Hi Claudia, sorry about Makita's Acro/IAA test results. Good for you for getting both tests! Fiona was dx'd w/IAA in Nov 2008.
I'm not sure we can say for sure that IAA is a temporary condition. One cat, BK, resolved the IAA (without changing insulins) and was able to go OTJ. I don't know of any others. But I'm not on the board much these days so I could have missed it. If a cat is predisposed to staying diabetic, I think IAA might always be an issue. Just because BK went OTJ doesn't mean Fiona will, even though I'm as aggressive or more so with her dosing.
There is very little data out there, well none really regarding IAA in cats. But I haven't looked in over a year, so that may have changed.
Everyone I talked to vets, endo vets, researchers, authors, say change the insulin - but NO ONE I talked to has actually tried this - NO ONE. Logically it makes sense, built up antibodies to this insulin, try a different one. There is one article that says in humans changing insulin doesn't make a difference. But it's only one article. More articles say to change insulins but again, I can't find anyone who's successfully tried this. Buddy evidently changed insulins in July and is currently getting reductions. BK didn't change insulins and got good results. I tried changing Fiona to Levemir but she had a reaction to it. No one else I know has had a similar reaction, but that's why we didn't switch insulins. The "professionals" says change insulins to something closer to the cat's own insulin, like PZI. There are huge differences in opinion regarding PZI, especially regarding duration. I think Levemir is genetically closer to Lantus than PZI so is it different enough to work as a resolution for IAA? Only the shadow knows.
If you are going to change insulins, do it while still at a lesser dose rather than waiting. Less nerve racking. Knowing what I know now, I would have liked to have tried a different insulin to see if it made a difference. Even knowing BK went OTJ on the same insulin. But since Fiona does get dose reductions on Lantus, as BK did, we know the antibodies can be overwhelmed without changing the insulin. Can they be overwhelmed enough in every cat for IAA to be called a temp condition? Again, ask the shadow.
Fiona's high on Lantus was 29u BID. We're down to 17u (again) :? We can't get below 14u for some reason. I just took her back up to 17u on the 4th. Her IAA seems to wax and wane with regards to insulin resistance but I haven't found a pattern as to why. Her three IAA tests have been high 70's or low 80's, but we haven't rerun it in over a year.
The way I explain it to people is that I pretty much have to overdose Fiona on insulin to overwhelm the antibodies. Once we do that, we start lowering the dose. When this happens she's pretty much in Somogyi rebound constantly, but nothin' I can do about it. If she rebounds for too long the IAAs seem to gain ground again. (sigh)
For Fiona, I can't lower her dose more than .50u at a time. I've tried three times reducing by 1.0u but she's stalled and lost ground each time. I raise her insulin by at least one unit. Half a unit does nothing for her and I fear it gives her body time to make more antibodies. I've raised it by .50u then .50u again with no results. So I went to 1.0u as SOP. The most recent raise was 1.5u and I've done 2.0u - HOWEVER I have almost two years of data on her BG's and I work from home so I can keep an eye on her. You're not new to diabetes so I'm sure you realize every cat/human is different and what works for one might not work for another.
There's a really good explanation about IAA from a woman, Monique & Spooky, that has several antibody issues
http://felinediabetes.com/FDMB/viewtopic.php?f=9&t=4646&p=45837#p45837.
Learning how to use Humulin R saved Fiona's life (thanks to JoJo). Fiona is prone to ketones and we couldn't raise her Lantus fast enough because you never know when it's going to be too much. Plus I didn't have the data then I have now or even an IAA dx. I've also found using the Precision Xtra to test for ketones via blood instead of urine has made my life so much easier. Best strip prices on ebay.
Another note, Fiona is overweight. "Big as a house" my vet says. :roll: That certainly doesn't help and may be contributing to her inability to get below 14.0u. She's on a diet but not having much success. Even had her thyroid tested but she's not hypo. She does have a very slow metabolism. It can take her 48+ hours to rebound.
I hope this helps. I wish you and Makita all the best! You can always PM if you have questions.
