apparently initially assumed it was due to his increased activity because he plays a lot with the new kittens. However, he sometimes seems stiff in the hind region in the mornings, and his muscle mass there is clearly less – not what I’d expect if this was just an activity related weight loss. Also, he’s 9 and a half, so I called the vet and took him in this morning. Yes, the weight loss is real. (1 lb since July!!! I can’t believe I didn’t notice earlier, but his winter coat is so fluffy…) The vet thinks I’m right – drew blood and said he can palpate the thyroid and one side is noticeably larger. We find out results from the blood work tomorrow, providing everything is routine. Assuming he is Hyper-T, if he’s OK after initial treatment with tapazole, I think we’ll go for radiation if possible. Anyone with experience with this? How did your cat do? I figure Trouble has a lot of years left (I hope) so I’d like to give him the best option. Surgery seems a little risky, but I would opt for that if I can’t find a good rad place. I suspect my vet will have a lot of info for me. Thanks for listening – yes, I’m nervous on Trouble’s behalf. But at least this can be treatable. Laura Before you buy.
Response:
I had my Indigo treated with the radioactive iodine about 4 1/2 years ago. He is 18 1/3 now. He is still doing alright but old age has set in. The cost was well worth it and he was only away 4 nights. — Larry and Two Black Cats, Two Grey, One White & one White&Grey
– Hide quoted text — Show quoted text – Hi, Everyone – I’m just looking for some good thoughts for Trouble. We noticed that he has been losing weight, and this past week my husband said he noticed it too. It was a gradual thing, and we both apparently initially assumed it was due to his increased activity because he plays a lot with the new kittens. However, he sometimes seems stiff in the hind region in the mornings, and his muscle mass there is clearly less – not what I’d expect if this was just an activity related weight loss. Also, he’s 9 and a half, so I called the vet and took him in this morning. Yes, the weight loss is real. (1 lb since July!!! I can’t believe I didn’t notice earlier, but his winter coat is so fluffy…) The vet thinks I’m right – drew blood and said he can palpate the thyroid and one side is noticeably larger. We find out results from the blood work tomorrow, providing everything is routine. Assuming he is Hyper-T, if he’s OK after initial treatment with tapazole, I think we’ll go for radiation if possible. Anyone with experience with this? How did your cat do? I figure Trouble has a lot of years left (I hope) so I’d like to give him the best option. Surgery seems a little risky, but I would opt for that if I can’t find a good rad place. I suspect my vet will have a lot of info for me. Thanks for listening – yes, I’m nervous on Trouble’s behalf. But at least this can be treatable. Laura Before you buy.
Response:
– Hide quoted text — Show quoted text – Laura, If Trouble is, in fact, hyperthyroid, monitor kidney function *very* closely while he’s on Tapazole. If there’s *any* deterioration in kidney function while he’s on antithyroid med, *do not* go ahead with any permanent thyroid treatment. Over the past few years, many small animal vets have noticed what appears to be a relatively high incidence of overt renal failure following treatment of hyperthyroidism. As the number of cats treated for hyperthyroidism increases, so has the incidence of renal failure following treatment. Hyperthyroidism or treatment of hyperthyroidism doesn’t cause renal failure, but treatment may irreversibly unmask underlying renal disease. Hyperthyroidism increases cardiac output and renal blood flow; thyrotoxicosis, therefore, could conceivably elevate glomerular filtration rate (GFR) causing renal function to appear normal and masking underlying renal disease. Following treatment of feline hyperthyroidism and return to euthyroidism, cardiac output and, hence, GFR could drop, causing clinical development of overt renal failure in cats with underlying disease. I would *thoroughly* investigate kidney function before thyroid treatment. BUN/creatinine measurements are crude and insensitive tests for renal function; ~75% of kidney function must be lost before elevations in either analyte are noticed. Despite the fact Trouble’s BUN/Creatinine may be normal, he may have underlying renal disease which may be irreversibly unmasked by I-131 Tx. Measurement of glomerular filtration rate is a much more accurate test of renal function than either serum BUN, creatinine or both – *especially* if Trouble has lean muscle loss. Because creatinine is mostly formed in muscle, a loss of muscle mass will result in elevated serum creatinine. I think you’ll find the below study of particular interest: 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 If you need any more information, please don’t hesitate to let me know. http://maxshouse.com/Endocrine_System_&_Disorders.htm#Hyperthyroidism As an aside, speak to your vet about potassium supplementation – may reduce his stiffness. Good luck. Phil.
