Normal glucose, elevated fructosamine: diabetes or not?

[Lisa and Angel]

Hi all,

I'm back here again with my almost 13 year old boy Oliver. I got his bloodwork results today, and while we were expecting hyperthyroidism based on symptoms, he may have diabetes instead. Weird thing is, his glucose has been normal during every test, but his fructosamine is elevated. I did a glucose check on him today as soon as I got off the phone with the vet, and that was great too (3.1 mmol/L). Has anyone seen this before? I'll post the results down below.

Symptoms: restless/hyperactive, walking around the house yowling with a toy mouse in his mouth, increased hunger and thirst but losing weight slowly, puking more, very grumpy towards the other cats and occasionally me, some bouts of diarrhea.

History: has been overweight for most of his life, been on a diet since last year and dropped (intentionally) nearly 1 kg, is almost at a healthy weight according to vet. Had a dental in february, half his remaining teeth were removed and the other half still has to go. That was planned for this month, but now we need to be sure he's healthy enough first.

Plan right now is for me to do several glucose spot checks over the next few days, and then repeat bloodwork in 2 weeks, also check blood pressure and take some x-rays to rule out pain as I notice he's sensitive around his hips. Vet also wants to watch that albumin/globulin ratio as it's borderline (I know FIP is a possibility and that terrifies me).

 

[Bron and Sheba (GA)]

@Marje and Gracie do you have any ideas about this?

 

[Marje and Gracie]

@Marje and Gracie do you have any ideas about this?

They need to look at his free T4 if concerned about hyperthyroidism.

Gracie didn’t same thing. In May, 2010, her glucose was normal when spot testing but her fructosamine was high & she occasionally had sugar in her urine. It took until July before she started showing elevated glucose on spot checks.

The fructosamine is telling you he’s exceeded normal glucose at some point. I think it’s reasonable to keep spot checking to see if you can catch him outside of normal & recheck in a few weeks. If symptoms persist, I wouldn’t let it slide.

Mornings before feeding are probably a good time to check his glucose.

 

[Lisa and Angel]

Thank you Bron and Marje for commenting!

I'll ask the vet to add free T4 to his bloodwork next time. His total T4 is normal but I swear he's behaving exactly like my other 2 hyperthyroid kitties were/are when they're hyper (prior to diagnosis and whenever they'd need a dose adjustment).

Marje, thank you for sharing about Gracie. I've spot checked a few times now on different days: once at midday (3.1), once in the evening (3.8), once in the morning prior to his breakfast (2.9) and then 30 minutes later/about 20 minutes after his carb-heavy breakfast (2.5). Am planning to check again tonight right before I go to bed, but so far it all seems perfectly normal. I think the lower glucose after breakfast means a good insulin response, is that correct?

He has lost approximately 150 grams in the last 2 weeks, though. Something is going on with him, it's also clear in his behaviour that he's just not feeling great.

Good news is, he was difficult during his first glucose check (even hissed and growled), but a few days of desensitization (and treats) have done wonders. The latest 2 checks went very smoothly. He's very big and strong but thankfully also food motivated like Angel was, which makes things easier.

We've got the follow up appointment at the vet's planned for may 18th, 2 weeks from now. Am very glad I insured this one!

 

[Lisa and Angel]

Oh wow, I'm super dumb. I thought his breakfast wet food this morning was very carb heavy, but I was wrong! I'd misremembered, or I guess just assumed it was carb heavy because it was super saucy and I though sauce=carbs. I was just checking my food spreadsheet to catch my brain up a bit and saw this one's only 7.25% carbs. Oops. I'll try again tomorrow with an actually carb heavy breakfast option.

 

[Bron and Sheba (GA)]

With those BGs under 50 you need to reduce the dose to 2.75 units at the next dose. 3 units is too much insulin.

 

[Marje and Gracie]

With those BGs under 50 you need to reduce the dose to 2.75 units at the next dose. 3 units is too much insulin.

Bron she’s discussing her cat, Oliver, not Angel.

@Lisa and Angel You don’t need to feed a carb heavy breakfast. I’d keep him LC. It looks like his pancreas is working. Glad he’s allowing g some testing. You are tracking this data, right?

 

[Bron and Sheba (GA)]

Lisa, please disregard what I said in post 6

 

[Lisa and Angel]

Thank you Bron and Marje!

Haha Bron, no worries, I know I still have Angel in my signature. I haven't made myself change it yet, it's just been too hard.

Marje, yes I am tracking the data in a notebook. If he does turn out to be diabetic I'll of course make a shiny new spreadsheet for him.

He gets a mix of food, LC and HC as well. Haven't had to worry about carbs since Angel's passing. He gets wet food for breakfast and dinner, and kibble for lunch in between. If he needs to go full LC that can be done.

I've gotten a urine sample in the meantime and done a home test with my handy urine test strips. No glucose there either. I'll bring a sample along to the vet as well for our appointment.

Right now, I can't imagine that he's actually diabetic at this point. Not enough to cause his current symptoms, at any rate. I'm reading that high or low protein can influence fructosamine levels, so maybe that's at play here. And tT4 can be falsely low due to other disease processes, so maybe he does have hyperthyroidism. And I still fear FIP, given that A/G ratio. I'm hoping our next set of blood will bring more clarity. For now, I've got these extra tests written down that I'd like to add to our next bloodwork: free T4 (maybe also TSH), HbA1c (if that's possible in my country, not sure), NT-proBNP, protein spectrum. UPC if urine sample shows protein. Anything else to add, do ya'll think?