Hyperthyroid and Kidney Disease

[gardensgrow]

Nimmie and Sharon are back. I last posted April 18.

Nims new labs T-4 are 6.4 after increasing methimazole. Previous was 5.2. And then BUN was 41 on latest ... all other indicators for kidney disease are within normal ranges.

Insight is needed. What is the correlation?

Best,

Sharon and Nim

[Dr Lee]

Originally Posted by gardensgrow

Nims new labs T-4 are 6.4 after increasing methimazole. Previous was 5.2. And then BUN was 41 on latest ... all other indicators for kidney disease are within normal ranges.

The goal for T4 should be below 2. Sometimes there can be a range with the methimazole. What form are you using? liquid? tablet? topical cream? Some topical creams do have varying absorption. Could he have spit out some of the medication?

BUN is an important number but its importance is tied in with the Creatinine which is the "king" of the kidney tests. Do you know what his Creatinine is? Ideal is 1.1 and below 1.6 is acceptable (for US ranges).

[growler~GateKeeper]

The T4 number shouldn't be rising when the dose has been increased, it should be leveling or dropping, are the numbers supposed to be reversed? Are you sure he's getting the full dose & not spitting it out somewhere? Cats are notorious for sneaking off & spitting pills behind furniture

The reasons for a rise in BUN include:
- kidneys are no longer able to excrete it efficiently
- dehydration
- urethral obstruction (a blockage preventing a cat from urinating, more common in male cats)
- gastro-intestinal bleeding
- diet (it is a by-product of the breakdown of protein)
- stress

How is Nim on the way to the vet, at the vet & afterwards? Is he highly stressed?

If Nim is eating dry food only that may contribute to dehydration and/or a urethral blockage, canned or raw food will allow for extra moisture in his diet, reducing dehydration.

What are his water drinking habits? Adding extra bowls, using free flowing water fountains can sometimes help encourage water consumption.

Any changes in pee volume or frequency?

Because there are many different factors that influence BUN it alone (without changes to creatinine, phosphorus, potassium, calcium, USG numbers) can not be used as an accurate diagnosis of kidney disease, however this increase is a good reason to keep an eye out for potential future issues. A rise in BUN combined with changes in the other above mentioned numbers would point more accurately towards kidney issues.

HyperT does sometimes mask CRF if it is already present, but one doesn't cause the other. If a cat has concurrent unregulated/rising HyperT & CRF usually what happens is the CRF doesn't show on tests because with the increase in T4, the heart beating faster, the blood flows faster through the kidneys, it looks like they're cleansing more of the BUN & Cre out. When the T4 is properly regulated and the levels consistenly even for a couple of months, the CRF numbers show an increase on the blood work only because the blood flow is back to normal not because the meds caused CRF.

A cat that has both CRF & unregulated HyperT, still has damage to the kidneys even though the tests look okay. A cat with unregulated HyperT (regardless of whether they have CRF or not) is at risk for heart damage.

[gardensgrow]

Nim's methimazole (.5 ml in AM and .5 ml in PM) is liquid formulated by Pet Health Pharmacy right here in AZ. She gobbles up the methimazole in a scant teaspoon of tuna.

Her latest Creatinine = 1.9. Creatinine on 1/5/10 = 1.1, 1/27/10 = 1.3, 3/4/10 = 1.8 and then the latest on 5/19/20 = 1.9.

Her Dr. was equally puzzled by the increase in T-4 results and consulted an internal medicine colleague that was in town. He recommended a more comprehensive thyroid panel ... sorry she told what it was called and I don't remember. Nim got a new methimazole script last Thursday and the plan is to redo her labs in a month.

Extra info:

Weight 1/5/10 = 8.0 (Dr. visit found abcessed and impacted anal glands)
Started methimazole on 1/9/10
Weight 1/16/10 = 8.8 (Follow up on anal glands and update shots)
Weight 1/27/10 = 8.2 (Severe vomiting wretching began on 1/24/10)
Current Dr. emphatically diagnosed Pancreatis for vomiting and emphatically insisted she be back on thyroid meds immediately!!!
New Dr. on 2/1/10 prescribed metocopramid and now she only leaves us little grass and an occasional very small hair ball.

Ms. Nim is a rescue stray. We live in a Condo complex where everyone knows her and all have a different name for her and her forays to check on her friends will be respected by us. Thus all Ted and I want for her is the best possible life she has always lived.

Nimmie and Sharon

[growler~GateKeeper]

Why were the thyroid meds increased? Was she showing increased symptoms of HyperT or were her numbers rising from the bloodwork prior to the increase? I wonder if the dose is too high or if in combination with the metoclopramide they are reacting to each other something to have your vet look into. Are you giving both at the same time? They should ideally be given at least 2 hours apart.

The test you are refering to is probably the free T4 by equilibrium dialysis test. The T3 test should also be run, this is another hormone related to the thyroid.

To help with the excess stomach acid she apparently has raise her food & water dishes up about 2-6 inches by putting a phone book or something under them , it will help keep that which should stay in the stomach, in the stomach.

Are the neighbours feeding Nim while she is out & about? This could contribute to her vomiting especially if she has Pancreatitis as any change in food will upset the stomach & gi tract.

[gardensgrow]

Hi Growler, my name is Sharon. What is yours?

I figure it is time for you all to know more about me. Today I am 63.

My very first pet emergency was (Mom said I was 4) a clutch of baby mice. I brought them home and Mom said I couldn't keep them because they were dirty. So smart little 4 year old found a big jar added water soap and baby mice and shook them all up just like the washing machine. I have learned lots since then.

Losing a precious family member is as hard as anything I can think of. My sweet and recalcitrant Border Collie Chelsea age 13 curled up under her favorite tree after her usual 6 AM romp with horses and family and just didn't get up anymore. My friend boarding her while I traveled cried as much as I did. She is buried there.

OK back to questions from growler:

Thyroid meds increased to reduce thyroid levels.

Nim doesn't have pancreatis. Never had.

My Brother Joe died of
ALS Ameotrofic Lateral Scerlosis
He was 45.

Lou Gehrigs desease. Sorry I miss him.

Sharon