Phil, Thanks so much for the info. I read a lot of additional information yesterday (that’s how I deal with nervousness – look for info and digest it)including the info at your always informative site. I will be sure to look at the paper you recommended too. I also am concerned about the lean muscle loss and the possibility of a kidney problem that’s masked by his thryoid condition (if that’s what it is). My vet is a terrific guy, and I will definitely bring up the glomerular filtration rate monitoring idea as well as the potassium. He has good instincts (I think of him as the Dr. Doolittle of Georgetown because I’m convinced he talks to the animals)and he’s always up to date. To make things better, we have the ACVIM diplomates at the VRA up in Gaithersburg, and I imagine they can do just about anything there. They are listed on the CRF page for kidney specialists, and they have a number of really sharp people there. So, I know we can find the help for whatever is needed. But yes, we will be very careful before we do anything irreversible. You mentioned in another post that some vets are using another drug (not Tapazole) to treat Hyper-T cats and that it is better tolerated with fewer side-effects. It wasn’t a beta-bocker – it was another drug specifically to block thyroid hormone effects, I believe. If you remember what it is, can you let me know? Thanks so much – I will post an update when I know what’s going on. Laura Before you buy.
Response:
– Hide quoted text — Show quoted text – Laura, If Trouble is, in fact, hyperthyroid, monitor kidney function *very* closely while he’s on Tapazole. If there’s *any* deterioration in kidney function while he’s on antithyroid med, *do not* go ahead with any permanent thyroid treatment. Over the past few years, many small animal vets have noticed what appears to be a relatively high incidence of overt renal failure following treatment of hyperthyroidism. As the number of cats treated for hyperthyroidism increases, so has the incidence of renal failure following treatment. Hyperthyroidism or treatment of hyperthyroidism doesn’t cause renal failure, but treatment may irreversibly unmask underlying renal disease. Hyperthyroidism increases cardiac output and renal blood flow; thyrotoxicosis, therefore, could conceivably elevate glomerular filtration rate (GFR) causing renal function to appear normal and masking underlying renal disease. Following treatment of feline hyperthyroidism and return to euthyroidism, cardiac output and, hence, GFR could drop, causing clinical development of overt renal failure in cats with underlying disease. I would *thoroughly* investigate kidney function before thyroid treatment. BUN/creatinine measurements are crude and insensitive tests for renal function; ~75% of kidney function must be lost before elevations in either analyte are noticed. Despite the fact Trouble’s BUN/Creatinine may be normal, he may have underlying renal disease which may be irreversibly unmasked by I-131 Tx. Measurement of glomerular filtration rate is a much more accurate test of renal function than either serum BUN, creatinine or both – *especially* if Trouble has lean muscle loss. Because creatinine is mostly formed in muscle, a loss of muscle mass will result in elevated serum creatinine. I think you’ll find the below study of particular interest: 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 If you need any more information, please don’t hesitate to let me know. http://maxshouse.com/Endocrine_System_&_Disorders.htm#Hyperthyroidism As an aside, speak to your vet about potassium supplementation – may reduce his stiffness. Good luck. Phil. Phil, Thanks so much for the info. I read a lot of additional information yesterday (that’s how I deal with nervousness – look for info and digest it)including the info at your always informative site.
I’m happy you found the information on my site helpful. Some not-so-sharp dolts criticized the information as being "too technical"…. I will be sure to look at the paper you recommended too. I also am concerned about the lean muscle loss and the possibility of a kidney problem that’s masked by his thryoid condition (if that’s what it is).
Was his T4 levels checked? If so, what was the serum T4 concentration? My vet is a terrific guy, and I will definitely bring up the glomerular filtration rate monitoring idea as well as the potassium. He has good instincts (I think of him as the Dr. Doolittle of Georgetown because I’m convinced he talks to the animals)and he’s always up to date.
