kitty update

[cellio]

I talked to the vet Monday about Erik's calcium problem (if in fact he has one). The urine analysis came back basically normal, though calcium levels were slightly elevated there too, meaning there could be a kidney problem. ("Some crystalization" is how she described it -- but not as much as she expected, she said.) The next thing to check, she says, involves another blood test, to look specifically for (consults notes) "calcium oxylate". If that comes back abnormal, then he probably has a hyper-parathyroid condition and that's treatable with drugs. If that comes back normal, then there's a possible kidney problem and a different (more expensive) test to investigate.

I asked if we could just jump to the more expensive, conclusive test and be done, but that wouldn't tell us if there's a parathyroid problem and it wouldn't be good to ignore that if he does have a problem. Oh well.

The vet is also suspicious that it might turn out that Erik just has high calcium levels and nothing's really wrong. She bases this suspicion on the fact that two years ago (first data we have) his blood-calcium level was 12.8 (something) and this time it was 13.1 -- a slight rise, but not a big one and he hasn't been sick in the meantime. (Except, I pointed out, he's been losing weight. And the cats I know who have had kidney failure have also lost significant weight. But she's not convinced that's relevant here.) Normal blood-calcium level is 8.2 to 10.8, she said.

I feel confident that the vet is doing her best to try to explain things to me, and that she's showing more concern than I'm used to from vets, but I still feel like I'm not completely getting this. I think I need to spend more time with Veterinary Partner, but I also need to ask her to write down the names of the tests she's doing and the measures she's looking for.

I have an appointment for Monday evening for her to draw more blood. (I asked if she could draw enough for both tests and set some of it aside, rather than making me come in again if we don't like the results of the first test, but she doesn't know if blood can be held that long.)

Comments

Re: A short treatise on hypercalcemia :-)

[cellio]

Wow, thank you for all the information! I really appreciate the time you've taken to do this and write it up. You've given me many ideas about what to ask my vet next time I talk to her.

1) Early renal failure.
Note: there has to be loss of >75% of kidney function before there are bloodwork changes.

She told me the 75% figure when calling with the results of the bloodwork, too. I asked how we would know if not from the bloodwork, and that's when she asked for the urine sample. But we still don't know, it seems. It sounds like the approach is "eliminate everything else first and then worry about kidneys", which is a little unsettling. I'll ask about that ERD test you mentioned. (I'll also find out what the specific gravity actually was and record it here; I didn't get that number when we talked. Actually, I'll bet I can get that from the office without specifically needing to talk with the vet.)

The reason I have a two-year-old calcium reading at all is that about two years ago I noticed that Erik was having (uncharacteristic) trouble jumping -- he couldn't jump as high and he was sometimes just plain missing his target, which never happened before that I saw. I wondered if he had injured a back leg somehow and took him to the vet. The vet found some swelling in his joints and put him on prednizone for a couple weeks, which cleared up the problem. But he also took an X-ray to rull out a hairline fracture or the like, and that X-ray happened to catch the kidneys as well, and he noticed small amounts of calcium buildup in the kidneys. (Is this the early stages of kidney stones, I wonder?) He said that wasn't necessarily worrisome but we should check his blood calcium levels, and that's when the first test was done. He also put Erik on a new diet at that time, which I gathered was low-calcium; the bag actually says "for renal failure" even though that's not what he has. (The brand is IVD, something you can only get through vets. I asked my current vet if that was appropriate food for him and she thought it was probably ok though she wouldn't have thought to prescribe it herself.)

That vet I saw two years ago is no longer available. :-(

3) Vitamin D overdose (but unless he's sneaking pills behind your back...)

She actually mentioned that the Vitamin D levels in the blood were normal, though I didn't know why that was significant at the time. (And hey, if he's sneaking pills he should share them with me; FitDay thinks I'm a little low on Vitamin D...)

Based on our conversations, I think she's focusing primarily on hyperthyroidism and hyperparathyroidism right now.

ask if they've done a check for FIP - feline infectious peritonitis

Thanks for the tip. I will ask about this, especially as there are two other cats in the house.

Neoplasia (cancer). Not likely if the Ca level has been up for 2 years already :-)

Yeah, she said much the same thing. :-)

the ever-popular "idiopathic". Means it's there, but we don't know what's causing it.

I could live with that (not that I get a vote :-) ), especially if she can suggest ways to keep it from getting out of hand and ways to monitor the kidneys before the 75% failure that causes it to show up on a blood test.

I guess I'll get my next round of data next week.