Question about Regulation and Insulin Resistance

[april_sd]

I've been having a really difficult time regulating my cat, Maddy. Currently, she is getting 3 units of Lantus BID and her numbers have remained largely unchanged. I know my vet is going to want me to take her up to 3.5 or 4 units later this week. I'm just so frustrated because her numbers remain high regardless of the amount of insulin I'm giving her.

I would really appreciated some guidance from members who have seen cases of insulin resistance.

For the past few weeks I've been trying to eliminate other possible explanations of her high numbers. Her food hasn't changed (she's eating FF classics in Turkey and Giblets and Chicken).

Insulin: I switched her to a new Lantus pen on 1/3 to make sure it wasn't just a case of the previous pen losing efficacy. Maddy has short hair and I'm able to see her skin when I give her injections, so I know I've not just been giving her fur shots.

Infection: Maddy has tested negative for UTIs on 12/15 and 1/7. Her last dental was in March 2014, and she hasn't been showing any signs of dental infection.

Acro or Cushings: I haven't had any tests to rule these out. However, she is not really showing any symptoms of either Acromelagy or Cushings. The only real symptoms she has is high BGs. Also, she recently had a CT scan of her head (Maddy has a nasal tumor that is being treated), and I assume that would show a tumor around the pituitary gland (ruling out Acro).

 

[Larry and Kitties]

I do not see much data in your spread sheet. Lantus is a depot insulin and it take 3-5 days for a dose change to reach full effectiveness. I do not see such time on 1, 1 1/2, or two units. You may have too high of a dose

 

[april_sd]

Thanks for responding, Larry.

I think you might be looking at just the data from January 1 until the present. If you open the July to December 2014 tab or the tab designed for my vet, which includes October to January, you will see that Maddy spent 11 days at 1 unit, 3 days at 1.25 units, 4 days at 1.5 units, 6 days at 1.75, and 8 days at 2 units.

 

[Larry and Kitties]

What was the CT scan for in Aug? Maddy was doing good until that time. Then there was some recovery until November. After that Maddy showed little response to the insulin.
Does your vet think there are any underlying problem causing the poor response?
You can try increasing the does and see what happens. Also, think about changing the type of insulin. I would try ProZinc or BCP PZI to instead of Levemir to get away from a depot insulin. Your vet can get a 5 ml sample of BCP PZI for free so yo can try it. It may take a month to actually get it. That is about how long it took for me last year.

 

[Wendy&Neko]

I think you are following SLGS protocol? You would only do increases of .25U (either on SLGS or TR) with the yellow nadirs. You've skipped both the 2.25U dose and the 2.75U dose so might have gone up too fast. I don't consider Maddy's dose to be that high.

Normally we don't think about testing for acromegaly or IAA until kitty is over 6U. Cushings is quite rare and is often accompanied by fragile skin (tears). Having said that, Neko didn't really have any visible signs of acromegaly, other than high dose and trying to avoid bright light. Some tumors on the pituitary can be quite small. Did you ask the person doing the CT scan if they looked at the pituitary?

 

[april_sd]

Larry, The August CT was for the same nasal tumor issue. Neither my primary vet or the specialist who is treating the nose tumor think that he glucose levels are being affected by the tumor or the treatment. Maddy doesn't appear to have an infection or other underlying condition. Our primary vet thinks her dose it just too low and the specialist recommended seeing a feline diabetes specialist about possible insulin resistance.

Wendy, I normally do increases by .25 units, but the vet totally freaked out about Maddy's numbers and wanted me to increase from 2 units to 3 right away. Going to 2.5 and then 3 was the compromise. I will talk with the specialist next week to see if there was any abnormality around her pituitary gland that showed up on the CT.