A good, current vet is the most crutial factor. I’m *very* happy you have one! I think mine was a cat in a past life! He’s also an ACVIM Diplomate and former veterinary professor. Every trip to the vet is like going to "class"! He even gives me "homework"!
To make things better, we have the ACVIM diplomates at the VRA up in Gaithersburg, and I imagine they can do just about anything there.
There’s a renal funtion test that’s even more accurate; allows the assessment of each kidney indivudually, but I don’t think you need to go that far. GRF or Renal Plasma Flow (RPF) is certainly good enough. Creatinine clearance is a reasonably good indicator of glomerular filtration rate (GFR) in the cat because creatinine is excreted exclusively by glomerular filtration. Sodium sulfanilate also is excreted by glomerular filtration. These tests are a "tad" more expensive than BUN/creatinine, but well worth it. They are listed on the CRF page for kidney specialists, and they have a number of really sharp people there.
I heard the specialty of Internal Medicine will be broken down into indivudual specialties including endocrinology. They already have cardiology, oncology, neurology. ’Gotta meet some pretty tough criteria to be certified as an ACVIM Diplomate, more than than ABVP. So, I know we can find the help for whatever is needed. But yes, we will be very careful before we do anything irreversible.
As I mentioned, if kidney function begins to deteriorate while on methimazole, you may not need to test GFR. If kidney function remains stable while on medication, he should be alright – but I’d still go for test. You mentioned in another post that some vets are using another drug (not Tapazole) to treat Hyper-T cats and that it is better tolerated with fewer side-effects. It wasn’t a beta-bocker – it was another drug specifically to block thyroid hormone effects, I believe. If you remember what it is, can you let me know?
Ipodate. Its used in cats who don’t tolerate methimazole well. However, cats with severe hyperthyroidism are less likely to respond to ipodate than are cats with mild or moderate disease. You’ll need to get it from a compounding pharmacist. Don’t use Propylthiouracil, the side effects are much more severe than with methimazole. Here’s a study: J Am Vet Med Assoc 1997 Jul 1;211(1):63-7 Ipodate treatment of hyperthyroidism in cats. Murray LA, Peterson ME (The "Peterson ME" is Mark Peterson of Cornell and now head of the endocrinology dept at Animal Medical Center in NYC) Thanks so much – I will post an update when I know what’s going on. Laura
Please do. Good luck. Phil. — "Cat people are different, to the extent that they generally are not conformists. How could the be, with a cat running their lives?" –Louis Camuti Feline Healthcare: http://maxshouse.com – Hide quoted text — Show quoted text – Before you buy.
Response:
– Hide quoted text — Show quoted text – Hi, Everyone – I’m just looking for some good thoughts for Trouble. We noticed that he has been losing weight, and this past week my husband said he noticed it too. It was a gradual thing, and we both apparently initially assumed it was due to his increased activity because he plays a lot with the new kittens. However, he sometimes seems stiff in the hind region in the mornings, and his muscle mass there is clearly less – not what I’d expect if this was just an activity related weight loss. Also, he’s 9 and a half, so I called the vet and took him in this morning. Yes, the weight loss is real. (1 lb since July!!! I can’t believe I didn’t notice earlier, but his winter coat is so fluffy…) The vet thinks I’m right – drew blood and said he can palpate the thyroid and one side is noticeably larger. We find out results from the blood work tomorrow, providing everything is routine. Assuming he is Hyper-T, if he’s OK after initial treatment with tapazole, I think we’ll go for radiation if possible. Anyone with experience with this? How did your cat do? I figure Trouble has a lot of years left (I hope) so I’d like to give him the best option. Surgery seems a little risky, but I would opt for that if I can’t find a good rad place. I suspect my vet will have a lot of info for me. Thanks for listening – yes, I’m nervous on Trouble’s behalf. But at least this can be treatable. Laura
Laura, If Trouble is, in fact, hyperthyroid, monitor kidney function *very* closely while he’s on Tapazole. If there’s *any* deterioration in kidney function while he’s on antithyroid med, *do not* go ahead with any permanent thyroid treatment. Over the past few years, many small animal vets have noticed what appears to be a relatively high incidence of overt renal failure following treatment of hyperthyroidism. As the number of cats treated for hyperthyroidism increases, so has the incidence of renal failure following treatment. Hyperthyroidism or treatment of hyperthyroidism doesn’t cause renal failure, but treatment may irreversibly unmask underlying renal disease. Hyperthyroidism increases cardiac output and renal blood flow; thyrotoxicosis, therefore, could conceivably elevate glomerular filtration rate (GFR) causing renal function to appear normal and masking underlying renal disease. Following treatment of feline hyperthyroidism and return to euthyroidism, cardiac output and, hence, GFR could drop, causing clinical development of overt renal failure in cats with underlying disease. I would *thoroughly* investigate kidney function before thyroid treatment. BUN/creatinine measurements are crude and insensitive tests for renal function; ~75% of kidney function must be lost before elevations in either analyte are noticed. Despite the fact Trouble’s BUN/Creatinine may be normal, he may have underlying renal disease which may be irreversibly unmasked by I-131 Tx. Measurement of glomerular filtration rate is a much more accurate test of renal function than either serum BUN, creatinine or both – *especially* if Trouble has lean muscle loss. Because creatinine is mostly formed in muscle, a loss of muscle mass will result in elevated serum creatinine. I think you’ll find the below study of particular interest: 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 If you need any more information, please don’t hesitate to let me know. http://maxshouse.com/Endocrine_System_&_Disorders.htm#Hyperthyroidism As an aside, speak to your vet about potassium supplementation – may reduce his stiffness. Good luck. 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
Response:
Hi, Everyone – I’m just looking for some good thoughts for Trouble. We noticed that he has been losing weight, and this past week my husband said he noticed it too. It was a gradual thing, and we both apparently initially assumed it was due to his increased activity because he plays a lot with the new kittens. However, he sometimes seems stiff in the hind region in the mornings, and his muscle mass there is clearly less – not what I’d expect if this was just an activity related weight loss. Also, he’s 9 and a half, so I called the vet and took him in this morning. Yes, the weight loss is real. (1 lb since July!!! I can’t believe I didn’t notice earlier, but his winter coat is so fluffy…) The vet thinks I’m right – drew blood and said he can palpate the thyroid and one side is noticeably larger. We find out results from the blood work tomorrow, providing everything is routine. Assuming he is Hyper-T, if he’s OK after initial treatment with tapazole, I think we’ll go for radiation if possible. Anyone with experience with this? How did your cat do? I figure Trouble has a lot of years left (I hope) so I’d like to give him the best option. Surgery seems a little risky, but I would opt for that if I can’t find a good rad place. I suspect my vet will have a lot of info for me. Thanks for listening – yes, I’m nervous on Trouble’s behalf. But at least this can be treatable. Laura Before you buy.
Response:
I had my Indigo treated with the radioactive iodine about 4 1/2 years ago. He is 18 1/3 now. He is still doing alright but old age has set in. The cost was well worth it and he was only away 4 nights. — Larry and Two Black Cats, Two Grey, One White & one White&Grey
– Hide quoted text — Show quoted text – Hi, Everyone – I’m just looking for some good thoughts for Trouble. We noticed that he has been losing weight, and this past week my husband said he noticed it too. It was a gradual thing, and we both apparently initially assumed it was due to his increased activity because he plays a lot with the new kittens. However, he sometimes seems stiff in the hind region in the mornings, and his muscle mass there is clearly less – not what I’d expect if this was just an activity related weight loss. Also, he’s 9 and a half, so I called the vet and took him in this morning. Yes, the weight loss is real. (1 lb since July!!! I can’t believe I didn’t notice earlier, but his winter coat is so fluffy…) The vet thinks I’m right – drew blood and said he can palpate the thyroid and one side is noticeably larger. We find out results from the blood work tomorrow, providing everything is routine. Assuming he is Hyper-T, if he’s OK after initial treatment with tapazole, I think we’ll go for radiation if possible. Anyone with experience with this? How did your cat do? I figure Trouble has a lot of years left (I hope) so I’d like to give him the best option. Surgery seems a little risky, but I would opt for that if I can’t find a good rad place. I suspect my vet will have a lot of info for me. Thanks for listening – yes, I’m nervous on Trouble’s behalf. But at least this can be treatable. Laura Before you buy.
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– Hide quoted text — Show quoted text – Laura, If Trouble is, in fact, hyperthyroid, monitor kidney function *very* closely while he’s on Tapazole. If there’s *any* deterioration in kidney function while he’s on antithyroid med, *do not* go ahead with any permanent thyroid treatment. Over the past few years, many small animal vets have noticed what appears to be a relatively high incidence of overt renal failure following treatment of hyperthyroidism. As the number of cats treated for hyperthyroidism increases, so has the incidence of renal failure following treatment. Hyperthyroidism or treatment of hyperthyroidism doesn’t cause renal failure, but treatment may irreversibly unmask underlying renal disease. Hyperthyroidism increases cardiac output and renal blood flow; thyrotoxicosis, therefore, could conceivably elevate glomerular filtration rate (GFR) causing renal function to appear normal and masking underlying renal disease. Following treatment of feline hyperthyroidism and return to euthyroidism, cardiac output and, hence, GFR could drop, causing clinical development of overt renal failure in cats with underlying disease. I would *thoroughly* investigate kidney function before thyroid treatment. BUN/creatinine measurements are crude and insensitive tests for renal function; ~75% of kidney function must be lost before elevations in either analyte are noticed. Despite the fact Trouble’s BUN/Creatinine may be normal, he may have underlying renal disease which may be irreversibly unmasked by I-131 Tx. Measurement of glomerular filtration rate is a much more accurate test of renal function than either serum BUN, creatinine or both – *especially* if Trouble has lean muscle loss. Because creatinine is mostly formed in muscle, a loss of muscle mass will result in elevated serum creatinine. I think you’ll find the below study of particular interest: 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 If you need any more information, please don’t hesitate to let me know. http://maxshouse.com/Endocrine_System_&_Disorders.htm#Hyperthyroidism As an aside, speak to your vet about potassium supplementation – may reduce his stiffness. Good luck. Phil.
Phil, Thanks so much for the info. I read a lot of additional information yesterday (that’s how I deal with nervousness – look for info and digest it)including the info at your always informative site. I will be sure to look at the paper you recommended too. I also am concerned about the lean muscle loss and the possibility of a kidney problem that’s masked by his thryoid condition (if that’s what it is). My vet is a terrific guy, and I will definitely bring up the glomerular filtration rate monitoring idea as well as the potassium. He has good instincts (I think of him as the Dr. Doolittle of Georgetown because I’m convinced he talks to the animals)and he’s always up to date. To make things better, we have the ACVIM diplomates at the VRA up in Gaithersburg, and I imagine they can do just about anything there. They are listed on the CRF page for kidney specialists, and they have a number of really sharp people there. So, I know we can find the help for whatever is needed. But yes, we will be very careful before we do anything irreversible. You mentioned in another post that some vets are using another drug (not Tapazole) to treat Hyper-T cats and that it is better tolerated with fewer side-effects. It wasn’t a beta-bocker – it was another drug specifically to block thyroid hormone effects, I believe. If you remember what it is, can you let me know? Thanks so much – I will post an update when I know what’s going on. Laura Before you buy.
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– Hide quoted text — Show quoted text – Laura, If Trouble is, in fact, hyperthyroid, monitor kidney function *very* closely while he’s on Tapazole. If there’s *any* deterioration in kidney function while he’s on antithyroid med, *do not* go ahead with any permanent thyroid treatment. Over the past few years, many small animal vets have noticed what appears to be a relatively high incidence of overt renal failure following treatment of hyperthyroidism. As the number of cats treated for hyperthyroidism increases, so has the incidence of renal failure following treatment. Hyperthyroidism or treatment of hyperthyroidism doesn’t cause renal failure, but treatment may irreversibly unmask underlying renal disease. Hyperthyroidism increases cardiac output and renal blood flow; thyrotoxicosis, therefore, could conceivably elevate glomerular filtration rate (GFR) causing renal function to appear normal and masking underlying renal disease. Following treatment of feline hyperthyroidism and return to euthyroidism, cardiac output and, hence, GFR could drop, causing clinical development of overt renal failure in cats with underlying disease. I would *thoroughly* investigate kidney function before thyroid treatment. BUN/creatinine measurements are crude and insensitive tests for renal function; ~75% of kidney function must be lost before elevations in either analyte are noticed. Despite the fact Trouble’s BUN/Creatinine may be normal, he may have underlying renal disease which may be irreversibly unmasked by I-131 Tx. Measurement of glomerular filtration rate is a much more accurate test of renal function than either serum BUN, creatinine or both – *especially* if Trouble has lean muscle loss. Because creatinine is mostly formed in muscle, a loss of muscle mass will result in elevated serum creatinine. I think you’ll find the below study of particular interest: 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 If you need any more information, please don’t hesitate to let me know. http://maxshouse.com/Endocrine_System_&_Disorders.htm#Hyperthyroidism As an aside, speak to your vet about potassium supplementation – may reduce his stiffness. Good luck. Phil. Phil, Thanks so much for the info. I read a lot of additional information yesterday (that’s how I deal with nervousness – look for info and digest it)including the info at your always informative site.
I’m happy you found the information on my site helpful. Some not-so-sharp dolts criticized the information as being "too technical"…. I will be sure to look at the paper you recommended too. I also am concerned about the lean muscle loss and the possibility of a kidney problem that’s masked by his thryoid condition (if that’s what it is).
Was his T4 levels checked? If so, what was the serum T4 concentration? My vet is a terrific guy, and I will definitely bring up the glomerular filtration rate monitoring idea as well as the potassium. He has good instincts (I think of him as the Dr. Doolittle of Georgetown because I’m convinced he talks to the animals)and he’s always up to date.
A good, current vet is the most crutial factor. I’m *very* happy you have one! I think mine was a cat in a past life! He’s also an ACVIM Diplomate and former veterinary professor. Every trip to the vet is like going to "class"! He even gives me "homework"!
To make things better, we have the ACVIM diplomates at the VRA up in Gaithersburg, and I imagine they can do just about anything there.
There’s a renal funtion test that’s even more accurate; allows the assessment of each kidney indivudually, but I don’t think you need to go that far. GRF or Renal Plasma Flow (RPF) is certainly good enough. Creatinine clearance is a reasonably good indicator of glomerular filtration rate (GFR) in the cat because creatinine is excreted exclusively by glomerular filtration. Sodium sulfanilate also is excreted by glomerular filtration. These tests are a "tad" more expensive than BUN/creatinine, but well worth it. They are listed on the CRF page for kidney specialists, and they have a number of really sharp people there.
I heard the specialty of Internal Medicine will be broken down into indivudual specialties including endocrinology. They already have cardiology, oncology, neurology. ’Gotta meet some pretty tough criteria to be certified as an ACVIM Diplomate, more than than ABVP. So, I know we can find the help for whatever is needed. But yes, we will be very careful before we do anything irreversible.
As I mentioned, if kidney function begins to deteriorate while on methimazole, you may not need to test GFR. If kidney function remains stable while on medication, he should be alright – but I’d still go for test. You mentioned in another post that some vets are using another drug (not Tapazole) to treat Hyper-T cats and that it is better tolerated with fewer side-effects. It wasn’t a beta-bocker – it was another drug specifically to block thyroid hormone effects, I believe. If you remember what it is, can you let me know?
Ipodate. Its used in cats who don’t tolerate methimazole well. However, cats with severe hyperthyroidism are less likely to respond to ipodate than are cats with mild or moderate disease. You’ll need to get it from a compounding pharmacist. Don’t use Propylthiouracil, the side effects are much more severe than with methimazole. Here’s a study: J Am Vet Med Assoc 1997 Jul 1;211(1):63-7 Ipodate treatment of hyperthyroidism in cats. Murray LA, Peterson ME (The "Peterson ME" is Mark Peterson of Cornell and now head of the endocrinology dept at Animal Medical Center in NYC) Thanks so much – I will post an update when I know what’s going on. Laura
Please do. Good luck. Phil. — "Cat people are different, to the extent that they generally are not conformists. How could the be, with a cat running their lives?" –Louis Camuti Feline Healthcare: http://maxshouse.com – Hide quoted text — Show quoted text – Before you buy.
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– Hide quoted text — Show quoted text – Hi, Everyone – I’m just looking for some good thoughts for Trouble. We noticed that he has been losing weight, and this past week my husband said he noticed it too. It was a gradual thing, and we both apparently initially assumed it was due to his increased activity because he plays a lot with the new kittens. However, he sometimes seems stiff in the hind region in the mornings, and his muscle mass there is clearly less – not what I’d expect if this was just an activity related weight loss. Also, he’s 9 and a half, so I called the vet and took him in this morning. Yes, the weight loss is real. (1 lb since July!!! I can’t believe I didn’t notice earlier, but his winter coat is so fluffy…) The vet thinks I’m right – drew blood and said he can palpate the thyroid and one side is noticeably larger. We find out results from the blood work tomorrow, providing everything is routine. Assuming he is Hyper-T, if he’s OK after initial treatment with tapazole, I think we’ll go for radiation if possible. Anyone with experience with this? How did your cat do? I figure Trouble has a lot of years left (I hope) so I’d like to give him the best option. Surgery seems a little risky, but I would opt for that if I can’t find a good rad place. I suspect my vet will have a lot of info for me. Thanks for listening – yes, I’m nervous on Trouble’s behalf. But at least this can be treatable. Laura
Laura, If Trouble is, in fact, hyperthyroid, monitor kidney function *very* closely while he’s on Tapazole. If there’s *any* deterioration in kidney function while he’s on antithyroid med, *do not* go ahead with any permanent thyroid treatment. Over the past few years, many small animal vets have noticed what appears to be a relatively high incidence of overt renal failure following treatment of hyperthyroidism. As the number of cats treated for hyperthyroidism increases, so has the incidence of renal failure following treatment. Hyperthyroidism or treatment of hyperthyroidism doesn’t cause renal failure, but treatment may irreversibly unmask underlying renal disease. Hyperthyroidism increases cardiac output and renal blood flow; thyrotoxicosis, therefore, could conceivably elevate glomerular filtration rate (GFR) causing renal function to appear normal and masking underlying renal disease. Following treatment of feline hyperthyroidism and return to euthyroidism, cardiac output and, hence, GFR could drop, causing clinical development of overt renal failure in cats with underlying disease. I would *thoroughly* investigate kidney function before thyroid treatment. BUN/creatinine measurements are crude and insensitive tests for renal function; ~75% of kidney function must be lost before elevations in either analyte are noticed. Despite the fact Trouble’s BUN/Creatinine may be normal, he may have underlying renal disease which may be irreversibly unmasked by I-131 Tx. Measurement of glomerular filtration rate is a much more accurate test of renal function than either serum BUN, creatinine or both – *especially* if Trouble has lean muscle loss. Because creatinine is mostly formed in muscle, a loss of muscle mass will result in elevated serum creatinine. I think you’ll find the below study of particular interest: 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 If you need any more information, please don’t hesitate to let me know. http://maxshouse.com/Endocrine_System_&_Disorders.htm#Hyperthyroidism As an aside, speak to your vet about potassium supplementation – may reduce his stiffness. Good luck. 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
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Hi, Everyone – I’m just looking for some good thoughts for Trouble. We noticed that he has been losing weight, and this past week my husband said he noticed it too. It was a gradual thing, and we both apparently initially assumed it was due to his increased activity because he plays a lot with the new kittens. However, he sometimes seems stiff in the hind region in the mornings, and his muscle mass there is clearly less – not what I’d expect if this was just an activity related weight loss. Also, he’s 9 and a half, so I called the vet and took him in this morning. Yes, the weight loss is real. (1 lb since July!!! I can’t believe I didn’t notice earlier, but his winter coat is so fluffy…) The vet thinks I’m right – drew blood and said he can palpate the thyroid and one side is noticeably larger. We find out results from the blood work tomorrow, providing everything is routine. Assuming he is Hyper-T, if he’s OK after initial treatment with tapazole, I think we’ll go for radiation if possible. Anyone with experience with this? How did your cat do? I figure Trouble has a lot of years left (I hope) so I’d like to give him the best option. Surgery seems a little risky, but I would opt for that if I can’t find a good rad place. I suspect my vet will have a lot of info for me. Thanks for listening – yes, I’m nervous on Trouble’s behalf. But at least this can be treatable. Laura Before you buy.
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